Outdoor unit of air conditioner, and air conditioner

Abstract

Provided are an outdoor unit of an air conditioner and an air conditioner in which connections between a plurality of outdoor heat exchangers, the discharge side of a compressor, and the suction side of a compressor can be switched and which have excellent piping installation routes. The present invention comprises: a compressor (2) that compresses refrigerant; a main heat exchanger (31a) that exchanges heat between the refrigerant and outside air; a first switching valve (12A) that sends the refrigerant from the compressor (2) to the main heat exchanger (31a) to cause the main heat exchanger (31a) to function as a condenser; an auxiliary heat exchanger (31b) that exchanges heat between the refrigerant and outside air; a second switching valve (12B) that sends the refrigerant from the compressor (2) to the auxiliary heat exchanger (31b) to cause the auxiliary heat exchanger (31b) to function as a condenser; and a third switching valve (12C) that is capable of blocking the flow of refrigerant from the compressor (2) to indoor heat exchangers (21A, 21B, ...) of all indoor units (6A, 6B, ...) to cause the main heat exchanger (31a) and the auxiliary heat exchanger (31b) to function as condensers, and capable of sending the refrigerant from the compressor (2) to the indoor heat exchanger (21A, 21B, ...) of at least one indoor unit (6A, 6B, ...) to cause the at least one indoor heat exchanger (21A) to function as a condenser. The first switching valve (12A) is closer to an end surface (101) of the main heat exchanger (31a) than the third switching valve (12C) is, and the second switching valve (12B) is closer to the end surface (101) of the main heat exchanger (31a) than the first switching valve (12A) is.

Description

Outdoor unit for air conditioner, and air conditioner

[0001] An embodiment of the present invention relates to an outdoor unit for an air conditioner, and an air conditioner.

[0002] An air conditioner is known that includes an outdoor unit, multiple indoor units, multiple switching units, a first connecting pipe, a second connecting pipe, and a third connecting pipe. The outdoor unit includes an outdoor heat exchanger and a compressor. The outdoor unit includes a first outdoor pipe that connects the outdoor heat exchanger and the first connecting pipe, a second outdoor pipe that connects the compressor and the second connecting pipe, and a third outdoor pipe that connects the compressor and the third connecting pipe. Each indoor unit includes an indoor heat exchanger.

[0003] Each switching unit includes an indoor first pipe connecting the indoor heat exchanger and the first connecting pipe, an indoor second pipe connecting the indoor heat exchanger and the second connecting pipe, an indoor third pipe connecting the indoor heat exchanger and the third connecting pipe, and an indoor third pipe valve provided on the indoor third pipe. Each indoor third pipe valve switches the connection state between the three pipes of the outdoor unit and the two pipes of the respective indoor unit.

[0004] This conventional air conditioner can perform heating operation in all indoor units or cooling operation in all indoor units, as well as performing heating operation in some indoor units and cooling operation in the remaining indoor units.

[0005] JP 2017-180882 A

[0006] Conventional air conditioners have room for improvement in the routing of piping within the outdoor unit.

[0007] Therefore, the present invention aims to provide an outdoor unit of an air conditioner or an air conditioner that is capable of switching the connection between multiple outdoor heat exchangers, the discharge side of a compressor, and the suction side of a compressor, and that has excellent piping routing.

[0008] In order to solve the above-mentioned problems, an outdoor unit of an air conditioner according to an embodiment of the present invention includes a compressor that compresses a refrigerant, a first outdoor heat exchanger that exchanges heat between the refrigerant and outdoor air, a first switching valve that connects the discharge side of the compressor to the first outdoor heat exchanger to make the first outdoor heat exchanger function as a condenser or connects the suction side of the compressor to the first outdoor heat exchanger to make the first outdoor heat exchanger function as an evaporator, a second outdoor heat exchanger that exchanges heat between the refrigerant and outdoor air, and a first switching valve that connects the discharge side of the compressor to the second outdoor heat exchanger to make the second outdoor heat exchanger function as a condenser or connects the suction side of the compressor to the second outdoor heat exchanger to make the second outdoor heat exchanger function as an evaporator. and a third switching valve that can cut off the connection between the discharge side of the compressor and the indoor heat exchangers of all indoor units to allow the outdoor first heat exchanger and the outdoor second heat exchanger to function as a condenser, or that can connect the discharge side of the compressor to the indoor heat exchanger of at least one of the indoor units to allow the indoor heat exchanger of the at least one indoor unit to function as a condenser, wherein the first switching valve is closer to the first heat exchanger than the third switching valve, and the second switching valve is closer to the first heat exchanger than the first switching valve.

[0009] It is preferable that the first switching valve, the second switching valve, and the third switching valve of the outdoor unit of the air conditioning apparatus according to the embodiment of the present invention are arranged outside the projection area in the normal direction of the end face.

[0010] In an embodiment of the present invention, it is preferable that the first outdoor heat exchanger and the second outdoor heat exchanger of the outdoor unit of the air conditioning apparatus are integrated, and that the end face of the first outdoor heat exchanger and the end face of the second outdoor heat exchanger are one continuous plane.

[0011] The first switching valve, the second switching valve, and the third switching valve of the outdoor unit of the air conditioning apparatus according to an embodiment of the present invention are four-way valves and have a first connection port connectable to a condenser and a second connection port connectable to an evaporator, and it is preferable that either the first connection port or the second connection port is blocked.

[0012] The outdoor unit of the air conditioning apparatus according to an embodiment of the present invention preferably comprises a housing that houses the compressor, the first outdoor heat exchanger, the second outdoor heat exchanger, the first switching valve, the second switching valve, and the third switching valve, and the end face of the first outdoor heat exchanger and the end face of the second outdoor heat exchanger face horizontally of the housing, and each of the first switching valve, the second switching valve, and the third switching valve preferably comprises a valve body, a valve box that houses the valve body so as to be movable horizontally, a third connection port that hangs downward from the valve box and is connected to the discharge side of the compressor, and a fourth connection port that rises above the valve box and is connected to the suction side of the compressor.

[0013] It is preferable that the housing of the outdoor unit of the air conditioning apparatus according to an embodiment of the present invention has a detachable side surface, and that the first switching valve, the second switching valve, and the third switching valve are each equipped with a pilot solenoid valve facing the inner surface of the side surface.

[0014] The outdoor unit of the air conditioning apparatus according to an embodiment of the present invention preferably includes an accumulator connected to the suction side of the compressor, the first heat exchanger being arranged above the second heat exchanger, and the first switching valve, the second switching valve, and the third switching valve being arranged above the accumulator.

[0015] In addition, in order to solve the above-mentioned problems, the air conditioning apparatus according to an embodiment of the present invention comprises the outdoor unit, a plurality of indoor units, and a plurality of switching units capable of switching the flow direction of the refrigerant flowing to the corresponding indoor units, wherein the indoor units have an outdoor expansion valve connected to the discharge side of the first heat exchanger, and each of the indoor units has an outdoor heat exchanger and an indoor expansion valve connected to the outdoor heat exchanger, and the flow directions of the refrigerant flowing to the plurality of indoor units can be made different from each other, allowing a mixture of indoor units operating in cooling mode and indoor units operating in heating mode.

