WO2024189700A1 - Heat source equipment and refrigeration cycle device - Google Patents

Abstract

This heat source equipment (2) comprises a refrigerant circuit (20), a refrigerant container (44), a connection part (43), a communication pipe (42), and a casing (41). The refrigerant circuit (20) includes a compressor (21) and a heat exchanger (23). The refrigerant container (44) is connected to the refrigerant circuit (20). The refrigerant container (44) is filled with flammable refrigerant. The connection part (43) is connected to the refrigerant container (44). The communication pipe (42) connects the connection part (43) and the refrigerant circuit (20). The casing (41) accommodates the compressor (21), the first heat exchanger (23), the refrigerant container (44), the connection part (43), and the communication pipe (42). The refrigerant container (44) is supported by a bottom plate (413) of the casing (41).

Description

Heat source equipment and refrigeration cycle equipment

　Concerning heat source equipment and refrigeration cycle equipment.

Patent document 1 (JP Patent Publication 2000-28237) discloses a refrigeration cycle device that uses a cassette-type special pressure vessel filled with the required amount of flammable refrigerant gas to fill the refrigeration cycle from the suction side piping of the compressor.

However, the above-mentioned Patent Document 1 does not disclose how to install the special pressure vessel for charging and recovering the refrigerant.

The heat source unit of the first aspect includes a refrigerant circuit, a refrigerant container, a connection portion, a connecting pipe, and a casing. The refrigerant circuit includes a compressor and a heat exchanger. The refrigerant container is connected to the refrigerant circuit. The refrigerant container is filled with a flammable refrigerant. The connection portion is connected to the refrigerant container. The connecting pipe connects the connection portion and the refrigerant circuit. The casing houses the compressor, the heat exchanger, the refrigerant container, the connection portion, and the connecting pipe. The refrigerant container is supported by a bottom plate of the casing.

In the heat source device of the first aspect, the refrigerant container filled with a flammable refrigerant is fixed to the bottom plate of the casing. This allows the refrigerant container to be stably positioned, improving safety.

The heat source machine of the second aspect is the heat source machine of the first aspect, and the connection part is provided at the bottom of the refrigerant container.

In the heat source device of the second aspect, the connection part is provided at the bottom of the refrigerant container, so that the refrigerant container is fixed to the bottom plate of the casing in such a manner that the flammable refrigerant flows from the bottom of the refrigerant container. This improves the dischargeability of the refrigeration oil contained in the refrigerant.

The heat source machine of the third aspect is the heat source machine of the second aspect, further comprising a protective member. The protective member is disposed below the refrigerant container. In addition, the protective member protects the connection portion.

In the heat source unit of the third aspect, damage to the connection can be suppressed by using protective materials.

The heat source machine of the fourth aspect is the heat source machine of the third aspect, and the connection part has a connection valve that opens and closes the connecting pipe. The protective member protects the connection valve. The protective member has an opening.

In the heat source unit of the fourth aspect, the connecting valve that opens and closes the connecting pipe connected to the refrigerant circuit can be protected by a protective member, thereby further improving safety. In addition, work can be performed through the opening in the protective member, improving workability.

The heat source machine of the fifth aspect is the heat source machine of the fourth aspect, and the opening is provided on the maintenance side.

In the heat source unit of the fifth aspect, the opening in the protective member is provided on the maintenance side, making it easy to perform maintenance on the connection parts.

The heat source machine of the sixth aspect is the heat source machine of any one of the third aspect to the fifth aspect, further comprising a base. The base is disposed on the bottom plate of the casing. The base is in contact with the protective member.

As in the heat source device of the sixth aspect, the refrigerant container may be fixed to the bottom plate of the casing via a base and a protective member.

The heat source machine of the seventh aspect is the heat source machine of the sixth aspect, in which the base is fixed to the protective member.

In the heat source device of the seventh aspect, the base placed on the bottom plate of the casing and the protective member are fixed, so that the connection part can be more appropriately protected by the protective member.

The heat source device of the eighth aspect is the heat source device of the sixth or seventh aspect, in which the base has an elastic member. The elastic member is in contact with the bottom plate.

In the heat source device of the eighth aspect, even if the refrigerant container is dropped, the elastic member can prevent damage to the refrigerant container.

The heat source machine of the ninth aspect is a heat source machine of any one of the first aspect to the eighth aspect, in which the connecting pipe has a capillary.

In the heat source device of the ninth aspect, the capillary can reduce the load applied to the connection part.

The heat source machine of the tenth aspect is the heat source machine of any one of the first aspect to the ninth aspect, further comprising a cushioning material. The cushioning material is attached to the refrigerant container.

