JP2011047620A - Air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner capable of suppressing a reduction in suction pressure of a compressor by a simple structure without changing three inter-unit piping connecting a plurality of indoor units. <P>SOLUTION: The air conditioner includes a three-piping type first outdoor unit 2 connected to a first compressor 20 and the three inter-unit piping 5 consisting of a high pressure gas pipe 7, a low pressure gas pipe 6, and a liquid pipe 8, a plurality of indoor units 4A-4D, and a second outdoor unit 3 connected by a second compressor 30 and two piping of a gas pipe 35 and a liquid pipe 36. The liquid pipe 36 is connected to the liquid pipe 8, and moreover, a third four-way valve 51 alternatively connecting the gas pipe 35 to the high pressure gas pipe 7 or the low pressure gas pipe 6 and a first four-way valve 60 allowing the communication between a refrigerant discharge pipe 25 of the first compressor 20 and the high pressure gas pipe 7, are arranged. When all of the indoor units 4A-4D perform cooling operation simultaneously, switching is performed so that the first four-way valve 60 cuts off the communication between the refrigerant discharge pipe 25 and the high pressure gas pipe 7, and the third four-way valve 51 connects the gas pipe 35 to the high pressure gas pipe 7. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention has an outdoor unit and a plurality of indoor units, and the plurality of indoor units can be simultaneously operated in a cooling operation or a heating operation, or these heating operations and a cooling operation can be performed in combination. It relates to a harmony device.

  In general, an outdoor unit and a plurality of indoor units are connected via a pipe between two units composed of a liquid pipe and a gas pipe, and the plurality of indoor units are cooled or heated. A pipe connection type (hereinafter referred to as two pipe type) air conditioner is known. Further, in recent years, an outdoor unit and a plurality of indoor units are connected via three inter-unit piping composed of a low pressure gas pipe, a high pressure gas pipe, and a liquid pipe, and the plurality of indoor units are simultaneously operated for cooling or A low-pressure gas pipe, a high-pressure gas pipe and a liquid pipe connection type (hereinafter referred to as three-pipe type) air conditioner that performs heating operation or performs a mixture of these cooling operation and heating operation has been proposed. (See Patent Document 1).

Japanese Patent No. 2804527

By the way, in this type of three-pipe type air conditioner, when a plurality of indoor units are implemented in a mixture of cooling operation and heating operation, the operation is performed using all three inter-unit pipes. On the other hand, when performing cooling operation or heating operation, two of the three inter-unit piping (liquid pipe and low-pressure gas pipe during cooling operation, liquid pipe and high-pressure gas pipe during heating operation) Is used.
Here, during cooling operation, all the low-pressure gas refrigerant evaporated in the indoor heat exchanger of the indoor unit flows through the low-pressure gas pipe and is sucked into the compressor of the outdoor unit. Loss is likely to occur. When a pressure loss occurs, the suction pressure of the compressor is reduced and the specific volume is increased, so that the capacity of the compressor is lowered, and consequently, the cooling capacity of the air conditioner is lowered. On the other hand, if the pipe diameter of the low-pressure gas pipe is greatly changed, the pressure loss is reduced, so that a reduction in the suction pressure of the compressor is suppressed, but a great cost is required.
Then, this invention solves the subject mentioned above and it aims at providing the air conditioning apparatus which can suppress the fall of the suction pressure of a compressor by simple structure, without changing piping between three units. .

  In order to achieve the above object, the present invention provides a first outdoor unit including a first compressor, a first outdoor heat exchanger, and a first outdoor expansion valve, and a plurality of indoor units including an indoor heat exchanger. And one end of the first outdoor heat exchanger is alternatively branched and connected to the refrigerant discharge pipe and the refrigerant suction pipe of the first compressor, and the inter-unit pipe is A high pressure gas pipe connected to the refrigerant discharge pipe, a low pressure gas pipe connected to the refrigerant suction pipe, and a liquid pipe connected to the other end of the first outdoor heat exchanger, One end of the heat exchanger is alternatively branched and connected to the high-pressure gas pipe and the low-pressure gas pipe, and the other end of the indoor heat exchanger is connected to the liquid pipe via the liquid branch pipe. The indoor unit can be cooled or heated at the same time, or these cooling operations and In the air conditioner configured to be able to perform the cell operation in a mixed manner, two pipes of a gas pipe and a liquid pipe having a second compressor, a second outdoor heat exchanger, and a second outdoor expansion valve A second outdoor unit to be connected to the liquid pipe of the second outdoor unit and a liquid pipe of the inter-unit pipe, and a gas pipe of the second outdoor unit to a high-pressure gas pipe or a low-pressure gas of the inter-unit pipe A valve body kit having a flow path switching valve that is selectively connected to a pipe, and the first outdoor unit includes a valve body that allows the refrigerant discharge pipe and the high-pressure gas pipe to communicate with each other. When the units are cooled simultaneously, the valve element cuts off the communication between the refrigerant discharge pipe and the high pressure gas pipe, and the flow path switching valve is switched so as to connect the gas pipe to the high pressure gas pipe. It is characterized by being

  In this configuration, the valve body is a single first four-way valve having four ports, the refrigerant discharge pipe is connected to the first port of the first four-way valve, and the high-pressure gas pipe is connected to the second port. And the third port is closed, or the third port is connected to the low-pressure gas pipe via a capillary tube, and the fourth port is closed, or the fourth port is connected to the capillary tube. It is good also as a structure which connected the said low pressure gas pipe | tube via.

  The first outdoor unit includes a second four-way valve between the first compressor and the first outdoor heat exchanger, and the refrigerant discharge branch branched from between the second four-way valve and the first compressor. The high pressure gas pipe is connected to a pipe via the valve body, the low pressure gas pipe is connected to a refrigerant suction branch pipe branched from between the second four-way valve and the first compressor, and the second four-way valve May be configured to communicate the low-pressure gas pipe and the first outdoor heat exchanger at the first switching position, and to communicate the first compressor and the first outdoor heat exchanger at the second switching position. .

  The valve body kit includes a single third four-way valve as the flow path switching valve, the gas pipe is connected to a first port of the third four-way valve, and the low-pressure gas pipe is connected to a second port. The high pressure gas pipe may be connected to the third port and the fourth port may be closed, or the low pressure gas pipe may be connected to the fourth port via a capillary tube.

  Moreover, the said valve body kit is good also as a structure provided in the outer side of the housing of the said 2nd outdoor unit.

  The first compressor may be configured to have at least half the capacity of all compressors included in the air conditioner.

