JP2018162924A - Air conditioner - Google Patents

Abstract

To provide an air conditioner capable of suppressing an excessive increase in high pressure at the start of heating operation, regardless of the capacity of an indoor unit connected. In an indoor functional force determination operation, the compressor 21 is driven at a speed Rj at the time of capacity determination, and the low pressure PLs when the indoor units 5a to 5c are cooled one by one is taken in from the low pressure sensor 32 and taken in. An indoor unit whose low-pressure PLs is less than the threshold pressure Pth is determined as a small capacity A, and an indoor unit whose captured low-pressure PLs is equal to or higher than the threshold pressure Pth is determined as a large capacity B. When the indoor unit that performs the heating operation is only the one determined to have the small capacity A, the small capacity start pattern Rpa is adopted as the start speed pattern Rp. On the other hand, when at least one of the indoor units that perform the heating operation is determined to have the high capacity B, the high capacity start pattern Rpb is adopted as the start speed pattern Rp. [Selection] Figure 2

Description

  The present invention relates to an air conditioner in which an outdoor unit and an indoor unit are connected by a refrigerant pipe.

  Conventionally, as an air conditioner, for example, a plurality of indoor units are connected to one outdoor unit by liquid pipes and gas pipes, and a cooling operation or a heating operation can be performed simultaneously by a plurality of indoor units. It has been known. In such an air conditioner, the compressor speed at the start of the air-conditioning operation (hereinafter referred to as start-up speed) is determined in advance.

  In the air conditioner as described above, when the outside air temperature is high when starting the heating operation, the evaporation capacity in the outdoor heat exchanger functioning as an evaporator becomes excessive, and the low pressure rises. May rise and exceed the compensation upper limit of the compressor. And when high pressure exceeds a compensation upper limit, since a compressor stops protection, there exists a problem that heating operation is interrupted.

  In order to solve the above problems, in the air conditioner described in Patent Document 1, when the outside air temperature detected at the start of the heating operation is higher than a predetermined reference outside air temperature, the rotation speed at startup of the compressor Is low. Thereby, since it can suppress that evaporation capability becomes excess in an outdoor heat exchanger, it can prevent that a high voltage | pressure rises excessively.

JP-A-8-219530

  By the way, in the air conditioner, the capacity of the indoor unit connected to the outdoor unit (mainly determined by the size of the indoor heat exchanger provided in each indoor unit) varies, and one indoor unit having a certain capacity May be connected, or multiple indoor units with different capacities may be connected. In such an air conditioner, when only one indoor unit with a small capacity is connected to the outdoor unit or when an indoor unit with various capacities is connected, only an indoor unit with a small capacity is available at the start of operation. When operating, the difference between the capacity of the outdoor unit (mainly determined by the size of the outdoor heat exchanger provided in the outdoor unit) and the capacity on the indoor unit side becomes large.

  Condensing capacity in an indoor heat exchanger that functions as a condenser when heating operation is started with an air conditioner that has a small capacity on the indoor unit side and a large difference between the capacity of the outdoor unit and the capacity on the indoor unit side as described above Compared to the above, the evaporation capacity in the outdoor heat exchanger becomes excessive. When the evaporation capacity in the outdoor heat exchanger is excessive compared to the condensation capacity in the indoor heat exchanger, the indoor unit can be operated by operating one indoor unit having a large capacity or by operating a plurality of indoor units. Compared with the case where the difference between the capacity of the outdoor unit and the capacity of the indoor unit becomes small, such as when the capacity on the unit side becomes large, the low pressure increases and accordingly the high pressure also increases.

  Therefore, when the capacity on the indoor unit side is small and the difference between the capacity of the outdoor unit and the capacity on the indoor unit side is large, the rotation speed at startup is the same as when the difference between the capacity of the outdoor unit and the capacity on the indoor unit side is small. If the compressor was started up, the high pressure would rise excessively and the compensation upper limit of the compressor could be exceeded.

  In addition, even when applying the technique described in Patent Document 1 when starting the heating operation with an air conditioner in which the capacity of the indoor unit is small and the difference between the capacity of the outdoor unit and the capacity of the indoor unit is large, If the rotation speed at startup of the compressor is not lowered as in the case where the detected outside air temperature is not higher than a predetermined reference outside air temperature, an excessive increase in high pressure cannot be prevented. Even if the detected outside air temperature is higher than a predetermined reference outside air temperature and the compressor rotation speed is lowered, the capacity on the indoor unit side is small, and the difference between the capacity of the outdoor unit and the capacity on the indoor unit side is small. When becomes large, there is a fear that high pressure overheating cannot be sufficiently suppressed.

  The present invention solves the above-described problems, and an object thereof is to provide an air conditioner that can suppress an excessive increase in high pressure at the start of heating operation even when indoor units of any capacity are connected. And

  In order to solve the above-described problems, an air conditioner according to the present invention includes a compressor, an outdoor unit having low pressure detection means for detecting a low pressure that is a pressure of refrigerant sucked into the compressor, an indoor unit, and an outdoor unit. A liquid pipe and a gas pipe for connecting the air conditioner and the indoor unit, and a control means for driving and controlling the compressor, the control means performing the cooling operation and using the low pressure detected by the low pressure detecting means. When performing the indoor functional force determination operation to determine the capacity of the engine and performing the heating operation, the heating operation is performed by controlling the rotation speed at the start of the compressor based on the indoor unit capacity determined by the indoor functional force determination operation. To start.

  The air conditioner of the present invention includes an outdoor unit having a low pressure detecting means for detecting a low pressure that is a pressure of a refrigerant sucked into the compressor and the compressor, a plurality of indoor units, and the outdoor unit and the plurality of units. A refrigerant circuit connected by a plurality of liquid pipes and a plurality of gas pipes connected to the indoor unit, and a control means for driving and controlling the compressor, the control means performing a cooling operation, and a low-pressure detection means When performing the indoor functional force determination operation that determines the respective capacities of the plurality of indoor units using the low pressure detected in step S1 and performing the heating operation, each of the multiple indoor units determined by the indoor functional force determination operation is performed. Based on the capacity, the number of revolutions at the start of the compressor is controlled to start the heating operation.

  The air conditioner of the present invention configured as described above varies the number of rotations when starting the compressor at the start of the heating operation, according to the capacity of the indoor unit that performs the heating operation. Thereby, the excessive rise of the high voltage | pressure at the time of heating operation start can be suppressed.

It is explanatory drawing of the air conditioning apparatus which is embodiment of this invention, (A) is a refrigerant circuit figure, (B) is a block diagram of an outdoor unit control means. It is a rotation speed pattern determination table at the time of embodiment of this invention. It is a time chart which shows the starting pattern at the time of small ability and the starting pattern at the time of large ability which are rotation speed patterns at the time of starting. It is a flowchart which shows the process in connection with indoor functional force determination driving | operation in embodiment of this invention. It is a flowchart which shows the process in connection with control at the time of the heating operation start in embodiment of this invention.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. As an embodiment, an air conditioner will be described as an example in which three indoor units are connected to one outdoor unit in parallel through refrigerant pipes, and all the indoor units can simultaneously perform a cooling operation or a heating operation. The present invention is not limited to the following embodiments, and can be variously modified without departing from the gist of the present invention.

  As shown in FIG. 1 (A), an air conditioner 1 according to the present embodiment includes one outdoor unit 2 having three liquid side closing valves 27a to 27c and three gas side closing valves 28a to 28c. It has three indoor units 5a-5c. Although details will be described later, the capacity of the indoor units 5a to 5c is smaller than the capacity of the outdoor unit 2, the capacity of the indoor units 5b and 5c is the same, and the indoor unit 5a is more than the indoor unit 5b and the indoor unit 5c. Small ability. And the indoor units 5a-5c are connected to the outdoor unit 2 in parallel by three liquid pipes 8a, 8b, 8c and three gas pipes 9a, 9b, 9c.

