WO2024203166A1 - Heat exchanger, and refrigeration cycle device - Google Patents

Abstract

Provided are, a heat exchanger in which a liquid refrigerant is easily distributed evenly to a plurality of first spaces, and a refrigeration cycle device including the heat exchanger. A first heat exchanger (11) is provided with a plurality of flat tubes and a first header (40). The first header includes a first member (100a), a second member (100b), and a third sub-member (130). The first member forms a plurality of first spaces (S1) into which the flat tubes are inserted. The second member forms a second space (S2) into which the refrigerant flows. The third sub-member is disposed between the first space and the second space. A flow-dividing opening (132) is formed in the third sub-member. The flow-dividing opening provides communication between the first space and the second space. The refrigerant passes through the flow-dividing opening from the second space and flows into the first space. When viewed along an insertion direction (D1) of the flat tubes with respect to the first space, the flow-dividing opening is at least partially adjacent to one end portion (144) of the second space in a width direction (D2) of the flat tubes.

Description

Heat exchanger and refrigeration cycle device

This disclosure relates to a heat exchanger and a refrigeration cycle device.

　Conventionally, as in Patent Document 1 (JP 2021-12018 A), there is known a heat exchanger that uses flat tubes as heat transfer tubes, in which the header has a number of spaces (called first spaces) into which the flat tubes are inserted, a space (called second space) into which the refrigerant introduced into the first space flows, and a first plate arranged between the first and second spaces, and in which an opening is formed in the first plate to connect the first and second spaces and distribute the refrigerant from the second space to the first space.

In Patent Document 1 (JP 2021-12018 A), when viewed along the insertion direction of the flat tube into the first space, an opening is arranged in the center of the second space in the width direction of the flat tube where the refrigerant is present, thereby diverting the refrigerant from the second space to the first space.

However, the present inventor has found that when using a heat exchanger having the structure of Patent Document 1 (JP Patent Publication No. 2021-12018), if the dryness of the refrigerant flowing into the second space increases, a difference may occur between the amount of liquid refrigerant and the amount of gaseous refrigerant flowing through each flat tube, resulting in a decrease in efficiency. From this perspective, the present inventor has found that there is room for further efficiency improvements in heat exchangers.

The heat exchanger according to the first aspect includes a plurality of flat tubes and a header. The header has a first member, a second member, and a first plate. The first member forms a plurality of first spaces into which the flat tubes are inserted. The second member forms a second space into which the refrigerant flows. The first plate is disposed between the first space and the second space. An opening is formed in the first plate. The opening connects the first space to the second space. The refrigerant flows from the second space through the opening into the first space. When viewed along the insertion direction of the flat tube into the first space, the opening is at least partially adjacent to one end of the second space in the width direction of the flat tube.

In the heat exchanger of the first aspect, the openings formed in the first plate are positioned close to the ends of the second spaces, so that the liquid refrigerant that tends to flow near the ends of the second spaces in the width direction of the flat tubes is easily distributed evenly among the multiple first spaces.

The heat exchanger according to the second aspect is the heat exchanger according to the first aspect, in which, when viewed along the insertion direction of the flat tube into the first space, the opening is at least partially adjacent to both ends of the second space in the width direction of the flat tube.

In the heat exchanger of the second aspect, the openings formed in the first plate are positioned close to both ends of the second space, so that the liquid refrigerant, which tends to flow near the ends of the second space in the width direction of the flat tube, is easily distributed evenly among the multiple first spaces.

The heat exchanger according to the third aspect is the heat exchanger according to the first or second aspect, and the width of the second space is the first width. In the width direction, the opening is at least partially provided between an end of the second space and a position 15% of the first width from the end inward of the second space.

In the heat exchanger of the third aspect, the liquid refrigerant, which tends to flow near the ends of the second spaces in the width direction of the flat tubes, tends to be distributed evenly among the multiple first spaces.

The heat exchanger according to the fourth aspect is any one of the heat exchangers according to the first aspect to the third aspect, in which, when viewed along the insertion direction of the flat tube into the first space, the opening partially overlaps one end of the second space in the width direction of the flat tube.

In the heat exchanger of the fourth aspect, the openings formed in the first plate are positioned to overlap the ends of the second spaces, so that the liquid refrigerant, which tends to flow near the ends of the second spaces in the width direction of the flat tubes, is easily distributed evenly among the multiple first spaces.

The heat exchanger according to the fifth aspect is the heat exchanger according to the fourth aspect, in which, when viewed along the insertion direction, the opening partially overlaps both ends of the second space in the width direction.

In the heat exchanger of the fifth aspect, the openings formed in the first plate are positioned so as to overlap both ends of the second space, so that the liquid refrigerant, which tends to flow near the ends of the second space in the width direction of the flat tube, is easily distributed evenly among the multiple first spaces.

The heat exchanger according to the sixth aspect is the heat exchanger according to the fifth aspect, in which the opening overlaps with the entire second space in the width direction when viewed along the insertion direction.

In the heat exchanger of the sixth aspect, the liquid refrigerant flowing through the ends of the second spaces in the width direction of the flat tubes is likely to be distributed evenly among the multiple first spaces.

The heat exchanger according to the seventh aspect is a heat exchanger according to any one of the first to sixth aspects, in which, when viewed along the insertion direction, the second member forms a main space and a sub-space. The main space has a refrigerant inlet and a refrigerant outlet. In the main space, the refrigerant moves from the refrigerant inlet to the refrigerant outlet. The sub-space guides the refrigerant that has reached the refrigerant outlet of the main space to the vicinity of the refrigerant inlet of the main space. The opening communicates with the main space as the second space.

The seventh aspect of the heat exchanger uses a loop structure having a main space and a sub-space for dividing the refrigerant, so the refrigerant is particularly likely to be distributed evenly among the multiple first spaces.

The heat exchanger according to the eighth aspect is any one of the heat exchangers according to the first aspect to the seventh aspect, in which the width of the first space is greater than the width of the second space in the width direction.

In the heat exchanger of the eighth aspect, by making the width of the first space larger than the width of the second space, it is easy to divert the liquid refrigerant flowing through the end of the second space evenly into the first space through the opening in the first plate.

The heat exchanger according to the ninth aspect is any one of the heat exchangers according to the first to eighth aspects, in which the width of the opening in the thickness direction of the flat tube is 1 mm or more.

In the heat exchanger of the ninth aspect, the width of the opening in the thickness direction of the flat tube is set to 1 mm or more, which can prevent the occurrence of problems such as liquid refrigerant having difficulty flowing through the opening.

The heat exchanger according to the tenth aspect is a heat exchanger according to any one of the first to ninth aspects, in which a single flat tube is inserted into each of the first spaces. One or more openings are provided for each of the first spaces.

In the heat exchanger of the tenth aspect, a single flat tube is inserted corresponding to each of the first spaces, and the refrigerant from the second space is guided to each of the first spaces through an opening. This makes it easier to prevent unevenness in the amount of refrigerant flowing into each flat tube, compared to a case in which multiple flat tubes are inserted into each first space and the refrigerant flowing into each first space is distributed to multiple flat tubes.

The heat exchanger according to an eleventh aspect is the heat exchanger according to any one of the first to tenth aspects, in which the plurality of flat tubes includes at least a first flat tube and a plurality of second flat tubes. In the heat exchanger, the refrigerant that flows through the first flat tube passes through a first portion of the header into which the plurality of second flat tubes are inserted, and flows into the plurality of second flat tubes. In at least the first portion of the header, when viewed along the insertion direction, an opening is at least partially adjacent to one end of the second space in the width direction.

When a refrigerant with a large amount of liquid flows through the first flat tubes and exchanges heat, the refrigerant has a high dryness when it turns around at the header and flows into the second flat tubes. In such a case, in a conventional heat exchanger, there is a possibility that a difference will occur between the amount of liquid refrigerant and gas refrigerant flowing through each of the second flat tubes, reducing the efficiency of heat exchange.

In contrast, in this heat exchanger, the liquid refrigerant is easily distributed evenly among the multiple first spaces in the first part of the header, making it easier to equalize the amounts of liquid refrigerant and gas refrigerant flowing through each of the second flat tubes.

The refrigeration cycle device according to the twelfth aspect includes a heat exchanger according to any one of the first to eleventh aspects that functions as an evaporator, a compressor that compresses a refrigerant, a radiator that cools the refrigerant discharged from the compressor, and an expansion device that expands the refrigerant that flows from the radiator to the heat exchanger.

In the refrigeration cycle device of the twelfth aspect, unevenness in the amount of refrigerant flowing into each flat tube of the heat exchanger is easily suppressed, resulting in a highly efficient refrigeration cycle device.

1 is a schematic configuration diagram of an air-conditioning apparatus according to an example of a refrigeration cycle device. FIG. 2 is a schematic perspective view of a first heat exchanger of the air conditioning apparatus of FIG. 1 according to one embodiment of the heat exchanger. FIG. 3 is a partial enlarged view of a heat exchange portion of the first heat exchanger of FIG. 2 . 4 is a schematic diagram showing a state in which fins are attached to flat tubes in the heat exchange section of the first heat exchanger of FIG. 3 . FIG. FIG. 3 is a schematic diagram of a first heat exchanger in FIG. 2 . FIG. 3 is an exploded perspective view of a first header according to an embodiment of the first heat exchanger of FIG. 2 . 13 is a cross-sectional view of the first to seventh sub-members of the first header cut along the insertion direction of the flat tube into the first header. FIG. 7 is a diagram showing a schematic diagram of a flow of refrigerant in a first portion of a first header shown in FIG. 6 when the first heat exchanger in FIG. 2 functions as an evaporator of the refrigerant. FIG. This is a diagram to explain the flow of refrigerant when the opening of the first plate is viewed along the insertion direction of the flat tube into the first space, and the opening is located in the center of the second space in the width direction of the flat tube, as in conventional heat exchangers. 7 is a schematic diagram of the inside of the first header of FIG. 6 viewed in the longitudinal direction of the first header, illustrating a first example of the arrangement of the first space, the second space, and the flow dividing openings of the first plate. 7 is a schematic diagram of the inside of the first header of FIG. 6 viewed in the longitudinal direction of the first header, illustrating a second example of the arrangement of the first space, the second space, and the flow dividing openings of the first plate. 7 is a schematic diagram of the inside of the first header of FIG. 6 viewed in the longitudinal direction of the first header, illustrating a third example of the arrangement of the first space, the second space, and the flow dividing openings of the first plate. 7 is a schematic diagram of the inside of the first header of FIG. 6 viewed in the longitudinal direction of the first header, illustrating a fourth example of the arrangement of the first space, the second space, and the flow dividing openings of the first plate. FIG. 13 is a schematic perspective view of a first heat exchanger of modification A. FIG. 15 is a diagram illustrating the flow of refrigerant when the first heat exchanger of FIG. 14 functions as an evaporator. FIG. 11 is a schematic perspective view of another example of a first heat exchanger of the modified example A. FIG. 17 is a diagram illustrating the flow of refrigerant when the first heat exchanger of FIG. 16 functions as an evaporator. FIG. 3 is an exploded perspective view of a first header according to modification D of the first heat exchanger of FIG. 2 . FIG. 20 is a cross-sectional view of the first to sixth sub-members of the first header in FIG. 18 cut along the insertion direction of the flat tube into the first header. 19 is a schematic diagram of the inside of the first header of FIG. 18 viewed in the longitudinal direction of the first header, illustrating a first example of the arrangement of the first space, the second space, and the diversion openings of the first plate. 19 is a schematic diagram of the inside of the first header of FIG. 18 viewed in the longitudinal direction of the first header, illustrating a second example of the arrangement of the first space, the second space, and the diversion openings of the first plate. 19 is a schematic diagram of the inside of the first header of FIG. 18 viewed in the longitudinal direction of the first header, illustrating a third example of the arrangement of the first space, the second space, and the diversion openings of the first plate.

Below, we will explain an embodiment of the disclosed heat exchanger and a disclosed refrigeration cycle device that uses this heat exchanger.

(1) Refrigeration Cycle Apparatus An air conditioner 1 according to an embodiment of a refrigeration cycle apparatus of the present disclosure will be described with reference to the drawings.

The air conditioning device 1 is a device capable of cooling and heating a space to be air-conditioned by performing a vapor compression refrigeration cycle. Note that the type of refrigeration cycle device disclosed herein is not limited to air conditioning devices, and may be, for example, a hot water supply device, a floor heating device, etc.

As shown in FIG. 1, the air conditioning device 1 mainly comprises a heat source unit 2, utilization units 3a and 3b, a liquid refrigerant connection pipe 4, a gas refrigerant connection pipe 5, and a control unit 50. The control unit 50 controls the operation of the components of the heat source unit 2 and utilization units 3a and 3b.

The liquid refrigerant connection pipe 4 and the gas refrigerant connection pipe 5 connect the heat source unit 2 and the utilization units 3a, 3b. In the air conditioning device 1, the heat source unit 2 and the utilization units 3a, 3b are connected via the refrigerant connection pipes 4, 5 to form a refrigerant circuit 6 (see FIG. 1). In the refrigerant circuit 6, a compressor 8, a flow direction switching mechanism 10, a first heat exchanger 11, a first expansion mechanism 12, a first shut-off valve 13, a second shut-off valve 14, a second expansion mechanism 31a, 31b, and a second heat exchanger 32a, 32a, which will be described later, are connected by refrigerant piping as shown in FIG. 1. The first heat exchanger 11 is an example of a heat exchanger of the present disclosure.

In FIG. 1, the air conditioning device 1 has one heat source unit 2 and two utilization units 3a, 3b, but this number is merely an example. The air conditioning device 1 may have multiple heat source units, and one utilization unit or three or more utilization units. The air conditioning device 1 may also be an integrated air conditioning device in which the heat source unit and utilization units are integrally formed.