  According to the present invention, when the indoor unit is in a cooling operation, the valve body included in the first outdoor unit blocks communication between the refrigerant discharge pipe of the compressor and the high-pressure gas pipe, and the gas pipe of the second outdoor unit Since the flow path switching valve that alternatively connects the low-pressure gas pipe or the high-pressure gas pipe is switched to connect the gas pipe to the high-pressure gas pipe, the first outdoor unit passes the low-pressure gas pipe through the second outdoor In the unit, the refrigerant is returned to each outdoor unit through the high-pressure gas pipe. For this reason, since the pipe diameter of these low-pressure gas pipes and high-pressure gas pipes can be increased with respect to the amount of refrigerant flowing through each gas pipe, pressure loss in the low-pressure gas pipe and high-pressure gas pipe can be suppressed. A reduction in the suction pressure of the compressor of the outdoor unit can be prevented, and thus a reduction in cooling capacity can be prevented.

It is a circuit diagram which shows one Embodiment of the air conditioning apparatus which concerns on this invention, and shows the flow of the refrigerant | coolant at the time of this air conditioning apparatus being air-cooled. It is a circuit diagram which shows the flow of the refrigerant | coolant at the time of an air conditioning apparatus carrying out heating operation. It is a circuit diagram which shows the flow of the refrigerant | coolant at the time of air-conditioning apparatus carrying out cooling-heating mixed operation by cooling main. It is a circuit diagram which shows the flow of the refrigerant | coolant at the time of an air conditioning apparatus carrying out cooling-heating mixed operation mainly by heating.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a circuit diagram showing an embodiment of an air conditioner according to the present invention. The air conditioner 1 includes a first outdoor unit 2 that is a three-pipe outdoor unit, a second outdoor unit 3 that is a two-pipe outdoor unit, and a plurality of (for example, four) indoor units 4A. 4B, 4C, 4D. The inter-unit pipe 5 that connects the first outdoor unit 2 and the second outdoor unit 3 to the indoor units 4A to 4D is composed of a low-pressure gas pipe 6, a high-pressure gas pipe 7, and a liquid pipe 8. The harmony device 1 enables the indoor units 4 </ b> A to 4 </ b> D to be cooled or heated at the same time, or can be implemented by mixing these cooling and heating operations.

  The indoor unit 4A includes an indoor heat exchanger 10A and an indoor expansion valve 11A. One end of the indoor heat exchanger 10A is connected to the liquid pipe 8 via a liquid branch pipe 18A provided with the indoor expansion valve 11A. Connected. A branch pipe 12A is connected to the other end of the indoor heat exchanger 10A, and this branch pipe 12A branches into a high-pressure gas branch pipe 13A and a low-pressure gas branch pipe 14A. The high-pressure gas branch pipe 13A is connected to the high-pressure gas pipe 7 via the first on-off valve 15A, and the low-pressure gas branch pipe 14A is connected to the low-pressure gas pipe 6 via the second on-off valve 16A.

  The indoor unit 4A includes a temperature sensor (not shown) for detecting the inlet / outlet temperature and room temperature of the indoor heat exchanger 10A, a pressure sensor (not shown) for detecting the refrigerant pressure in the indoor heat exchanger 10A, and the like. In addition, an indoor control device (not shown) for inputting the detection results of these sensors and controlling the indoor unit 4A is provided. Since the indoor units 4B to 4D have substantially the same configuration as the indoor unit 4A, the same portions are denoted by the same reference numerals, and description thereof is omitted.

The first outdoor unit 2 includes a variable capacity type first compressor (DC inverter compressor) 20, a first four-way valve (valve element) 60 connected in parallel to the discharge side of the first compressor 20, and a first Two four-way valves 24, a plurality of (two in this embodiment) first outdoor heat exchangers 21 and 21 connected to the second four-way valve 24, and a first expansion valve (first outdoor expansion valve) 22. , 22 and a first unit case (housing) 23 for housing them.
The first unit case 23 includes a low pressure gas pipe service valve 23A to which each device in the first unit case 23 and the low pressure gas pipe 6, the high pressure gas pipe 7 and the liquid pipe 8 of the inter-unit pipe 5 are connected, respectively. A high-pressure gas pipe service valve 23B and a first liquid pipe service valve 23C are provided.
In this configuration, the capacity of the first compressor 20 is configured to have at least half the capacity of all the compressors included in the air conditioner 1. According to this, for example, when the cooling and heating mixed operation is executed with a load balance of 50%: 50% between the cooling load and the heating load, only the first outdoor unit 2 including the first compressor 20 is used. Thus, each of the indoor units 4A to 4D can be cooled and heated. In addition, when the cooling load or the heating load is increased and, for example, the load balance is changed to 60%: 40% between the cooling load and the heating load, the second outdoor unit 3 takes charge of the excess cooling load. Can do. For this reason, the air conditioning operation with the load balance can be realized no matter how the load balance of the cooling load and the heating load of the indoor units 4A to 4D during the cooling / heating mixed operation changes.
The second four-way valve 24 includes four ports, and the refrigerant discharge pipe 25 of the first compressor 20 is connected to the first port α. One end of a refrigerant discharge branch pipe 25A that branches between the first compressor 20 and the second four-way valve 24 is connected to the refrigerant discharge pipe 25, and the other end of the refrigerant discharge branch pipe 25A is the first four-way valve. 60. Reference numeral 45 denotes a check valve.

In addition, an in-unit gas pipe 26 is connected to the second port β of the second four-way valve 24. The in-unit gas pipe 26 is branched into two in-unit branch gas pipes 26A and 26A, and each of the first outdoor heat exchanges. It is connected to one end side of the vessels 21, 21. In this configuration, an in-unit branch gas pipe 26A connected to one first outdoor heat exchanger 21 is provided with an electromagnetic open / close valve (open / close valve) 27, and a refrigerant is selected for the first outdoor heat exchangers 21 and 21. It is possible to distribute it.
In-unit branch liquid pipes 29A and 29A are connected to the other ends of the first outdoor heat exchangers 21 and 21, respectively. These in-unit branch liquid pipes 29A and 29A merge to form a first unit internal liquid pipe (liquid pipe). ) 29 and is connected to the liquid pipe 8 of the inter-unit pipe 5 via the first liquid pipe service valve 23C. Moreover, the above-described first expansion valves 22 and 22 are provided in the in-unit branch liquid pipes 29A and 29A, respectively.