  Specifically, one end of the liquid pipe 8a is connected to the liquid pipe connection part 52a of the indoor unit 5a, and the other end of the liquid pipe 8a is connected to the liquid side closing valve 27a of the outdoor unit 2. Further, one end of the liquid pipe 8b is connected to the liquid pipe connecting portion 52b of the indoor unit 5b, and the other end of the liquid pipe 8b is connected to the liquid side closing valve 27b of the outdoor unit 2. One end of the liquid pipe 8 c is connected to the liquid pipe connection part 52 c of the indoor unit 5 c, and the other end of the liquid pipe 8 c is connected to the liquid side closing valve 27 c of the outdoor unit 2.

  One end of the gas pipe 9 a is connected to the gas pipe connection part 53 a of the indoor unit 5 a, and the other end of the gas pipe 9 a is connected to the gas side closing valve 28 a of the outdoor unit 2. In addition, one end of the gas pipe 9b is connected to the gas pipe connection portion 53b of the indoor unit 5b, and the other end of the gas pipe 9b is connected to the gas side shut-off valve 28b of the outdoor unit 2. One end of the gas pipe 9c is connected to the gas pipe connection portion 53c of the indoor unit 5c, and the other end of the gas pipe 9c is connected to the gas side closing valve 28c of the outdoor unit 2.

As described above, the indoor units 5a to 5c are connected to the outdoor unit 2 through the liquid pipes 8a to 8c and the gas pipes 9a to 9c, respectively, so that the refrigerant circuit 10 of the air conditioner 1 is configured.
<Configuration of outdoor unit 2>

  The outdoor unit 2 includes a compressor 21, a four-way valve 22, an outdoor heat exchanger 23, three expansion valves 24a to 24c, an accumulator 25, an outdoor fan 26, and the three liquid-side closing valves described above. 27a to 27c, three gas side closing valves 28a to 28c, and an outdoor unit control means 200. These devices other than the outdoor fan 26 and the outdoor unit control means 200 are connected to each other through refrigerant pipes described in detail below to form an outdoor unit refrigerant circuit 20 that forms part of the refrigerant circuit 10. Yes.

  The compressor 21 is a variable capacity compressor that can vary its operating capacity by being driven by a motor (not shown) whose rotational speed is controlled by an inverter. A refrigerant discharge port of the compressor 21 and a port a of the four-way valve 22 are connected by a discharge pipe 41. The refrigerant suction side of the compressor 21 and the refrigerant outflow side of the accumulator 25 are connected by a suction pipe 42.

  The four-way valve 22 is a valve for switching the direction in which the refrigerant flows, and includes four ports a, b, c, and d. As described above, the port a and the refrigerant discharge port of the compressor 21 are connected by the discharge pipe 41. The refrigerant outlet 43 is connected to the port b and one refrigerant inlet / outlet of the outdoor heat exchanger 23. The port c and the refrigerant inflow side of the accumulator 25 are connected by a refrigerant pipe 46. One end of the outdoor unit gas pipe 45 is connected to the port d.

  One end of each of the three outdoor unit gas distribution pipes 45 a to 45 c is connected to the other end of the outdoor unit gas pipe 45. The other end of the outdoor unit gas distribution pipe 45a is connected to the gas side closing valve 28a. The other end of the outdoor unit gas distribution pipe 45b is connected to the gas side closing valve 28b. The other end of the outdoor unit gas distribution pipe 45c is connected to the gas side closing valve 28c.

  The outdoor heat exchanger 23 exchanges heat between the outside air taken into the outdoor unit 2 from the suction port (not shown) and the refrigerant by the rotation of the outdoor fan 26. As described above, one refrigerant inlet / outlet of the outdoor heat exchanger 23 and the port b of the four-way valve 22 are connected by the refrigerant pipe 43. One end of the outdoor unit liquid pipe 44 is connected to the other refrigerant inlet / outlet of the outdoor heat exchanger 23. The outdoor heat exchanger 23 functions as a condenser when the refrigerant circuit 10 is in a cooling cycle, and functions as an evaporator when the refrigerant circuit 10 is in a heating cycle.

  One end of each of the three outdoor unit liquid distribution tubes 44 a to 44 c is connected to the other end of the outdoor unit liquid tube 44. The other end of the outdoor unit liquid distribution pipe 44a is connected to the liquid side closing valve 27a. The other end of the outdoor unit liquid distribution pipe 44b is connected to the liquid side closing valve 27b. The other end of the outdoor unit liquid distribution pipe 44c is connected to the liquid side closing valve 27c.

  The three expansion valves 24a to 24c are electronic expansion valves driven by a pulse motor (not shown), and the opening degree is adjusted by the number of pulses applied to the pulse motor. The expansion valve 24a is provided in the outdoor unit liquid distribution pipe 44a. The expansion valve 24b is provided in the outdoor unit liquid distribution pipe 44b. The expansion valve 24c is provided in the outdoor unit liquid distribution pipe 44c. By adjusting the opening degree of each of the expansion valves 24a to 24c, the amount of refrigerant flowing through the indoor units 5a to 5c is adjusted.

  As described above, in the accumulator 25, the refrigerant inflow side and the port c of the four-way valve 22 are connected by the refrigerant pipe 46, and the refrigerant outflow side and the refrigerant suction port of the compressor 21 are connected by the suction pipe 42. The accumulator 25 separates the inflowing refrigerant into a gas refrigerant and a liquid refrigerant, and causes the compressor 21 to suck only the gas refrigerant through the suction pipe 42.

  The outdoor fan 26 is a propeller fan formed of a resin material disposed in the vicinity of the outdoor heat exchanger 23, and the outdoor fan 26 is rotated by a fan motor (not shown) so that the outdoor fan 2 is not shown. Outside air is taken into the interior of the outdoor unit 2 from the suction port, and the outside air heat-exchanged with the refrigerant flowing in the outdoor heat exchanger 23 is discharged to the outside of the outdoor unit 2 from a blower outlet (not shown) provided in the outdoor unit 2.

  In addition to the configuration described above, the outdoor unit 2 is provided with various sensors. As shown in FIG. 1A, a discharge pipe 41 includes a high-pressure sensor 31 that is a high-pressure detection unit that detects the pressure of refrigerant discharged from the compressor 21 (hereinafter referred to as high pressure), and a compressor 21. A discharge temperature sensor 33 that detects the temperature of the discharged refrigerant is provided.

  Near the refrigerant inflow side of the accumulator 25 in the refrigerant pipe 46, a low-pressure sensor 32 that is a low-pressure detection means for detecting the pressure of the refrigerant sucked into the compressor 21 (hereinafter referred to as “low pressure”), and the compressor 21 draws in the refrigerant. An intake temperature sensor 34 for detecting the temperature of the refrigerant is provided.

  A refrigerant temperature sensor 35 that detects the temperature of the refrigerant flowing into the outdoor heat exchanger 23 when the outdoor heat exchanger 23 functions as an evaporator is provided in the vicinity of the outdoor heat exchanger 23 in the outdoor unit liquid pipe 44. ing. In addition, an outdoor air temperature sensor 38 that detects the temperature of the outside air flowing into the outdoor unit 2, that is, the outside air temperature, is provided near the suction port (not shown) of the outdoor unit 2.