A refrigerant with a small global warming potential, such as R290 or _CO2 , is filled in the refrigerant circuit 6. However, the type of refrigerant is not limited to R290 or _CO2 , and may be R32, R410A, R1234yf, R1234ze(E), or the like.

(2) Detailed Configuration of the Air Conditioner Below, the heat source unit 2, utilization units 3a, 3b, liquid refrigerant connection pipe 4, gas refrigerant connection pipe 5, and control unit 50 of the air conditioner 1 will be described.

(2-1) Heat Source Unit The heat source unit 2 is installed outdoors, for example, on the roof of the building in which the air conditioning device 1 is installed, or around the exterior wall of the building, although this is not limited thereto.

The heat source unit 2 of this embodiment is an upward-blowing type unit that takes in air from the side of a housing (not shown) that houses various devices of the heat source unit 2, and blows out the air that has exchanged heat with the refrigerant from above the housing. However, the type of heat source unit 2 is not limited to the upward-blowing type, and it may be a side-blowing type that blows out the air that has exchanged heat with the refrigerant from the side of the housing.

The heat source unit 2 mainly includes an accumulator 7, a compressor 8, a flow direction switching mechanism 10, a first heat exchanger 11, a first expansion mechanism 12, a first shut-off valve 13, a second shut-off valve 14, and a first fan 15 (see Figure 1).

The heat source unit 2 also has a suction pipe 17, a discharge pipe 18, a first gas refrigerant pipe 19, a liquid refrigerant pipe 20, and a second gas refrigerant pipe 21 (see FIG. 1). The suction pipe 17 connects the flow direction switching mechanism 10 and the suction side of the compressor 8. The accumulator 7 is provided in the suction pipe 17. The discharge pipe 18 connects the discharge side of the compressor 8 and the flow direction switching mechanism 10. The first gas refrigerant pipe 19 connects the flow direction switching mechanism 10 and the gas end of the first heat exchanger 11. The liquid refrigerant pipe 20 connects the liquid end of the first heat exchanger 11 and the first shutoff valve 13. The first expansion mechanism 12 is provided in the liquid refrigerant pipe 20. The second gas refrigerant pipe 21 connects the flow direction switching mechanism 10 and the second shutoff valve 14.

(2-1-1) Compressor The compressor 8 is a device that draws in low-pressure refrigerant in the refrigeration cycle flowing in from a suction pipe 17, compresses the refrigerant to increase its pressure to the high pressure in the refrigeration cycle, and discharges it to a discharge pipe 18. The compressor 8 is, for example, a positive displacement compressor, but may be another type (a centrifugal compressor).

(2-1-2) Flow Direction Switching Mechanism The flow direction switching mechanism 10 is a mechanism that switches the flow direction of the refrigerant in the refrigerant circuit 6. In this embodiment, the flow direction switching mechanism 10 is a four-way switching valve.

During cooling and defrosting operations, the flow direction switching mechanism 10 connects the suction pipe 17 to the second gas refrigerant pipe 21 and the discharge pipe 18 to the first gas refrigerant pipe 19 (this piping connection state by the flow direction switching mechanism 10 is called the first state), thereby switching the flow direction of the refrigerant in the refrigerant circuit 6 so that the refrigerant discharged by the compressor 8 is sent to the first heat exchanger 11 (see solid lines in Figure 1).

During heating operation, the flow direction switching mechanism 10 connects the suction pipe 17 to the first gas refrigerant pipe 19 and the discharge pipe 18 to the second gas refrigerant pipe 21 (this piping connection state by the flow direction switching mechanism 10 is called the second state), switching the flow direction of the refrigerant in the refrigerant circuit 6 so that the refrigerant discharged from the compressor 8 is sent to the second heat exchangers 32a and 32b (see dashed lines in Figure 1).

The flow direction switching mechanism 10 is not limited to a four-way switching valve, but may be configured to combine multiple solenoid valves and refrigerant pipes to achieve the above-mentioned switching of the refrigerant flow direction.

(2-1-3) First Heat Exchanger The first heat exchanger 11 functions as a radiator (condenser) during cooling operation/defrost operation, and functions as an evaporator (heat absorber) during heating operation. The first heat exchanger 11 is an example of a heat exchanger in the claims.

The structure of the first heat exchanger 11 and the flow of the refrigerant in the first heat exchanger 11 will be explained later.

(2-1-4) First Expansion Mechanism The first expansion mechanism 12 is a mechanism for expanding the refrigerant flowing between the second heat exchangers 32a, 32b of the utilization units 3a, 3b and the first heat exchanger 11 in the refrigerant circuit 6. The first expansion mechanism 12 is, for example, an electronic expansion valve whose opening degree is adjustable. The opening degree of the first expansion mechanism 12 is adjusted by the control unit 50 according to the operating conditions.

(2-1-5) First Fan The first fan 15 generates an airflow and supplies air to the first heat exchanger 11. The first fan 15 generates a flow of air that flows from outside the housing into the heat source unit 2, passes through the first heat exchanger 11, and flows out of the housing. The first fan 15 is, for example, a propeller fan. However, the type of the first fan 15 is not limited to a propeller fan, and may be another type of fan.

(2-2) Utilization Unit The utilization units 3a, 3b are installed in the space to be air conditioned or in the vicinity of the space to be air conditioned (for example, in the attic space of the space to be air conditioned).

The utilization unit 3a mainly includes a second expansion mechanism 31a, a second heat exchanger 32a, and a second fan 33a (see FIG. 1). The utilization unit 3b mainly includes a second expansion mechanism 31b, a second heat exchanger 32b, and a second fan 33b (see FIG. 1).

(2-2-1) Second Expansion Mechanism The second expansion mechanisms 31a, 31b are mechanisms for expanding the refrigerant flowing between the second heat exchangers 32a, 32b of the utilization units 3a, 3b and the first heat exchanger 11 in the refrigerant circuit 6. The second expansion mechanisms 31a, 31b are, for example, electronic expansion valves with adjustable opening. The opening of the second expansion mechanisms 31a, 31b is adjusted by the control unit 50 according to the operating conditions.

(2-2-2) Second Heat Exchanger The second heat exchangers 32a, 32b function as heat absorbers (evaporators) during cooling operation to cool the indoor air, and function as refrigerant radiators (condensers) during heating operation to heat the indoor air.

The liquid side of the second heat exchangers 32a, 32b is connected to the liquid refrigerant connection pipe 4 via a refrigerant pipe, and the gas side of the second heat exchangers 32a, 32b is connected to the gas refrigerant connection pipe 5 via a refrigerant pipe. The second heat exchangers 32a, 32b are, for example, cross-fin type fin-and-tube heat exchangers having multiple heat transfer tubes (not shown) and multiple fins (not shown).

Here, the second heat exchangers 32a and 32b exchange heat between the refrigerant and air, but the second heat exchanger of the utilization unit may be a heat exchanger that exchanges heat between the refrigerant and water.

(2-2-3) Second Fan The second fans 33a, 33b generate a flow of air that flows from the outside (air-conditioned space) of a housing (not shown) that houses various devices of the utilization units 3a, 3b inside, into the utilization units 3a, 3b, passes through the second heat exchangers 32a, 32b, and flows out of the housing (air-conditioned space). The second fans 33a, 33b are, for example, centrifugal fans.

(2-3) Refrigerant connection pipe The refrigerant connection pipes 4, 5 are refrigerant piping that is installed on-site when the air-conditioning apparatus 1 is installed. One end of the liquid refrigerant connection pipe 4 is connected to the first shutoff valve 13 of the heat source unit 2, and the other end of the liquid refrigerant connection pipe 4 is connected to refrigerant piping that is connected to the liquid sides of the second heat exchangers 32a, 32b of the utilization units 3a, 3b (see FIG. 1). One end of the gas refrigerant connection pipe 5 is connected to the second shutoff valve 14 of the heat source unit 2, and the other end of the gas refrigerant connection pipe 5 is connected to refrigerant piping that is connected to the gas sides of the second heat exchangers 32a, 32b of the utilization units 3a, 3b (see FIG. 1).

(2-4) Control Unit The control unit 50 is configured by communicatively connecting a control board (not shown) having a CPU, ROM, RAM, etc., provided in the heat source unit 2 and the utilization units 3a and 3b. For convenience, the control unit 50 is illustrated in FIG. 1 as being located away from the heat source unit 2 and the utilization units 3a and 3b.

The control unit 50 is electrically connected to the components of the air conditioning device 1, as shown by the dashed lines in FIG. 1. Specifically, the control unit 50 is electrically connected to, for example, the compressor 8, the flow direction switching mechanism 10, the first expansion mechanism 12, the first fan 15, the second expansion mechanisms 31a and 31b, and the second fans 33a and 33b. The control unit 50 is also electrically connected to various sensors (not shown) provided in the heat source unit 2 and the utilization units 3a and 3b.

The control unit 50 executes a program for controlling the air conditioning device 1 (the CPU executes a program stored in the ROM), and controls the components of the air conditioning device 1 based on operations from a remote control (not shown) and measurement values of various sensors (not shown).

The control unit 50 controls the components of the air conditioning unit 1 to cause the air conditioning unit 1 to perform cooling operation or heating operation. In addition, when a specific condition is met during the heating operation of the air conditioning unit 1, the control unit 50 switches the operation of the air conditioning unit 1 to defrost operation. The operation of the air conditioning unit 1 during each operation is shown below.

(3) Operation of the Air Conditioning Apparatus We will now explain the cooling operation, heating operation, and defrost operation of the air conditioning apparatus 1. The defrost operation is an operation that is performed by temporarily interrupting the heating operation during the heating operation, in order to melt frost and ice that has adhered to the first heat exchanger 11.

During cooling and defrosting operations, the refrigerant circulates through the refrigerant circuit 6 in the following order: compressor 8, first heat exchanger 11, first expansion mechanism 12, second expansion mechanisms 31a and 31b, second heat exchangers 32a and 32b, and accumulator 7.

During heating operation, the refrigerant circulates through the refrigerant circuit 6 in the following order: compressor 8, second heat exchangers 32a and 32b, second expansion mechanisms 31a and 31b, first expansion mechanism 12, first heat exchanger 11, and accumulator 7.

The operation of the air conditioner 1 during cooling operation will be explained.

During cooling operation, the connection state of the piping by the flow direction switching mechanism 10 is switched to the first state described above. Then, the low-pressure gas refrigerant in the refrigeration cycle (hereinafter simply referred to as low pressure) sucked into the compressor 8 from the suction pipe 17 is compressed in the compressor 8 until it becomes the high-pressure gas refrigerant in the refrigeration cycle (hereinafter simply referred to as high pressure), and then discharged to the discharge pipe 18. The high-pressure gas refrigerant discharged to the discharge pipe 18 is sent to the first heat exchanger 11 through the flow direction switching mechanism 10. The high-pressure gas refrigerant sent to the first heat exchanger 11 exchanges heat with the air supplied by the first fan 15 in the first heat exchanger 11, which functions as a refrigerant radiator, to release heat, and becomes a high-pressure liquid refrigerant. The high-pressure liquid refrigerant that has released heat in the first heat exchanger 11 is sent to the second expansion mechanisms 31a and 31b through the first expansion mechanism 12, the first shutoff valve 13, and the liquid refrigerant connection pipe 4. The refrigerant sent to the second expansion mechanisms 31a and 31b is decompressed to a low pressure by the second expansion mechanisms 31a and 31b, becoming a low-pressure gas-liquid two-phase refrigerant. The low-pressure gas-liquid two-phase refrigerant decompressed by the second expansion mechanisms 31a and 31b is sent to the second heat exchangers 32a and 32b. The low-pressure gas-liquid two-phase refrigerant sent to the second heat exchangers 32a and 32b exchanges heat with the air supplied by the second fans 33a and 33b in the second heat exchangers 32a and 32b and evaporates. The air cooled in the second heat exchangers 32a and 32b is blown out into the space to be air-conditioned. The low-pressure gas refrigerant evaporated in the second heat exchangers 32a and 32b passes through the gas refrigerant communication pipe 5, the second shutoff valve 14, the flow direction switching mechanism 10, and the accumulator 7, and is sucked back into the compressor 8.

During cooling operation, the control unit 50 performs control such as the following. Note that the control mode by the control unit 50 described here is an example and is not limited to this.

The control unit 50 controls the opening degree of an electronic expansion valve (an example of an electronic expansion valve) of each of the second expansion mechanisms 31a, 31b so that the degree of superheat of the refrigerant at the outlet of each of the second heat exchangers 32a, 32b becomes the target degree of superheat based on the measurement value of a sensor (not shown). The control unit 50 also controls the operating capacity of the compressor 8 so that the evaporation temperature approaches the target evaporation temperature.

The operation of the air conditioner 1 during heating operation will be explained.

During heating operation, the connection state of the piping is switched to the second state by the flow direction switching mechanism 10. The low-pressure gas refrigerant sucked into the compressor 8 from the suction pipe 17 is compressed to high pressure by the compressor 8 and then discharged to the discharge pipe 18. The high-pressure gas refrigerant discharged to the discharge pipe 18 is sent to the second heat exchangers 32a, 32b through the flow direction switching mechanism 10, the second shutoff valve 14, and the gas refrigerant communication pipe 5. The high-pressure gas refrigerant sent to the second heat exchangers 32a, 32b exchanges heat with the air supplied by the second fans 33a, 33b in the second heat exchangers 32a, 32b, dissipating heat and becoming a high-pressure liquid refrigerant or a two-phase gas-liquid refrigerant. The air heated by heat exchange with the refrigerant in the second heat exchangers 32a, 32b is blown out into the space to be air-conditioned. The high-pressure refrigerant that has released heat in the second heat exchangers 32a and 32b is sent to the first expansion mechanism 12 through the second expansion mechanisms 31a and 31b, the liquid refrigerant communication pipe 4, and the first closing valve 13. The refrigerant sent to the first expansion mechanism 12 is decompressed by the first expansion mechanism 12 to become a low-pressure gas-liquid two-phase refrigerant. The low-pressure gas-liquid two-phase refrigerant decompressed by the first expansion mechanism 12 is sent to the first heat exchanger 11. The low-pressure gas-liquid two-phase refrigerant sent to the first heat exchanger 11 evaporates by heat exchange with the air supplied by the first fan 15 in the first heat exchanger 11, which functions as a refrigerant evaporator, to become a low-pressure gas refrigerant. The low-pressure refrigerant evaporated in the first heat exchanger 11 passes through the flow direction switching mechanism 10 and the accumulator 7 and is sucked back into the compressor 8.