The refrigerant suction pipe 28 of the first compressor 20 is connected to the third port γ of the second four-way valve 24. One end of a refrigerant suction branch pipe 28A that branches between the first compressor 20 and the second four-way valve 24 is connected to the refrigerant suction pipe 28, and the other end of the refrigerant suction branch pipe 28A is a low-pressure gas pipe service valve. It is connected to the low pressure gas pipe 6 through 23A.
A capillary tube 46 is connected to the fourth port δ of the second four-way valve 24, and the other end of the capillary tube 46 is connected to the refrigerant suction pipe 28. Here, when the 1st outdoor unit 2 stops, the flow of the refrigerant | coolant in the refrigerant | coolant piping (refrigerant suction pipe 28 and unit internal gas pipe | tube 26) in this 1st outdoor unit 2 may stop. For this reason, in order to prevent the accumulation of the refrigerant in the refrigerant pipes, the refrigerant suction pipe 28 is connected to the fourth port δ via the capillary tube 46. The fourth port δ may be simply closed with a sealing plug or the like without connecting the refrigerant suction pipe 28 to the fourth port δ via the capillary tube 46.

Similarly to the second four-way valve 24, the first four-way valve 60 has four ports, and the other end of the refrigerant discharge branch pipe 25A is connected to the first port P. One end of the high pressure gas pipe 61 in the unit is connected to the second port Q of the first four-way valve 60, and the other end of the high pressure gas pipe 61 in the unit is connected to the high pressure gas pipe via the high pressure gas pipe service valve 23B. 7 is connected.
Capillary tubes 62 and 63 are connected to the third port R and the fourth port S of the first four-way valve 60, respectively, and the other ends of these capillary tubes 62 and 63 are connected to the refrigerant suction branch pipe 28A. Note that the third port R and the fourth port S may be simply closed with a sealing plug or the like.

In this configuration, the first outdoor unit 2 can be connected to three inter-unit piping 5 by changing the piping configuration of a so-called two-pipe outdoor unit.
Specifically, the first unit case 23 is provided with a high-pressure gas pipe service valve 23B, a first four-way valve 60 is provided, and the high-pressure gas pipe service valve 23B and the second port Q of the first four-way valve 60 are provided in the unit. The high pressure gas pipe 61 is connected, and the first port P of the first four-way valve 60 and the refrigerant discharge pipe 25 are connected by the refrigerant discharge branch pipe 25A. Further, the third port R and the fourth port S of the first four-way valve 60 are connected to the refrigerant suction branch pipe 28A via capillary tubes 62 and 63, respectively.
In the two-pipe outdoor unit, a gas pipe service valve (corresponding to the low-pressure gas pipe service valve 23A in this configuration) and a four-way valve (corresponding to the fourth port δ of the second four-way valve 24 in this configuration). ), The low pressure gas pipe service valve 23A and the refrigerant suction pipe 28 are connected via the refrigerant suction branch pipe 28A, and the fourth port δ of the second four-way valve 24 is connected via the capillary tube 46. And connected to the refrigerant suction pipe 28.
In this manner, the first outdoor unit 2 that can be connected to the three inter-unit pipes 5 can be easily obtained by providing the first four-way valve 60 in the existing two-pipe type outdoor unit and changing a part of the pipe configuration. Compared to the case of developing a three-pipe outdoor unit independently, the development period can be shortened and the production line can be shared, and the production cost can be reduced. it can. In addition, since the first outdoor unit is configured based on a so-called two-pipe outdoor unit, the first outdoor unit 2 has a simplified piping configuration compared to the conventional three-pipe outdoor unit. As a result, the device itself can be made compact.

  The first outdoor unit 2 includes pressure sensors (not shown) for detecting the suction pressure and discharge pressure of the first compressor 20 and the refrigerant pressure in the first outdoor heat exchangers 21 and 21, respectively. In addition to the temperature sensors (not shown) that detect the inlet / outlet temperatures and the outside air temperatures of the first outdoor heat exchangers 21 and 21, etc., the detection results of these sensors are input to control the first outdoor unit 2. A first outdoor control device (not shown) is provided.

The second outdoor unit 3 includes a variable capacity second compressor (DC inverter compressor) 30, a four-way valve 31, a second outdoor heat exchanger 32, and a second expansion valve (second outdoor expansion valve) 33. And a second unit case 34 that accommodates them, and the second unit case 34 is connected to devices in the second unit case 34 and two pipes, a gas pipe 35 and a liquid pipe 36, respectively. A gas pipe service valve 34A and a second liquid pipe service valve 34B are provided.
The second outdoor unit 3 is an existing two-pipe type (two-way) outdoor unit that can perform a cooling operation or a heating operation by switching the four-way valve 31.
The refrigerant discharge pipe 37 of the second compressor 30 is connected to the four-way valve 31 via a check valve 38, and one end of the second outdoor heat exchanger 32 is connected to the four-way valve 31 via a unit internal gas pipe 39. It is connected to the. A second unit internal liquid pipe 40 is connected to the other end of the second outdoor heat exchanger 32, and the second unit internal liquid pipe 40 is connected to the second liquid pipe service valve 34 </ b> B via the second expansion valve 33. It is connected to the. A liquid pipe 36 is connected to the second liquid pipe service valve 34B.
On the other hand, the refrigerant suction pipe 41 of the second compressor 30 is connected to a four-way valve 31, and a gas pipe service valve 34 </ b> A is connected to the four-way valve 31 via an in-unit gas pipe 42. A gas pipe 35 is connected to the gas pipe service valve 34A.

The second outdoor unit 3 includes pressure sensors (not shown) for detecting the suction pressure and discharge pressure of the second compressor 30 and the refrigerant pressure in the second outdoor heat exchanger 32, respectively, and the second outdoor unit 3. A temperature sensor (not shown) for detecting the inlet / outlet temperature and the outside air temperature of the heat exchanger 32 is disposed, and the second outdoor control device that controls the second outdoor unit 3 by inputting the detection results of these sensors. (Not shown).
In this embodiment, the 1st outdoor unit 2 functions as a main | base station, and the 1st outdoor control apparatus of this 1st outdoor unit 2 is based on the user instruction input via the remote controller which abbreviate | omitted illustration. It communicates with an outdoor control apparatus and each indoor control apparatus, and performs operation control of this air conditioning apparatus 1 whole.