[0016] Furthermore, in order to solve the above-mentioned problems, an air conditioning apparatus according to an embodiment of the present invention comprises the outdoor unit and a plurality of indoor units, wherein the indoor unit has an outdoor expansion valve connected to the discharge side of the first heat exchanger, and each of the indoor units has an outdoor heat exchanger and an indoor expansion valve connected to the outdoor heat exchanger, and one of the branches of the third switching valve is blocked so that the refrigerant is sucked into the compressor through the third switching valve during cooling operation, and the refrigerant is sent to the plurality of indoor units through the third switching valve during heating operation.

[0017] In addition, in order to solve the above-mentioned problems, an air conditioning apparatus according to an embodiment of the present invention comprises the outdoor unit and a plurality of indoor units, wherein the indoor unit has an outdoor expansion valve connected to the discharge side of the first heat exchanger, and each of the indoor units has an outdoor heat exchanger and an indoor expansion valve connected to the outdoor heat exchanger, and when the air conditioning apparatus is provided with a plurality of switching units that can switch the flow direction of the refrigerant flowing to the corresponding indoor units, it is possible to mix indoor units that perform cooling operation and indoor units that perform heating operation by making the flow directions of the refrigerant flowing to the plurality of indoor units different from each other, and when the air conditioning apparatus is not provided with a plurality of switching units, one of the branches of the third switching valve is blocked so that the refrigerant is sucked into the compressor through the third switching valve during cooling operation, and the refrigerant is sent to the plurality of indoor units through the third switching valve during heating operation, and the flow direction of the refrigerant flowing to the plurality of indoor units is unified, causing all of the indoor units to perform cooling operation or heating operation.

[0018] According to the present invention, it is possible to provide an air conditioner or an outdoor unit of an air conditioner that is capable of switching the connection between multiple outdoor heat exchangers, the discharge side of a compressor, and the suction side of a compressor, and that has excellent piping routing.

[0019] FIG. 1 is a block diagram of an air conditioner according to an embodiment of the present invention. FIG. 2 is a diagram showing a first example of a refrigerant flow in a cooling mixed operation mode of an air conditioner according to an embodiment of the present invention. FIG. 3 is a diagram showing a second example of a refrigerant flow in a cooling mixed operation mode of an air conditioner according to an embodiment of the present invention. FIG. 4 is a diagram showing an example of a refrigerant flow in a heating mixed operation mode of an air conditioner according to an embodiment of the present invention. FIG. 5 is an exploded perspective view of a first example of an outdoor unit according to an embodiment of the present invention. FIG. 6 is a front view of a first example of an outdoor unit according to an embodiment of the present invention. FIG. 7 is a schematic front view of a first example of an outdoor unit according to an embodiment of the present invention. FIG. 8 is a plan view of a first example of an outdoor unit according to an embodiment of the present invention. FIG. 9 is a perspective view of three switching valves of an outdoor unit according to an embodiment of the present invention. FIG. 10 is a schematic front view of a first comparative example of an outdoor unit according to an embodiment of the present invention. FIG. 11 is a schematic front view of a second comparative example of an outdoor unit according to an embodiment of the present invention. FIG. 12 is a plan view of a second example of an outdoor unit according to an embodiment of the present invention. FIG. 13 is a perspective view of three switching valves of an outdoor unit according to an embodiment of the present invention. FIG. 14 is a schematic front view of a third comparative example of an outdoor unit. FIG. 15 is a schematic front view of a fourth comparative example of an outdoor unit. FIG. 4 is a block diagram of a second embodiment of an air conditioning apparatus according to an embodiment of the present invention.

[0020] An embodiment of an outdoor unit for an air conditioner according to the present invention, and an embodiment of an air conditioner according to the present invention will be described with reference to Figures 1 to 18. Note that the same or corresponding components are denoted by the same reference numerals in the drawings.

[0021] FIG. 1 is a block diagram of an air conditioning apparatus according to an embodiment of the present invention.

[0022] As shown in Figure 1, the air conditioner 1 according to this embodiment is a heat recovery multi-type air conditioner. The air conditioner 1 includes at least one outdoor unit 5 having a compressor 2 that compresses a refrigerant, multiple indoor units 6A, 6B, and multiple switching units 7A, 7B, and the like that can switch the flow direction of the refrigerant through the indoor units 6A, 6B, and the like. The air conditioner 1 also includes refrigerant piping 8 that sequentially connects the outdoor unit 5, the multiple switching units 7A, 7B, and the multiple indoor units 6A, 6B, and the like, allowing the refrigerant to circulate.

[0023] The air conditioning device 1 circulates a refrigerant between the outdoor unit 5 and multiple indoor units 6A, 6B, ..., and performs full cooling operation in which the outdoor unit 5 functions as a condenser and all indoor units 6A, 6B, ... function as evaporators, and full heating operation in which the outdoor unit 5 functions as an evaporator and all indoor units 6A, 6B, ... function as condensers.

[0024] Furthermore, the air conditioning apparatus 1 can have a mixture of indoor units 6A, 6B, ... operating in cooling mode and indoor units 6A, 6B, ... operating in heating mode by mutually differing the flow directions of the refrigerant flowing through the indoor units 6A, 6B, .... The air conditioning apparatus 1 performs a cooling mixed operation in which the outdoor unit 5 functions as a condenser, some indoor units 6A, 6B function as evaporators, and the remaining indoor units 6C function as condensers, and a heating mixed operation in which the outdoor unit 5 functions as an evaporator, some indoor units 6A, 6B function as condensers, and the remaining indoor units 6C function as evaporators. The cooling mixed operation is a cooling-dominated operation in which many indoor units 6A, 6B perform cooling operation and a small number of indoor units 6C perform heating operation. The heating mixed operation is a heating-dominated operation in which many indoor units 6A, 6B perform heating operation and a small number of indoor units 6C perform cooling operation.

[0025] The outdoor unit 5 includes a compressor 2 that compresses and discharges the sucked refrigerant, an oil separator 11 provided on the discharge side of the compressor 2, at least three switching valves 12A, 12B, and 12C that switch the circulation path of the refrigerant circulating between the outdoor unit 5 and the indoor units 6A, 6B, and so on, two outdoor heat exchangers 13 that exchange heat between the refrigerant and outside air, two outdoor expansion valves 15 that reduce the pressure of the refrigerant flowing from the indoor units 6A, 6B, and so on to the respective outdoor heat exchangers 13, and an accumulator 16 provided on the suction side of the compressor 2. The outdoor unit 5 also includes an outdoor fan 17 that circulates the outside air that is heat exchanged in the two outdoor heat exchangers 13. The outdoor unit 5 also includes an inverter circuit 18 that controls the operating frequency of the compressor 2, and a control unit 19 that controls the inverter circuit 18.

[0026] The multiple indoor units 6A, 6B, ... all have the same configuration. Below, a representative indoor unit 6A will be described. The indoor unit 6A is equipped with an indoor heat exchanger 21A that exchanges heat between the refrigerant and the indoor air, and an indoor expansion valve 22A that reduces the pressure of the refrigerant flowing from the outdoor unit 5 into the indoor heat exchanger 21A. The indoor unit 6A also has an indoor fan 23A that circulates the indoor air that has been heat exchanged in the indoor heat exchanger 21A. The indoor unit 6A also has an indoor control unit (not shown).