  Between the expansion valve 24a and the liquid side closing valve 27a in the outdoor unit liquid distribution pipe 44a, a liquid side temperature sensor 36a for detecting the temperature of the refrigerant flowing through the outdoor unit liquid distribution pipe 44a is provided. Between the expansion valve 24b and the liquid side closing valve 27b in the outdoor unit liquid distribution pipe 44b, a liquid side temperature sensor 36b for detecting the temperature of the refrigerant flowing through the outdoor unit liquid distribution pipe 44b is provided. Between the expansion valve 24c and the liquid side closing valve 27c in the outdoor unit liquid distribution pipe 44c, a liquid side temperature sensor 36c for detecting the temperature of the refrigerant flowing through the outdoor unit liquid distribution pipe 44c is provided.

  The outdoor unit gas distribution pipe 45a is provided with a gas side temperature sensor 37a that detects the temperature of the refrigerant flowing through the outdoor unit gas distribution pipe 45a. The outdoor unit gas distribution pipe 45b is provided with a gas side temperature sensor 37b that detects the temperature of the refrigerant flowing through the outdoor unit gas distribution pipe 45b. The outdoor unit gas distribution pipe 45c is provided with a gas side temperature sensor 37c that detects the temperature of the refrigerant flowing through the outdoor unit gas distribution pipe 45c.

  Further, the outdoor unit 2 is provided with an outdoor unit control means 200 which is a control means of the present invention. The outdoor unit control means 200 is mounted on a control board stored in an electrical component box (not shown) of the outdoor unit 2, and as shown in FIG. 1B, a CPU 210, a storage unit 220, a communication unit 230, The sensor input unit 240 is provided.

The storage unit 220 includes a ROM and a RAM, and includes detection values corresponding to control programs for the outdoor unit 2 and detection signals from various sensors, driving states of the compressor 21 and the outdoor fan 26, the indoor unit 5a and the indoor unit. Operation information (including operation / stop information, set temperature information, etc.) transmitted from 5b and 5c is stored. The communication unit 230 is an interface that performs communication with each indoor unit. The sensor input unit 240 captures detection results from various sensors of the outdoor unit 2 and outputs them to the CPU 210. The CPU 210 fetches detection values from various sensors periodically (for example, every 30 seconds) via the sensor input unit 240, and also indicates an operation state and operation information indicating operation start / stop transmitted from the indoor units 5a to 5c. A signal including (set temperature, room temperature, etc.) is input via the communication unit 230. The CPU 210 adjusts the opening degree of the expansion valves 24 a to 24 c and controls the drive of the compressor 21 and the outdoor fan 26 based on these various pieces of input information.
<Configuration of indoor units 5a to 5c>

  Next, the indoor units 5a to 5c will be described. The indoor units 5a to 5c include indoor heat exchangers 51a to 51c, liquid pipe connection parts 52a to 52c, gas pipe connection parts 53a to 53c, and indoor fans 54a to 54c. These constituent devices other than the indoor fans 54 a to 54 c are connected to each other through refrigerant pipes that will be described in detail below, thereby constituting indoor unit refrigerant circuits 50 a to 50 c that form part of the refrigerant circuit 10.

  Here, the capacities of the indoor units 5a to 5c are all smaller than the capacities of the outdoor units 2, the capacities of the indoor units 5b and 5c are the same, and the capacities of the indoor units 5a are higher than those of the indoor units 5b and 5c. small. Specifically, each of the indoor heat exchangers 51a to 51c is smaller than the outdoor heat exchanger 23, and the indoor heat exchanger 51a is smaller than the indoor heat exchanger 51b and the indoor heat exchanger 51c.

  Since the indoor units 5a to 5c all have the same configuration except for the above-described difference in capacity, only the configuration of the indoor unit 5a will be described in the following description, and the configuration of the indoor units 5b and 5c will be described. Omitted. In FIG. 1A, the numbers assigned to the constituent devices of the indoor unit 5a are changed from “a” to “b” or “c”, respectively, so that the configurations of the indoor units 5b and 5c corresponding to the constituent devices of the indoor unit 5a are obtained. It becomes a device.

The indoor heat exchanger 51a exchanges heat between the refrigerant and indoor air taken into the indoor unit 5a from a suction port (not shown) provided in the indoor unit 5a by rotation of the indoor fan 54a. One refrigerant inlet / outlet of the indoor heat exchanger 51a and the liquid pipe connecting portion 52a are connected by an indoor unit liquid pipe 71a. The other refrigerant inlet / outlet of the indoor heat exchanger 51a and the gas pipe connecting portion 53a are connected by an indoor unit gas pipe 72a. Each refrigerant pipe is connected to the liquid pipe connecting part 52a and the gas pipe connecting part 53a by welding, a flare nut or the like.
The indoor heat exchanger 51a functions as an evaporator when the indoor unit 5a performs a cooling operation, and functions as a condenser when the indoor unit 5a performs a heating operation.

The indoor fan 54a is a cross flow fan formed of a resin material disposed in the vicinity of the indoor heat exchanger 51a, and is rotated by a fan motor (not shown) to enter the indoor unit 5a from the suction port (not shown). Air is taken in and the indoor air heat-exchanged with the refrigerant in the indoor heat exchanger 51a is supplied to the room from an unillustrated air outlet provided in the indoor unit 5a. An indoor temperature sensor 61a for detecting the temperature of the indoor air flowing into the indoor unit 5a, that is, the indoor temperature, is provided near the suction port (not shown) of the indoor unit 5a.
<Operation of Refrigerant Circuit 10>

Next, the flow of the refrigerant and the operation of each part in the refrigerant circuit 10 when the air-conditioning apparatus 1 of the present embodiment performs the air conditioning operation will be described with reference to FIG. In the following description, first, the case where the indoor units 5a to 5c perform the heating operation will be described, and then the case where the indoor units 5a to 5c perform the cooling operation will be described. In FIG. 1A, the solid line arrows indicate the refrigerant flow during the heating operation in the refrigerant circuit 10, and the broken line arrows indicate the refrigerant flow during the cooling operation in the refrigerant circuit 10.
<Heating operation>

  When the air conditioner 1 performs the heating operation, the four-way valve 22 is in the state indicated by the solid line in FIG. 1A, that is, the port a and the port d of the four-way valve 22 communicate with each other, and the port b and the port c. Is switched to communicate. Thereby, the refrigerant circuit 10 enters a state in which the refrigerant flows in the direction indicated by the solid line arrow in FIG. 1A, the outdoor heat exchanger 23 functions as an evaporator, and the indoor heat exchangers 51a to 51c each function as a condenser. It becomes a functioning heating cycle.

  When the compressor 21 is started in the state of the refrigerant circuit 10 as described above, the high-pressure refrigerant discharged from the compressor 21 flows into the four-way valve 22 from the discharge pipe 41 and flows through the outdoor unit gas pipe 45 from the four-way valve 22. To the outdoor unit gas distribution pipes 45a to 45c. The refrigerant branched into the outdoor unit gas distribution pipes 45a to 45c flows into the gas pipes 9a to 9c via the gas side closing valves 28a to 28c.

  The refrigerant flowing through the gas pipe 9a flows into the indoor unit 5a through the gas pipe connection part 53a of the indoor unit 5a. The refrigerant flowing into the indoor unit 5a flows through the indoor unit gas pipe 72a, flows into the indoor heat exchanger 51a, and condenses by exchanging heat with the indoor air taken into the indoor unit 5a by the rotation of the indoor fan 54a. To do. Moreover, the refrigerant | coolant which flows through the gas pipe 9b flows in into the indoor unit 5b via the gas pipe connection part 53b of the indoor unit 5b. The refrigerant flowing into the indoor unit 5b flows through the indoor unit gas pipe 72b and flows into the indoor heat exchanger 51b, and condenses by exchanging heat with the indoor air taken into the indoor unit 5b by the rotation of the indoor fan 54b. To do. And the refrigerant | coolant which flows through the gas pipe 9c flows in into the indoor unit 5c via the gas pipe connection part 53c of the indoor unit 5c. The refrigerant flowing into the indoor unit 5c flows through the indoor unit gas pipe 72c and flows into the indoor heat exchanger 51c, and condenses by exchanging heat with the indoor air taken into the indoor unit 5c by the rotation of the indoor fan 54c. To do.