By the way, since the second outdoor unit 3 includes two pipes of the gas pipe 35 and the liquid pipe 36 extending from the second unit case 34, the two pipes are connected to the three inter-unit pipes 5 as they are. I can't. For this reason, in this configuration, the air conditioner 1 includes the valve body kit 50 that selectively connects the gas pipe 35 extending from the second outdoor unit 3 to the high-pressure gas pipe 7 or the low-pressure gas pipe 6 of the inter-unit pipe 5. Prepare. The valve body kit 50 includes a single third four-way valve 51 as a flow path switching valve and a case body 52 that accommodates the third four-way valve 51, and the gas pipe 35 described above is provided in the case body 52. A connection port to which the high pressure gas pipe 7 and the low pressure gas pipe 6 are connected is formed. A liquid pipe 36 extending from the second unit case 34 is connected to the liquid pipe 8 of the inter-unit pipe 5.
The valve body kit 50 is a dedicated kit for connecting the second outdoor unit 3, which is an existing two-pipe outdoor unit, to the inter-unit pipe 5. One valve unit 50 is provided for each second outdoor unit 3. A valve body kit 50 is provided. According to this, since the existing two-pipe type second outdoor unit 3 can be connected to the inter-unit pipe 5 by using the valve body kit 50, it is connected to the three-pipe type air conditioner 1. Some of the outdoor units that are used can be replaced with expensive three-pipe outdoor units that have complicated piping configurations and can be replaced with existing two-pipe outdoor units that are inexpensive, and the entire air conditioner 1 The price of can be reduced.
Further, the valve body kit 50 is disposed outside the second unit case 34 of the second outdoor unit 3. According to this, the existing two-pipe type second outdoor unit 3 can be used as it is in the three-pipe type air conditioner 1 without changing the pipe configuration. Can be simplified.

The third four-way valve 51 of the valve body kit 50 is provided with four ports A to D, the gas pipe 35 is connected to the first port A, and the low pressure gas pipe 6 is connected to the second port B. The high pressure gas pipe 7 is connected to the third port C, the capillary tube 53 is connected to the fourth port D, and the other end of the capillary tube 53 is connected to the low pressure gas pipe 6. The fourth port D may be simply closed with a sealing plug or the like without connecting the low-pressure gas pipe 6 to the fourth port D via the capillary tube 53.
The operation of the third four-way valve 51 of the valve body kit 50 is controlled by the second outdoor control device of the second outdoor unit 3.

Next, the operation of the air conditioner 1 will be described.
When all the indoor units 4A to 4D are cooled at the same time, the low pressure gas pipe 6, the high pressure gas pipe 7 and the liquid pipe 8 are all used. In this case, as shown in FIG. 1, in the first outdoor unit 2, the second four-way valve 24 guides the refrigerant discharged from the first compressor 20 to the first outdoor heat exchangers 21, 21 (second switching position). That is, the first port α and the second port β of the second four-way valve 24 are switched to positions where the third port γ and the fourth port δ communicate with each other, and the electromagnetic on-off valve 27, the first expansion valve 22, 22 is opened. In addition, the position where the first four-way valve 60 blocks communication between the refrigerant discharge pipe 25 of the first compressor 20 and the high-pressure gas pipe 7, that is, the first port P, the fourth port S, and the first port of the first four-way valve 60. The 2 port Q and the third port R can be switched to a position where they communicate with each other.
In the second outdoor unit 3, the four-way valve 31 is switched to the cooling operation position in which the refrigerant discharged from the second compressor 30 is guided to the second outdoor heat exchanger 32. In the indoor units 4A and 4B, the first on-off valves 15A and 15B are closed, the second on-off valves 16A and 16B are opened, and in the indoor units 4C and 4D, the first on-off valves 15C and 15D are opened. The two on-off valves 16C and 16D are closed. In the valve body kit 50, the third four-way valve 51 is switched to a position where the first port A and the third port C and the second port B and the fourth port D communicate with each other.

Thereby, the refrigerant discharged from the first compressor 20 sequentially flows to the refrigerant discharge pipe 25, the second four-way valve 24, the in-unit gas pipe 26, and the first outdoor heat exchangers 21 and 21, and this first outdoor After being condensed and liquefied by the heat exchangers 21, 21, it flows into the liquid pipe 8 of the inter-unit pipe 5 through the first unit liquid pipe 29. On the other hand, the refrigerant discharged from the second compressor 30 sequentially flows to the refrigerant discharge pipe 37, the four-way valve 31, and the second outdoor heat exchanger 32, and is condensed and liquefied by the second outdoor heat exchanger 32. It flows into the liquid pipe 8 of the inter-unit pipe 5 through the pipe 36 and merges with the refrigerant that has flowed out of the first outdoor unit 2 in the liquid pipe 8.
The liquid refrigerant flowing through the liquid pipe 8 is distributed to the indoor expansion valves 11A to 11D of the indoor units 4A to 4D, where the pressure is reduced. And all the indoor units 4A-4D are cooled simultaneously by evaporating and evaporating the decompressed refrigerant | coolant in each indoor heat exchanger 10A-10D.
The refrigerant evaporated by the indoor heat exchangers 10A and 10B of the indoor units 4A and 4B flows into the low pressure gas pipe 6 through the second on-off valves 16A and 16B and the low pressure gas branch pipes 14A and 14B, respectively. The refrigerant flowing through the low pressure gas pipe 6 flows into the first outdoor unit 2 and is sucked into the first compressor 20 through the refrigerant suction branch pipe 28A and the refrigerant suction pipe 28.
On the other hand, the refrigerant evaporated by the indoor heat exchangers 10C and 10D of the indoor units 4C and 4D flows into the high-pressure gas pipe 7 through the first on-off valves 15C and 15D and the low-pressure gas branch pipes 14C and 14D, respectively. The refrigerant flowing through the high pressure gas pipe 7 flows into the second outdoor unit 3 through the third four-way valve 51 and the gas pipe 35 of the valve body kit 50, and enters the second compressor 30 through the four-way valve 31 and the refrigerant suction pipe 41. Inhaled.

Thus, in this configuration, the first outdoor unit 2 is switched to the refrigerant through the low-pressure gas pipe 6 by switching the first four-way valve 60 of the first outdoor unit 2 and the third four-way valve 51 of the valve body kit 50. The refrigerant can be returned to the second outdoor unit 3 through the high-pressure gas pipe 7. According to this, since the return pipe of the refrigerant can be separately provided for each outdoor unit, the low-pressure gas pipe 6 and the high-pressure gas pipe 7 have a flow rate of refrigerant flowing through the low-pressure gas pipe 6 and the high-pressure gas pipe 7. The pipe diameter can be made relatively thick, and the pressure loss of the refrigerant in the low pressure gas pipe 6 and the high pressure gas pipe 7 can be suppressed.
For this reason, when all the indoor units 4A to 4D are in the cooling operation, the first outdoor unit 2 and the second outdoor unit 3 are suppressed by suppressing the pressure loss of the refrigerant in the low pressure gas pipe 6 and the high pressure gas pipe 7. It is possible to prevent a decrease in the suction pressure of the first compressor 20 and the second compressor 30 and thus prevent a decrease in cooling capacity.
In this case, the capacity of the first compressor 20 of the first outdoor unit 2 is at least half that of all the compressors included in the air conditioner 1, that is, the second compressor 30 of the second outdoor unit 3. Therefore, the amount of refrigerant discharged from the first compressor 20 is larger than the amount of refrigerant discharged from the second compressor 30. For this reason, it is desirable to connect the first compressor 20 with a low-pressure gas pipe 6 having a diameter larger than that of the high-pressure gas pipe 7.