During heating operation, the control unit 50 performs control such as the following. Note that the control mode by the control unit 50 described here is an example and is not limited to this.

The control unit 50 controls the opening degree of an electronic expansion valve, which is an example of a first expansion mechanism 12, so that the degree of superheat of the refrigerant at the outlet of the first heat exchanger 11 becomes the target degree of superheat based on the measurement value of a sensor (not shown). The control unit 50 also controls the operating capacity of the compressor 8 so that the evaporation temperature approaches the target evaporation temperature. The control unit 50 also controls the opening degree of an electronic expansion valve, which is an example of the first expansion mechanism 12, so that the dryness of the refrigerant at the inlet of the first heat exchanger 11 becomes a predetermined value.

When the conditions for starting the defrost operation are met during heating operation, the control unit 50 temporarily switches the operation of the air conditioner 1 from heating operation to defrost operation in order to defrost the first heat exchanger 11, causing the first heat exchanger 11 to function as a radiator. When the conditions for ending the defrost operation are met, the control unit 50 ends the defrost operation and returns the operation of the air conditioner 1 to heating operation. A description of the control contents of the control unit 50 during defrost operation will be omitted.

(4) First Heat Exchanger With reference to the drawings, a configuration of the first heat exchanger 11 according to one embodiment of the heat exchanger of the present disclosure will be described.

FIG. 2 is a schematic perspective view of the first heat exchanger 11. FIG. 3 is a partially enlarged view of the heat exchange section 27 of the first heat exchanger 11, which will be described later. FIG. 4 is a schematic view showing the attachment state of the fins 29, which will be described later, to the flat tubes 28 in the heat exchange section 27. FIG. 5 is a schematic configuration diagram of the first heat exchanger 11. FIG. 5 also illustrates the flow of the refrigerant when the first heat exchanger 11 functions as an evaporator of the refrigerant. Note that in the first heat exchanger 11 of this embodiment, the flat tubes 28 are bent at two points to form an approximately U-shape as shown in FIG. 2, but in FIG. 5, the flat tubes 28 are illustrated as straight lines.

In the following description, expressions such as "upper," "lower," "left," "right," "front," and "rear" may be used to describe directions and positions. Unless otherwise specified, these expressions follow the directions of the arrows drawn in Figure 2. Note that these expressions indicating directions and positions are used for the convenience of explanation, and unless otherwise specified, do not specify the direction or position of the first heat exchanger 11 as a whole or each component of the first heat exchanger 11 to the direction or position of the expressions described.

In the first heat exchanger 11, heat exchange takes place between the refrigerant flowing inside and the air supplied by the first fan 15.

As shown in Figures 4 and 5, the first heat exchanger 11 mainly includes a flow divider 22, a plurality of flat tubes 28, fins 29 attached to the flat tubes 28, a first header 40 (one example of a header in the claims), and a second header 70. In this embodiment, the flow divider 22, flat tubes 28, fins 29, first header 40, and second header 70 of the first heat exchanger 11 are all made of aluminum or an aluminum alloy.

The flat tubes 28 and the fins 29 attached to the flat tubes 28 form a heat exchange section 27 (see Figs. 2 and 3). The first heat exchanger 11 has one row of heat exchange sections 27. However, the first heat exchanger 11 may have multiple rows of heat exchange sections 27 (flat tubes 28) arranged in the air flow direction. In the first heat exchanger 11, air flows through the ventilation passage formed by the flat tubes 28 and the fins 29 of the heat exchange section 27, and heat is exchanged between the refrigerant flowing through the flat tubes 28 and the air flowing through the ventilation passage. The heat exchange section 27 is, for example, divided into a first heat exchange section 27a, a second heat exchange section 27b, a third heat exchange section 27c, a fourth heat exchange section 27d, and a fifth heat exchange section 27e arranged in the vertical direction, although this is not limited thereto (see Fig. 2).

(4-1) Flow Divider The flow divider 22 is a mechanism for dividing the refrigerant. The flow divider 22 is also a mechanism for joining the refrigerant. The liquid refrigerant pipe 20 is connected to the flow divider 22. The flow divider 22 has a plurality of branch pipes 22a to 22e, and divides the refrigerant that flows into the flow divider 22 from the liquid refrigerant pipe 20 into the plurality of branch pipes 22a to 22e, and guides it to a plurality of spaces formed in the first header 40. The flow divider 22 also joins the refrigerant that flows in from the first header 40 via the branch pipes 22a to 22e, and guides it to the liquid refrigerant pipe 20.

The connection between the flow divider 22 and the first header 40 will be specifically described. The first header 40 is connected to connection pipes 49a-49e that communicate with the internal space 23 of the first header 40. As shown in FIG. 5, each of the connection pipes 49a-49e is connected to a plurality of sub-spaces 23a-23e (described below) that correspond to each of the heat exchange sections 27a-27e. Also, each of the connection pipes 49a-49e is connected to a branch pipe 22a-22e. As a result, the internal space 23 (sub-spaces 23a-23e) of the first header 40 and the liquid refrigerant pipe 20 are connected via the branch pipes 22a-22e and the connection pipes 49a-49e.

(4-2) Flat Tube The first heat exchanger 11 has a plurality of flat tubes 28. The flat tubes 28 are flat heat transfer tubes with a thin thickness. As shown in FIG. 3, each flat tube 28 has flat surfaces 28a that serve as heat transfer surfaces at both ends in the thickness direction (in the vertical direction in the installed state of the air conditioning device 1 of the present disclosure). In the flat tube 28, a plurality of refrigerant passages 28b through which the refrigerant flows are formed along the extension direction of the flat tube 28, as shown in FIG. 3. The flat tube 28 is, for example, a flat multi-hole tube in which a large number of refrigerant passages 28b with small passage areas through which the refrigerant flows are formed. In this embodiment, the plurality of refrigerant passages 28b of each flat tube 28 are arranged side by side in the air flow direction.

In the first heat exchanger 11, as shown in FIG. 5, flat tubes 28 extending horizontally between the first header 40 side and the second header 70 side are arranged in multiple rows in the vertical direction with a predetermined interval between them. Hereinafter, the direction in which the multiple flat tubes 28 are arranged may be referred to as the row direction. Although the shape is not limited, in this embodiment, the flat tubes 28 extending between the first header 40 side and the second header 70 side are bent at two places, and the heat exchange section 27 formed by the flat tubes 28 is formed into an approximately U-shape in a plan view (see FIG. 2). However, the flat tubes 28 may be bent at one place or at three or more places, or may not have any bent portions.

(4-3) Fins The multiple fins 29 are members for increasing the heat transfer area of the first heat exchanger 11. Each fin 29 is a plate-shaped member extending in the row direction (the up-down direction in this embodiment).

Each fin 29 has a plurality of notches 29a extending along the insertion direction of the flat tubes 28 as shown in FIG. 4 so that a plurality of flat tubes 28 can be inserted. The notches 29a extend in the direction in which the fins 29 extend and in a direction perpendicular to the thickness direction of the fins 29. When the first heat exchanger 11 is installed in the heat source unit 2, the notches 29a formed in each fin 29 extend horizontally. The shape of the notches 29a in the fins 29 approximately matches the outer shape of the cross section of the flat tubes 28. The notches 29a are formed in the fins 29 at intervals corresponding to the arrangement intervals of the flat tubes 28. In the first heat exchanger 11, the multiple fins 29 are arranged side by side along the extension direction of the flat tubes 28. By inserting flat tubes 28 into each of the multiple notches 29a of the multiple fins 29, the space between adjacent flat tubes 28 is divided into multiple ventilation passages through which air flows.

Each fin 29 has a communication section 29b that communicates in the vertical direction on the upstream or downstream side of the air flow direction relative to the flat tube 28. In this embodiment, the communication section 29b of the fin 29 is located on the upwind side of the flat tube 28.

(4-4) First Header and Second Header The first header 40 and the second header 70 are hollow members having an internal space. The first header 40 and the second header 70 have the functions of distributing the refrigerant flowing in from outside the first heat exchanger 11 to the connected flat tubes 28, and merging the refrigerant flowing in from the connected flat tubes 28 and allowing it to flow out to the outside of the first heat exchanger 11.

In this embodiment, the first heat exchanger 11 is disposed within a casing (not shown) of the heat source unit 2 so that the longitudinal direction of the first header 40 and the second header 70 roughly coincides with the vertical direction.

(4-4-1) Second Header The second header 70 is a hollow member, and has an internal space 25 as shown in FIG.

A connecting pipe 19a is attached to the second header 70. The connecting pipe 19a is a pipe to which the first gas refrigerant pipe 19 is connected. In addition, one end of a plurality of flat tubes 28 is connected to the second header 70. The internal space 25 of the second header 70 communicates with the first gas refrigerant pipe 19 connected to the connecting pipe 19a via the connecting pipe 19a. In addition, the internal space 25 of the second header 70 communicates with the refrigerant passage 28b of the connected flat tube 28.

When the first heat exchanger 11 functions as a radiator (during cooling or defrosting operation), the second header 70 distributes the refrigerant that flows through the first gas refrigerant pipe 19 and into the internal space 25 via the connecting pipe 19a to the flat tubes 28 connected to the second header 70. When the first heat exchanger 11 functions as an evaporator (during heating operation), the second header 70 has the function of merging the refrigerant that flows into the internal space 25 from the flat tubes 28 connected to the second header 70 and directing it to the connecting pipe 19a.

(4-4-2) First Header The first header 40 is a hollow member, and has an internal space 23 as shown in FIG.

The internal space 23 of the first header 40 is divided into a number of subspaces 23a to 23e (see FIG. 5). Each of the subspaces 23a to 23e corresponds to a heat exchange section 27a to 27e. How the internal space 23 is divided can be changed as appropriate depending on how the refrigerant flows in the first heat exchanger 11, etc.

The subspaces 23a, 23b, 23c, 23d, and 23e are arranged vertically in this order from above. The subspaces 23a to 23e are not connected to one another in the internal space 23 of the first header 40. In the following, the portions of the first header 40 in which the subspaces 23a, 23b, 23c, 23d, and 23e are formed are referred to as the first portion 42a, the second portion 42b, the third portion 42c, the fourth portion 42d, and the fifth portion 42e, respectively (see FIG. 5).

Each of the subspaces 23a to 23e is connected to one of the connecting pipes 49a to 49e attached to the portions 42a to 42e. As described above, one of the branch pipes 22a to 22e of the flow divider 22 is connected to each of the connecting pipes 49a to 49e. In addition, one end of one or more flat tubes 28 is connected to each of the subspaces 23a to 23e of the first header 40. Each of the subspaces 23a to 23e of the first header 40 is connected to the liquid refrigerant pipe 20 via the connecting pipes 49a to 49e and the branch pipes 22a to 22e connected to the connecting pipes 49a to 49e. In addition, each of the subspaces 23a to 23e of the first header 40 is connected to the refrigerant passage 28b of the flat tube 28 to which it is connected.

When the first heat exchanger 11 functions as a radiator, the refrigerant that reaches each of the sub-spaces 23a to 23e through the flat tubes 28 flows through the connecting tubes 49a to 49e and the diverter 22 connected to each of the sub-spaces 23a to 23e to the liquid refrigerant tube 20. Also, when the first heat exchanger 11 functions as an evaporator, the refrigerant that flows into each of the sub-spaces 23a to 23e through the liquid refrigerant tube 20, the diverter 22, and the connecting tubes 49a to 49e is further diverted in each of the sub-spaces 23a to 23e and is guided to each of the flat tubes 28.

The structure of the first header 40 will be described in detail later.

(4-5) Refrigerant flow in the first heat exchanger When the first heat exchanger 11 functions as a refrigerant evaporator, the gas-liquid two-phase refrigerant that flows from the liquid refrigerant tube 20 into the diverter 22 flows into each of the subspaces 23a to 23e of the first header 40 through the diverter tubes 22a to 22e and the connecting tubes 49a to 49e connected thereto. The refrigerant that flows into each of the subspaces 23a to 23e flows through each of the flat tubes 28 connected to the subspaces 23a to 23e. The refrigerant that flows through each of the flat tubes 28 exchanges heat with the air and evaporates, becoming a gas-phase refrigerant that flows into the internal space 25 of the second header 70. The refrigerant that flows into the internal space 25 of the second header 70 and merges flows into the first gas refrigerant tube 19 through the connecting tube 19a.

When the first heat exchanger 11 functions as a refrigerant radiator, the refrigerant flows in the opposite direction to when the first heat exchanger 11 functions as a refrigerant evaporator. Specifically, the gas phase refrigerant discharged from the compressor 8 and flowing through the first gas refrigerant tube 19 flows into the internal space 25 of the second header 70 via the connecting tube 19a. The refrigerant that flows into the internal space 25 of the second header 70 is divided and flows into each flat tube 28. The refrigerant that flows into each flat tube 28 dissipates heat as it passes through each flat tube 28 and flows into the subspaces 23a to 23e of the first header 40. The refrigerant that flows into the subspaces 23a to 23e flows through the connecting tubes 49a to 49e and the dividing tubes 22a to 22e, respectively, merges at the dividing device 22, and flows out into the liquid refrigerant tube 20.

(4-6) Details of the First Header The structure of the first header 40 will be described in detail with reference to FIGS.