  Thus, the indoor heat exchangers 51a to 51c each function as a condenser, and the indoor air heated by exchanging heat with the refrigerant in the indoor heat exchangers 51a to 51c is the outlet of the indoor units 5a to 5c (not shown). Are blown into the room to heat each room in which the indoor units 5a to 5c are installed.

  The refrigerant that has flowed out of the indoor heat exchanger 51a flows through the indoor unit liquid pipe 71a, and flows out to the liquid pipe 8a through the liquid pipe connecting portion 52a. The refrigerant flowing through the liquid pipe 8a flows into the outdoor unit 2 through the liquid side closing valve 27a, and flows into the outdoor unit liquid distribution pipe 44a from the liquid side closing valve 27a. In addition, the refrigerant that has flowed out of the indoor heat exchanger 51b flows through the indoor unit liquid pipe 71b, and flows out to the liquid pipe 8b through the liquid pipe connecting portion 52b. The refrigerant flowing through the liquid pipe 8b flows into the outdoor unit 2 through the liquid side closing valve 27b, and flows into the outdoor unit liquid distribution pipe 44b from the liquid side closing valve 27b. And the refrigerant | coolant which flowed out from the indoor heat exchanger 51c flows through the indoor unit liquid pipe 71c, and flows out into the liquid pipe 8c through the liquid pipe connection part 52c. The refrigerant flowing through the liquid pipe 8c flows into the outdoor unit 2 through the liquid side closing valve 27c, and flows into the outdoor unit liquid distribution pipe 44c from the liquid side closing valve 27c.

  Refrigerant flowing through each of the outdoor unit liquid distribution pipes 44 a to 44 c is decompressed by the expansion valves 24 a to 24 c and merged at the outdoor unit liquid pipe 44. The refrigerant merged in the outdoor unit liquid pipe 44 flows through the outdoor unit liquid pipe 44 and flows into the outdoor heat exchanger 23. The refrigerant flowing into the outdoor heat exchanger 23 evaporates by exchanging heat with the outside air taken into the outdoor unit 2 by the rotation of the outdoor fan 26.

The refrigerant that flows out of the outdoor heat exchanger 23 into the refrigerant pipe 43 flows in the order of the four-way valve 22, the refrigerant pipe 46, the accumulator 28, and the suction pipe 42, and is sucked into the compressor 21 and compressed again.
<Cooling operation>

  When the air conditioner 1 performs a cooling operation, the four-way valve 22 is in a state indicated by a broken line in FIG. 1A, that is, the port a and the port b of the four-way valve 22 communicate with each other, and the port c and the port d. Is switched to communicate. As a result, the refrigerant circuit 10 enters a state in which the refrigerant flows in the direction indicated by the broken line arrow in FIG. 1A, the outdoor heat exchanger 23 functions as a condenser, and the indoor heat exchangers 51a to 51c each function as an evaporator. It becomes a functioning cooling cycle.

  When the compressor 21 is started in the state of the refrigerant circuit 10 as described above, the high-pressure refrigerant discharged from the compressor 21 flows into the four-way valve 22 from the discharge pipe 41 and flows through the refrigerant pipe 43 from the four-way valve 22 to the outdoor. It flows into the heat exchanger 23. The refrigerant flowing into the outdoor heat exchanger 23 is condensed by exchanging heat with the outside air taken into the outdoor unit 2 by the rotation of the outdoor fan 26.

  The refrigerant that has flowed out of the outdoor heat exchanger 23 flows through the outdoor unit liquid pipe 44 and is divided into the outdoor unit liquid distribution pipes 44a to 44c. The refrigerant branched into the outdoor unit liquid distribution pipes 44a to 44c passes through the fully opened expansion valves 24a to 24c and flows into the liquid pipes 8a to 8c via the liquid side closing valves 27a to 27c.

  The refrigerant flowing through the liquid pipe 8a flows into the indoor unit 5a through the liquid pipe connection part 52a of the indoor unit 5a. The refrigerant flowing into the indoor unit 5a flows through the indoor unit liquid pipe 71a, flows into the indoor heat exchanger 51a, and evaporates by exchanging heat with the indoor air taken into the indoor unit 5a by the rotation of the indoor fan 54a. To do. Moreover, the refrigerant | coolant which flows through the liquid pipe 8b flows in into the indoor unit 5b via the liquid pipe connection part 52b of the indoor unit 5b. The refrigerant flowing into the indoor unit 5b flows into the indoor heat exchanger 51b through the indoor unit liquid pipe 71b, exchanges heat with the indoor air taken into the indoor unit 5b by the rotation of the indoor fan 54b, and evaporates. To do. And the refrigerant | coolant which flows through the liquid pipe 8c flows in into the indoor unit 5c via the liquid pipe connection part 52c of the indoor unit 5c. The refrigerant flowing into the indoor unit 5c flows through the indoor unit liquid pipe 71c and flows into the indoor heat exchanger 51c, evaporates by exchanging heat with the indoor air taken into the indoor unit 5c by the rotation of the indoor fan 54c. To do.

  Thus, the indoor heat exchangers 51a to 51c each function as an evaporator, and the indoor air that is cooled by exchanging heat with the refrigerant in the indoor heat exchangers 51a to 51c is the outlet of the indoor units 5a to 5c (not shown). Are blown into the room to cool each room where the indoor units 5a to 5c are installed.

  The refrigerant that has flowed out of the indoor heat exchanger 51a flows through the indoor unit gas pipe 72a, and flows out to the gas pipe 9a through the gas pipe connecting portion 53a. The refrigerant flowing through the gas pipe 9a flows into the outdoor unit 2 through the gas side closing valve 28a, and flows into the outdoor unit gas distribution pipe 45a from the gas side closing valve 28a. In addition, the refrigerant that has flowed out of the indoor heat exchanger 51b flows through the indoor unit gas pipe 72b, and flows out to the gas pipe 9b through the gas pipe connecting portion 53b. The refrigerant flowing through the gas pipe 9b flows into the outdoor unit 2 through the gas side closing valve 28b, and flows into the outdoor unit gas distribution pipe 45b from the gas side closing valve 28b. And the refrigerant | coolant which flowed out from the indoor heat exchanger 51c flows through the indoor unit gas pipe 72c, and flows out into the gas pipe 9c via the gas pipe connection part 53c. The refrigerant flowing through the gas pipe 9c flows into the outdoor unit 2 through the gas side closing valve 28c, and flows into the outdoor unit gas distribution pipe 45c from the gas side closing valve 28c.

The refrigerant flowing through each of the outdoor unit gas distribution pipes 45 a to 45 c merges in the outdoor unit gas pipe 45. The refrigerant merged in the outdoor unit gas pipe 45 flows in the order of the four-way valve 22, the refrigerant pipe 46, the accumulator 28, and the suction pipe 42, and is sucked into the compressor 21 and compressed again.
<Indoor functional force judgment operation and start-up control>

  When heating operation is started in the air conditioner 1 using the refrigerant circuit 10 as a heating cycle as described above, when the indoor unit to be operated is, for example, only the indoor unit 5a having a small capacity, the indoor heat exchanger that functions as a condenser Compared with the condensing capacity in 51a, the evaporating capacity in the outdoor heat exchanger 23 becomes excessive. And when the evaporation capability in the outdoor heat exchanger 23 becomes excessive compared with the condensation capability in the indoor heat exchanger 51a, when operating one indoor unit (indoor unit 5b or indoor unit 5c) having a large capacity, Compared with the case where the capacity on the indoor unit side is increased by operating a plurality of indoor units, the low pressure (pressure detected by the low pressure sensor 32) increases, and accordingly, the high pressure (pressure detected by the high pressure sensor 31). Also rises.