  In this configuration, the indoor units 4A to 4D appropriately switch the first on-off valves 15A to 15D and the second on-off valves 16A to 16D, so that the refrigerant evaporated in the indoor heat exchangers 10A to 10D flows. The piping can be selected as the low pressure gas pipe 6 or the high pressure gas pipe 7. According to this, the outdoor unit which performs cooling operation corresponding to indoor unit 4A-4D can be selected. For this reason, since the evaporation temperatures of the indoor units 4A to 4D can be made different according to the outdoor units, for example, by increasing the evaporation temperature of the indoor units with less load, the outdoor units connected to these indoor units Driving efficiency can be increased.

When all the indoor units 4A to 4D are heated at the same time, the low-pressure gas pipe 6 is put into a resting state. In this case, as shown in FIG. 2, in the first outdoor unit 2, the second four-way valve 24 is in a position (first switching position) where the first outdoor heat exchangers 21, 21 and the refrigerant suction pipe 28 communicate with each other, that is, The second four-way valve 24 is switched to a position where the first port α and the fourth port δ and the second port β and the third port γ communicate with each other, and the electromagnetic on-off valve 27 is opened, and the first expansion valve 22 is opened. , 22 are adjusted in opening according to the air conditioning load. Further, the position where the first four-way valve 60 communicates with the refrigerant discharge pipe 25 of the first compressor 20 and the high-pressure gas pipe 7, that is, the first port P, the second port Q, and the third port R of the first four-way valve 60. And the fourth port S can be switched to a position where they communicate with each other.
In the second outdoor unit 3, the four-way valve 31 is switched to the heating operation position in which the refrigerant discharged from the second compressor 30 is guided to the gas pipe 35. In all the indoor units 4A to 4D, the first on-off valves 15A to 15D are opened, and the second on-off valves 16A to 16D are closed. Further, in the valve body kit 50, the third four-way valve 51 is switched to a position where the first port A and the third port C and the second port B and the fourth port D communicate with each other.
Thereby, the refrigerant discharged from the first compressor 20 flows into the high-pressure gas pipe 7 of the inter-unit pipe 5 through the refrigerant discharge pipe 25, the refrigerant discharge branch pipe 25A, the first four-way valve 60, and the high-pressure gas pipe 61 in the unit. . On the other hand, the refrigerant discharged from the second compressor 30 passes through the refrigerant discharge pipe 37, the four-way valve 31, the unit internal gas pipe 42, the gas pipe 35, and the inter-unit pipe 5 through the third four-way valve 51 of the valve body kit 50. The refrigerant flows into the high-pressure gas pipe 7 and merges with the refrigerant that has flowed out of the first outdoor unit 2 in the high-pressure gas pipe 7.
The gas refrigerant flowing through the high-pressure gas pipe 7 is distributed to the high-pressure gas branch pipes 13A to 13D of the indoor units 4A to 4D, and then flows to the first on-off valves 15A to 15D and the indoor heat exchangers 10A to 10D. Each is condensed and liquefied. The liquefied liquid refrigerant flows into the liquid pipe 8 through the liquid branch pipes 18 </ b> A to 18 </ b> D, and is divided into two by the liquid pipe 8.
One refrigerant flows into the first outdoor unit 2 and is distributed to the first expansion valves 22 and 22 where the pressure is reduced. The decompressed refrigerant evaporates and vaporizes in the first outdoor heat exchangers 21 and 21, and then merges in the unit gas pipe 26, and passes through the second four-way valve 24 and the refrigerant suction pipe 28 to the first compressor 20. Inhaled. The other refrigerant flows into the second outdoor unit 3 through the liquid pipe 36 and is decompressed by the second expansion valve 33. The decompressed refrigerant is evaporated and evaporated in the second outdoor heat exchanger 32 and then sucked into the second compressor 30 through the four-way valve 31 and the refrigerant suction pipe 41. Thus, all the indoor units 4A to 4D are simultaneously heated by the indoor heat exchangers 10A to 10D acting as condensers.

In the case where the indoor units 4A to 4D are operated mainly in cooling and cooling, for example, the indoor units 4A to 4C are cooled and the indoor unit 4D is heated, the low pressure gas pipe 6, the high pressure gas pipe 7 and the liquid pipe All 8 are used.
In this case, as shown in FIG. 3, in the first outdoor unit 2, the second four-way valve 24 is switched to the first switching position, and the first four-way valve 60 is connected to the refrigerant discharge pipe 25 of the first compressor 20 and the high pressure. The position is communicated with the gas pipe 7, that is, the position where the first port P and the second port Q of the first four-way valve 60 and the third port R and the fourth port S communicate with each other.
Further, both the first expansion valves 22 and 22 are closed, and the refrigerant does not flow through the first outdoor heat exchangers 21 and 21. This is because the first outdoor unit 2 takes charge of the cooling load in the indoor units 4A to 4C that balances the heating load in the indoor unit 4D, and the second outdoor unit 3 takes charge of the excess cooling load to form a refrigeration cycle. Because.
In the second outdoor unit 3, the four-way valve 31 is switched to the cooling operation position in which the refrigerant discharged from the second compressor 30 is guided to the second outdoor heat exchanger 32. In the indoor units 4A to 4C, the first on-off valves 15A to 15C are closed, the second on-off valves 16A to 16C are opened, and in the indoor unit 4D, the first on-off valve 15D is opened and the second on-off valves are opened. Valve 16D is closed. In the valve kit 50, the third four-way valve 51 is switched to a position where the first port A and the second port B and the third port C and the fourth port D communicate with each other.