[0027] The multiple switching units 7A, 7B, ... all have the same configuration. A representative switching unit 7A will be described below. The switching unit 7A includes a discharge gas pipe shutoff valve 25A that allows or blocks the flow of refrigerant from the compressor 2 to the indoor heat exchanger 21A, and a suction gas pipe shutoff valve 26A that allows or blocks the flow of refrigerant from the indoor heat exchanger 21A to the compressor 2. By closing the discharge gas pipe shutoff valve 25A and opening the suction gas pipe shutoff valve 26A, the indoor heat exchanger 21A of the indoor unit 6A functions as an evaporator. By opening the discharge gas pipe shutoff valve 25A and closing the suction gas pipe shutoff valve 26A, the indoor heat exchanger 21A functions as a condenser.

[0028] The compressor 2 is housed in the outdoor unit 5. The compressor 2 changes its operating frequency depending on the output of the inverter circuit 18. The air conditioning apparatus 1 may be equipped with multiple compressors 2. In this case, it is preferable that the number of inverter circuits 18 is the same as the number of compressors 2, and each inverter circuit 18 individually controls the operating frequency of the corresponding compressor 2. The compressors 2 change their operating frequency using known inverter control. The compressors 2 may also be operated at a constant operating frequency.

[0029] The compressor 2 includes a sealed case, a compression mechanism that compresses the refrigerant, and an electric motor that drives the compression mechanism. The sealed case houses the compression mechanism and the electric motor. The sealed case stores refrigeration oil that lubricates the compression mechanism. The discharge side of the compressor 2 is connected to an oil separator 11. The suction side of the compressor 2 is connected to an accumulator 16. The compressor 2 also includes an accumulator 2a with a smaller capacity than the accumulator 16. This small-capacity accumulator 2a is a gas-liquid separator that separates gas refrigerant and liquid refrigerant and sends the gas refrigerant to the compressor 2. The small-capacity accumulator 2a is also called a suction muffler or suction cup, and is provided between the suction side of the compressor 2 and the large-capacity accumulator 16.

[0030] The oil separator 11 separates the gas refrigerant discharged from the compressor 2 from the refrigerating machine oil. The refrigerating machine oil separated by the oil separator 11 is returned to the compressor 2 through a return pipe (not shown). The oil separator 11 is, for example, a centrifugal separator.

[0031] Each of the outdoor heat exchangers 13 and the indoor heat exchangers 21A is, for example, a fin-and-tube heat exchanger. Each of the outdoor heat exchangers 13 and the indoor heat exchangers 21A includes a plurality of paths 28 through which a refrigerant flows, a header 29 that distributes the refrigerant to the paths 28 or joins the refrigerant distributed to the paths 28, and a plurality of fins that extend perpendicular to the paths 28.

[0032] The two outdoor heat exchangers 13 include a main heat exchanger 31 a serving as a first outdoor heat exchanger and a sub-heat exchanger 31 b serving as a second outdoor heat exchanger connected in parallel to the main heat exchanger 31 a. The main heat exchanger 31 a is connected to the first selector valve 12A. The sub-heat exchanger 31 b is connected to the second selector valve 12B.

[0033] Each of the switching valves 12A, 12B, and 12C is electrically connected to the control unit 19 via a signal line (not shown). The air conditioning apparatus 1 switches between cooling operation (refrigerant flow indicated by solid arrows in FIG. 1 ) and heating operation (refrigerant flow indicated by dashed arrows in FIG. 1 ) by switching the refrigerant flow direction using the three switching valves 12A, 12B, and 12C.

[0034] The first switching valve 12A connects the discharge side of the compressor 2 to the main heat exchanger 31a to cause the main heat exchanger 31a to function as a condenser. Also, the first switching valve 12A connects the suction side of the compressor 2 to the main heat exchanger 31a to cause the main heat exchanger 31a to function as an evaporator.

[0035] The second switching valve 12B connects the discharge side of the compressor 2 to the auxiliary heat exchanger 31b to cause the auxiliary heat exchanger 31b to function as a condenser. The second switching valve 12B also connects the suction side of the compressor 2 to the auxiliary heat exchanger 31b to cause the auxiliary heat exchanger 31b to function as an evaporator.

[0036] The third switching valve 12C cuts off the connection between the discharge side of the compressor 2 and the indoor heat exchangers 21A, 21B, ... of all indoor units 6A, 6B, ..., allowing the two outdoor heat exchangers 13 to function as condensers, or connects the discharge side of the compressor 2 to the indoor heat exchanger 21A, 21B, ... of at least one indoor unit 6A, 6B, ..., allowing the indoor heat exchanger 21A, 21B, ... of at least one indoor unit 6A, 6B, ... to function as a condenser.

[0037] The two outdoor expansion valves 15 are a first outdoor expansion valve 15a connected to the main heat exchanger 31a and a second outdoor expansion valve 15b connected to the auxiliary heat exchanger 31b.

[0038] The main heat exchanger 31a is disposed between the first switching valve 12A and the first outdoor expansion valve 15a, and the auxiliary heat exchanger 31b is disposed between the second switching valve 12B and the second outdoor expansion valve 15b. In other words, the refrigerant is distributed at the inlet sides of the main heat exchanger 31a and the auxiliary heat exchanger 31b and merges at the outlet sides of the main heat exchanger 31a and the auxiliary heat exchanger 31b.

[0039] The outdoor fan 17 and the indoor fan 23A are, for example, axial fans. The outdoor fan 17 promotes heat exchange between the outside air and the refrigerant flowing through the two outdoor heat exchangers 13. The indoor fan 23A promotes heat exchange between the indoor air and the refrigerant flowing through the indoor heat exchanger 21A.

[0040] The two outdoor expansion valves 15 and the indoor expansion valve 22A are, for example, electronic expansion valves (Pulse Motor Valves, PMVs) with adjustable valve opening. The electronic expansion valve has a valve body with a through hole and a needle as a valve body that can move forward and backward relative to the through hole. When the needle blocks the through hole, the electronic expansion valve blocks the flow of refrigerant. At this time, the electronic expansion valve is in a closed state, and the valve opening of the electronic expansion valve is smallest. When the needle is farthest from the through hole, the electronic expansion valve maximizes the flow rate of refrigerant. At this time, the electronic expansion valve is in a fully open state, and the valve opening of the electronic expansion valve is largest.

[0041] The accumulator 16 is a gas-liquid separator that separates the gas refrigerant from the liquid refrigerant and sends the gas refrigerant to the compressor 2.

[0042] The discharge gas pipe shutoff valve 25A and the suction gas pipe shutoff valve 26A may be on-off valves or electronic expansion valves with adjustable opening. The discharge gas pipe shutoff valve 25A allows or blocks the flow of refrigerant discharged from the compressor 2 and discharged to the indoor heat exchanger 21A through the third switching valve 12C. The suction gas pipe shutoff valve 26A allows or blocks the flow of refrigerant drawn from the indoor heat exchanger 21A to the compressor 2.