FIG. 6 is a schematic exploded perspective view of the first header 40. Note that FIG. 6 depicts only a portion of the first header 40 (the portion forming the first portion 42a of the first header 40 and the upper portion of the second portion 42b of the first header 40). The dashed double-dashed arrows in FIG. 6 indicate the refrigerant flow when the first heat exchanger 11 functions as an evaporator of the refrigerant (when the air conditioning device 1 is in heating operation).

Figure 7 shows a cross-sectional view of each of the first sub-members 110 to seventh sub-members 170 of the first header 40 (described below) cut at a predetermined position along the first direction D1 (the insertion direction of the flat tubes 28 into the first header 40).

The first header 40 has a first sub-member 110 to a seventh sub-member 170. The first sub-member 110, the second sub-member 120, the third sub-member 130, the fourth sub-member 140, the fifth sub-member 150, the sixth sub-member 160, and the seventh sub-member 170 are stacked in this order along the first direction D1 of the flat tubes 28 relative to the first header 40. Note that, as shown by the arrows in FIG. 6, in the direction in which the sub-members 110 to 170 are arranged, the side on which the first sub-member 110 is arranged (the side on which the flat tubes 28 are inserted) is referred to as the rear, and the side on which the seventh sub-member 170 is arranged (the side on which the connecting pipes 49a to 49e are inserted) is referred to as the front.

The first header 40 is formed by brazing the first sub-member 110 to the seventh sub-member 170 together, and an internal space 23 (sub-spaces 23a to 23e) is formed inside. The first header 40, which is formed by stacking the first sub-member 110 to the seventh sub-member 170, is configured so that its external shape in a plan view is approximately rectangular.

The plate thickness of the first sub-member 110, the third sub-member 130, the fourth sub-member 140, the fifth sub-member 150, the sixth sub-member 160, and the seventh sub-member 170 is about several mm (e.g., 3 mm or less).

The first sub-member 110 and the second sub-member 120 constitute the first member 100a in the claims. The third sub-member 130, the fourth sub-member 140, and the fifth sub-member 150 constitute the second member 100b in the claims. The third sub-member 130 is an example of the first material in the claims. Note that here, the third sub-member 130 constitutes part of the second member 100b and functions as the first material, but this form is merely one example. The first material may be formed as a separate member from the second member 100b.

(4-6-1) First Sub-member The first sub-member 110 is a member in which a flat tube connection opening 112a into which the flat tube 28 is inserted is formed, as shown in Fig. 6. In Fig. 7, a cross-sectional view of the first sub-member 110 cut along the first direction D1 at a position in the stage direction where the flat tube connection opening 112a is formed is drawn. The first sub-member 110 is also a member that constitutes the outer periphery of the first header 40 together with the seventh sub-member 170. It is preferable that the first sub-member 110 has a clad layer having a brazing material formed on its surface.

As shown in Figures 6 and 7, the first sub-member 110 has a flat tube connecting plate 112, a pair of outer wall portions 114, and a pair of claw portions 116. Although the manufacturing method is not limited, the first sub-member 110 of this embodiment is formed by bending a single sheet metal obtained by rolling. When manufactured in this manner, the sheet thickness of each portion of the first sub-member 110 is uniform.

The flat tube connection plate 112 is a flat plate-shaped portion extending in the vertical direction. As shown in FIG. 6, the flat tube connection plate 112 has a plurality of flat tube connection openings 112a arranged in a line in the vertical direction. Each flat tube connection opening 112a penetrates the flat tube connection plate 112 in the thickness direction (first direction D1) of the flat tube connection plate 112. The flat tube 28 is joined by brazing in a state where one end of the flat tube 28 is inserted into the flat tube connection opening 112a so that it passes completely through. In the brazed joint state, the entire inner surface of the flat tube connection opening 112a and the entire outer surface of the flat tube 28 are in contact with each other.

As shown in FIG. 7, each of the pair of outer wall portions 114 is a flat plate-shaped portion that extends forward from the left and right ends of the flat tube connection plate 112 (from both ends in the second direction D2 perpendicular to the first direction D1).

As shown in FIG. 7, each of the pair of claws 116 extends from the front end of each outer wall portion 114 in a direction approaching each other. When the second sub-member 120 to the seventh sub-member 170 are arranged inside the first sub-member 110 in a plan view, the pair of claws 116 are bent so as to approach each other and be pressed against the front surface of the seventh sub-member 170. As a result, the first sub-member 110 to the seventh sub-member 170 are temporarily fixed. In this state, brazing is performed in a furnace or the like, and the first sub-member 110 to the seventh sub-member 170 are fixed to each other by brazing.

6, the second sub-member 120 has a plate-shaped base portion 122 and a plurality of protrusions 124 protruding from the base portion 122 toward the flat tube connecting plate 112. The second sub-member 120 may have a clad layer having a brazing material formed on its surface.

The base portion 122 is a flat member that extends parallel to the flat tube connecting plate 112 and has a plate thickness direction that is the same as the extension direction of the flat tubes 28. The left-right width of the base portion 122 is the same as the left-right width of the inner surface of the flat tube connecting plate 112. The base portion 122 has a plurality of protrusions 124 arranged vertically. In addition, a communication hole 122a is formed between adjacent protrusions 124 of the base portion 122. The base portion 122 has a plurality of communication holes 122a arranged vertically. Each communication hole 122a corresponds one-to-one with one flat tube 28, and is shaped to roughly overlap the end of the flat tube 28 when viewed from the rear.

In FIG. 7, a cross-sectional view of the second sub-member 120 is drawn taken along the first direction D1 at the position where the communication hole 122a is formed in the step direction.

The multiple protrusions 124 are formed so as to extend horizontally from between adjacent communication holes 122a of the base portion 122 toward the rear until they hit the front surface of the flat tube connection plate 112. As a result, a first space S1 is formed that is surrounded by the front surface of the flat tube connection plate 112 of the first sub-member 110, the outer wall portion 114 of the first sub-member 110, the vertically adjacent protrusions 124 of the second sub-member 120, and the portion of the rear surface of the base portion 122 of the second sub-member 120 other than the communication holes 122a. Since the base portion 122 is provided with multiple protrusions 124 and multiple communication holes 122a along the vertical direction, the first space S1 is formed so as to be lined up in multiple positions in the longitudinal direction of the first header 40. Each of the multiple first spaces S1 is a space independent of the other first spaces S1. A single corresponding flat tube 28 is inserted into each first space S1, and the end of the flat tube 28 is positioned therein. The first sub-member 110 and the second sub-member 120 that form the first space S1 constitute the first member 100a.

(4-6-3) Third Sub-member The third sub-member 130 is an example of the first plate in the claims.

The third sub-member 130 is laminated so that its rear surface contacts the front surface of the base portion 122 of the second sub-member 120. The left-right length of the third sub-member 130 is the same as the left-right length of the second sub-member 120. It is preferable that the third sub-member 130 has a clad layer containing a brazing material formed on its surface.

The third sub-member 130 is a flat plate-like member that extends in the vertical and horizontal directions. A plurality of diversion openings 132 are formed in the third sub-member 130. The diversion openings 132 are an example of an opening in the first plate in the claims. Note that in Figure 7, a cross-sectional view of the third sub-member 130 cut along the first direction D1 at a position in the stage direction where the diversion openings 132 are formed is drawn.

The multiple diversion openings 132 are arranged in a line in the vertical direction. The multiple diversion openings 132 penetrate the third sub-member 130 in the plate thickness direction (first direction D1). In this embodiment, the shape of the diversion openings 132 when viewed along the first direction D1 is rectangular. However, the shape of the diversion openings 132 when viewed along the first direction D1 may be other than rectangular, such as circular. In order to ensure a sufficient amount of refrigerant flowing through the diversion openings 132, it is preferable that the width Wo of the diversion openings in the thickness direction of the flat tube 28 (see FIG. 6) is 1 mm or more. When viewed from the rear, each diversion opening 132 at least partially overlaps with each communication hole 122a of the second sub-member 120, and is in a state of communication with each other.

The position and size of each diversion opening 132 in the left-right direction (width direction of the flat tube 28) will be described later.

The third sub-member 130 is a member disposed between the aforementioned first spaces S1 and the second space S2 described later. The second spaces S2 are formed for each of the first portion 42a to the fifth portion 42e of the first header 40 (in the example shown in FIG. 5, five second spaces S2 are formed in the first header 40). Each second space S2 is adjacent to a predetermined number of first spaces S1, two or more, in the first direction D1, separated by the third sub-member 130. The number of first spaces S1 adjacent to each second space S2 separated by the third sub-member 130 may be the same or different. Each second space S2 is a space into which the refrigerant flows from the liquid refrigerant pipe 20 through the diverter 22, the corresponding diverter pipes 22a to 22e, and the connecting pipes 49a to 49e when the first heat exchanger 11 is used as an evaporator.

Each of the diversion openings 132 of the third sub-member 130 is an opening that connects the first space S1 and the second space S2. At least one diversion opening 132 is provided for each first space S1. When the first heat exchanger 11 functions as an evaporator, the refrigerant flowing from the liquid refrigerant tube 20 into the second space S2 is divided into multiple diversion openings 132 that open into the second space S2, and flows into the first space S1 corresponding to each diversion opening 132.

(4-6-4) Fourth sub-member The fourth sub-member 140 is a member that is laminated so as to be in contact with the front surface of the third sub-member 130. The left-right length of the fourth sub-member 140 is the same as the left-right length of the third sub-member 130. A clad layer having a brazing material may be formed on the surface of the fourth sub-member 140.

The fourth sub-member 140 has a flat plate shape that is wide in the vertical and horizontal directions. The fourth sub-member 140 has one first penetration portion 142 formed for each of the first portion 42a to the fifth portion 42e of the first header 40.

Each first penetration portion 142 is an opening formed in the center of the fourth sub-member 140 in the left-right direction so as to penetrate the fourth sub-member 140 in the plate thickness direction (first direction D1). Each first penetration portion 142 includes an introduction portion 142a, a nozzle portion 142b, and an ascending portion 142c. The introduction portion 142a, the nozzle portion 142b, and the ascending portion 142c are provided in the center of the fourth sub-member 140 in the left-right direction so as to be aligned vertically in this order from the bottom up. The introduction portion 142a of the first penetration portion 142 is wider in the left-right direction than the nozzle portion 142b and the ascending portion 142c of the first penetration portion 142. The width of the ascending portion 142c of the first penetration portion 142 is wider than the nozzle portion 142b of the first penetration portion 142. In FIG. 7, a cross-sectional view of the fourth sub-member 140 is drawn taken along the first direction D1 at the position where the rising portion 142c of the first penetrating portion 142 is located in the step direction.

The fourth sub-member 140 is sandwiched between the front surface of the third sub-member 130 and the rear surface of the fifth sub-member 150 described later. The rising portion 142c of the first penetration portion 142 of the fourth sub-member 140, which is sandwiched between the front surface of the third sub-member 130 and the rear surface of the fifth sub-member 150 described later, functions as the second space S2 in the claims. The third sub-member 130, the fourth sub-member 140, and the fifth sub-member 150 constitute the second member 100b that forms the second space S2. In addition, in the second direction D2, the width W1 of the first space S1 is preferably larger than the width W2 of the second space S2, as shown in FIG. 7.

The inlet 142a of the first through-hole 142 faces the front surface of the third sub-member 130, and does not overlap the diversion opening 132 when viewed from the rear, and the space formed by the inlet 142a of the first through-hole 142 does not directly communicate with the diversion opening 132. When viewed from the rear, the inlet 142a of the first through-hole 142 overlaps with the second communication opening 152c of the fifth sub-member 150 described later, and communicates with the second communication opening 152c. Since the rear side of the inlet 142a of the first through-hole 142 is closed by the third sub-member 130, the gas-phase refrigerant and liquid-phase refrigerant that flow into the inlet 142a of the first through-hole 142 are mixed when they come into contact with the third sub-member 130, and the refrigerant in a mixed state of gas-phase refrigerant and liquid-phase refrigerant is sent to the nozzle portion 142b of the first through-hole 142.

The nozzle portion 142b of the first through-portion 142 faces the front surface of the third sub-member 130, and does not overlap the diversion opening 132 when viewed from the rear, and does not communicate with the diversion opening 132. The nozzle portion 142b of the first through-portion 142 faces the rear surface of the fifth sub-member 150 described later, and does not overlap the second communication opening 152c, the return opening 152a, and the forward opening 152b described later when viewed from the rear, and does not directly communicate with the second communication opening 152c, the return opening 152a, and the forward opening 152b. When the first heat exchanger 11 functions as an evaporator, the refrigerant that flows into the introduction portion 142a of the first through-portion 142 is accelerated as it passes through the nozzle portion 142b of the first through-portion 142, and flows into the rising portion 142c of the first through-portion 142. In other words, when the first heat exchanger 11 functions as an evaporator, the nozzle portion 142b of the first through-hole 142 blows the refrigerant that has flowed into the inlet portion 142a of the first through-hole 142 up into the rising portion 142c of the first through-hole 142.

The rising portion 142c of the first penetration portion 142 (in other words, the second space S2 surrounded by the front surface of the third sub-member 130, the rear surface of the fifth sub-member 150, and the left and right edges of the rising portion 142c of the first penetration portion 142) faces the front surface of the third sub-member 130, overlaps with the multiple diversion openings 132 when viewed from the rear, and is in communication with the multiple diversion openings 132. The manner in which the diversion openings 132 overlap with the second space S2 will be described later.

The rising portion 142c of the first through portion 142 faces the front surface of the fifth sub-member 150 (described later), and does not overlap with the second communication opening 152c when viewed from the rear, but overlaps with the return opening 152a and the forward opening 152b. The roles of the return opening 152a and the forward opening 152b will be described later.