In the heat source device of the tenth aspect, the cushioning material can protect the refrigerant container when it is subjected to an impact such as being dropped.

The heat source machine of the eleventh aspect is any one of the heat source machines of the first aspect to the tenth aspect, in which the connecting pipe is connected to the low pressure side of the refrigerant circuit.

As in the heat source unit of the eleventh aspect, the refrigerant container may be connected to the low pressure side of the refrigerant circuit via a connecting pipe and a connection part.

The refrigeration cycle device of the twelfth aspect includes a heat source machine and a user machine. The heat source machine is any one of the heat source machines of the first aspect to the eleventh aspect. The user machine is connected to the heat source machine.

The refrigeration cycle device of the twelfth aspect allows the refrigerant circuit to be filled with flammable refrigerant from a stably positioned refrigerant container, improving safety.

1 is a schematic configuration diagram of a refrigeration cycle device including a heat source unit according to an embodiment of the present disclosure. FIG. FIG. 2 is a perspective view of the refrigerant container and its vicinity in the heat source unit. In FIG. 3, the protection member and the cushioning material are omitted. FIG. 2 is a schematic diagram of the vicinity of a refrigerant container in a heat source unit.

(1) Refrigeration Cycle Apparatus As shown in Fig. 1, a refrigeration cycle apparatus 1 according to an embodiment of the present disclosure includes a heat source unit 2 and a utilization unit 3. The heat source unit 2 and the utilization unit 3 are connected to each other.

The heat source unit 2 has a refrigerant circuit 20 through which a flammable refrigerant circulates. The user unit 3 has a water circuit 30 through which water circulates. The refrigeration cycle device 1 causes the refrigerant circuit 20 to perform a vapor compression refrigeration cycle to heat or cool the water circulating through the water circuit 30, and uses this water to perform heating and cooling operations in the target space.

(2) Heat Source Unit In the following description, expressions indicating directions such as "up,""down,""front,""rear,""left," and "right" are used as appropriate, but these indicate the directions when the heat source unit 2 is installed outdoors and in normal use. In this embodiment, the up-down direction is the vertical direction.

The heat source unit 2 is placed in a space different from the target space to be heated or cooled. Here, the heat source unit 2 is installed outdoors (on the roof of a building, near the exterior wall of a building, etc.).

The heat source unit 2 includes a refrigerant circuit 20, a fan 23a, a refrigerant container 44, a connection unit 43, a connecting pipe 42, a control unit 4, and a casing 41 shown in FIG. 2. The heat source unit 2 shown in FIG. 1 further includes a portion of a water circuit 30.

(2-1) Refrigerant Circuit The refrigerant circuit 20 is a circuit through which a refrigerant circulates during normal operation such as heating operation and cooling operation. A flammable refrigerant (hereinafter also referred to as "refrigerant") is sealed in the refrigerant circuit 20 during normal operation. The flammable refrigerant is a refrigerant that has combustibility. The flammable refrigerant is, for example, a hydrocarbon refrigerant, R1234yf, R1234ze, R32, etc., and here, a refrigerant classified as highly flammable (A3) by ISO817, and is R290 (propane) in this embodiment. The refrigerant includes a refrigerating machine oil. The refrigerating machine oil is, for example, PAG (polyalkylene glycol) or the like.

The refrigerant circuit 20 includes a compressor 21, a four-way switching valve 22, a first heat exchanger 23, a pressure reducing valve 24, a second heat exchanger 25, a liquid-gas heat exchanger 26, an accumulator 27, a gas injection valve 28, and an economizer heat exchanger 29.

(2-1-1) Compressor The compressor 21 is a device for compressing a refrigerant. The compressor 21 has a suction port 21a, an injection port 21b, and a discharge port 21c. The refrigerant flows into the compressor 21 through the suction port 21a, is compressed to a high temperature and high pressure, and flows out from the discharge port 21c. The refrigerant can also flow into the compressor 21 through the injection port 21b in the middle of the compression process.

(2-1-2) Four-way switching valve The four-way switching valve 22 switches the flow of the refrigerant, so that the second heat exchanger 25 functions as an evaporator and the first heat exchanger 23 functions as a radiator during cooling operation. Also, the four-way switching valve 22 switches the flow of the refrigerant, so that the second heat exchanger 25 functions as a radiator and the first heat exchanger 23 functions as an evaporator during heating operation.

Specifically, during cooling operation, the four-way switching valve 22 connects the discharge port 21c of the compressor 21 to the first heat exchanger 23, and also connects the suction port 21a of the compressor 21 to the second heat exchanger 25. During heating operation, the four-way switching valve 22 connects the discharge port 21c of the compressor 21 to the second heat exchanger 25, and also connects the suction port 21a of the compressor 21 to the first heat exchanger 23.