  In the above case, the same operation is performed when operating one indoor unit (indoor unit 5b or indoor unit 5c) having a large capacity or when the capacity on the indoor unit side is increased by operating a plurality of indoor units. If the compressor 21 is started at the starting rotational speed, the high pressure may rise excessively and exceed the compensation upper limit value of the compressor 21.

  Therefore, in the air conditioning apparatus 1 of the present invention, after the installation of the air conditioning apparatus 1, an indoor functional force determination operation for determining the capabilities of the indoor units 5a to 5c connected to the outdoor unit 2 is performed, Start-up for determining the rotation speed at the start-up of the compressor 21 in accordance with the ability of the indoor units 5a to 5c to be determined determined in the functional force determination operation, and controlling the rotation speed of the compressor 21 at the start of the heating operation with this rotation speed Execute hour control.

  Hereinafter, the indoor functional force determination operation and the startup control will be described in detail with reference to FIGS. 2 to 5 in addition to FIG. 1.

  In the following description, the low pressure detected by the low pressure sensor 32 is PLs (unit: MPa, described as PLsa to PLsc when it is necessary to individually refer to the indoor units 5a to 5c), and the capabilities of the indoor units 5a to 5c. The threshold pressure used for determining the pressure is Pth (unit: MPa), the rotational speed of the compressor 21 is Rs (unit: rps), and the rotation of the compressor 21 used for determining the capabilities of the indoor units 5a to 5c. Rj (unit: rps) for the capacity determination speed that is a number, A and B (A: small capacity, B: large capacity) for the capacity determination result, Rp for the rotational speed pattern at the start of the compressor 21, and small capacity Let Rpa be the small-capacity activation pattern that is the rotation speed pattern applied at the time of A, and Rpb be the large-capacity activation pattern that is the activation rotation speed pattern that is applied at the time of the large capacity B.

  Here, the speed Rj at the time of capability determination is obtained in advance through a test or the like and stored in the storage unit 220 of the outdoor unit control means 200, and the compressor is used when performing the indoor functional force determination operation. This is the rotational speed at which the compressor 21 is confirmed not to stop by the high pressure protection operation 21 or the low pressure protection operation. Further, the small-capacity start pattern Rpa and the large-capacity start pattern Rpb constituting the start-up rotation speed pattern Rp are obtained by performing a test or the like in advance and stored in the storage unit 220 of the outdoor unit control means 200. In both cases, it has been confirmed that even if the compressor 21 is started at the starting rotation speed pattern Rp, the high pressure does not rise.

  First, the startup rotation speed pattern determination table 300 shown in FIG. 2 will be described. The startup rotation speed pattern determination table 300 is stored in the storage unit 220 of the outdoor unit control means 200, and the results and operation state (run / stop) when the indoor functional force determination operation is performed are stored in the indoor unit. This is stored for each of 5a to 5c, and stores a startup rotation speed pattern Rp employed at the start of heating operation.

  Specifically, the detected rotation speed pattern determination table 300 stores, for each of the indoor units 5a to 5c, the detected low pressure PLs / determination result / startup rotation speed pattern Rp / operation state, and one adoption. A pattern is stored. Among these, the detected low pressure PLs, the determination result, and the startup rotation speed pattern Rp are items determined by executing the indoor functional force determination operation described below.

  The indoor functional force determination operation is for determining whether the respective capacities of the indoor units 5a to 5c connected to the outdoor unit 2 after the installation of the air conditioner 1 are the small capacity A or the large capacity B. Is to be done. Specifically, the refrigerant circuit 10 is set to the cooling cycle, and the compressor 21 is driven at the capacity determination rotation speed Rj stored in the storage unit 220 in advance, and the indoor units 5a to 5c are set one by one. Comparing the low-pressure PLs detected by the low-pressure sensor 32 during the cooling operation with the threshold pressure Pth stored in the storage unit 220 in advance, the capacity of the indoor units 5a to 5c is small capacity A or large capacity. It is determined whether it is B. Note that when the indoor units 5a to 5c are cooled for the indoor functional force determination operation, the air volume by the indoor fans 54a to 54c can be changed to, for example, “strong” (weak → medium → strong).

  The low pressure PLs detected when the compressor 21 is driven at the capacity determination rotation speed Rj and each of the indoor units 5a to 5c is cooled one by one is lower as the capacity of the operating indoor unit is smaller. This is because the evaporation capacity of the indoor heat exchanger functioning as an evaporator is smaller as the capacity of the indoor heat exchanger is smaller, and the indoor heat exchange of the indoor unit is compared to the condensation capacity of the outdoor heat exchanger 23 of the outdoor unit 2. This is because the lower the evaporation capacity in the vessel, the lower the pressure PLs is lowered (and the high pressure is lowered accordingly).

  Therefore, in the indoor functional force determination operation, the low pressure PLs when the compressor 21 is driven at the capacity determination rotation speed Rj and the indoor units 5a to 5c are cooled one by one as described above is taken from the low pressure sensor 32, An indoor unit in which the captured low pressure PLs is less than the threshold pressure Pth is determined as a small capacity A, and an indoor unit in which the captured low pressure PLs is greater than or equal to the threshold pressure Pth is determined to be a large capacity B.

  In FIG. 2, as an example, when the compressor 21 is driven with the capacity determination speed Rj being 45 rps, the low pressure PLsa detected when only the indoor unit 5a is cooled is 0.7 MPa, and only the indoor unit 5b is cooled. The detected low pressure PLsb is 1.1 MPa, and the low pressure PLsc detected when only the indoor unit 5c is cooled is 1.3 MPa. Then, the threshold pressure Pth is set to 0.9 MPa, the low pressure PLsa in the indoor unit 5a: 0.7 MPa <threshold pressure Pth: 0.9 MPa, so it is determined as the small capacity A, and the low pressure PLsb in the indoor unit 5b: 1.1 MPa>. Since the threshold pressure Pth is 0.9 MPa, it is determined as the large capacity B. In the indoor unit 5c, the low pressure PLsc: 1.3 MPa> the threshold pressure Pth: 0.9 MPa, so it is determined as the large capacity B.

  Although the threshold pressure Pth is 0.9 MPa here, the threshold pressure Pth is determined according to the room temperature of the room in which the indoor units 5a to 5c are installed. For example, when the room temperature is 25 ° C., the threshold pressure Pth is When Pth: 0.9 Pma, room temperature: 30 ° C., threshold pressure Pth: 1.1 Pma, and when room temperature: 20 ° C., threshold pressure Pth: 0.7 Pma are stored in the storage unit 220 in advance. . Specifically, the threshold pressure Pth is selected according to the room temperature detected by the room temperature sensors 61a to 61c. Thus, by selecting the threshold pressure Pth according to the room temperature, it is possible to accurately determine the respective capabilities of the indoor units 5a to 5c without being influenced by the difference in the surrounding environment of the indoor units 5a to 5c. .

  And according to the determination result of the capacity | capacitance of indoor unit 5a-5c, the rotation speed pattern Rp at the time of heating operation is selected. As shown in FIG. 3, the start-up rotation speed pattern Rp is a small-capacity start-up pattern Rpa when the indoor unit that is operated at the start of heating operation is the small-capacity A, and the indoor unit that is operated is the high-capacity B. In this case, the pattern is composed of two patterns, that is, a startup pattern Rpb for large capacity. As described above, the small-capacity activation pattern Rpa and the large-capacity activation pattern Rpb are stored in the storage unit 220 in advance.