[0043] The refrigerant piping 8 includes three transfer pipes 35, 36, 37 that connect the outdoor unit 5 to the multiple switching units 7A, 7B, ... and allow the refrigerant to flow back and forth, and two transfer pipes 38A, 39A that connect the switching unit 7A to the indoor unit 6A and allow the refrigerant to flow back and forth. The transfer pipes 35, 36, 37 are branch pipes that connect one outdoor unit 5 to the multiple switching units 7A, 7B, ....

[0044] The outdoor unit 5 includes a pipe connection portion 41 to which the connecting pipe 35 is connected, a pipe connection portion 42 to which the connecting pipe 36 is connected, and a pipe connection portion 43 to which the connecting pipe 37 is connected.

[0045] The switching unit 7A includes a pipe connection portion 45A for connecting the connecting pipe 35, a pipe connection portion 46A for connecting the connecting pipe 36, and a pipe connection portion 47A for connecting the connecting pipe 37.

[0046] The jumper pipe 35 is a branch pipe that connects one pipe connection portion 41 to multiple pipe connections 45A, 45B, etc. The jumper pipe 36 is a branch pipe that connects one pipe connection portion 42 to multiple pipe connections 46A, 46B, etc. The jumper pipe 37 is a branch pipe that connects one pipe connection portion 43 to multiple pipe connections 47A, 47B, etc.

[0047] The switching unit 7A also includes a pipe connection portion 48A to which the connecting pipe 38A is connected, and a pipe connection portion 49A to which the connecting pipe 39A is connected.

[0048] The indoor unit 6A includes a pipe connection portion 51A to which the connecting pipe 38A is connected, and a pipe connection portion 52A to which the connecting pipe 39A is connected.

[0049] The pipe connections 41, 42, 43 of the outdoor unit 5, the pipe connections 45A, 45B, 45C, 46A, 46B, 46C, 47A, 47B, 47C on the outdoor unit 5 side of each of the switching units 7A, 7B, ..., the pipe connections 48A, 48B, 48C, 49A, 49B, 49C on the indoor unit 6A, 6B side of each of the switching units 7A, 7B, ..., and the pipe connections 51A, 51B, 51C, 52A, 52B, 52C of the indoor units 6A, 6B, ... are packed valves (back seating type valves) having a structure that prevents refrigerant from being released into the atmosphere.

[0050] The refrigerant piping 8 sequentially connects the compressor 2, the oil separator 11, three switching valves 12A, 12B, 12C, two outdoor heat exchangers 13, two outdoor expansion valves 15, a plurality of indoor expansion valves 22A, 22B, ..., a plurality of indoor heat exchangers 21A, 21B, ..., a plurality of discharge gas pipe shutoff valves 25A, 25B, ..., a plurality of suction gas pipe shutoff valves 26A, 26B, ..., and the accumulator 16.

[0051] The refrigerant piping 8 in the outdoor unit 5 includes a first piping 61 connecting the discharge side of the compressor 2 and the oil separator 11, a second branch pipe 62 connecting the oil separator 11 and the three switching valves 12A, 12B, and 12C, a third piping 63 connecting the first switching valve 12A and one of the outdoor heat exchangers 13, a fourth piping 64 connecting the second switching valve 12B and the other outdoor heat exchanger 13, a fifth piping 65 connecting one of the outdoor heat exchangers 13 and one of the outdoor expansion valves 15, a sixth piping 66 connecting the other outdoor heat exchanger 13 and the other outdoor expansion valve 15, and a seventh branch pipe 67 connecting the two outdoor expansion valves 15 and the piping connection portion 41.

[0052] The first pipe 61 and the second branch pipe 62 are refrigerant feed pipes that are connected to the discharge side of the compressor 2 regardless of the switching states of the three switching valves 12A, 12B, and 12C.

[0053] In addition, the refrigerant piping 8 in the outdoor unit 5 includes an eighth branch pipe 68 that connects the piping connection part 43, the three switching valves 12A, 12B, 12C, and the accumulator 16, a ninth pipe 69 that connects the accumulator 16 and the suction side of the compressor 2, and a tenth pipe 70 that connects the third switching valve 12C and the piping connection part 42.

[0054] The eighth branch pipe 68 and the ninth pipe 69 are refrigerant return pipes that are connected to the suction side of the compressor 2 regardless of the switching states of the three switching valves 12A, 12B, and 12C.

[0055] The refrigerant piping 8 in each switching unit 7A includes an eleventh piping 71A connecting the piping connection portion 45A and the piping connection portion 48A, a twelfth branch pipe 72A connecting the discharge gas pipe shut-off valve 25A, the suction gas pipe shut-off valve 26A, and the piping connection portion 49A, a thirteenth piping 73A connecting the piping connection portion 46A and the discharge gas pipe shut-off valve 25A, and a fourteenth piping 74A connecting the piping connection portion 47A and the suction gas pipe shut-off valve 26A.

[0056] The refrigerant piping 8 in each indoor unit 6A includes a fifteenth piping 75A connecting the piping connection portion 51A and the indoor expansion valve 22A, a sixteenth piping 76A connecting the indoor expansion valve 22A and the indoor heat exchanger 21A, and a seventeenth piping 77A connecting the indoor heat exchanger 21A and the piping connection portion 52A.

[0057] The inverter circuit 18 rectifies AC power supplied from a commercial AC power source, converts the rectified DC power into a frequency according to a command from the control unit 19, and outputs the DC power to the motor of the compressor 2. In other words, the inverter circuit 18 can control the operating frequency of the compressor 2.

[0058] The control unit 19 controls the inverter circuit 18 to control the operating frequency of the compressor 2. The control unit 19 also controls the three switching valves 12A, 12B, 12C, the plurality of discharge gas pipe shutoff valves 25A, 25B, ..., and the plurality of suction gas pipe shutoff valves 26A, 26B, ... based on operating operations input to a remote controller (not shown), and switches between full cooling operation (refrigerant flow indicated by solid arrows in FIG. 1) and full heating operation (refrigerant flow indicated by dashed arrows in FIG. 1) of the air conditioner 1. The control unit 19 may be distributed between the outdoor unit 5 and the indoor units 6A, 6B, ... For example, the control unit 19 of the outdoor unit 5 controls the inverter circuit 18 and the three switching valves 12A, 12B, 12C, and the control unit 19 of each indoor unit 6A, 6B, ... controls the corresponding discharge gas pipe shutoff valves 25A, 25B, ... and suction gas pipe shutoff valves 26A, 26B, ....

[0059] Here, we will explain the operating states of the air conditioning apparatus 1. In either operating state, the compressor 2 discharges refrigerant to the first pipe 61 and the second branch pipe 62, and draws refrigerant from the eighth branch pipe 68 and the ninth pipe 69.

[0060] The refrigerant flow direction during full cooling operation is indicated by solid arrows in Figure 1. The first and second switching valves 12A and 12B are switched to connect the discharge side of the compressor 2 to the respective outdoor heat exchangers 13 (31a, 31b). That is, the second branch pipe 62 is connected to the third pipe 63 and the fourth pipe 64. The third switching valve 12C is switched to disconnect the discharge side of the compressor 2 from the tenth pipe 70. The discharge gas pipe shutoff valves 25A, 25B, etc. are fully closed. The suction gas pipe shutoff valves 26A, 26B, etc. are fully opened to connect the indoor heat exchangers 21A, 21B, etc. to the suction side of the compressor 2.