(2-1-3) First Heat Exchanger The first heat exchanger 23 is an air heat exchanger. The first heat exchanger 23 exchanges heat between the refrigerant flowing inside and the outside air (outdoor air) sent from the fan 23a. As the first heat exchanger 23, a heat exchanger suitable for the application, such as a cross-fin heat exchanger or a microchannel heat exchanger, is used.

(2-1-4) Pressure Reducing Valve The pressure reducing valve 24 is an electric expansion valve. The liquid refrigerant flowing through the pressure reducing valve 24 expands to a gas-liquid two-phase state, thereby reducing the pressure and temperature of the refrigerant. The pressure reducing valve 24 controls the flow rate of the refrigerant passing through it by adjusting the valve opening.

(2-1-5) Second Heat Exchanger The second heat exchanger 25 is a water heat exchanger. In this embodiment, the second heat exchanger 25 exchanges heat between the refrigerant flowing through the refrigerant circuit 20 and the water flowing through the water circuit 30. As the second heat exchanger 25, a heat exchanger suitable for the application, such as a plate heat exchanger, is adopted.

(2-1-6) Liquid-gas heat exchanger During heating operation, the liquid-gas heat exchanger 26 exchanges heat between the high-pressure refrigerant leaving the refrigerant outlet of the second heat exchanger 25 and the low-pressure refrigerant flowing from the refrigerant outlet of the first heat exchanger 23 toward the suction port of the compressor 21.

(2-1-7) Accumulator The accumulator 27 is connected between the four-way switching valve 22 and the suction port 21a of the compressor 21. The accumulator 27 recovers the liquid refrigerant that was not gasified in the evaporator, and prevents the liquid refrigerant from flowing into the suction port 21a of the compressor 21.

(2-1-8) Gas Injection Valve The gas injection valve 28 is, for example, an on/off valve such as a solenoid valve, or a flow control valve such as an electric expansion valve. In this embodiment, the gas injection valve 28 is an electric expansion valve.

(2-1-9) Economizer Heat Exchanger The economizer heat exchanger 29 is configured to perform heat exchange between the high-temperature liquid refrigerant flowing out of the second heat exchanger 25 during heating operation and the refrigerant in a gas-liquid two-phase state flowing out of the gas injection valve 28. As a result, the liquid refrigerant from the second heat exchanger 25 is subcooled during heating operation.

A solenoid valve 32 is connected between the refrigerant flow path 31 that connects the second heat exchanger 25 and the pressure reducing valve 24 and the economizer heat exchanger 29. The solenoid valve 32 is closed during cooling operation, and the refrigerant does not flow to the economizer heat exchanger 29 or the liquid-gas heat exchanger 26.

(2-2) Fan The fan 23a flows outside air through the first heat exchanger 23. The fan 23a is driven by a fan motor.

(2-3) Casing The casing 41 shown in FIG. 2 accommodates the refrigerant circuit 20, the fan 23a, the refrigerant container 44, the connection portion 43, and the connecting pipe .

The casing 41 has a generally rectangular parallelepiped shape. Specifically, the casing 41 includes a front plate 411, a top plate 412, a bottom plate 413, and side plates 414.

The front plate 411 is a plate-like member that forms the front surface of the casing 41. An air outlet is formed in the front plate 411. The air outlet is an opening for blowing outside air taken in from the outside of the casing 41 to the inside of the casing 41 out to the outside of the casing 41.

The top plate 412 is a plate-like member that forms the upper surface of the casing 41. The bottom plate 413 is a plate-like member that forms the lower surface of the casing 41. The top plate 412 and the bottom plate 413 face each other.

The side plate 414 is a plate-like member that forms the side surface of the casing 41. The side plate has a left side plate and a right side plate. The lower portion of the side plate 414 is fixed to the bottom plate 413.

The casing 41 further includes a partition plate 415. The partition plate 415 is a plate-shaped member that extends in the vertical direction. The lower part of the partition plate 415 is fixed to the bottom plate 413 of the casing 41.

The partition plate 415 divides the inside of the casing 41 into a first chamber S1 and a second chamber S2. The first chamber S1 is an air blowing chamber, and the second chamber S2 is a machine chamber. The first chamber S1 and the second chamber S2 are each a space defined by the front plate 411, the top plate 412, the bottom plate 413, and the side plates 414 of the casing 41, and the partition plate 415.