Thereby, the refrigerant discharged from the first compressor 20 flows into the indoor unit 4D through the refrigerant discharge pipe 25, the refrigerant discharge branch pipe 25A, the first four-way valve 60, the high-pressure gas pipe 61 in the unit, and the high-pressure gas pipe 7. . The refrigerant flowing into the indoor unit 4D flows to the indoor heat exchanger 10D through the high-pressure gas branch pipe 13D and the first on-off valve 15D, where it is condensed and liquefied, and then flows into the liquid pipe 8 through the liquid branch pipe 18D. To do.
On the other hand, the refrigerant discharged from the second compressor 30 sequentially flows to the refrigerant discharge pipe 37, the four-way valve 31, and the second outdoor heat exchanger 32, and is condensed and liquefied by the second outdoor heat exchanger 32. It flows into the liquid pipe 8 of the inter-unit pipe 5 through the pipe 36 and merges with the refrigerant that has flowed out of the first outdoor unit 2 in the liquid pipe 8.
The liquid refrigerant flowing through the liquid pipe 8 is distributed to the indoor expansion valves 11A to 11C of the indoor units 4A to 4C, where the pressure is reduced. The decompressed refrigerant evaporates and vaporizes in each of the indoor heat exchangers 10A to 10C, and then flows into the low pressure gas pipe 6 through the second on-off valves 16A to 16C and the low pressure gas branch pipes 14A to 14C, respectively. The pipe 6 distributes it in two.
One refrigerant flows into the first outdoor unit 2 and is sucked into the first compressor 20 through the refrigerant suction branch pipe 28 </ b> A and the refrigerant suction pipe 28. The other refrigerant flows into the second outdoor unit 3 through the third four-way valve 51 and the gas pipe 35 of the valve body kit 50 and is sucked into the second compressor 30 through the four-way valve 31 and the refrigerant suction pipe 41. . In this way, the indoor units 4A to 4C are each cooled by the indoor heat exchangers 10A to 10C acting as evaporators, and the indoor unit 4D is heated by the other indoor heat exchanger 10D acting as a condenser.

  In this configuration, the second outdoor unit 3 is connected to the inter-unit pipe 5 via the valve body kit 50, and the refrigerant condensed in the second outdoor heat exchanger 32 of the second outdoor unit 3 and the indoor heat exchanger The refrigerant condensed in 10D merges in the liquid pipe 8. For this reason, when performing the cooling and heating mixed operation, the condensation pressure (condensation temperature) can be set independently in the indoor heat exchanger 10D and the second outdoor heat exchanger 32 acting as a condenser, for example, When the outside air temperature is low as in winter, the condensation pressure of the second outdoor heat exchanger 32 can be kept lower than the condensation pressure of the indoor heat exchanger 10D, and the work load (consumption) of the second compressor 30 can be reduced. (Electric power) can be reduced.

When the cooling load of the indoor units 4A to 4C increases and cannot be covered by the second outdoor heat exchanger 32 of the second outdoor unit 3, the electromagnetic on-off valve 27 is closed in the first outdoor unit 2. The first expansion valve 22 on the in-unit branch gas pipe 26A not provided with the electromagnetic opening / closing valve 27 is opened, and a part of the refrigerant discharged from the first compressor 20 is transferred to the first outdoor heat exchanger 21. By guiding, the first outdoor heat exchanger 21 can act as a condenser.
In this configuration, the first outdoor unit 2 includes two first outdoor heat exchangers 21 and 21 arranged side by side, and opens and closes the electromagnetic on-off valve 27, whereby refrigerant is supplied to each first outdoor heat exchanger 21, The first outdoor heat exchanger 21 used for the air conditioning operation by controlling the operation of the electromagnetic on-off valve 27 according to the load balance between the cooling load and the heating load during the cooling and heating mixed operation, Since the number of 21 can be changed, the operation efficiency during the air conditioning operation can be improved.

In the case where the indoor units 4A to 4D are mainly operated for heating and cooling and heating, for example, when the indoor unit 4A is for cooling operation and the indoor units 4B to 4D are for heating operation, the low pressure gas pipe 6, the high pressure gas pipe 7 and the liquid pipe are used. All 8 are used.
In this case, as shown in FIG. 4, in the first outdoor unit 2, the second four-way valve 24 is switched to the first switching position, and the first expansion valves 22 and 22 are both closed, so that the first outdoor heat exchanger No refrigerant flows through 21 and 21. Further, the position where the first four-way valve 60 communicates with the refrigerant discharge pipe 25 of the first compressor 20 and the high-pressure gas pipe 7, that is, the first port P, the second port Q, and the third port R of the first four-way valve 60. And the fourth port S can be switched to a position where they communicate with each other.
In the second outdoor unit 3, the four-way valve 31 is switched to the heating operation position in which the refrigerant discharged from the second compressor 30 is guided to the gas pipe 35. In the indoor unit 4A, the first on-off valve 15A is closed and the second on-off valve 16A is opened. In the indoor units 4B to 4D, the first on-off valves 15B to 15D are opened, and the second on-off valve 16B. ~ 16D is closed. Further, in the valve body kit 50, the third four-way valve 51 is switched to a position where the first port A and the third port C and the second port B and the fourth port D communicate with each other.

Thereby, the refrigerant discharged from the first compressor 20 flows into the high-pressure gas pipe 7 of the inter-unit pipe 5 through the refrigerant discharge pipe 25, the refrigerant discharge branch pipe 25A, the first four-way valve 60, and the high-pressure gas pipe 61 in the unit. . On the other hand, the refrigerant discharged from the second compressor 30 passes through the refrigerant discharge pipe 37, the four-way valve 31, the unit internal gas pipe 42, the gas pipe 35, and the inter-unit pipe 5 through the third four-way valve 51 of the valve body kit 50. The refrigerant flows into the high-pressure gas pipe 7 and merges with the refrigerant that has flowed out of the first outdoor unit 2 in the high-pressure gas pipe 7.
The gas refrigerant flowing through the high-pressure gas pipe 7 is distributed to the high-pressure gas branch pipes 13B to 13D of the indoor units 4B to 4D, and then flows to the first on-off valves 15B to 15D and the indoor heat exchangers 10B to 10D. Each is condensed and liquefied. The liquefied liquid refrigerant flows into the liquid pipe 8 through the liquid branch pipes 18B to 18D.
A part of the liquid refrigerant that has flowed into the liquid pipe 8 flows into the indoor unit 4A and is decompressed by the indoor expansion valve 11A of the indoor unit 4A, and the decompressed refrigerant is evaporated by the indoor heat exchanger 10A. . The vaporized gas refrigerant flows into the first outdoor unit 2 through the second on-off valve 16A, the low pressure gas branch pipe 14A, and the low pressure gas pipe 6, and passes through the refrigerant suction branch pipe 28A and the refrigerant suction pipe 28 to the first compressor. 20 is inhaled.
On the other hand, the remainder of the liquid refrigerant flowing into the liquid pipe 8 flows into the second outdoor unit 3 through the liquid pipe 36 and is decompressed by the second expansion valve 33. The decompressed refrigerant is evaporated and evaporated in the second outdoor heat exchanger 32 and then sucked into the second compressor 30 through the four-way valve 31 and the refrigerant suction pipe 41. In this way, the indoor unit 4A is cooled by the indoor heat exchanger 10A acting as an evaporator, and the indoor units 4B to 4D are heated by the other indoor heat exchangers 10B to 10D acting as condensers.