The rising portion 142c of the first through portion 142 is sandwiched between the front surface of the third sub-member 130 and the rear surface of the fifth sub-member 150 described later, thereby forming a main space Sa surrounded by the front surface of the third sub-member 130, the rear surface of the fifth sub-member 150 described later, and the left and right edges of the rising portion 142c of the first through portion 142. The main space Sa is a space through which the refrigerant moves so as to be blown up along the longitudinal direction of the first header 40 when the first heat exchanger 11 is used as an evaporator. When the first heat exchanger 11 is used as an evaporator, the nozzle portion 142b of the first through portion 142 functions as a refrigerant inlet, and the forward opening 152b of the fifth sub-member 150 functions as a refrigerant outlet. When the first heat exchanger 11 is used as an evaporator, the refrigerant that flows into the main space Sa from the nozzle portion 142b of the first through-hole 142 as a refrigerant inlet moves to the forward opening 152b of the fifth sub member 150 while being diverted to a plurality of diverting openings 132. The refrigerant that moves to the forward opening 152b of the fifth sub member 150 without being diverted to the diverting opening 132 flows into the sub space Sb described below. The refrigerant that flows into the sub space Sb (the refrigerant that reaches the forward opening 152b of the fifth sub member 150, which is the refrigerant outlet of the main space Sa) moves downward in the sub space Sb and is guided from the return opening 152a of the fifth sub member 150 to the vicinity of the nozzle portion 142b of the first through-hole 142, which is the refrigerant inlet of the main space Sa. The main space Sa here is the same space as the second space S2 in the claims.

The connection pipes 49a-49e that supply refrigerant to the inlet portion 142a of the first through-hole 142 when the first heat exchanger 11 is used as an evaporator are at the same height as the inlet portion 142a of the corresponding first through-hole 142 (provided in the portion 42a-42e having the sub-space 23a-23e to which the connection pipes 49a-49e supply refrigerant), and are connected to the seventh sub-member 170 described later at the center position in the left-right direction of the inlet portion 142a. Also, the center of the inlet portion 142a in the left-right direction of each first through-hole 142 is aligned in a straight line in the vertical direction with the center of the nozzle portion 142b and the center of the rising portion 142c in the left-right direction of each first through-hole 142. Therefore, the refrigerant that flows through the connection pipes 49a to 49e flows into the center of the introduction portion 142a in the left-right direction through the connection opening 172, the first communication opening 174a, and the second communication opening 152c described below, and is blown vertically upward from the introduction portion 142a through the nozzle portion 142b toward the rising portion 142c without moving in the left-right direction or without moving much in the left-right direction. This configuration makes it easier to suppress the occurrence of a phenomenon in which the refrigerant is supplied unevenly in the left-right direction from the nozzle portion 142b of the first penetration portion 142 to the main space Sa (second space S2).

(4-6-5) Fifth sub-member The fifth sub-member 150 is a member that is laminated so as to be in contact with the front surface of the fourth sub-member 140. The left-right length of the fifth sub-member 150 is the same as the left-right length of the fourth sub-member 140. It is preferable that the fifth sub-member 150 has a clad layer containing a brazing material formed on its surface.

The fifth sub-member 150 has a flat plate shape that is wide in the vertical and horizontal directions. In the fifth sub-member 150, one second communication opening 152c, one return opening 152a, and one forward opening 152b are formed for each of the first portion 42a to the fifth portion 42e of the first header 40. The second communication opening 152c, the return opening 152a, and the forward opening 152b are independent openings that are formed at positions separated from each other in the vertical direction (stage direction). The second communication opening 152c, the return opening 152a, and the forward opening 152b are all openings that penetrate the fifth sub-member 150 in the plate thickness direction (first direction D1). In addition, in FIG. 7, a cross-sectional view of the fifth sub-member 150 is drawn along the first direction D1 at a position in the step direction where the second communication opening 152c, the return opening 152a, and the forward opening 152b do not exist.

When viewed from the rear, the second communication opening 152c overlaps with the introduction portion 142a of the first penetration portion 142 of the fourth sub-member 140, and they are in communication with each other. When viewed from the rear, the second communication opening 152c overlaps with the first communication opening 162a of the sixth sub-member 160, which will be described later, and they are in communication with each other. When viewed from the rear, the second communication opening 152c does not overlap with the nozzle portion 142b and the rising portion 142c of the first penetration portion 142 of the fourth sub-member 140, and they are not in direct communication with each other. When viewed from the rear, the second communication opening 152c does not overlap with the descending opening 162b of the sixth sub-member 160, which will be described later, and they are not in communication with each other.

When viewed from the rear, the return opening 152a overlaps with the rising portion 142c (second space S2) of the first penetrating portion 142 of the fourth sub-member 140 near the lower end of the rising portion 142c of the first penetrating portion 142 (near the nozzle portion 142b of the first penetrating portion 142), and is in communication with the rising portion 142c near the lower end (near the refrigerant inlet of the second space S2).

When viewed from the rear, the forward opening 152b overlaps with the portion near the upper end of the rising portion 142c of the first through portion 142 of the fourth sub-member 140, and is in communication with the portion near the upper end of the rising portion 142c. The forward opening 152b functions as a refrigerant outlet for the main space Sa described above.

(4-6-6) Sixth sub member The sixth sub member 160 is a member that is laminated so as to face and be in contact with the front surface of the fifth sub member 150. The left-right length of the sixth sub member 160 is the same as the left-right length of the fifth sub member 150. The sixth sub member 160 may have a clad layer having a brazing material formed on its surface.

The sixth sub-member 160 has a flat plate shape that is wide in both the vertical and horizontal directions. The sixth sub-member 160 has one first communication opening 162a and one descending opening 162b formed for each of the first portion 42a to the fifth portion 42e of the first header 40.

The first communication opening 162a and the descending opening 162b are independent openings formed at positions separated in the up-down direction (step direction). The first communication opening 162a and the descending opening 162b are both openings that penetrate the sixth sub-member 160 in the plate thickness direction (first direction D1). Note that in Figure 7, a cross-sectional view of the sixth sub-member 160 cut along the first direction D1 at the position where the descending opening 162b is located in the step direction is drawn.

When viewed from the rear, the first communication opening 162a overlaps with the second communication opening 152c of the fifth sub-member 150, and is in communication with the second communication opening 152c. Also, when viewed from the rear, the first communication opening 162a overlaps with the connection opening 172 of the seventh sub-member 170 (described below), and is in communication with the connection opening 172.

When viewed from the rear, the descending opening 162b overlaps with the return opening 152a and the forward opening 152b of the fifth sub-member 150, and is in communication with the return opening 152a and the forward opening 152b. When viewed from the rear, the descending opening 162b does not overlap with the connection opening 172 of the seventh sub-member 170 (described later), and they are not in direct communication with each other.

The descending opening 162b is sandwiched between the front surface of the fifth sub member 150 and the rear surface of the seventh sub member 170, forming a sub space Sb surrounded by the front surface of the fifth sub member 150, the rear surface of the seventh sub member 170, and the left and right edges of the first communication opening 162a of the sixth sub member 160. As described above, the sub space Sb guides the refrigerant that has reached the refrigerant outlet (the forward opening 152b of the fifth sub member 150) of the main space Sa (the second space S2) to the vicinity of the nozzle portion 142b of the first through portion 142, which serves as the refrigerant inlet of the main space Sa. The refrigerant guided from the sub space Sb to the main space Sa moves upward toward the forward opening 152b of the fifth sub member 150 while being diverted to the multiple diverting openings 132 together with the refrigerant flowing into the main space Sa from the nozzle portion 142b of the first through portion 142.

(4-6-7) Seventh sub-member The seventh sub-member 170 is a member that is laminated so as to face and be in contact with the front surface of the sixth sub-member 160. The left-right length of the seventh sub-member 170 is the same as the left-right length of the sixth sub-member 160. It is preferable that the seventh sub-member 170 has a clad layer containing a brazing material formed on its surface.

The seventh sub-member 170 has a flat plate shape that is wide in both the vertical and horizontal directions. The seventh sub-member 170 has one connection opening 172 formed for each of the first portion 42a to the fifth portion 42e of the first header 40. The connection opening 172 is an opening that penetrates the seventh sub-member 170 in the plate thickness direction (first direction D1). Note that in Figure 7, a cross-sectional view of the seventh sub-member 170 cut along the first direction D1 at the position where the connection opening 172 is located in the row direction is drawn.

When viewed from the rear, the connection opening 172 overlaps with a portion of the first communication opening 162a of the sixth sub-member 160, and is in communication with the first communication opening 162a. When viewed from the rear, the connection opening 172 does not overlap with the descending opening 162b of the sixth sub-member 160, and is not in direct communication with the descending opening 162b.

The connection opening 172 formed in the seventh sub-member 170 is an opening into which one of the connection pipes 49a to 49e (connection pipe 49) is inserted and connected. When the first heat exchanger 11 functions as a refrigerant evaporator, the refrigerant flowing through each of the connection pipes 49a to 49e is sent to the introduction portion 142a of the first through portion 142 via the first communication opening 162a of the sixth sub-member 160 and the second communication opening 152c of the fifth sub-member 150.

(5) Flow of Refrigerant in the First Header when the First Heat Exchanger Functions as an Evaporator The flow of refrigerant in the first header 40 when the first heat exchanger 11 functions as an evaporator of the refrigerant will be described.

The liquid refrigerant or the refrigerant in a two-phase gas-liquid state that is divided into the multiple flow dividing pipes 22a-22e in the flow dividing device 22 flows through the corresponding connection pipes 49a-49e, passes through the connection opening 172 of the seventh sub-member 170, and flows into the portions 42a-42e (each of the sub-spaces 23a-23e) of the first header 40.

Below, the flow of refrigerant in the first portion 42a of the first header 40 will be described with reference to FIG. 8. FIG. 8 is a schematic diagram showing the flow of refrigerant in the first portion 42a of the first header 40 when the first heat exchanger 11 functions as a refrigerant evaporator. Note that, although not described here, the flow of refrigerant in the second portion 42b to the fifth portion 42e of the first header 40 will not be described.

The refrigerant that flows through the connecting pipe 49a passes through the connecting opening 172 provided for the first portion 42a, and flows into the first communication opening 162a also provided for the first portion 42a. The refrigerant that flows into the first communication opening 162a passes through the second communication opening 152c provided for the first portion 42a, and flows into the introduction portion 142a of the first penetration portion 142 of the fourth sub-member 140 provided for the first portion 42a.

The refrigerant that flows into the introduction portion 142a of the first through-hole 142 is accelerated when passing through the nozzle portion 142b of the first through-hole 142 as the refrigerant inlet of the main space Sa, and rises in the rising portion 142c (main space Sa, second space S2) of the first through-hole 142 (see FIG. 8). Since the width of the rising portion 142c in the left-right direction is narrower than that of the introduction portion 142a, even when the amount of refrigerant circulating in the refrigerant circuit 6 is small, the refrigerant that flows into the main space Sa can easily reach the branch opening 132 located near the upper end of the main space Sa. The refrigerant that flows into the main space Sa flows toward the upper end of the main space Sa while branching into each branch opening 132 (see FIG. 8). The refrigerant that flows into each branch opening 132 flows into the corresponding first space S1 and flows through the flat tube 28 inserted in the first space S1. The refrigerant that reaches the vicinity of the upper end of the main space Sa passes through the forward opening 152b of the fifth sub member 150 as the refrigerant outlet of the main space Sa and flows into the downward opening 162b (sub-space Sb) (see FIG. 8). The refrigerant that reaches the sub-space Sb descends and is returned through the return opening 152a to the vicinity of the lower part of the main space Sa and to the vicinity of the nozzle part 142b of the first through-portion 142 as the refrigerant inlet of the main space Sa (the space above the nozzle part 142b of the first through-portion 142). In this way, since the refrigerant can be circulated by the main space Sa (second space S2), the forward opening 152b, the sub-space Sb, and the return opening 152a, even if some of the refrigerant does not flow because it branches into any of the branch openings 132 when it flows upward in the main space Sa, it can be returned to the main space Sa again through the sub-space Sb, so that drift in the flat tubes 28 is easily suppressed.

(6) Arrangement of Flow Diversion Openings The arrangement of the flow diversion openings 132 for suppressing drift of flow to the flat tubes 28 when the first heat exchanger 11 is used as an evaporator will be described below.

First, referring to FIG. 9, we will explain the problems that arise when, as in conventional heat exchangers, openings are arranged only in the center of the second space S2 in which the refrigerant is present in the width direction (second direction D2) of the flat tubes 28 when viewed along the insertion direction (first direction D1) of the flat tubes 28 into the first space S1, and the refrigerant is diverted from the second space S2 to the first space S1.

In FIG. 9, member A corresponding to the third sub-member 130 is shown as viewed along the first direction D1, and member A is drawn with a solid line. The circle drawn with a solid line is an opening Op corresponding to the diversion opening 132 formed in the third sub-member 130. However, unlike the diversion opening 132 described in detail later, in FIG. 9, opening Op is provided in the center of the second space S2 in the second direction D2, which is the width direction of the flat tube 28. Also, in FIG. 9, the first through portion 142 of the fourth sub-member 140 is drawn with a dashed line.

For example, if the dryness of the refrigerant flowing into the second space S2 is relatively low (if the amount of gas phase refrigerant is small), the refrigerant flow in the second space S2 tends to be dominated by bubble flow and slug flow, and even if the opening Op is formed in the position shown in Figure 9, drift toward the flat tubes 28 is relatively unlikely to be a problem.

On the other hand, if the dryness of the refrigerant flowing into the second space S2 is relatively high (if the amount of gas phase refrigerant is large), the refrigerant flow in the second space S2 is likely to be dominated by churn flow and annular flow. In this case, as shown in Figure 9, the liquid phase refrigerant tends to flow near the ends in the left and right direction of the second space S2, as depicted by the diagonal hatching, and therefore, among the openings Op that open into the first second space S2, the openings Op located at both ends in the row direction tend to have a relatively large amount of liquid phase refrigerant, and the openings Op located in the center in the row direction tend to have a relatively small amount of liquid phase refrigerant, which can easily cause problems with drift.