(2-4) Communication Pipe As shown in FIG. 1, the communication pipe 42 is connected to the refrigerant circuit 20. The communication pipe 42 is brazed to the piping of the refrigerant circuit 20, for example. In the present embodiment, the communication pipe 42 is connected to the low pressure side of the refrigerant circuit 20. The low pressure side is the side in the heat source unit 2 where the pressure of the refrigerant circulating through the refrigerant circuit 20 is relatively low. In FIG. 1, the communication pipe 42 is connected between the accumulator 27 and the liquid-gas heat exchanger 26 in the refrigerant circuit 20. Since the communication pipe 42 communicates with the refrigerant piping that constitutes the refrigerant circuit 20, the refrigerant including refrigerating machine oil circulating through the refrigerant circuit 20 may flow into the communication pipe 42.

The connecting pipe 42 is a metal pipe. As shown in Figures 3 and 4, the connecting pipe 42 has a capillary 421, a first connecting pipe 422, and a second connecting pipe 423. The capillary 421, the first connecting pipe 422, and the second connecting pipe 423 are connected to each other. The outer diameters of the first connecting pipe 422 and the second connecting pipe 423 are larger than the outer diameter of the capillary 421. Here, the first connecting pipe 422 is connected to the refrigerant circuit 20. The second connecting pipe 423 is connected to the connection part 43. The capillary 421 connects the first connecting pipe 422 and the second connecting pipe 423.

1, 4, and 5, the connection part 43 is connected to the refrigerant container 44. In this embodiment, the connection part 43 connects the communication pipe 42 and the refrigerant container 44. Here, the connection part 43 communicates with the communication pipe 42 and the refrigerant container 44.

As shown in Figures 3 to 5, the connection part 43 has a connection valve 431 and a connection pipe 432. The connection valve 431 is a closing valve that opens and closes the connection pipe 42. When the connection valve 431 is opened, it communicates with the refrigerant circuit 20 via the connection pipe 42, and when the connection valve 431 is closed, it is cut off from the refrigerant circuit 20. The connection valve 431 is connected to a second connection pipe 423 and a connection pipe 432. The connection pipe 432 is connected to the refrigerant container 44. The connection pipe 432 has an inner diameter approximately the same as that of the first connection pipe 422 and the second connection pipe 423.

(2-6) Refrigerant Container The refrigerant container 44 is filled with a flammable refrigerant. In other words, the refrigerant container 44 is configured to be able to be filled with a flammable refrigerant. The refrigerant container 44 is a container that supplies the flammable refrigerant to the refrigerant circuit 20. Therefore, the flammable refrigerant filled in the refrigerant container 44 is supplied to the refrigerant circuit 20. Therefore, after the flammable refrigerant in the refrigerant container 44 is supplied to the refrigerant circuit 20, the inside of the refrigerant container 44 is not filled with the flammable refrigerant. In other words, the heat source unit 2 has a case where the refrigerant container 44 is filled with a flammable refrigerant and a case where the refrigerant container 44 is not filled with a flammable refrigerant.

As shown in Figures 2 and 5, the refrigerant container 44 is supported on the bottom plate 413 of the casing 41. In other words, the refrigerant container 44 is positioned so that a load is applied to the bottom plate 413. In this embodiment, the refrigerant container 44 is fixed to the bottom plate 413 of the casing 41 via the protective member 46 and the base 47.

As shown in FIG. 1, the refrigerant container 44 is connected to the refrigerant circuit 20. In this embodiment, the refrigerant container 44 is connected to the refrigerant circuit 20 via the connection part 43 and the communication pipe 42. Here, the refrigerant container 44 is connected to the connection part 43.

As shown in Figures 4 and 5, a connection part 43 is provided at the bottom of the refrigerant container 44. In other words, the refrigerant discharge part of the refrigerant container 44 is located below the refrigerant container 44. In other words, the refrigerant container 44 is placed upside down (upside down). Therefore, when the refrigerant filled in the refrigerant container 44 is supplied to the refrigerant circuit 20, the refrigerant filled inside flows from the bottom of the refrigerant container 44 to the refrigerant circuit 20.

The refrigerant container 44 is made of metal. The refrigerant container 44 has a generally cylindrical shape. Specifically, as shown in FIG. 4, the refrigerant container 44 includes a cylindrical portion 441, an upper portion 442, and a lower portion 443. The cylindrical portion 441 extends in the vertical direction. The outer diameter of the upper portion 442 is smaller than the outer diameter of the cylindrical portion 441. The upper portion 442 is connected to the upper end of the cylindrical portion 441. The upper portion 442 has a lid portion located at the upper end. The outer diameter of the lower portion 443 is smaller than the outer diameter of the cylindrical portion 441. The lower portion 443 is connected to the lower end of the cylindrical portion 441.