[0061] The compressor 2 discharges high-temperature, high-pressure gas refrigerant to the first pipe 61. The high-temperature, high-pressure gas refrigerant flows from the first pipe 61 into the oil separator 11. The oil separator 11 separates refrigeration oil from the high-temperature, high-pressure gas refrigerant. The gas refrigerant from which the oil has been separated flows out of the oil separator 11, passes through the first switching valve 12A and the second switching valve 12B, and reaches the two outdoor heat exchangers 13 (31a, 31b). The two outdoor heat exchangers 13 (31a, 31b) exchange heat between the gas refrigerant and outside air, condenses the refrigerant, and causes the liquid refrigerant to flow out. The liquid refrigerant flowing out of the two outdoor heat exchangers 13 (31a, 31b) passes through two outdoor expansion valves 15 (15a, 15b), eleventh pipes 71A, 71B, etc. in the respective switching units 7A, 7B, etc., and the respective indoor expansion valves 22A, 22B, etc., before reaching the respective indoor heat exchangers 21A, 21B, etc. The two outdoor expansion valves 15 (15a, 15b) adjust the flow rate of the liquid refrigerant to adjust the degree of subcooling. The respective indoor expansion valves 22A, 22B, etc., reduce the pressure of the liquid refrigerant to form low-pressure two-phase gas-liquid refrigerant. The respective indoor heat exchangers 21A, 21B, etc., exchange heat between the indoor air and the two-phase gas-liquid refrigerant, evaporating the refrigerant and causing the gas refrigerant to flow out. The gas refrigerant flowing out from each indoor heat exchanger 21A, 21B, ... is sent back to the outdoor unit 5 through the suction gas pipe shutoff valves 26A, 26B, ... of each switching unit 7A, 7B, .... At this time, the discharge gas pipe shutoff valves 25A, 25B, ... are fully closed, and the flow of refrigerant in the crossover pipe 36 is obstructed. The gas refrigerant that has reached the outdoor unit 5 is sucked into the accumulator 16 through the eighth branch pipe 68. The accumulator 16 separates a small amount of liquid refrigerant mixed in with the gas refrigerant. The gas refrigerant from which the liquid portion has been separated flows out of the accumulator 16 and is sucked into the compressor 2. The sucked gas refrigerant is compressed by the compressor 2 and discharged from the compressor 2 again.

[0062] Next, the refrigerant flow direction during heating only operation is indicated by dashed arrows in Figure 1. The refrigerant flows generally in the opposite direction to that during cooling only operation. The third switching valve 12C is switched to connect the discharge side of the compressor 2 to the switching units 7A, 7B, etc. In other words, the second branch pipe 62 is connected to the tenth piping 70. The discharge gas pipe shutoff valves 25A, 25B, etc. are fully opened to connect the discharge side of the compressor 2 to the indoor heat exchangers 21A, 21B, etc. The suction gas pipe shutoff valves 26A, 26B, etc. are fully closed. The first switching valve 12A and the second switching valve 12B are switched to connect the two outdoor heat exchangers 13 (31a, 31b) to the suction side of the compressor 2.

[0063] The gas refrigerant from which the oil has been separated flows out of the oil separator 11 and passes through the third switching valve 12C to reach the respective switching units 7A, 7B, etc. The gas refrigerant that has reached the respective switching units 7A, 7B, etc. reaches the respective indoor heat exchangers 21A, 21B, etc. through the respective discharge gas pipe shutoff valves 25A, 25B, etc. At this time, the suction gas pipe shutoff valves 26A, 26B, etc. are fully closed. The indoor heat exchangers 21A, 21B, etc. exchange heat between the gas refrigerant and the indoor air, condensing the refrigerant and causing the liquid refrigerant to flow out. The liquid refrigerant flowing out of the indoor heat exchangers 21A, 21B, etc. passes through the respective indoor expansion valves 22A, 22B, etc., the eleventh pipes 71A, 71B, etc. in the respective switching units 7A, 7B, etc., and the two outdoor expansion valves 15 (15a, 15b) to reach the two outdoor heat exchangers 13 (31a, 31b). The two outdoor expansion valves 15 (15a, 15b) reduce the pressure of the liquid refrigerant to form a low-pressure gas-liquid two-phase refrigerant. The two outdoor heat exchangers 13 (31a, 31b) exchange heat between outside air and the gas-liquid two-phase refrigerant to evaporate the refrigerant and discharge the gas refrigerant. The gas refrigerant discharged from the two outdoor heat exchangers 13 (31a, 31b) is drawn into the accumulator 16 through the first switching valve 12A and the second switching valve 12B.

[0064] FIG. 2 is a diagram showing a first example of the flow of refrigerant in a cooling and mixed operation state of the air conditioner according to this embodiment.

[0065] 2 illustrates a case in which the two outdoor heat exchangers 13 (31a, 31b) function as condensers, and the indoor heat exchangers 21A, 21B function as evaporators during cooling operation, while the indoor heat exchanger 21C functions as a condenser during heating operation. The direction of refrigerant flow during cooling operation is indicated by solid arrows in FIG. 2, and the direction of refrigerant flow during heating operation is indicated by dashed arrows in FIG. 2.

[0066] The control unit 19 controls the three switching valves 12A, 12B, 12C, the multiple discharge gas pipe shut-off valves 25A, 25B, ..., and the multiple suction gas pipe shut-off valves 26A, 26B, ... based on operating operations input to a remote controller (not shown), and performs the first example of cooling mixed operation of the air conditioning device 1.

[0067] In the case of the cooling mixed operation of the first example, the first switching valve 12A and the second switching valve 12B are switched to connect the discharge side of the compressor 2 to the two outdoor heat exchangers 13 (31a, 31b). The third switching valve 12C is switched to connect the discharge side of the compressor 2 to the switching units 7A, 7B, .... In other words, the discharge side of the compressor 2 is connected to the two outdoor heat exchangers 13 (31a, 31b) and is also connected to the switching units 7A, 7B, ....

[0068] In the first example of mixed cooling operation, the switching state of the third switching valve 12C is different from that in the case of full cooling operation, and the open / closed states of the discharge gas pipe shut-off valve 25C and the suction gas pipe shut-off valve 26C connected to the indoor heat exchanger 21C performing heating operation are reversed.

[0069] The discharge gas pipe shutoff valves 25A, 25B connected to the indoor heat exchangers 21A, 21B performing cooling operation are fully closed, and the suction gas pipe shutoff valves 26A, 26B connected to the indoor heat exchangers 21A, 21B performing cooling operation are fully opened. The indoor heat exchangers 21A, 21B are connected to the suction side of the compressor 2.

[0070] In addition, the discharge gas pipe shutoff valve 25C connected to the indoor heat exchanger 21C performing the heating operation is fully opened, and the suction gas pipe shutoff valve 26C connected to the indoor heat exchanger 21C performing the heating operation is fully closed. The indoor heat exchanger 21C is connected to the discharge side of the compressor 2.