For example, when using a refrigerant with a small global warming potential, such as R290 or _CO2, which is increasingly being adopted from the viewpoint of environmental conservation, operating conditions are often selected such that a refrigerant with a high dryness fraction flows into the first heat exchanger 11. Therefore, when using R290 or _CO2 as a refrigerant, a problem of drift is likely to occur.

In addition, when using refrigerants with low global warming potential such as R290 or CO2, the gas density is smaller than conventional refrigerants such as R32 or R410A, so the pressure loss in the heat exchanger is likely to be large. Furthermore, since R290 has a large gas-liquid velocity difference, the flat tubes that communicate with the openings Op located in the center in the row direction, among the openings Op that open into the second space S2 of 1, are particularly susceptible to overheating, which can easily cause problems with reduced performance.

In addition, when the heat exchanger becomes larger and the amount of refrigerant circulating through each section of the heat exchange section becomes smaller, the pressure loss in the header accounts for a larger proportion of the total pressure loss of the heat exchanger, and the variation in header pressure loss becomes dominant, which can easily lead to drift and reduced performance.

In consideration of these problems, in the first heat exchanger 11 of the present disclosure, when viewed along the insertion direction (first direction D1) of the flat tube 28 into the first space S1, the diversion opening 132 is at least partially adjacent to one end 144 of the second space S2 in the width direction (second direction D2) of the flat tube 28.

Note that the end 144 of the second space S2 refers to the position of the inner edge in the left-right direction (second direction D2) of the rising portion 142c of the first penetrating portion 142 of the fourth sub-member 140 that forms the second space S2 (see Figure 7).

Furthermore, when the diversion opening 132 is at least partially adjacent to one end 144 of the second space S2 in the width direction (second direction D2) of the flat tube 28, this means that a portion of the diversion opening 132 is present within a range of length L in the second direction D2 in the direction from one end 144 toward the other end 144.

The present inventors have found that the above-mentioned drift is easily suppressed by providing a diversion opening 132 at least partially between the end 144 of the second space S2 and a position 15% of the width W2 inward from the end 144 into the second space S2 in the second direction D2 (by setting the above-mentioned length L to 15% of the width W2). In other words, the inventors have found that the above-mentioned drift is easily suppressed by overlapping at least a portion of the area between the end 144 of the second space S2 and a position 15% of the width W2 inward from the end 144 into the second space S2 with at least a portion of the diversion opening 132 in the second direction D2. Furthermore, the present inventors have found that the above-mentioned drift is particularly easily suppressed by providing a diversion opening 132 at least partially between the end 144 of the second space S2 and a position 10% of the width W2 inside the second space S2 from the end 144 in the second direction D2 (by setting the length L to 10% of the width W2).

Examples of the arrangement of the diversion openings 132 are explained using Figures 10 to 13.

Figure 10 is a schematic diagram of the interior of the first header 40 viewed in the longitudinal direction of the first header 40 (schematic diagram viewed from above), depicting a first example of the arrangement of the first space S1, the second space S2, and the diversion openings 132 of the third sub-member 130. Figure 11 is a schematic diagram of the first header 40 viewed in the longitudinal direction (schematic diagram viewed from above), depicting a second example of the arrangement of the first space S1, the second space S2, and the diversion openings 132 of the third sub-member 130. Figure 12 is a schematic diagram of the first header 40 viewed in the longitudinal direction (schematic diagram viewed from above), depicting a third example of the arrangement of the first space S1, the second space S2, and the diversion openings 132 of the third sub-member 130. FIG. 13 is a schematic diagram of the first header 40 viewed in the longitudinal direction (schematic diagram viewed from above), illustrating a fourth example of the arrangement of the first space S1, the second space S2, and the diversion openings 132 of the third sub-member 130.

In addition, in Figures 10 to 13, the area hatched with diagonal lines slanting upwards to the right represents the second space S2, the area hatched with diagonal lines slanting downwards to the right represents the first space S1, and the area hatched with dots depicts the position of the diversion opening 132.

In the example of Figure 10, when viewed along the first direction D1, the diversion opening 132 partially overlaps one end 144 of the second space S2 in the second direction D2. Note that the diversion opening 132 partially overlapping one end 144 of the second space S2 in the second direction D2 means that the diversion opening 132 is present at the position of one end 144 in the second direction D2. In particular, in the example of Figure 10, the diversion opening 132 partially overlaps both ends 144 of the second space S2 in the second direction D2. Furthermore, in the example of Figure 10, when viewed along the first direction D1, the diversion opening 132 overlaps the entire second space S2 in the second direction D2. In other words, when viewed along the first direction D1, the diversion opening 132 overlaps both ends 144 of the second space S2 in the second direction D2, and the width of the diversion opening 132 in the second direction D2 is greater than or equal to the width of the second space S2 in the second direction D2.

In a second example (see FIG. 11) different from the examples depicted in FIG. 7 and FIG. 10, the diversion opening 132 is at least partially adjacent to both ends 144 in the second direction D2. For example, in the second example, the diversion opening 132 is at least partially provided between both ends 144 of the second space S2 and a position 15% of the width W2 inward from each end 144 into the second space S2 in the second direction D2.

Furthermore, in a third example (see FIG. 12), there are multiple (e.g., two in the example of FIG. 12) diversion openings 132 that communicate between the second space S2 and one first space S1. In the example of FIG. 12, when viewed along the first direction D1, each diversion opening 132 partially overlaps one end 144 of the second space S2 in the second direction D2. In other words, a pair of diversion openings 132 partially overlaps both ends 144 in the second direction D2.

In yet another fourth example (see FIG. 13), there are a plurality of (for example, two in the example of FIG. 12) diversion openings 132 that communicate between the second space S2 and one first space S1. In the example of FIG. 12, when viewed along the first direction D1, one diversion opening 132 partially overlaps one end 144 of the second space S2 in the second direction D2, and the other diversion opening 132 is at least partially adjacent to one end 144 in the second direction D2. For example, in the fourth example, the diversion openings 132 are also provided at least partially between both end portions 144 of the second space S2 and a position 15% of the width W2 inside the second space S2 from each end portion 144 in the second direction D2.

Although not shown in the figure, for example, there may be three or more diversion openings 132 that connect the second space S2 to one first space S1, and at least one of the diversion openings 132 may not be adjacent to either of the two ends 144 in the second direction D2.

Although not shown in the figures, for example, there may be one diversion opening 132 connecting the second space S2 and one first space S1, and this diversion opening 132 may be adjacent to or overlap only one of the two ends 144 in the second direction D2.

Furthermore, it is assumed here that the diversion openings 132 of the same shape are formed at the same positions in the second direction D2 for all first spaces S1, but this is not limited to the above. The diversion openings 132 may be formed at different positions in the second direction D2 for each first space S1, and/or the diversion openings 132 of different shapes may be formed.

(7) Features of the first heat exchanger and air conditioning device of the present embodiment (7-1)
The first heat exchanger 11 of the present embodiment includes a plurality of flat tubes 28 and a first header 40 as an example of a header. The first header 40 includes a first member 100a, a second member 100b, and a third sub-member 130 as a first plate. The first member 100a forms a plurality of first spaces S1 into which the flat tubes 28 are inserted. The second member 100b forms a second space S2 into which the refrigerant flows. The third sub-member 130 is disposed between the first space S1 and the second space S2. The third sub-member 130 is formed with a flow-diversion opening 132. The flow-diversion opening 132 connects the first space S1 and the second space S2. The refrigerant flows from the second space S2 through the flow-diversion opening 132 into the first space S1. When viewed along the insertion direction (first direction D1) of the flat tube 28 into the first space S1, the diversion opening 132 is at least partially adjacent to one end 144 of the second space S2 in the width direction (second direction D2) of the flat tube 28.

In the first heat exchanger 11, the diversion opening 132 formed in the third sub-member 130 is positioned close to the end 144 of the second space S2, so that the liquid refrigerant that tends to flow near the end 144 of the second space S2 in the second direction D2 is easily distributed evenly to the multiple first spaces S1.

(7-2)
In the first heat exchanger 11 of this embodiment, when viewed along the first direction D1, the flow diversion opening 132 is at least partially adjacent to both ends 144 of the second space S2 in the second direction D2.

In the first heat exchanger 11, the diversion openings 132 formed in the third sub-member 130 are positioned close to both ends 144 of the second space S2, so that the liquid refrigerant that tends to flow near the ends 144 of the second space S2 in the second direction D2 of the flat tubes 28 is easily distributed evenly to the multiple first spaces S1.

(7-3)
In the first heat exchanger 11 of the present embodiment, the width of the second space S2 is a width W2 (a first width in the claims). In the second direction D2, the flow dividing opening 132 is at least partially provided between an end 144 of the second space S2 and a position 15% of the width W2 inward from the end 144 into the second space S2.

In the first heat exchanger 11, the liquid refrigerant that easily flows near the end 144 of the second space S2 in the width direction (second direction D2) of the flat tubes 28 is easily distributed evenly among the multiple first spaces. Therefore, there is little difference between the amount of liquid refrigerant and the amount of gas refrigerant flowing through each flat tube 28 of the first header.

(7-4)
In the first heat exchanger 11 of this embodiment (shown in Figures 10, 12 and 13), when viewed along the first direction D1, the diversion opening 132 partially overlaps one end 144 of the second space S2 in the second direction D2.

In this first heat exchanger 11, the flow dividing opening 132 formed in the third sub-member 130 is positioned to overlap the end 144 of the second space S2, so that the liquid refrigerant that tends to flow near the end 144 of the second space S2 in the second direction D2 of the flat tubes 28 is easily distributed evenly to the multiple first spaces S1.

(7-5)
In the first heat exchanger 11 of this embodiment (shown in Figures 10 and 12), when viewed along the first direction D1, the diversion opening 132 partially overlaps with both ends 144 of the second space S2 in the second direction D2.

In this first heat exchanger 11, the flow dividing openings 132 formed in the third sub-member 130 are positioned to overlap both ends 144 of the second space S2, so that the liquid refrigerant flowing through the ends 144 of the second space S2 in the second direction D2 of the flat tubes 28 is easily distributed evenly among the multiple first spaces S1.

(7-6)
In the first heat exchanger 11 of this embodiment (shown in FIG. 10), when viewed along the first direction D1, the flow dividing opening 132 overlaps with the entire second space S2 in the second direction D2.

In this first heat exchanger 11, the liquid refrigerant flowing through the ends of the second space S2 in the second direction D2 of the flat tubes 28 is easily distributed evenly among the multiple first spaces S1.

(7-7)
In the first heat exchanger 11 of this embodiment, when viewed along the first direction D1, the second member 100b forms a main space Sa and a sub-space Sb. The main space Sa has a refrigerant inlet (nozzle portion 142b of the first through portion 142) and a refrigerant outlet (outgoing opening 152b). In the main space Sa, the refrigerant moves from the refrigerant inlet to the refrigerant outlet. The sub-space Sb guides the refrigerant that has reached the refrigerant outlet of the main space Sa to the vicinity of the refrigerant inlet of the main space Sa. The flow dividing opening 132 communicates with the main space Sa as the second space S2.

The first heat exchanger 11 employs a loop structure with a main space Sa and a sub-space Sb for dividing the refrigerant, which makes it particularly easy for the refrigerant to be distributed evenly among the multiple first spaces S1.

(7-8)
In the first heat exchanger 11 of the present embodiment, the width W1 of the first space S1 in the second direction D2 is larger than the width W2 of the second space S2.

In the first heat exchanger 11, by making the width W1 of the first space S1 larger than the width W2 of the second space S2, it is easy to divert the liquid refrigerant flowing through the end 144 of the second space S2 into the first space S1 evenly through the diversion opening 132 of the third sub-member 130.

However, the width W1 of the first space S1 may be less than or equal to the width W2 of the second space S2.

(7-9)
In the first heat exchanger 11 of the present embodiment, the width Wo of the flow dividing opening 132 in the thickness direction of the flat tube 28 is 1 mm or more.

In the first heat exchanger 11, the width of the diversion opening 132 in the thickness direction of the flat tube 28 is set to 1 mm or more, which can prevent the occurrence of problems that make it difficult for the liquid refrigerant to flow through the diversion opening 132.

(7-10)
In the first heat exchanger 11 of the present embodiment, a single flat tube 28 is inserted into each of the first spaces S1. One or more flow dividing openings 132 are provided for each of the first spaces S1.

In the first heat exchanger 11, a single flat tube 28 is inserted corresponding to each first space S1, and the refrigerant from the second space S2 is guided to each first space S1 through the branch opening 132. This makes it easier to prevent unevenness in the amount of refrigerant flowing into each flat tube 28 compared to inserting multiple flat tubes 28 into each first space S1 and distributing the refrigerant that flows into each first space S1 to multiple flat tubes 28.

However, this is not limited to the above, and the first header 40 may have a structure in which multiple flat tubes 28 are inserted into one first space S1, and the refrigerant that flows into the first space S1 through the diversion opening 132 may be diverted to multiple flat tubes 28.

(7-11)
An air conditioning apparatus 1, as an example of a refrigeration cycle apparatus, includes a first heat exchanger 11 that functions as an evaporator, a compressor 8 that compresses a refrigerant, second heat exchangers 32a, 32b that serve as radiators that cool the refrigerant discharged from the compressor 8, and expansion devices (first expansion mechanism 12, second expansion mechanism 31a, second expansion mechanism 31b) that expand the refrigerant that flows from the radiators to the first heat exchanger 11.

In the air conditioning device 1, unevenness in the amount of refrigerant flowing into each flat tube 28 of the first heat exchanger 11 is easily suppressed, resulting in a highly efficient air conditioning device.