  In this structure, since the 2nd outdoor unit 3 is connected to the inter-unit piping 5 via the valve body kit 50, the refrigerant | coolant condensed with each indoor heat exchanger 10B-10D of each indoor unit 4B-4D. A part can be led to the indoor heat exchanger 10 </ b> A of the indoor unit 4 </ b> A, and the rest can be led to the second outdoor heat exchanger 32 of the second outdoor unit 3. For this reason, in the case of the cooling / heating mixed operation, the evaporation pressure (evaporation temperature) can be set independently in the indoor heat exchanger 10A and the second outdoor heat exchanger 32 acting as an evaporator. For this reason, for example, when the outside air temperature is low as in winter, the evaporation temperature of the indoor heat exchanger 10D is set to be higher than the evaporation temperature of the second outdoor heat exchanger 32 that decreases with the outside air temperature. An appropriate temperature higher than the evaporation temperature of the heat exchanger 32 can be set. As a result, since the evaporation temperature of the indoor heat exchanger 10D is prevented from lowering due to the influence of the outside air temperature as in the prior art, a means for preventing the indoor heat exchanger 10D from freezing is unnecessary. Become.

  Further, when the heating load of the indoor units 4B to 4D increases and cannot be covered by the second outdoor heat exchanger 32 of the second outdoor unit 3, the electromagnetic on-off valve 27 is closed in the first outdoor unit 2. The first expansion valve 22 on the in-unit branch gas pipe 26A not provided with the electromagnetic opening / closing valve 27 is opened, and a part of the refrigerant discharged from the first compressor 20 is transferred to the first outdoor heat exchanger 21. By guiding, the first outdoor heat exchanger 21 can act as an evaporator.

As described above, according to the present embodiment, the first compressor 20, the first outdoor heat exchanger 21, and the first expansion valve 22 are provided, and the high pressure gas pipe 7, the low pressure gas pipe 6, and the liquid pipe 8 are included. A three-pipe type first outdoor unit 2 connected to three inter-unit pipes 5 and a plurality of indoor units 4A to 4D provided with indoor heat exchangers 10A to 10D. In the air conditioner 1 configured to enable 4D to perform cooling operation or heating operation at the same time, or to perform a mixture of these cooling operation and heating operation, the second compressor 30 and the second outdoor heat exchanger A second outdoor unit 3 having two pipes of a gas pipe 35 and a liquid pipe 36, each having a gas pipe 35 and a second expansion valve 33. The liquid pipe 36 of the second outdoor unit 3 is connected to the liquid pipe of the inter-unit pipe 5. 8 and the second outdoor unit And a valve body kit 50 having a third four-way valve 51 for selectively connecting the gas pipe 35 of the third unit 3 to the high-pressure gas pipe 7 or the low-pressure gas pipe 6 of the inter-unit pipe 5. When the first four-way valve 60 that allows the refrigerant discharge pipe 25 of the first compressor 20 and the high-pressure gas pipe 7 to communicate with each other is provided, and all the indoor units 4A to 4D are simultaneously operated for cooling, the first four-way valve 60 is The communication between the refrigerant discharge pipe 25 and the high-pressure gas pipe 7 is blocked, and the third four-way valve 51 is switched to connect the gas pipe 35 to the high-pressure gas pipe 7.
Therefore, the refrigerant is returned to the first outdoor unit 2 through the low-pressure gas pipe 6 by switching the first four-way valve 60 of the first outdoor unit 2 and the third four-way valve 51 of the valve body kit 50, respectively. The refrigerant can be returned to the second outdoor unit 3 through the high-pressure gas pipe 7. According to this, since the return pipe of the refrigerant can be separately provided for each outdoor unit, the low-pressure gas pipe 6 and the high-pressure gas pipe 7 have a flow rate of refrigerant flowing through the low-pressure gas pipe 6 and the high-pressure gas pipe 7. The pipe diameter can be made relatively thick, and the pressure loss of the refrigerant in the low pressure gas pipe 6 and the high pressure gas pipe 7 can be suppressed. For this reason, when carrying out the cooling operation of all the indoor units 4A-4D, the fall of the suction pressure of the 1st compressor 20 in the 1st outdoor unit 2 and the 2nd outdoor unit 3 and the 2nd compressor 30 can be prevented. Therefore, it is possible to prevent the cooling capacity from being lowered.
Moreover, in each indoor unit 4A-4D, the 1st on-off valve 15A-15D and the 2nd on-off valve 16A-16D are switched suitably, and the piping into which the refrigerant | coolant which evaporated in each indoor heat exchanger 10A-10D flows in is sent to low pressure gas The pipe 6 or the high-pressure gas pipe 7 can be selected, and the outdoor unit that performs the cooling operation can be selected corresponding to the indoor units 4A to 4D. For this reason, since the evaporation temperatures of the indoor units 4A to 4D can be varied according to the outdoor units, for example, by raising the evaporation temperature of the indoor unit with a small load, the outdoor units connected to these indoor units Driving efficiency can be increased.

  Further, according to the present embodiment, the first four-way valve 60 connects the refrigerant discharge branch pipe 25A branched from the refrigerant discharge pipe 25 to the first port P, and the high pressure gas pipe 61 in the unit to the second port Q. Since the high pressure gas pipe 7 is connected and the refrigerant suction branch pipe 28A connected to the low pressure gas pipe 6 is connected to the third port R and the fourth port S via the capillary tubes 62 and 63, respectively, the first four-way valve The refrigerant discharge pipe 25 and the high-pressure gas pipe 7 can be communicated or blocked at a low cost with a simple configuration such as interposing 60.

Further, according to the present embodiment, the first outdoor unit 2 includes the second four-way valve 24 between the first compressor 20 and the first outdoor heat exchangers 21, 21. The high pressure gas pipe 7 is connected to the refrigerant discharge branch pipe 25A branched from between the first compressor 20 via the first four-way valve 60 and the high pressure gas pipe 61 in the unit, and the second four-way valve 24 and the first compressor. The low pressure gas pipe 6 is connected to the refrigerant suction branch pipe 28A branched from between 20, and the second four-way valve 24 communicates the low pressure gas pipe 6 and the first outdoor heat exchanger 21 at the first switching position. In order to connect the first compressor 20 and the first outdoor heat exchanger 21 at the two switching positions, the first outdoor unit 2 connected to the three inter-unit pipes 5 is connected to the compressor, the four-way valve, and the outdoor heat exchange. The pipe configuration of the existing outdoor unit of the so-called two-pipe type that has a vessel is partially changed In can be constructed, it is possible to reduce the production cost in comparison with the case of independently developed an outdoor unit of three pipes expression.
Further, since the first outdoor unit 2 is configured based on the so-called two-pipe outdoor unit, the first outdoor unit 2 is made more compact than the conventional three-pipe outdoor unit. Can be realized.