[0071] The refrigerant flow during the cooling mixed operation of the first example will be described, focusing on the differences from the refrigerant flow during full cooling operation. A portion of the gas refrigerant from which the oil has been separated flows out of the oil separator 11 and passes through the first and second switching valves 12A and 12B to the two outdoor heat exchangers 13 (31a, 31b). The remainder passes through the third switching valve 12C to the discharge gas pipe shutoff valves 25A, 25B, etc. of the switching units 7A, 7B, etc. The fully closed discharge gas pipe shutoff valves 25A, 25B shut off the flow of refrigerant toward the indoor units 6A, 6B, while the fully open discharge gas pipe shutoff valve 25C allows the flow of refrigerant toward the indoor unit 6C. The indoor heat exchanger 21C exchanges heat between the gas refrigerant and the indoor air, condensing the refrigerant and discharging the liquid refrigerant. The liquid refrigerant flowing out of the indoor heat exchanger 21C passes through the indoor expansion valve 22C and the eleventh pipe 71 in the switching unit 7C, and joins with the refrigerant flowing into the other indoor heat exchangers 21A and 21B through the connecting pipe 35.

[0072] FIG. 3 is a diagram showing a second example of the flow of refrigerant in the cooling and mixed operation state of the air conditioner according to this embodiment.

[0073] 3 illustrates a case where the auxiliary heat exchanger 31b functions as a condenser, and the indoor heat exchangers 21A and 21B function as evaporators during cooling operation, while the indoor heat exchanger 21C functions as a condenser during heating operation. The direction of refrigerant flow during cooling operation is indicated by solid arrows in FIG. 3, and the direction of refrigerant flow during heating operation is indicated by dashed arrows in FIG. 3.

[0074] The control unit 19 controls the three switching valves 12A, 12B, 12C, the multiple discharge gas pipe shut-off valves 25A, 25B, ..., and the multiple suction gas pipe shut-off valves 26A, 26B, ... based on operating operations input to a remote controller (not shown), and performs the second example of cooling mixed operation of the air conditioning device 1.

[0075] In the case of the second example of cooling mixed operation, the first switching valve 12A blocks the main heat exchanger 31a from the discharge side of the compressor 2, and the second switching valve 12B is switched to connect the discharge side of the compressor 2 to the auxiliary heat exchanger 31b.

[0076] The third switching valve 12C is switched to connect the discharge side of the compressor 2 to the plurality of switching units 7A, 7B, .... In other words, the discharge side of the compressor 2 is connected to the auxiliary heat exchanger 31b and also to the switching units 7A, 7B, ....

[0077] In the second example of mixed cooling operation, the switching states of the first switching valve 12A and the third switching valve 12C are different from those in the case of full cooling operation, the open / close state of the first outdoor expansion valve 15a is reversed, and the open / close states of the discharge gas pipe shut-off valve 25C and the suction gas pipe shut-off valve 26C connected to the indoor heat exchanger 21C performing heating operation are reversed.

[0078] The discharge gas pipe shutoff valves 25A, 25B connected to the indoor heat exchangers 21A, 21B performing cooling operation are fully closed, and the suction gas pipe shutoff valve 26C connected to the indoor heat exchangers 21A, 21B performing cooling operation is fully opened. The indoor heat exchangers 21A, 21B are connected to the suction side of the compressor 2.

[0079] In addition, the discharge gas pipe shutoff valve 25C connected to the indoor heat exchanger 21C performing the heating operation is fully opened, and the suction gas pipe shutoff valve 26C connected to the indoor heat exchanger 21C performing the heating operation is fully closed. The indoor heat exchanger 21C is connected to the discharge side of the compressor 2.

[0080] In the second example of cooling mixed operation, the refrigerant flows in roughly the same way as in the first example of cooling mixed operation, but the first switching valve 12A and the first outdoor expansion valve 15a block the flow of refrigerant to the main heat exchanger 31a.

[0081] The cooling and heating operation of the second example does not require as much refrigeration capacity as the cooling and heating operation of the first example, and is an operation mode that is advantageous when the outside air temperature is close to the target temperature.

[0082] In addition, the outdoor unit 5 of the air conditioning device 1 that does not perform the cooling mixed operation of the second example but performs the cooling mixed operation of the first example only needs to be equipped with at least one outdoor heat exchanger 13 and at least one outdoor expansion valve 15, and does not need to be equipped with the second switching valve 12B connected to the auxiliary heat exchanger 31b.

[0083] FIG. 4 is a diagram showing an example of the flow of refrigerant in the heating and mixed operation state of the air conditioner according to this embodiment.

[0084] 4 illustrates a heating operation in which the two outdoor heat exchangers 13 (31a, 31b) function as evaporators, the indoor heat exchangers 21A, 21B function as condensers, and the indoor heat exchanger 21C functions as an evaporator in a cooling operation. The direction of refrigerant flow during cooling operation is indicated by solid arrows in FIG. 4, and the direction of refrigerant flow during heating operation is indicated by dashed arrows in FIG. 4.

[0085] The control unit 19 controls the three switching valves 12A, 12B, 12C, the multiple discharge gas pipe shut-off valves 25A, 25B, ..., and the multiple suction gas pipe shut-off valves 26A, 26B, ... based on operating operations input to a remote controller (not shown), and performs heating and mixed operation of the air conditioning device 1.

[0086] The switching states of the three changeover valves 12A, 12B, and 12C in the heating mixed operation are the same as the switching states of the three changeover valves 12A, 12B, and 12C in the heating only operation.

[0087] In the heating mixed operation, the open / closed states of the discharge gas pipe shutoff valve 25C and the suction gas pipe shutoff valve 26C connected to the indoor heat exchanger 21C performing the cooling operation are reversed compared to the case of the full heating operation.

[0088] The discharge gas pipe shutoff valves 25A, 25B connected to the indoor heat exchangers 21A, 21B performing heating operation are fully opened, and the suction gas pipe shutoff valves 26A, 26B connected to the indoor heat exchangers 21A, 21B performing heating operation are fully closed. In other words, the indoor heat exchangers 21A, 21B are connected to the discharge side of the compressor 2.

[0089] In addition, the discharge gas pipe shutoff valve 25C connected to the indoor heat exchanger 21C performing cooling operation is fully closed, and the suction gas pipe shutoff valve 26C connected to the indoor heat exchanger 21C performing cooling operation is fully opened. In other words, the indoor heat exchanger 21C is connected to the suction side of the compressor 2.

[0090] In the heating mixed operation, the refrigerant flows in roughly the same way as in the heating only operation, but the liquid refrigerant flowing out of the indoor heat exchangers 21A, 21B branches at the crossover pipe 35, is depressurized by the indoor expansion valve 22C, and reaches the indoor heat exchanger 21C. The indoor heat exchanger 21C exchanges heat between the indoor air and the gas-liquid two-phase refrigerant to evaporate the refrigerant and discharges the gas refrigerant. The gas refrigerant flowing out of the indoor heat exchanger 21C is drawn into the accumulator 16 through the suction gas pipe shutoff valve 26C.

[0091] Next, the outdoor unit 5 will be described in detail.

[0092] FIG. 5 is an exploded perspective view of a first example of an outdoor unit according to an embodiment of the present invention.