(8) Modifications Modifications of the above embodiment will be described below. The modifications described below may be combined as appropriate as long as they are not inconsistent with each other.

(8-1) Modification A
In the above embodiment, a description has been given of the first heat exchanger 11 in which the refrigerant flows from one side to the other side through the heat exchange section 27. However, when the first heat exchanger is used as an evaporator, as long as the header portion that distributes the liquid phase or two-phase gas-liquid refrigerant to the flat tubes 28 has a configuration as in the above embodiment, the first heat exchanger may be a heat exchanger in which the refrigerant flows in a double loop through the heat exchange section 27.

For example, when using different refrigerants in the same size heat exchanger, the optimal refrigerant path differs due to differences in the refrigerant's physical properties, so depending on the refrigerant, it may be necessary to improve the flow separation performance at high dryness levels.

This section explains an example of a refrigerant path that is different from the above embodiment, and, if that refrigerant path is adopted, which parts of the header have the internal structure described in (4-6) and (6) in the above embodiment.

Note that the number of vertical sections of the heat exchange section 27 of each first heat exchanger, the number of flat tubes 28 included in each section of the heat exchange section 27, the way the refrigerant flows in the heat exchange section 27, etc. shown in the following examples are merely examples for explanatory purposes and do not limit the present disclosure.

In the first heat exchanger 11A of the example of Figures 14 and 15, the second header 70A is partitioned into two upper and lower parts 70Aa, 70Ab. A connecting tube 19a to which the first gas refrigerant tube 19 is connected is connected to part 70Aa. A connecting tube 20a to which the liquid refrigerant tube 20 is connected is connected to part 70Ab. The heat exchange section 27 is partitioned into four heat exchange sections 27a to 27d. The heat exchange sections 27a, 27b are connected to part 70Aa of the second header 70A. The heat exchange sections 27c, 27d are connected to part 70Ab of the second header 70A. The first header 40A is vertically divided into four parts 42Aa to 42Ad, the same number as the heat exchange sections 27a to 27d, and each of the heat exchange sections 27a to 27d is connected to one of the corresponding parts 42Aa to 42Ad. The first header part 42Aa and the first header part 42Ac are connected by a pipe 41a. The second header part 42Aa and the first header part 42Ac are connected by a pipe 41b.

When functioning as an evaporator, the refrigerant flows in the first heat exchanger 11A as follows. First, the liquid refrigerant or two-phase refrigerant flowing through the liquid refrigerant tube 20 flows into the interior of portion 70Ab of the second header 70A via the connecting tube 20a. The refrigerant that flows into the interior of portion 70Ab of the second header 70A is diverted to the flat tubes 28 of heat exchange sections 27c and 27d. The refrigerant that flows through the flat tubes 28 of heat exchange section 27c flows into the interior of portion 42Ac of the first header 40A, and the refrigerant that flows through the flat tubes 28 of heat exchange section 27d flows into the interior of portion 42Ad of the first header 40A. The refrigerant that flows into the inside of the portion 42Ac of the first header 40A flows into the inside of the portion 42Aa of the first header 40A through the pipe 41a, and the refrigerant that flows into the inside of the portion 42Ad of the first header 40A flows into the inside of the portion 42Ab of the first header 40A through the pipe 41a. The refrigerant that flows into the inside of the portion 42Aa of the first header 40A is diverted to the flat tubes 28 of the heat exchange section 27a. The refrigerant that flows into the inside of the portion 42Ab of the first header 40A is diverted to the flat tubes 28 of the heat exchange section 27b. The refrigerant that flows through the flat tubes 28 of the heat exchange sections 27a and 27b flows into the inside of the portion 70Aa of the second header 70A, merges with it, and flows out into the first gas refrigerant tube 19 through the connecting tube 19a connected to the portion 70Aa of the second header 70A.

When configured in this manner, by adopting the internal structure of the header described in (4-6) and (6) in the above embodiment for the portion 70Ab of the second header 70A and the portions 42Aa and 42Ab of the first header 40A, the liquid refrigerant and gas refrigerant are more likely to be distributed evenly to the flat tubes 28 of the heat exchange sections 27a and 27b.

When the first heat exchanger 11A functions as an evaporator, the refrigerant that has undergone heat exchange in the heat exchange sections 27c and 27d flows into the sections 42Aa and 42Ab of the first header 40A. Therefore, refrigerant with a relatively high dryness tends to flow into the sections 42Aa and 42Ab of the first header 40A. In contrast, by adopting an arrangement of distribution openings as described in (6) of the above embodiment in the sections 42Aa and 42Ab of the first header 40A (as already described, the liquid refrigerant that tends to flow near the end 144 of the second space S2 in the second direction D2 is likely to be distributed evenly among the multiple first spaces S1), the amount of liquid refrigerant and gas refrigerant flowing into the flat tubes 28 of the heat exchange sections 27a and 27b is likely to be uniform.

In addition, if the dryness of the refrigerant flowing into the portion 70Ab of the second header 70A is low and uneven flow is unlikely to occur when the refrigerant is divided, the arrangement of the distribution openings as described in (6) of the above embodiment does not need to be adopted in the portion 70Ab of the second header 70A.

Note that any structure capable of realizing the above-mentioned refrigerant flow may be appropriately adopted for the portion 70Aa of the second header 70A and the portions 42Ac and 42Ad of the first header 40A. A detailed explanation will be omitted here.

In the first heat exchanger 11B of the example of Figures 16 and 17, the second header 70B is divided vertically into five parts 70Ba to 70Be. A connecting tube 20a to which the liquid refrigerant tube 20 is connected is connected to part 70Be. Part 70Ba of the second header 70B is connected to part 70Bc of the second header 70B by piping 71a. Part 70Bb of the second header 70B is connected to part 70Bd of the second header 70B by piping 71b. The first header 40B is divided vertically into five parts 42Ba to 42Be. A connecting tube 19a to which the first gas refrigerant tube 19 is connected is connected to part 42Ba. Part 42Bb is connected to part 42Bd of the first header 40B by piping 41a. The portion 42Bc of the first header 40B is connected to the portion 42Be of the first header 40B by the pipe 41b. The heat exchange section 27 is divided into six heat exchange sections 27a to 27f. The portions 70Ba to 70Bd of the second header 70B are each connected to one corresponding heat exchange section 27a to 27d. The portion 70Be of the second header 70B is connected to two heat exchange sections 27e to 27f. The portion 42Ba of the first header 40B is connected to two heat exchange sections 27a to 27b. The portions 42Bb to 42Be of the first header 40B are each connected to one corresponding heat exchange section 27b to 27e.

When functioning as an evaporator, the refrigerant flows in the first heat exchanger 11A as follows. First, the liquid refrigerant or two-phase refrigerant flowing through the liquid refrigerant tube 20 flows into the interior of portion 70Be of the second header 70B via the connecting tube 20a. The refrigerant that flows into the interior of portion 70Be of the second header 70B is diverted to the flat tubes 28 of the heat exchange sections 27e and 27f. The refrigerant that flows through the flat tubes 28 of heat exchange section 27e flows into the interior of portion 42Bd of the first header 40B, and the refrigerant that flows through the flat tubes 28 of heat exchange section 27f flows into the interior of portion 42Be of the first header 40B. The refrigerant that has flowed into the portion 42Bd of the first header 40B flows into the portion 42Bb of the first header 40B through the pipe 41a, and the refrigerant that has flowed into the portion 42Bf of the first header 40B flows into the portion 42Bc of the first header 40B through the pipe 41b. The refrigerant that has flowed into the portion 42Bb of the first header 40B is diverted to the flat tubes 28 of the heat exchange section 27c. The refrigerant that has flowed into the portion 42Bc of the first header 40B is diverted to the flat tubes 28 of the heat exchange section 27d. The refrigerant that has flowed through the flat tubes 28 of the heat exchange section 27c flows into the portion 70Bc of the second header 70B. The refrigerant that has flowed through the flat tubes 28 of the heat exchange section 27d flows into the portion 70Bd of the second header 70B. The refrigerant that flows into the portion 70Bc of the second header 70B flows into the portion 70Ba of the second header 70B through the pipe 71a, and the refrigerant that flows into the portion 70Bd of the second header 70B flows into the portion 70Bb of the second header 70B through the pipe 71b. The refrigerant that flows into the portion 70Ba of the second header 70B is diverted to the flat tubes 28 of the heat exchanger 27a. The refrigerant that flows into the portion 70Bb of the second header 70B is diverted to the flat tubes 28 of the heat exchanger 27b. The refrigerant that flows through the flat tubes 28 of the heat exchangers 27a and 27b flows into the portion 42Ba of the first header 40B, merges with it, and flows out into the first gas refrigerant tube 19 through the connecting tube 19a connected to the portion 42Ba of the first header 40B.

When configured in this manner, by adopting the internal structure of the headers described in (4-6) and (6) in the above embodiment for the portion 70Be of the second header 70B, the portions 42Bb and 42Bc of the first header 40B, and the portions 70Ba and 70Bb of the second header 70B, the liquid refrigerant and gas refrigerant are more likely to be distributed evenly to the flat tubes 28 of the heat exchange section 27.

When the first heat exchanger 11B functions as an evaporator, the refrigerant that has undergone heat exchange in the heat exchange section 27 flows into the parts 42Bb, 42Bc of the first header 40B and the parts 70Ba, 70Bb of the second header 70B. Therefore, refrigerant with a relatively high dryness tends to flow into the parts 42Bb, 42Bc of the first header 40B and the parts 70Ba, 70Bb of the second header 70B. In contrast, by adopting the arrangement of the distribution openings as described in (6) of the above embodiment (as already described, the liquid refrigerant that tends to flow near the end 144 of the second space S2 in the second direction D2 is likely to be distributed evenly among the multiple first spaces S1), the amount of liquid refrigerant and gas refrigerant that are distributed and flow into the flat tubes 28 is likely to be uniform.

In addition, in parts such as part 70Be of the second header 70B where the dryness of the inflowing refrigerant is low and where biasing is unlikely to occur when the refrigerant is divided, the arrangement of the distribution openings as described in (6) of the above embodiment does not need to be adopted.

Note that any structure capable of realizing the above-mentioned refrigerant flow may be appropriately adopted for the portions 70Bc and 70Bd of the second header 70B and the portions 42Ba, 42Bd, and 42Bf of the first header 40B. A detailed description will be omitted here.

In summary, in the first heat exchangers 11A and 11B, the flat tubes 28 include at least a first flat tube and a plurality of second flat tubes. In the heat exchanger, the refrigerant that flows through the first flat tube passes through a first portion of the header into which the second flat tubes are inserted, and flows into the second flat tubes.

For example, in the first heat exchanger 11A, the flat tubes 28 of the heat exchange sections 27c and 27d are first flat tubes, the flat tubes 28 of the heat exchange sections 27a and 27b are multiple second flat tubes, and the portions 42Aa and 42Ab of the first header 40A are the first portion of the header.

Also, for example, in the first heat exchanger 11B, the flat tubes 28 of the heat exchange sections 27e and 27f are first flat tubes, the flat tubes 28 of the heat exchange sections 27c and 27d are a plurality of second flat tubes, and the portions 42Bb and 42Bc of the first header 40B are the first portion of the header.Also, for example, in the first heat exchanger 11B, the flat tubes 28 of the heat exchange sections 27c and 27d are also first flat tubes, in this case, the flat tubes 28 of the heat exchange sections 27a and 27d are a plurality of second flat tubes, and the portions 70Ba and 70Bb of the second header 70 are the first portion of the header.

The first part of the header of the first heat exchanger 11A, 11B preferably has the structure and configuration described in (4-6) and (6) of the above embodiment.

When a refrigerant with a large amount of liquid flows through the first flat tubes and exchanges heat, the refrigerant has a high dryness when it turns around at the header and flows into the second flat tubes. In such a case, in a conventional heat exchanger, there is a possibility that a difference will occur between the amount of liquid refrigerant and gas refrigerant flowing through each of the second flat tubes, reducing the efficiency of heat exchange.

In contrast, in the first heat exchangers 11A and 11B, the liquid refrigerant is more likely to be distributed evenly among the multiple first spaces in the first portion of the header, making it easier to equalize the amounts of liquid refrigerant and gas refrigerant flowing through each of the second flat tubes.

(8-2) Modification B
In the above embodiment, the first header 40 has been described as a header formed by stacking the first sub-member 110 to the seventh sub-member 170, but the structure of the first header 40 is not limited to this structure. For example, the first header 40 may be formed in the above structure by arranging a partition plate with appropriate openings inside a cylindrical header.

(8-3) Modification C
In the above embodiment, the main space Sa and the sub space Sb are formed in the first header 40, but this is not limited to this. For example, the first header 40 may omit the sub space Sb (does not have a loop structure in which the refrigerant circulates) and have only a structure equivalent to the main space Sa that does not communicate with the return opening 152a and the forward opening 152b.

(8-4) Modification D
In the above embodiment, an example was given in which a structure for circulating a coolant is formed by a plurality of plate-shaped portions mainly consisting of the fourth sub-member 140 to the sixth sub-member 160.

Instead of the first header 40, a first header 40A may be used that has a structure in which the refrigerant can circulate within a single plate portion rather than multiple plate portions.

Figure 18 shows an exploded perspective view of the first header 40A. Figure 19 shows a cross-sectional view of the first sub-member 110A to the sixth sub-member 160A of the first header 40A cut along the insertion direction (first direction D1) of the flat tubes 28 into the first header 40A. Note that in Figure 18, the dashed double-dashed arrows indicate the refrigerant flow when the first heat exchanger 11 functions as a refrigerant evaporator.

The first header 40A has a first sub-member 110A, a second sub-member 120A, a third sub-member 130A, a fourth sub-member 140A, a fifth sub-member 150A, and a sixth sub-member 160A.