  Further, according to the present embodiment, the valve body kit 50 includes a single third four-way valve 51, the gas pipe 35 is connected to the first port A of the third four-way valve 51, and the second port B is connected. Since the low pressure gas pipe 6 is connected, the high pressure gas pipe 7 is connected to the third port C, and the low pressure gas pipe 6 is connected to the fourth port D via the capillary tube 53, the third four-way valve 51 is interposed. With this configuration, the gas pipe 35 of the second outdoor unit 3 can be alternatively connected to the high-pressure gas pipe 7 or the low-pressure gas pipe 6 of the inter-unit pipe 5 and is constituted by a so-called two-pipe type outdoor unit. The second outdoor unit 3 can be connected to the three-pipe type air conditioner 1.

  According to this embodiment, since the valve body kit 50 is provided outside the second unit case 34 of the second outdoor unit 3, the existing two-pipe outdoor unit is configured as a pipe configuration as the second outdoor unit 3. Can be used without change, and the configuration of the three-pipe type air conditioner 1 can be simplified.

  Moreover, according to this embodiment, since the capacity | capacitance of the 1st compressor 20 is provided with the capacity | capacitance of at least half of all the compressors with which the air conditioning apparatus 1 is provided, the cooling load and heating during cooling / heating mixed operation When the load is 50%: 50%, the air conditioning operation can be performed using the first outdoor unit 2 including the first compressor 20, and the cooling load or the heating load is increased so that the load balance is increased. When it is changed, the second outdoor unit 3 can take charge of the surplus load of the cooling load or the heating load. For this reason, the air conditioning operation with the load balance can be realized regardless of how the load balance between the cooling load and the heating load during the cooling / heating mixed operation changes.

As mentioned above, although this invention was demonstrated based on the said embodiment, this invention is not limited to this. For example, in the present embodiment, the first four-way valve 60 is provided as a valve body that allows the refrigerant discharge pipe 25 of the first compressor 20 and the high-pressure gas pipe 6 to communicate with each other. Instead of the first four-way valve 60, an electromagnetic opening / closing valve may be provided.
In addition, the valve body kit 50 is configured to provide the third four-way valve 51 as a flow path switching valve, but is not limited thereto, and may be configured by combining a plurality of electromagnetic on-off valves.

DESCRIPTION OF SYMBOLS 1 Air conditioning apparatus 2 1st outdoor unit 3 2nd outdoor unit 4A-4D Indoor unit 5 Inter-unit piping 6 Low pressure gas pipe 7 High pressure gas pipe 8 Liquid pipe 20 1st compressor 21 1st outdoor heat exchanger 22 1st expansion Valve (first outdoor expansion valve)
24 Second four-way valve 25 Refrigerant discharge pipe 25A Refrigerant discharge branch pipe 26 In-unit gas pipe 26A In-unit branch gas pipe 28 Refrigerant suction pipe 28A Refrigerant suction branch pipe 30 Second compressor 31 Four-way valve 32 Second outdoor heat exchanger 33 Second expansion valve (second outdoor expansion valve)
35 Gas pipe 36 Liquid pipe 46, 53, 62, 63 Capillary tube 50 Valve body kit 51 Third four-way valve (flow path switching valve)
52 Case body 60 First four-way valve 61 High pressure gas pipe in unit

Claims (6)

A first outdoor unit including a first compressor, a first outdoor heat exchanger and a first outdoor expansion valve, and a plurality of indoor units including an indoor heat exchanger are connected by inter-unit piping, and the first One end of the outdoor heat exchanger is alternatively branched and connected to the refrigerant discharge pipe and the refrigerant suction pipe of the first compressor, and the inter-unit pipe is a high-pressure gas pipe connected to the refrigerant discharge pipe; A low-pressure gas pipe connected to the refrigerant suction pipe and a liquid pipe connected to the other end of the first outdoor heat exchanger, and one end of the indoor heat exchanger is connected to the high-pressure gas pipe and the The other end of the indoor heat exchanger is connected to the low pressure gas pipe via the liquid branch pipe so that the plurality of indoor units can be simultaneously operated for cooling or heating. Or, these cooling operation and heating operation can be implemented together. In made air conditioner,
A second outdoor unit connected by two pipes, a gas pipe and a liquid pipe, having a second compressor, a second outdoor heat exchanger, and a second outdoor expansion valve, and the liquid pipe of the second outdoor unit A valve body kit having a flow path switching valve that connects to the liquid pipe of the inter-unit pipe and selectively connects the gas pipe of the second outdoor unit to the high-pressure gas pipe or the low-pressure gas pipe of the inter-unit pipe. Prepared,
The first outdoor unit includes a valve body that enables communication between the refrigerant discharge pipe and the high-pressure gas pipe.
When simultaneously cooling the indoor unit, the valve element cuts off the communication between the refrigerant discharge pipe and the high pressure gas pipe, and the flow path switching valve connects the gas pipe to the high pressure gas pipe. An air conditioner characterized by being switched to.   The valve body is a single first four-way valve having four ports, the refrigerant discharge pipe is connected to the first port of the first four-way valve, the high-pressure gas pipe is connected to the second port, The third port is closed, or the low pressure gas pipe is connected to the third port via a capillary tube, and the fourth port is closed, or the fourth port is connected via a capillary tube, The air conditioner according to claim 1, wherein the low-pressure gas pipe is connected. The first outdoor unit includes a second four-way valve between the first compressor and the first outdoor heat exchanger, and a refrigerant discharge branch pipe branched from between the second four-way valve and the first compressor. Connecting the high-pressure gas pipe via the valve body, connecting the low-pressure gas pipe to a refrigerant suction branch pipe branched from between the second four-way valve and the first compressor;
The second four-way valve communicates the low pressure gas pipe and the first outdoor heat exchanger at a first switching position, and communicates the first compressor and the first outdoor heat exchanger at a second switching position. The air conditioner according to claim 1 or 2, characterized by:   The valve body kit includes a single third four-way valve as the flow path switching valve, the gas pipe is connected to a first port of the third four-way valve, and the low-pressure gas pipe is connected to a second port. The high pressure gas pipe is connected to the third port and the fourth port is closed, or the low pressure gas pipe is connected to the fourth port via a capillary tube. The air conditioning apparatus in any one of thru | or 3.   The air conditioning apparatus according to any one of claims 1 to 4, wherein the valve body kit is provided outside a housing of the second outdoor unit.   The air conditioner according to any one of claims 1 to 5, wherein the capacity of the first compressor is configured to include at least half of the capacity of all the compressors included in the air conditioner.

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