[0093] As shown in Fig. 5 , the outdoor unit 5 according to this embodiment includes a housing 81. The housing 81 is a box-shaped rectangular parallelepiped that is long in the vertical direction. The housing 81 includes a rectangular bottom plate 82 in a plan view, four support columns 83 rising from the bottom plate 82, a removable rectangular front plate 85 that covers the front of the housing 81, a rectangular front upper plate 86 that covers the upper part of the front of the housing 81, two rectangular upper side plates 87 that cover the upper parts of the left and right side surfaces of the housing 81, a rectangular lower side plate 88 that covers the front part of the lower right surface of the housing 81, a rectangular rear plate 89 that covers the upper part of the rear surface of the housing 81, and a fan guard 90 that covers the top surface of the housing 81.

[0094] The four support posts 83 extend upward from the vicinity of each of the four corners of the bottom plate 82 .

[0095] Large openings are provided at the bottom of the left and right sides of the housing 81 and at the bottom of the back of the housing 81. These openings are intake ports that draw outside air from the outside to the inside of the outdoor unit 5 by driving the outdoor fan 17. The two outdoor heat exchangers 13 are disposed in these openings.

[0096] The housing 81 houses the compressor 2, the oil separator 11, the three switching valves 12A, 12B, and 12C, the two outdoor heat exchangers 13, the two outdoor expansion valves 15, the accumulator 16, and the refrigerant piping 8 connecting these components. The housing 81 also includes an electric component box 91 that houses the control unit 19.

[0097] The outdoor fan 17 is located at the top of the housing 81. The outdoor fan 17 draws in outside air through an inlet where the two outdoor heat exchangers 13 are located, and exhausts the air through a bellmouth 92. The outdoor fan 17 blows air upward above the outdoor unit 5. The outdoor fan 17 is supported by a fan base 93 that is supported by four supports 83 of the housing 81. The fan base 93 supports the outdoor fan 17 and the bellmouth 92. The bellmouth 92 is an outlet for the outdoor fan 17, and rectifies the post-heat-exchange outside air that flows out from the outdoor fan 17. The bellmouth 92 is surrounded on all four sides (front, back, left, and right) by a front upper plate 86, two side upper plates 87, and a rear plate 89.

[0098] FIG. 6 is a front view of a first example of an outdoor unit according to an embodiment of the present invention.

[0099] FIG. 7 is a schematic front view of a first example of an outdoor unit according to an embodiment of the present invention.

[0100] FIG. 8 is a plan view of a first example of an outdoor unit according to an embodiment of the present invention.

[0101] 6 to 8 show the bottom plate 82 of the outdoor unit 5, the two outdoor heat exchangers 13, the three switching valves 12A, 12B, and 12C, the oil separator 11, the accumulator 16, and the refrigerant piping 8, and omit other major components.

[0102] When the front panel 85, which serves as a detachable side surface, is removed from the housing 81, the interior of the outdoor unit 5 can be viewed directly in the direction of the solid white arrow extending from the front to the back of the housing 81, as shown in Figure 8. In this state, the equipment inside the outdoor unit 5 can be maintained, replaced, or repaired.

[0103] 6 to 8 , one of the outdoor heat exchangers 13 of the outdoor unit 5 according to this embodiment is a main heat exchanger 31a serving as a first outdoor heat exchanger, and the other is a sub-heat exchanger 31b serving as a second outdoor heat exchanger. The main heat exchanger 31a is disposed above the sub-heat exchanger 31b. The main heat exchanger 31a is preferably disposed directly above the sub-heat exchanger 31b.

[0104] The paths 28 of the main heat exchanger 31a and the auxiliary heat exchanger 31b extend horizontally within the housing 81 to allow the refrigerant to circulate. The fins of the main heat exchanger 31a and the auxiliary heat exchanger 31b extend vertically within the housing 81, perpendicular to the paths 28. The main heat exchanger 31a and the auxiliary heat exchanger 31b have end faces 101, 102 that are aligned in a single plane. These end faces 101, 102 face the horizontal direction of the housing 81.

[0105] The fins of the main heat exchanger 31 a and the fins of the sub-heat exchanger 31 b are separated from each other. It is preferable that the end face 101 of the main heat exchanger 31 a and the end face 102 of the sub-heat exchanger 31 b are arranged substantially on a single plane.

[0106] The main heat exchanger 31a and the auxiliary heat exchanger 31b may be an integrated heat exchanger separated by dashed line D in FIG. 6 . For example, the main heat exchanger 31a is the upper half of the integrated heat exchanger, and the auxiliary heat exchanger 31b is the lower half of the integrated heat exchanger. The fins of the main heat exchanger 31a and the fins of the auxiliary heat exchanger 31b are continuous across both heat exchangers 31a and 31b. An integrated heat exchanger including the main heat exchanger 31a and the auxiliary heat exchanger 31b and sharing the fins is more cost-effective to manufacture than the two divided main heat exchangers 31a and 31b. The paths 28 of the main heat exchanger 31a penetrate the upper half of the fins, and the paths 28 of the auxiliary heat exchanger 31b penetrate the lower half of the fins. In this case, the plane on which the end face 101 of the main heat exchanger 31a and the end face 102 of the auxiliary heat exchanger 31b are aligned is a single end face of the integrated heat exchanger. In other words, the end face 101 of the main heat exchanger 31a and the end face 102 of the auxiliary heat exchanger 31b form a single continuous plane. This plane is one of the two main surfaces of the fins located at one end of the integrated heat exchanger, and faces the horizontal direction of the housing 81, just like the end face 101 of the main heat exchanger 31a and the end face 102 of the auxiliary heat exchanger 31b.

[0107] An end face 101 of the main heat exchanger 31a and an end face 102 of the auxiliary heat exchanger 31b face the inner surface of the removable front plate 85. In other words, the end face 101 of the main heat exchanger 31a and the end face 102 of the auxiliary heat exchanger 31b face the front of the housing 81.

[0108] Each of the paths 28 has a refrigerant inlet and a refrigerant outlet that are arranged on an end face 101 of the main heat exchanger 31a or an end face 102 of the auxiliary heat exchanger 31b, which are aligned in a plane. In other words, the inlets and outlets of the multiple paths 28 of the main heat exchanger 31a are arranged on the end face 101 of the main heat exchanger 31a, and the inlets and outlets of the multiple paths 28 of the auxiliary heat exchanger 31b are arranged on the end face 102 of the auxiliary heat exchanger 31b.

[0109] The accumulator 16 and the oil separator 11 are disposed so as to face the inner surface of the exterior heat exchanger 13. The accumulator 16 and the oil separator 11 face the inner surface of the auxiliary heat exchanger 31b located below.

[0110] The three switching valves 12A, 12B, and 12C are disposed above the accumulator 16 and the oil separator 11. The three switching valves 12A, 12B, and 12C are closer to the front of the housing 81 than the accumulator 16 and the oil separator 11.

[0111] The tenth pipe 70 is equipped with a gas valve 105 that shuts off the outflow of refrigerant from the outdoor unit 5 to the outside of the device when the device is shipped from the factory or during installation. The gas valve 105 is a shutoff valve that can be manually opened and closed, and is equipped with an operating part for manual operation. The gas valve 105 is positioned so that the operating part faces the inner surface of the front panel 85. In other words, the gas valve 105 is positioned so that it can be easily opened and closed from the front side of the housing 81 when the front panel 85 is removed from the housing 81.

[0112] FIG. 9 is a perspective view of three switching valves of the outdoor unit according to the embodiment of the present invention.