  Each of these startup patterns increases the rotational speed Rs of the compressor 21 in three stages. Specifically, in the small-capacity activation pattern Rpa, first, the rotational speed Rs is driven for a fixed time tp (3 minutes as an example) with the first rotational speed Rpa1 (as an example, 28 rps) at the small capacity, and then the rotational speed Rs is set. The second rotation speed Rpa2 (for example, 42 rps) at the small capacity is increased and driven for a certain time tp, and finally the rotation speed Rs is increased to the third rotation speed Rpa3 (for example, 65 rps) for the small capacity.

  Further, in the high capacity start pattern Rpb, first, the rotational speed Rs is set to the first rotational speed Rpb1 for the large capacity (> the first rotational speed Rpa1 for the small capacity; 30 rps as an example), and then the tp is driven for a certain period of time. Is increased to the second rotation speed Rpb2 at the time of high capacity (> second rotation speed Rpa2 at the time of small capacity, as an example, 53 rps) and is driven for a predetermined time tp. Finally, the rotation speed Rs is increased to the third rotation speed Rpb3 (> small) The third rotation speed Rpa3 at the time of capacity is increased to 82 rps as an example, and the tp drive is performed for a predetermined time.

  In FIG. 2, since the indoor unit 5a is determined to have the small capacity A as an example, the small-capacity start pattern Rpa is used as the start-up rotation speed pattern Rp when only the indoor unit 5a is operated at the start of the heating operation. Yes. On the other hand, since each of the indoor unit 5b and the indoor unit 5c is determined to have a large capacity B, the startup rotation speed pattern Rp when operating only the indoor unit 5b or only the indoor unit 5c at the start of heating operation is the startup pattern at the high capacity Rpb.

  In addition, the reason why the rotational speed Rs of the compressor 21 is increased in three stages in the small capacity start pattern Rpa and the large capacity start pattern Rpb is as follows. In order to quickly raise the heating capacity after the start of the heating operation, it is desirable to increase the rotational speed of the compressor 21 at the time of activation. However, when the compressor 21 is started at a high rotational speed when the temperature of the compressor 21 is low and the refrigerant stagnation occurs due to a low outside air temperature or the like, the discharge amount of the refrigerating machine oil increases and the compressor 21 There is a risk of poor lubrication. Therefore, the compressor 21 is started at a low rotational speed immediately after the startup, and the rotational speed is increased as the temperature of the compressor 21 increases (and the refrigerant stagnation is eliminated), thereby discharging the refrigerating machine oil. It is possible to drive quickly with low volume.

  On the other hand, among the items stored in the startup rotation speed pattern determination table 300, the operation state and the adoption pattern are determined at the start of the heating operation. First, the operation state will be described. When the air conditioner 1 starts the heating operation, an operation start request is issued from at least one of the indoor units 5a to 5c that request the heating operation. As a result, the indoor unit that performs the heating operation and the indoor unit that does not perform the heating operation can be identified. Therefore, the operation state of the indoor unit that performs the heating operation is “running”, and the operation state of the indoor unit that does not perform the heating operation is “stopped”. Is done. FIG. 2 shows, as an example, the case where only the indoor unit 5a performs the heating operation. The operation state of the indoor unit 5a is “running”, and the operation state of the indoor units 5b and 5c is “stopped”, respectively. Yes.

  Next, the adoption pattern will be described. The capacity of each of the indoor units 5a to 5c in the indoor functional force determination operation executed at the time of installation, and the startup rotation speed pattern Rp when the indoor units 5a to 5c operate independently at the start of heating operation are known. It has been found which indoor unit among the indoor units 5a to 5c performs the heating operation at the start of the heating operation. Therefore, using these determination results, a startup rotation speed pattern Rp to be employed at the start of heating operation is determined.

  Specifically, when the indoor unit that performs the heating operation is only the indoor unit that has been determined to have the small capacity A, the small capacity start pattern Rpa is employed as the start speed pattern Rp. On the other hand, at least one indoor unit that performs heating operation is determined to have a large capacity B (only one indoor unit that has been determined to have a large capacity B is operated, or two or more indoors that include the large capacity B) When the machine is in operation), the high-capacity start pattern Rpb is adopted as the start-up rotation speed pattern Rp. In FIG. 2, since the heating operation is performed only by the indoor unit A determined to have the small capacity A, the small capacity start pattern Rpa is adopted as the start speed pattern Rp.

  As described above, in the air conditioner 1 of the present invention, the refrigerant circuit 10 is used as a cooling cycle in the indoor functional force determination operation performed when the air conditioner 1 is installed, and the detected air pressure is used for the indoor units 5a to 5c. The capacity is determined, and the start-up rotation speed pattern Rp is determined for each of the indoor units 5a to 5c according to the result. At the start of the heating operation, the start-up rotation speed pattern Rp according to the capacity of the indoor unit performing the heating operation is determined. Drive control of the compressor 21 is performed. For this reason, even if it is a case where the capacity | capacitance by the side of an indoor unit is small when starting a heating operation, the excessive increase of a high voltage | pressure can be suppressed.

Next, processing related to the indoor functional force determination operation executed after installation of the air conditioner 1 will be described with reference to FIG. 4, and processing related to startup control at the start of heating operation will be described with reference to FIG. . First, processing related to the indoor functional force determination operation will be described with reference to FIG. 4, and next, processing related to startup control will be described with reference to FIG. 4 and 5, ST represents a process step, and the number following this represents a step number. 4 and 5 mainly describe the processes related to the present invention, and other processes such as the pressure and temperature of the refrigerant circuit 10 mainly performed by the outdoor unit 2 (the outdoor unit control means 200) are mainly described. Description of processing related to general control of the air-conditioning apparatus 1 such as control related to is omitted.
<Indoor functional force judgment operation>

  After the air conditioner 1 is installed, the operator operates the operation unit (not shown) provided in the outdoor unit 2 or operates the remote control (not shown) of the indoor units 5a to 5c to connect to the outdoor unit 2. The indoor functional force determination operation of the indoor units 5a to 5c thus performed is instructed. The CPU 210 of the outdoor unit control means 200 that has received the instruction for the indoor functional force determination operation switches the four-way valve 21 shown in FIG. 1A to the state indicated by the broken line to set the refrigerant circuit 10 to the cooling cycle (ST1).

  Next, the CPU 210 starts up the compressor 21 at the capacity determination rotation speed Rj (ST2). Next, the CPU 210 starts the cooling operation only for the indoor unit 5a among the indoor units 5a to 5c (ST3). Specifically, the CPU 210 transmits a signal including the start of the cooling operation to the indoor unit 5a via the communication unit 230, and the indoor unit 5a that has received this signal drives the indoor fan 54a.

  Next, the CPU 210 takes in the low pressure PLsa detected by the low pressure sensor 32 via the sensor input unit 240 (ST4). The CPU 210 fetches the low pressure PLsa periodically (for example, every 30 seconds), and stores the fetched low pressure PLsa in the storage unit 220 in time series.

  Next, the CPU 210 reads out the low pressure PLsa and the threshold pressure Pth from the storage unit 220, and determines whether or not the low pressure PLsa is less than the threshold pressure Pth (ST5). Specifically, the CPU 210 determines that the low-pressure PLsa is stable, for example, if the difference between the low-pressure PLsa captured and stored most recently for one minute, that is, the low-pressure PLsa captured immediately before is within 0.1 MPa, The low pressure PLsa and the threshold pressure Pth that have been taken in and stored most recently are compared.