(2-7) Cushioning Material As shown in Fig. 3 to Fig. 5, the cushioning material 45 is attached to the refrigerant container 44. In Fig. 3 and Fig. 4, the cushioning material 45 includes a first cushioning material 451 that covers the cylindrical portion 441 and a second cushioning material 452 that covers the upper portion 442. The first cushioning material 451 is a sheet-like or cylindrical member wrapped around the cylindrical portion 441. The sheet-like member may be one sheet or multiple sheets. The cushioning material 45 is made of an elastic material such as rubber, for example.

2, 3, and 5, the protective member 46 is disposed below the refrigerant container 44. The protective member 46 is fixed to the refrigerant container 44. Here, the protective member 46 is integrated with the refrigerant container 44. In particular, the protective member 46 is integrated with the refrigerant container 44 by welding, and cannot be attached to or detached from the refrigerant container 44.

As shown in Figures 3 and 5, the protective member 46 protects the connection portion 43. The protective member 46 protects at least the connection valve 431. Here, the protective member 46 protects the connection portion 43 from the connection valve 431 to the refrigerant container 44.

In FIG. 3, the protective member 46 is spaced apart from the connection portion 43 and covers the connection portion 43. Specifically, the protective member 46 is cylindrical. The protective member 46 may surround the entire circumference of the connection portion 43, but here has an opening 461. The opening 461 is provided on the maintenance side. The maintenance side is, for example, the front plate 411 side or the side plate 414 side, and in FIG. 3 and FIG. 5, the opening 461 is located on the front plate 411 side. Also, as shown in FIG. 3, the second connecting pipe 423 connected to the connection valve 431 passes through the opening 461.

The protective member 46 is made of, for example, a metal. The protective member 46 preferably has a thickness of 2 mm or more and 10 mm or less, and more preferably 3 mm or more and 6 mm or less.

(2-9) Pedestal As shown in Fig. 2 to Fig. 5, the pedestal 47 is provided on the lower part of the refrigerant container 44 and the protective member 46. The pedestal 47 contacts the protective member 46. Here, the pedestal 47 is fixed to the protective member 46. In Fig. 3, the pedestal 47 is fixed to the protective member 46 with a bolt B.

Furthermore, the base 47 is disposed on the bottom plate 413 of the casing 41. Here, the base 47 is fixed to the bottom plate 413.

The base 47 has an elastic member 471, a support base 472, and a connecting member 473. The elastic member 471 contacts the bottom plate 413. The elastic member 471 is made of, for example, rubber. The connecting member 473 is disposed on the elastic member 471. The connecting member 473 connects the elastic member 471 and the support base 472. The support base 472 is disposed on the connecting member 473. The support base 472 is fixed to the protective member 46. The support base 472 and the connecting member 473 are made of, for example, metal.

(2-10) Control Unit The control unit 4 shown in Fig. 1 controls the components of the heat source unit 2. The control unit 4 is configured by communicatively connecting the compressor 21, the four-way switching valve 22, the pressure reducing valve 24, the gas injection valve 28, the solenoid valve 32, and the like.

The control unit 4 is realized by a computer. The control unit 4 includes a control arithmetic unit and a storage device. The control arithmetic unit can be a processor such as a CPU or a GPU. The control arithmetic unit reads a program stored in the storage device, and performs predetermined image processing and arithmetic processing according to the program. Furthermore, the control arithmetic unit can write the results of calculations to the storage device and read information stored in the storage device according to the program.

(3) User Machine The user machine 3 is installed in a building. The heat source machine 2 and the user machine 3 are thermally connected via the second heat exchanger 25. Here, the water circuit 30 of the user machine 3 is connected to a water flow path that flows inside the second heat exchanger 25.

(4) Operation The operation of the refrigeration cycle apparatus 1 will be described with reference to Fig. 1. The refrigeration cycle apparatus 1 can perform a cooling operation for cooling indoor air and a heating operation for heating indoor air for air conditioning. In the cooling operation and the heating operation, the operation of the refrigeration cycle apparatus 1 is controlled by the control unit 4.

In addition, the dashed arrows in FIG. 1 indicate the flow of refrigerant in the refrigerant circuit 20 during heating operation, and the solid arrows indicate the flow of refrigerant in the refrigerant circuit 20 during cooling operation.

(4-1) Heating Operation During heating operation, the control unit 4 switches the flow path of the four-way switching valve 22 as shown by the dotted lines in FIG. 1, and circulates the refrigerant through the compressor 21, the second heat exchanger 25, the pressure reducing valve 24, and the first heat exchanger 23 in that order.