Patent Document 1 (JP Patent Publication No. 2021-12018) also shows a structure similar to that of the first header 40A, so here we will mainly explain the main differences from the above embodiment and the differences between Patent Document 1 (JP Patent Publication No. 2021-12018) and this disclosure.

In FIG. 19, a cross-sectional view of the first sub-member 110A is drawn along the first direction D1 at the position where the flat tube connection opening (similar to the flat tube connection opening 112a of the first sub-member 110 in the first embodiment) is formed in the step direction. The function and structure of the first sub-member 110A are similar to those of the first sub-member 110 in the above embodiment, so a detailed description will be omitted.

The second sub member 120A is a flat member and has multiple first openings 122Aa formed therein. In FIG. 19, a cross-sectional view of the second sub member 120A cut along the first direction D1 at the position where the first openings 122Aa are formed in the step direction is drawn. The multiple first openings 122Aa are arranged side by side in the vertical direction (step direction) and penetrate the second sub member 120A in the plate thickness direction. The multiple first openings 122Aa are formed at positions corresponding to the flat tube connection openings 112a of the first sub member 110A in the vertical direction (step direction). Each first opening 122Aa is larger than the flat tube connection openings 112a of the first sub member 110A.

The third sub member 130A is a flat member and has multiple second openings 132Aa formed therein. In FIG. 19, a cross-sectional view of the third sub member 130A cut along the first direction D1 at the position where the second openings 132Aa are formed in the step direction is drawn. The multiple second openings 132Aa are arranged in a line in the vertical direction (step direction) and penetrate the third sub member 130A in the plate thickness direction. The multiple second openings 132Aa are formed at positions corresponding to the first openings 122Aa of the second sub member 120A in the vertical direction (step direction). The width of each second opening 132Aa is designed to be slightly narrower than the width of the flat tube 28. As a result, the flat tube 28 inserted into the flat tube connection opening 112a and passing through the first opening 122Aa comes into contact with the front surface of the third sub member 130A. This allows the position of the flat tube 28 to be adjusted. In this modified example, the flat tube 28 is inserted into the space formed by the first sub-member 110A to the third sub-member 130A. In other words, in this modified example, the first sub-member 110A to the third sub-member 130A are an example of a first member that forms the first space S1. In FIG. 18, the first member is indicated by the reference symbol "100Aa."

The fourth sub-member 140A is an example of the first plate. The fourth sub-member 140A is a flat plate-shaped member, and in FIG. 18, a plurality of diversion openings 142Aa are provided along the step direction on the left side, penetrating in the plate thickness direction, and a plurality of descending side openings 142Ab are provided on the right side, penetrating in the plate thickness direction. The function of the diversion openings 142Aa is the same as that of the diversion openings 132 in the above embodiment. The function of the descending side openings 142Ab will be described later. In FIG. 19, a cross-sectional view of the fourth sub-member 140A cut along the first direction D1 is drawn at a position where the diversion openings 142Aa are formed in the step direction and the descending side openings 142Ab are not formed.

The fifth sub member 150A is a flat member, and as shown in FIG. 18, the first through portion C1 corresponding to the first through portion 142 in the above embodiment is formed on the left side, the return opening C2 and the forward opening C3 corresponding to the return opening 152a and the forward opening 152b in the above embodiment are formed in the center in the left-right direction, and the descending opening C4 corresponding to the descending opening 162b in the above embodiment is formed on the right side in the left-right direction. In other words, in the above embodiment, the first through portion 142, the return opening 152a and the forward opening 152b, and the descending opening 162b are formed in each of the three sub members, whereas in this modified example, these are formed in the fifth sub member 150A. Note that in FIG. 19, a cross-sectional view of the fifth sub member 150A cut along the first direction D1 at the position where the first through portion C1 and the forward opening C3 are formed in the step direction is drawn.

In this first header 40A, when the first heat exchanger 11 functions as an evaporator, the refrigerant that flows into the inlet of the first through-hole C1 is blown up from the nozzle portion C1i (refrigerant inlet) of the first through-hole C1, and while being diverted to the diversion opening 142Aa, rises in the rising portion of the first through-hole C1 (in other words, the main space Sa (second space S2). The refrigerant that is not diverted to the diversion opening 142Aa and rises to the forward opening C3 (refrigerant outlet) passes through the forward opening C3 and falls into the downward opening C4 (sub-space Sb). The refrigerant flows into the lower opening C4 and moves downward. However, the lowering opening C4 is not connected to the lower end, and is a discontinuous opening. Therefore, at the discontinuous position, the refrigerant flows through the lowering side opening 142Ab provided at the corresponding position of the fourth sub-member 140A, and moves through the sub-space Sb to a position where it communicates with the return opening C2. The refrigerant that reaches the lower end of the sub-space Sb is returned through the return opening C2 to the vicinity of the refrigerant inlet of the main space Sa (the nozzle portion C1i of the first through portion C1).

The sixth sub-member 160A is a member similar to the seventh sub-member 170 of the above embodiment. The sixth sub-member 160A is provided with a connection opening 162A that penetrates in the plate thickness direction. When viewed from the rear, the connection opening 162A is positioned so as to overlap with the center in the left-right direction of the introduction portion of the first penetration portion C1.

In this embodiment, the fourth sub-member 140A to the sixth sub-member 160A function as the second member that forms the second space S2. In FIG. 18, the second member is indicated by the reference symbol "100Ab." Note that here, the fourth sub-member 140 constitutes part of the second member 100Ab and functions as the first member, but this is merely one example. The first member may be formed as a member separate from the second member 100Ab.

In the first header 40A of this modified example, when viewed along the insertion direction (first direction D1) of the flat tube 28 into the first space S1, the diversion opening 142Aa is at least partially adjacent to one end 154A of the second space S2 in the width direction (second direction D2) of the flat tube 28.

Note that the end 154A of the second space S2 refers to the position of the inner edge in the left-right direction (second direction D2) of the rising portion of the first penetration portion C1 of the fifth sub-member 150A that forms the second space S2.

Furthermore, when the diversion opening 142Aa is at least partially adjacent to one end 154A of the second space S2 in the width direction (second direction D2) of the flat tube 28, this means that a portion of the diversion opening 142Aa exists within a range of length L in the second direction D2 in the direction from one end 154A toward the other end 154A.

Here again, the present inventors have found that the above-mentioned drift is easily suppressed by at least partially providing a diversion opening 142Aa in the second direction D2 between end 154A of second space S2 and a position 15% of width W2 inward from end 154A into second space S2 (by setting the above-mentioned length L to 15% of width W2). In other words, the inventors have found that the above-mentioned drift is easily suppressed by overlapping at least a portion of the area between end 154A of second space S2 and a position 15% of width W2 inward from end 154A into second space S2 with at least a portion of diversion opening 142Aa in the second direction D2. Furthermore, the present inventors have found that the above-mentioned drift is particularly easily suppressed by providing a diversion opening 142Aa at least partially between the end 154A of the second space S2 and a position 10% of the width W2 inside the second space S2 from the end 154A in the second direction D2 (by setting the length L to 10% of the width W2).

Examples of the arrangement of the flow diversion openings 142Aa are described using Figures 20 to 22.

FIG. 20 is a schematic diagram of the inside of the first header 40A viewed in the longitudinal direction of the first header 40A (schematic diagram viewed from above), depicting a first example of the arrangement of the first space S1, the second space S2, and the flow-diversion openings 142Aa of the fourth sub-member 140. FIG. 21 is a schematic diagram of the inside of the first header 40A viewed in the longitudinal direction of the first header 40A (schematic diagram viewed from above), depicting a second example of the arrangement of the first space S1, the second space S2, and the flow-diversion openings 142Aa of the fourth sub-member 140. FIG. 22 is a schematic diagram of the inside of the first header 40A viewed in the longitudinal direction of the first header 40A (schematic diagram viewed from above), depicting a third example of the arrangement of the first space S1, the second space S2, and the flow-diversion openings 142Aa of the fourth sub-member 140.

In addition, in Figures 20 to 22, the area hatched with diagonal lines slanting upwards to the right represents the second space S2, the area hatched with diagonal lines slanting downwards to the right represents the first space S1, and the area hatched with dots depicts the position of the diversion opening 132.

In the example of FIG. 20 (as also depicted in FIG. 19), when viewed along the first direction D1, the diversion opening 142Aa overlaps both ends 154A of the second space S2 in the second direction D2, and the width of the diversion opening 142Aa in the second direction D2 is greater than or equal to the width of the second space S2 in the second direction D2.

21, when viewed along the first direction D1, the diversion opening 142Aa is adjacent to both ends 154A of the second space S2 in the second direction D2. For example, in the second example, the diversion opening 142Aa is provided at least partially between both ends 154A of the second space S2 and a position 15% of the width W2 inside the second space S2 from each end 154A in the second direction D2.

In the example of FIG. 22, there are multiple (e.g., two in the example of FIG. 17) diversion openings 142Aa that communicate between the second space S2 and one first space S1. In the example of FIG. 22, when viewed along the first direction D1, each diversion opening 142Aa partially overlaps one end 154A of the second space S2 in the second direction D2. In other words, a pair of diversion openings 142Aa partially overlap both ends 154A in the second direction D2.

As with the above embodiment, there are various variations in the arrangement of the diversion openings 142Aa.

　Although the embodiments of the present disclosure have been described above, it will be understood that various changes in form and details are possible without departing from the spirit and scope of the present disclosure as set forth in the claims.

1. Air conditioning equipment (refrigeration cycle equipment)
8 Compressor 11 First heat exchanger (heat exchanger, evaporator)
11A First heat exchanger (heat exchanger, evaporator)
11B First heat exchanger (heat exchanger, evaporator)
12 First expansion mechanism (expansion device)
28 Flat tube 31a Second expansion mechanism (expansion device)
31b Second expansion mechanism (expansion device)
32a Second heat exchanger (radiator)
32b Second heat exchanger (radiator)
40 First Header (Header)
42Aa part (first part)
42Ab part (first part)
42Bb part (first part)
42Bc part (first part)
70Ba part (first part)
70Bb part (1st part)
70 Second Header (Header)
100a First member 100b Second member 100Aa First member 100Ab Second member 130 Third sub-member (first plate)
132 Diversion opening (opening)
140A Fourth sub-member (first plate)
142b Nozzle portion (refrigerant inlet of main space)
142Aa Diversion opening (opening)
144 End 152b Outward opening (refrigerant outlet of main space)
154A End C1i Nozzle portion (refrigerant inlet of main space)
C3 Outlet opening (refrigerant outlet for main space)
D1 First direction (insertion direction)
D2 Second direction (width direction)
S1 First space S2 Second space Sa Main space Sb Sub-space W1 Width of first space W2 Width of second space (first width)
Wo Width of the flow dividing opening in the thickness direction of the flat tube

JP 2021-12018 A

Claims (12)

A plurality of flat tubes (28);
a header (40, 40A, 40B, 70B) including a first member (100a, 100Aa) that forms a plurality of first spaces (S1) into which the flat tubes are inserted, a second member (100b, 100Ab) that forms a second space (S2) into which a refrigerant flows, and a first plate (130, 140A) that is disposed between the first space and the second space;
Equipped with
The first plate has an opening (132, 142Aa) that communicates the first space with the second space and through which the refrigerant flows from the second space to the first space passes,
When viewed along the insertion direction (D1) of the flat tube into the first space, the opening is at least partially adjacent to one end (144, 154A) of the second space in the width direction (D2) of the flat tube.
Heat exchanger (11, 11A, 11B). When viewed along the insertion direction, the opening is at least partially adjacent to both ends of the second space in the width direction.
2. The heat exchanger of claim 1. The width of the second space is a first width (W2),
In the width direction, the opening is at least partially provided between an end of the second space and a position 15% of the first width from the end toward the inside of the second space.
3. A heat exchanger according to claim 1 or 2. When viewed along the insertion direction, the opening partially overlaps one end of the second space in the width direction.
A heat exchanger according to any one of claims 1 to 3. When viewed along the insertion direction, the opening partially overlaps both ends of the second space in the width direction.
5. The heat exchanger of claim 4. When viewed along the insertion direction, the opening overlaps with the entire second space in the width direction.
6. The heat exchanger according to claim 5. The second member is
a main space (Sa) having a refrigerant inlet (142b, C1i) and a refrigerant outlet (152b, C3), through which the refrigerant moves from the refrigerant inlet to the refrigerant outlet;
a sub-space (Sb) that guides the refrigerant that has reached the refrigerant outlet of the main space to the vicinity of the refrigerant inlet of the main space;
Forming
The opening communicates with the main space as the second space.
A heat exchanger according to any one of claims 1 to 6. In the width direction, the width (W1) of the first space is larger than the width (W2) of the second space.
A heat exchanger according to any one of claims 1 to 7. In the thickness direction of the flat tube, the width (Wo) of the opening is 1 mm or more.
A heat exchanger according to any one of claims 1 to 8. A single flat tube is inserted into each of the first spaces,
One or more of the openings are provided for each of the first spaces.
A heat exchanger according to any one of claims 1 to 9. The plurality of flat tubes include at least a first flat tube and a plurality of second flat tubes,
In the heat exchanger, the refrigerant that has flowed through the first flat tube passes through a first portion (42Aa, 42Ab, 42Bb, 42Bc, 70Ba, 70Bb) of the header into which the plurality of second flat tubes are inserted, and flows into the plurality of second flat tubes,
At least in the first portion of the header, when viewed along the insertion direction, the opening is at least partially adjacent to one end of the second space in the width direction.
A heat exchanger (11A, 11B) according to any one of claims 1 to 10. A heat exchanger (11, 11A, 11B) according to any one of claims 1 to 11, which functions as an evaporator;
A compressor (8) for compressing the refrigerant;
a radiator (32a, 32b) for cooling the refrigerant discharged from the compressor;
an expansion device (12, 31a, 31b) for expanding the refrigerant flowing from the radiator to the heat exchanger;
A refrigeration cycle device (1).

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