  If the low pressure PLsa is lower than the threshold pressure Pth in ST5 (ST5-Yes), the CPU 210 determines that the capacity of the indoor unit 5a is the small capacity A, and starts up rotation when only the indoor unit 5a starts the heating operation. The number pattern Rp is set as the small-capacity activation pattern Rpa (ST6), and the process proceeds to ST8.

  On the other hand, if the low pressure PLsa is not less than the threshold pressure Pth in ST5 (ST5-No), the CPU 210 determines that the capacity of the indoor unit 5a is the large capacity B and starts when only the indoor unit 5a starts the heating operation. The hour rotation speed pattern Rp is set to the high-capacity activation pattern Rpb (ST7), and the process proceeds to ST8.

  The CPU 210 uses the low pressure PLsa used for determining the capacity in ST5, the determination capacity determined and determined in ST6 or ST7, and the startup rotation speed pattern Rp in the room of the startup rotation speed pattern determination table 300 shown in FIG. Stores corresponding to the machine 5a.

  After ST8, the CPU 210 executes the same processing as ST3 to ST7 described above for the indoor unit 5b (processing corresponding to ST8 to ST12), and then executes the same processing as ST3 to ST7 for the indoor unit 5c. (Processing corresponding to ST13 to ST17). The processing for each of the indoor units 5b and 5c is the same as that for the indoor unit 5a, and a description thereof will be omitted. For the indoor units 5b and 5c as well, the low pressures PLsb and PLsc used for determining the capability, the determined and determined determination capability and the startup rotation speed pattern Rp are shown in the startup rotation speed pattern determination table 300 shown in FIG. The information is stored in association with the indoor unit 5b or the indoor unit 5c.

CPU210 which completed the process of ST16 or ST17 complete | finishes the process regarding an indoor functional force determination driving | operation.
<Control at startup at the start of heating operation>

  Next, processing related to start-up control during heating operation will be described with reference to FIG. If there is an air conditioning operation start instruction by the user, CPU 210 determines whether or not the user's operation instruction is a heating operation instruction (ST21). If it is not a heating operation instruction (ST21-No), the CPU 210 executes a cooling / dehumidifying operation start process that is a start process of a cooling operation or a dehumidifying operation (ST31). Here, the cooling / dehumidifying operation start processing means that the CPU 210 operates the four-way valve 22 to set the refrigerant circuit 10 to the cooling cycle, and the cooling operation or the dehumidifying operation is performed from the state where the air conditioner 1 is stopped. This process is performed when starting or when switching from the heating operation to the cooling operation or the dehumidifying operation.

  Then, the CPU 210 starts the compressor 21 and the outdoor fan 26 at a predetermined rotational speed, and performs cooling / dehumidifying operation control by fully opening the expansion valves 24a to 24c corresponding to the indoor units 5a to 5c that perform the cooling / dehumidifying operation. Start (ST32), and proceed to ST28.

  If it is a heating operation instruction in ST21 (ST21-Yes), the CPU 210 executes a heating operation start process (ST22). Here, the heating operation start process is a state in which the CPU 210 operates the four-way valve 22 and the refrigerant circuit 10 is in the state shown in FIG. 1A, that is, the refrigerant circuit 10 is set to the heating cycle. Is a process that is performed when the heating operation is started from the state where the operation is stopped, or when the cooling operation or the dehumidifying operation is switched to the heating operation.

  Next, CPU210 determines the indoor unit which performs heating operation among the indoor units 5a-5b (ST23). Of the indoor units 5a to 5c, an operation start request is issued from the indoor unit that requests the heating operation, and the CPU 210 can identify the indoor unit that performs the heating operation and the indoor unit that does not perform the operation by taking this operation start request. Then, in the startup rotation speed pattern determination table 300, the CPU 210 sets the operation state of the indoor unit that performs the heating operation to “operation” and the operation state of the indoor unit that does not perform the heating operation to “stop”.

  Next, the CPU 210 determines a startup rotation speed pattern Rp (ST24). As described above, the CPU 210 refers to the start-up rotation speed determination table 300, and when the indoor unit that performs the heating operation is only determined to have the small capacity A, the start-up rotation speed pattern Rp is set to the small capacity time. When the activation pattern Rpa is selected and at least one of the indoor units performing the heating operation is determined to have the large capacity B, the large capacity activation pattern Rpb is selected as the activation rotation speed pattern Rp. Then, the CPU 210 stores the selected startup rotation speed pattern Rp in the “adopted pattern” of the startup rotation speed pattern determination table 300.

  Next, the CPU 210 activates the compressor 21 in accordance with the activation rotational speed pattern Rp determined in ST24 and starts activation control (ST25). Specifically, if the low-capacity activation pattern Rpa is employed, the CPU 210 starts the compressor 21 at the first rotation speed Rpa1 at the small capacity and keeps the first rotation speed Rpa1 at the small capacity for a certain time. After maintaining tp, the rotation speed of the compressor 21 is increased to the second rotation speed Rpa2 for the small capacity. Then, after maintaining the second rotation speed Rpa2 at the small capacity for a certain time tp, the rotation speed of the compressor 21 is increased to the third rotation speed Rpa3 at the small capacity.

  On the other hand, if the CPU 210 adopts the high capacity start pattern Rpb, the CPU 21 starts up the compressor 21 at the first capacity Rpb1 when the capacity is high, and maintains the first speed Rpb1 when the capacity is high for a certain time tp. Thereafter, the rotational speed of the compressor 21 is increased to the second rotational speed Rpb2 when the capacity is high. Then, after maintaining the second rotation speed Rpb2 at the time of high capacity for a certain time tp, the rotation speed of the compressor 21 is increased to the third rotation speed Rpb3 at the time of high capacity.

  Next, CPU 210 determines whether or not to end the startup control (ST26). Here, when the CPU 210 adopts the low-capacity start pattern Rpa and executes the start-time control, the time during which the rotation speed Rs of the compressor 21 is set to the third rotation speed Rpa3 at the small capacity is a predetermined time tp. If so, the startup control is terminated. Further, when the CPU 210 adopts the high-capacity start pattern Rpb and executes the start-up control, the time during which the rotation speed Rs of the compressor 21 is set to the third rotation speed Rpb3 at the high capacity is a predetermined time tp. If so, the startup control is terminated.

  If the startup control is not terminated in ST26 (ST26-No), the CPU 210 returns the process to ST26 and continues the startup control. On the other hand, if the startup control is to be ended (ST26-Yes), CPU 210 executes normal control during heating operation (ST27).

  Here, the normal control refers to the capacity required from the indoor unit according to the temperature difference between the set temperature set by the indoor unit that performs the heating operation and the indoor temperature detected by the indoor unit. It is to drive the compressor 21 as the rotation speed according to the above. The CPU 210 performs the time t1 shown in FIG. 3, that is, when the time for maintaining the rotation speed of the compressor 21 at the third rotation speed Rpa3 at the small capacity by the activation pattern Rpa at the small capacity has elapsed for a certain time tp, or at the large capacity When the time during which the rotation speed of the compressor 21 is maintained at the third rotation speed Rpb3 at the time of the high capacity with the hour start pattern Rpb has elapsed for a certain time tp, the routine shifts to normal control.

  CPU210 which completed the process of ST27 or ST32 judges whether there exists the operation mode switching instruction | indication by a user (ST28). Here, the operation mode switching instruction is an instruction to switch from the current operation (here, heating operation) to another operation (cooling operation or dehumidifying operation). When there is an operation mode switching instruction (ST28-Yes), the CPU 210 returns the process to ST21. When there is no operation mode switching instruction (ST28-No), the CPU 210 determines whether or not there is an operation stop instruction by the user (ST29). Here, the operation stop instruction indicates that all the indoor units 5a to 5c stop the operation.