The refrigerant compressed to high temperature and pressure by the compressor 21 flows out of the discharge port 21c as a high-temperature gas refrigerant and into the second heat exchanger 25. In the second heat exchanger 25, the high-temperature gas refrigerant heats the water in the water circuit 30, and the refrigerant liquefies. The water that has exchanged heat with the refrigerant circulates through the water circuit 30 and heats the air in the target space.

The control unit 4 monitors the temperature of the refrigerant coming out of the discharge port 21c of the compressor 21 via the temperature sensor 50, and if the temperature exceeds a predetermined value, the control unit 4 opens the gas injection valve 28.

The liquid refrigerant flowing out of the second heat exchanger 25 flows toward the economizer heat exchanger 29 and flows into the first flow path 29a of the economizer heat exchanger 29. Part of the refrigerant flowing into the first flow path 29a branches into the second flow path 29b toward the gas injection valve 28, and the rest branches into the liquid refrigerant flow path 26b of the liquid-gas heat exchanger 26. The refrigerant that flows into the second flow path 29b passes through the gas injection valve 28 and flows into the economizer heat exchanger 29 in a low-temperature gas-liquid two-phase state.

In the economizer heat exchanger 29, heat is exchanged between the gas-liquid two-phase refrigerant from the gas injection valve 28 and the high-temperature liquid refrigerant flowing through the first flow path 29a. As a result, the gas-liquid two-phase refrigerant is heated and becomes a nearly saturated gas refrigerant, and the liquid refrigerant flowing through the first flow path 29a is supercooled.

The gas refrigerant that flows out of the economizer heat exchanger 29 flows into the inlet 21b of the compressor 21. The inlet 21b of the compressor 21 is located midway through the compression stage of the compressor 21. Therefore, the gas refrigerant that flows in through the inlet 21b enters a section where the refrigerant from the suction port 21a has already been partially compressed.

The refrigerant flowing through the liquid refrigerant flow path 26b of the liquid-gas heat exchanger 26 flows toward the pressure reducing valve 24. The refrigerant that flows into the pressure reducing valve 24 expands and becomes a low-temperature gas-liquid two-phase state. This refrigerant flows into the first heat exchanger 23 and evaporates in the first heat exchanger 23.

The refrigerant flowing out of the first heat exchanger 23 flows through the gas refrigerant flow path 26a of the liquid-gas heat exchanger 26 toward the accumulator 27. The refrigerant that flows into the accumulator 27 has excess liquid components recovered in the accumulator 27.

In the liquid-gas heat exchanger 26, heat is exchanged between the liquid refrigerant heading to the pressure reducing valve 24 and the gas refrigerant flowing out of the first heat exchanger 23, so that the refrigerant heading to the pressure reducing valve 24 is subcooled.

The gas refrigerant that flows out of the accumulator 27 returns to the intake port 21a of the compressor 21. The gas refrigerant is then compressed to a high temperature and high pressure by the compressor 21.

(4-2) Cooling Operation During cooling operation, the control unit 4 switches the flow path of the four-way switching valve 22 as shown by the solid lines in FIG. 1, and circulates the refrigerant through the compressor 21, the first heat exchanger 23, the pressure reducing valve 24, and the second heat exchanger 25 in that order.

The refrigerant compressed to high temperature and pressure by the compressor 21 becomes a high-temperature gas refrigerant, flows out of the discharge port 21c, and flows into the first heat exchanger 23. In the first heat exchanger 23, the high-temperature gas refrigerant exchanges heat with the outside air, and the refrigerant is liquefied.

The liquid refrigerant flowing out of the first heat exchanger 23 expands in the pressure reducing valve 24 and becomes a low-temperature gas-liquid two-phase state. This refrigerant flows into the second heat exchanger 25 via the refrigerant flow path 31. During cooling operation, the solenoid valve 32 is closed, so the refrigerant flowing through the refrigerant flow path 31 does not flow into the economizer heat exchanger 29.

The refrigerant that flows into the second heat exchanger 25 exchanges heat with the water flowing through the water circuit 30 in the second heat exchanger 25, evaporating and cooling the water. The water that has exchanged heat with the refrigerant circulates through the water circuit 30 to cool the air in the target space.

The gas refrigerant flowing out of the second heat exchanger 25 travels through the gas refrigerant flow path 26a of the liquid-gas heat exchanger 26 toward the accumulator 27. The refrigerant that flows into the accumulator 27 has excess liquid components recovered in the accumulator 27.

The gas refrigerant that flows out of the accumulator 27 returns to the intake port 21a of the compressor 21. The gas refrigerant is then compressed to a high temperature and high pressure by the compressor 21.

(5) Refrigerant Charging Method A method for charging a flammable refrigerant into the refrigerant circuit 20 of the heat source unit 2 will be described with reference to FIGS.

First, a heat source unit 2 is prepared, which includes a refrigerant circuit 20, a connecting pipe 42 connected to the refrigerant circuit 20, a connection part 43 connected to the connecting pipe 42, a refrigerant container 44 connected to the connection part 43, a cushioning material 45 attached to the refrigerant container 44, a protective member 46 that protects the connection part 43, and a base 47 fixed to the protective member 46. A small amount of flammable refrigerant is sealed in the refrigerant circuit 20. The refrigerant container 44 is filled with flammable refrigerant. Such a heat source unit 2 is transported to the installation location (on-site).

The heat source unit 2 is installed on-site. Then, the connection valve 431 is opened to allow the refrigerant filled in the refrigerant container 44 to flow through the connection part 43 and the communication pipe 42 into the refrigerant circuit 20. This allows the flammable refrigerant filled in the refrigerant container 44 to be supplied to the refrigerant circuit 20. In this manner, in this embodiment, the flammable refrigerant is sealed in the refrigerant circuit 20 when the heat source unit 2 is installed.

(6) Features (6-1)
The heat source unit 2 according to this embodiment includes a refrigerant circuit 20, a refrigerant container 44, a connection portion 43, a communication pipe 42, and a casing 41. The refrigerant circuit 20 includes a compressor 21 and a first heat exchanger 23. The refrigerant container 44 is connected to the refrigerant circuit 20. The refrigerant container 44 is filled with a flammable refrigerant. The connection portion 43 is connected to the refrigerant container 44. The communication pipe 42 connects the connection portion 43 and the refrigerant circuit 20. The casing 41 accommodates the compressor 21, the first heat exchanger 23, the refrigerant container 44, the connection portion 43, and the communication pipe 42. The refrigerant container 44 is supported by a bottom plate 413 of the casing 41.

According to the heat source unit 2 of this embodiment, the refrigerant container 44 filled with a flammable refrigerant is fixed to the bottom plate 413 of the casing 41. Therefore, the refrigerant container 44 can be positioned more stably than when it is fixed to a support column in a cantilever manner. Therefore, safety can be improved even if the refrigerant container 44 is filled with a flammable refrigerant.

(6-2)
In the heat source unit 2 of the present embodiment, the connection portion 43 is preferably provided at the bottom of the refrigerant container 44 .

Here, the connection part 43 is provided at the bottom of the refrigerant container 44, and is fixed to the bottom plate 413 of the casing 41 in such a manner that the flammable refrigerant flows from the bottom of the refrigerant container 44 into the refrigerant circuit 20. Therefore, even if refrigerant oil flows into the refrigerant container 44 during normal operation such as cooling operation or heating operation after refrigerant is supplied from the refrigerant container 44 to the refrigerant circuit 20, the refrigerant oil is easily discharged because the refrigerant container 44 is placed upside down. This improves the dischargeability of the refrigerant oil contained in the refrigerant.

In addition, since the refrigerant container 44 is placed upside down, the length of the connecting pipe 42 can be shortened.

(6-3)
The heat source unit 2 of the present embodiment preferably further includes a protective member 46. The protective member 46 is disposed below the refrigerant container 44. The protective member 46 also protects the connection portion 43.

Here, the protective member 46 protects the connection part 43 that is connected to the refrigerant container 44 filled with a flammable refrigerant. This makes it possible to prevent the connection part 43 from being damaged when installing the heat source unit 2, etc.

(6-4)
In the heat source unit 2 of the present embodiment, the connection portion 43 preferably has a connection valve 431 that opens and closes the communication pipe 42. The protection member 46 protects the connection valve 431. The protection member 46 has an opening 461.

Here, the protective member 46 can protect the connection valve 431 that opens and closes the connecting pipe 42 connected to the refrigerant circuit 20, thereby further improving safety. In addition, work can be performed through the opening 461 of the protective member 46, improving workability.

(6-5)
In the heat source unit 2 of the present embodiment, the opening 461 is preferably provided on the maintenance side.

In this case, the opening 461 of the protective member 46 is provided on the maintenance side, so that an operator can easily perform maintenance of the connection parts 43, such as the connection valve 431, through the opening 461 by removing the maintenance side plate (e.g., the front plate 411) of the casing 41.

(6-6)
The heat source unit 2 of the present embodiment preferably further includes a base 47. The base 47 is disposed on the bottom plate 413 of the casing 41. The base 47 contacts the protective member 46.

In this manner, the refrigerant container 44 may be fixed to the bottom plate 413 of the casing 41 via the base 47 and the protective member 46.

(6-7)
In the heat source unit 2 of the present embodiment, the base 47 is preferably fixed to the protective member 46 .