  If there is an operation stop instruction (ST29-Yes), the CPU 210 executes an operation stop process (ST30) and ends the process. In the operation stop process, the CPU 210 stops the compressor 21 and the outdoor fan 26 and fully closes the expansion valves 24a to 24c. Moreover, CPU210 transmits the operation stop signal to the effect of stopping an operation via the communication unit 230 to the indoor unit that has been operated among the indoor units 5a to 5c. The indoor units 5a to 5c that have received the operation stop signal stop the indoor fans 54a to 54c.

  If there is no operation stop instruction in ST29 (ST29-No), CPU 210 determines whether or not the current operation is a heating operation (ST33). If the current operation is the heating operation (ST33-Yes), the CPU 210 returns the process to ST27. If the current operation is not the heating operation (ST33-No), that is, if the current operation is the cooling operation or the dehumidifying operation, the CPU 210 returns the process to ST32.

  As described above, in the air conditioner 1 of the present invention, after the air conditioner 1 is installed, the refrigerant circuit 10 is used as the refrigeration cycle, the indoor functional force determination operation is performed by the cooling operation, and the detected low pressure PLs is used for the outdoor operation. The respective capacities of the indoor units 5a to 5c connected to the unit 2 are determined, and a startup rotation speed pattern Rp to be applied when each of the indoor units 5a to 5c is operated independently at the start of the heating operation is determined. And when starting heating operation, the compressor 21 is drive-controlled by the starting rotation speed pattern Rp corresponding to the indoor unit which performs heating operation among the indoor units 5a-5c. Thereby, even if it is a case where the capability of the indoor unit which performs heating operation is small, the excessive increase of the high voltage | pressure at the time of heating operation start can be suppressed.

  In the above-described embodiment, the air conditioner 1 in which the three indoor units 5a to 5c are connected to the outdoor unit 2 has been described as an example. However, only one indoor unit is connected to the outdoor unit. Even in such a case, the present invention can be applied. However, in this case, at the start of the heating operation, the compressor 21 is started with the startup rotation speed pattern determined by executing the indoor functional force determination operation by the cooling operation.

  Moreover, although this embodiment demonstrated the case where the fixed time tp which maintains the rotation speed of the compressor 21 in each step in each rotation speed pattern Rp shown in FIG. The time for maintaining the rotational speed of the compressor 21 at each stage may be varied depending on the operating environment. For example, when employed in the small capacity start pattern Rpa when the outside air temperature is low, the time for maintaining the first rotation speed Rpa1 for the small capacity <the time for maintaining the second rotation speed Rpa2 for the small capacity <the first for the small capacity Since the temperature of the compressor 21 rises and the refrigerant stagnation is eliminated by increasing the time for maintaining the rotational speed as the rotational speed increases, such as the time for maintaining the rotational speed at 3 rotational speeds Rpa3. The amount of refrigeration oil discharged when the machine 21 is started can be reduced as much as possible.

  Furthermore, in this embodiment, the case where the indoor functional force determination operation is executed when the air conditioner 1 is installed and the startup rotation speed pattern is determined according to the capacity of the indoor unit that performs the heating operation at the start of the heating operation is described. However, all the operation patterns of the indoor units connected to the outdoor unit 2 at the time of installation (in this embodiment, only one of the indoor units 5a to 5c is operated, and any two of the indoor units 5a to 5c are operated simultaneously. In addition, the indoor unit 5a to 5c may be operated simultaneously), and the start-up rotation speed pattern may be determined by obtaining the capacity on the indoor unit side.

DESCRIPTION OF SYMBOLS 1 Air conditioning apparatus 2 Outdoor unit 5a-5c Indoor unit 21 Compressor 23 Outdoor heat exchanger 24a-24c Expansion valve 32 Low pressure sensor 51 Indoor heat exchanger 200 Outdoor unit control part 210 CPU
220 Storage unit 240 Sensor input unit 300 Start-up rotation speed pattern determination table A Small capacity B Large capacity PLs (PLsa to PLsc) Low pressure Pth threshold pressure Rs Compressor rotation speed Rpa Small capacity start pattern Rpb High capacity start pattern Rpa1 Rpa3 Compressor rotation speed in start pattern at low capacity Rpb1 to Rpb3 Rotation speed of compressor in start pattern at high capacity Rj Rotation speed at capacity determination t time t1 Time of start-up control-normal control switching tp Rotation speed maintenance time

Claims (6)

An outdoor unit having low pressure detecting means for detecting a low pressure which is a pressure of refrigerant sucked into the compressor and the compressor, an indoor unit, a liquid pipe and a gas pipe connecting the outdoor unit and the indoor unit, An air conditioner having control means for driving and controlling a compressor,
The control means includes
The indoor functional force determination operation for performing cooling operation, performing the indoor functional force determination operation for determining the capacity of the indoor unit using the low pressure detected by the low pressure detecting means, and performing the heating operation, the indoor functional force determined by the indoor functional force determination operation Based on the capacity of the machine, start the heating operation by controlling the rotation speed at the start of the compressor,
An air conditioner characterized by that. The control means includes
Pre-stores a speed at the time of capacity determination, which is the number of rotations of the compressor when performing the indoor functional force determination operation, and a threshold pressure used when performing the indoor functional force determination operation;
In the indoor functional force determination operation, the compressor is driven at the rotation speed at the time of the capacity determination to perform the cooling operation, the low pressure detected by the low pressure detection means is captured, and the acquired low pressure is compared with the threshold pressure. Based on the capacity of the indoor unit,
The air conditioner according to claim 1. The control means includes
A startup rotation speed pattern that increases the rotation speed of the compressor stepwise according to the capacity of the indoor unit is stored in advance,
When starting the heating operation with the air conditioner, the rotational speed at the start of the compressor is controlled with the rotational speed pattern at the start corresponding to the stored capacity of the indoor unit.
The air conditioner according to claim 1 or 2, wherein An outdoor unit having low pressure detecting means for detecting a low pressure that is a pressure of refrigerant sucked into the compressor and the compressor, a plurality of indoor units, and a plurality of units that connect the outdoor units and the plurality of indoor units An air conditioner having a refrigerant circuit connected by a liquid pipe and a plurality of gas pipes, and a control means for driving and controlling the compressor,
The control means includes
When performing a cooling operation, performing an indoor functional force determination operation for determining the capabilities of each of the plurality of indoor units using the low pressure detected by the low pressure detection means, and performing a heating operation, the indoor functional force determination operation Based on the capability of each of the plurality of indoor units determined by, to start the heating operation by controlling the number of rotations at the time of starting the compressor,
An air conditioner characterized by that. The control means includes
Pre-stores a speed at the time of capacity determination, which is the number of rotations of the compressor when performing the indoor functional force determination operation, and a threshold pressure used when performing the indoor functional force determination operation;
In the indoor functional force determination operation, the compressor is driven at the speed at the time of capacity determination to cool the plurality of indoor units one by one, and each time the low pressure detected by the low pressure detection means is taken in and taken in Based on the result of comparing each of the low pressure and the threshold pressure, the capacity of the indoor unit currently operating is determined.
The air conditioning apparatus according to claim 4, wherein: The control means includes
A startup rotation speed pattern that increases the rotation speed of the compressor stepwise according to the capacity of the indoor unit is stored in advance,
When starting the heating operation with the air conditioner, the rotational speed at the start of the compressor is controlled with the rotational speed pattern at the start corresponding to the capacity of the indoor unit performing the heating operation.
The air conditioner according to claim 4 or 5, wherein

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