In this case, the base 47 arranged on the bottom plate 413 of the casing 41 and the protective member 46 are fixed, so that the connection portion 43 can be more appropriately protected by the protective member 46.

(6-8)
In the heat source unit 2 of the present embodiment, the base 47 preferably has an elastic member 471. The elastic member 471 contacts the bottom plate 413.

Here, even if the refrigerant container 44 is dropped, the elastic member 471 absorbs the impact of the drop, thereby preventing damage to the refrigerant container 44.

(6-9)
In the heat source unit 2 of the present embodiment, the connection pipe 42 preferably has a capillary 421 .

Here, even if a load is applied to the connecting pipe 42 from the refrigerant circuit 20 side, the capillary 421 acts as an elastic member, thereby reducing the load applied to the connection part 43 (particularly the connection valve 431).

(6-10)
The heat source unit 2 of the present embodiment preferably further includes a buffer material 45. The buffer material 45 is attached to the refrigerant container 44.

Here, even if the refrigerant container 44 is subjected to an impact such as being dropped, the cushioning material 45 can absorb the impact and protect the refrigerant container 44.

(6-11)
In the heat source unit 2 of the present embodiment, the communication pipe 42 is preferably connected to the low pressure side of the refrigerant circuit 20 .

In this way, the refrigerant container 44 may be connected to the low pressure side of the refrigerant circuit 20 via the connecting pipe 42 and the connection part 43.

(6-12)
The refrigeration cycle device 1 of the present embodiment includes a heat source unit 2 and a utilization unit 3. The heat source unit 2 is any one of the heat source units 2 described above. The utilization unit 3 is connected to the heat source unit 2.

The refrigeration cycle device 1 of this embodiment allows the flammable refrigerant to be filled into the refrigerant circuit 20 from a stably positioned refrigerant container 44, improving safety.

(7) Modifications (7-1) Modification 1
In the above embodiment, in the second heat exchanger 25, the refrigerant flowing through the refrigerant circuit 20 exchanges heat with the water flowing through the water circuit 30, but this is not limited to the above. In this modification, the refrigerant flowing through the refrigerant circuit 20 may exchange heat with the air in the target space. In this case, the water circuit 30 is omitted, and the second heat exchanger 25 is disposed in the target space.

(7-2) Modification 2
In the above embodiment, the casing 41 accommodates the entire refrigerant circuit 20. However, this is not limited to this. In the present modified example, the casing 41 accommodates only a portion of the refrigerant circuit 20.

　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: refrigeration cycle device 2: heat source device 3: user device 20: refrigerant circuit 21: compressor 23: first heat exchanger (heat exchanger)
41: Casing 413: Bottom plate 42: Communication pipe 43: Connection portion 431: Connection valve 44: Coolant container 45: Cushioning material 46: Protective member 461: Opening 47: Base 471: Elastic member

JP 2000-28237 A

Claims (12)

A refrigerant circuit (20) including a compressor (21) and a heat exchanger (23);
a refrigerant container (44) connected to the refrigerant circuit and filled with a flammable refrigerant;
A connection part (43) connected to the refrigerant container;
a communication pipe (42) connecting the connection portion and the refrigerant circuit;
a casing (41) that accommodates the compressor, the heat exchanger, the refrigerant container, the connection portion, and the connecting pipe;
Equipped with
The refrigerant container is supported on a bottom plate (413) of the casing. The connection portion is provided at a lower portion of the refrigerant container.
The heat source machine according to claim 1. The cooling system further includes a protective member (46) disposed below the refrigerant container and protecting the connection portion.
The heat source machine according to claim 2. The connection portion has a connection valve (431) that opens and closes the communication pipe,
The protective member protects the connection valve,
The protective member has an opening (461).
The heat source machine according to claim 3. The opening is provided on the maintenance side.
The heat source machine according to claim 4. The housing further includes a base (47) disposed on a bottom plate of the casing;
The base is in contact with the protective member.
The heat source machine according to any one of claims 3 to 5. The base is fixed to the protective member.
The heat source machine according to claim 6. The base has an elastic member (471) that contacts the bottom plate.
The heat source machine according to claim 6 or 7. The connecting tube has a capillary (421).
The heat source machine according to any one of claims 1 to 8. Further comprising a cushioning material (45) attached to the refrigerant container.
The heat source machine according to any one of claims 1 to 9. The communication pipe is connected to the low pressure side of the refrigerant circuit.
The heat source machine according to any one of claims 1 to 10. A heat source machine according to any one of claims 1 to 11,
A utilization machine (3) connected to the heat source machine;
A refrigeration cycle device (1).

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