[0113] 9 indicates the direction from the front to the rear of the housing 81. End faces 101 and 102 of the two heat exchangers 13 are disposed on the right side of the second switching valve 12B when viewed in the direction indicated by the solid arrow.

[0114] 6 to 8, and also as shown in Fig. 9, the first switching valve 12A of the outdoor unit 5 according to this embodiment is closer to the end face 101 of the main heat exchanger 31a than the third switching valve 12C, and the second switching valve 12B is closer to the end face 101 of the main heat exchanger 31a than the first switching valve 12A. In other words, the three switching valves 12A, 12B, and 12C are arranged in the order of the second switching valve 12B, the first switching valve 12A, and the third switching valve 12C from the side closest to the end face 101 of the main heat exchanger 31a.

[0115] Furthermore, the three switching valves 12A, 12B, and 12C are closer to the main heat exchanger 31a than to the auxiliary heat exchanger 31b. That is, the switching valves 12A, 12B, and 12C are arranged in the order of the second switching valve 12B, the first switching valve 12A, and the third switching valve 12C from the side closest to the main heat exchanger 31a.

[0116] The three switching valves 12A, 12B, and 12C are arranged outside a projection area A1 in the normal direction of the end face 101 of the main heat exchanger 31a and the end face 102 of the auxiliary heat exchanger 31b. In other words, the switching valves 12A, 12B, and 12C are arranged outside a projection area A1 in the normal direction of the end face of the outdoor heat exchanger 13. This projection area A1 faces the front of the housing 81.

[0117] The three switching valves 12A, 12B, and 12C are all four-way valves and have the same configuration. The representative first switching valve 12A will be described below.

[0118] The first switching valve 12A includes a valve body 111a, a valve box 112a that accommodates the valve body 111a so that it can be moved horizontally, a first connection port 115a that can be connected to a condenser during cooling operation, a second connection port 116a that can be connected to an evaporator during cooling operation, a third connection port 117a that hangs down below the valve box 112a and is connected to the discharge side of the compressor 2, and a fourth connection port 118a that rises above the valve box 112a and is connected to the suction side of the compressor 2.

[0119] The first switching valve 12A also includes a pilot solenoid valve 119a for operating the valve element 111a. The pilot solenoid valve 119a is connected to the inside of the valve box 112a through a plurality of thin tubes 121a. When the coil (not shown) of the pilot solenoid valve 119a is not energized, the pilot solenoid valve 119a connects the first connection port 115a and the third connection port 117a of the first switching valve 12A and connects the second connection port 116a and the fourth connection port 118a of the first switching valve 12A. When the coil is energized, the pilot solenoid valve 119a connects the first connection port 115a and the fourth connection port 118a of the first switching valve 12A and connects the second connection port 116a and the third connection port 117a of the first switching valve 12A.

[0120] The first connection port 115a, the second connection port 116a, and the fourth connection port 118a are aligned in parallel with each other in the longitudinal direction of the valve body 112a.

[0121] The first connection port 115b of the second switching valve 12B is connected to a fourth pipe 64 continuing to the outdoor heat exchanger 13 (sub-heat exchanger 31b).

[0122] The second connection port 116 b of the second switching valve 12B is closed with a sealing plug 125 .

[0123] The first connection port 115a of the first switching valve 12A is connected to a third pipe 63 continuing to the outdoor heat exchanger 13 (main heat exchanger 31a).

[0124] The second connection port 116 a of the first switching valve 12A is closed by a sealing plug 125 .

[0125] The first connection port 115 c of the third switching valve 12C is closed by a sealing plug 125 .

[0126] The second connection port 116c of the third switching valve 12C is connected to the tenth pipe 70 continuing from the discharge gas pipe shutoff valves 25A, 25B, . . . of the switching units 7A, 7B, .

[0127] The third connection ports 117 a, 117 b, 117 c of the three switching valves 12A, 12B, 12C are connected to a second branch pipe 62 that continues to the discharge side of the compressor 2 via the oil separator 11 .

[0128] The fourth connection ports 118 a, 118 b, 118 c of the three switching valves 12A, 12B, 12C are connected to an eighth branch pipe 68 that continues to the suction side of the compressor 2 via the accumulator 16 .

[0129] The centerlines of the longitudinal cylindrical valve boxes 112a, 112b, and 112c of the switching valves 12A, 12B, and 12C are oriented horizontally. Furthermore, the switching valves 12A, 12B, and 12C are arranged such that the pilot solenoid valves 119a, 119b, and 119c face the inner surface of the detachable front plate 85. In other words, all of the pilot solenoid valves 119a, 119b, and 119c face the inner surface of the front plate 85. In other words, all of the pilot solenoid valves 119a, 119b, and 119c are installed so that their coils can be easily attached and detached with the front plate 85 removed from the housing 81.

[0130] Furthermore, the three switching valves 12A, 12B, and 12C are disposed at substantially the same height position in the housing 81. It is preferable that the difference in height between these switching valves 12A, 12B, and 12C is within the size of each of the switching valves 12A, 12B, and 12C alone before the refrigerant pipe 8 is connected.

[0131] The fourth pipe 64 extending from the second switching valve 12B to the auxiliary heat exchanger 31b is laid so as to hang down within the projection area A1 toward the auxiliary heat exchanger 31b.

[0132] The third pipe 63 extending from the first switching valve 12A to the main heat exchanger 31a is laid across above the second switching valve 12B toward the main heat exchanger 31a.

[0133] The functions of the three switching valves 12A, 12B, and 12C can be fulfilled by three-way valves instead of four-way valves. However, by applying a four-way valve that independently switches between cooling operation and heating operation, as disclosed in Japanese Patent Application Laid-Open No. 2017-180882, to the three switching valves 12A, 12B, and 12C, the three switching valves 12A, 12B, and 12C according to this embodiment can be used in common with four-way valves of different models of air conditioners.

[0134] FIG. 10 is a schematic front view of a first comparative example of the outdoor unit.

[0135] As shown in Figure 10, the outdoor unit 201A of the first comparative example is equipped with three switching valves 12A, 12B, and 12C, arranged in the order of first switching valve 12A, second switching valve 12B, and third switching valve 12C from the side closest to the end face 101 of the main heat exchanger 31a.

[0136] In the first comparative example, the third pipe 63 extending from the first switching valve 12A to the main heat exchanger 31a is laid along the shortest route toward the main heat exchanger 31a.

[0137] However, the fourth pipe 64 extending from the second selector valve 12B to the auxiliary heat exchanger 31b is laid toward the auxiliary heat exchanger 31b, bypassing the area between the second selector valve 12B and the third selector valve 12C and below the second selector valve 12B. The laying path of the fourth pipe 64 in the first comparative example can be said to be a longer route than the laying path of the fourth pipe 64 in the outdoor unit 5 according to the present embodiment.

[0138] The installation route of the refrigerant piping 8 of the outdoor unit 5 according to this embodiment shown in Figure 7 is superior to the installation route of the refrigerant piping 8 of the first comparative example in terms of the total length of the refrigerant piping 8 and the simplicity of the installation route.

[0139] FIG. 11 is a schematic front view of a second comparative example of the outdoor unit.

[0140] As shown in Figure 11, the outdoor unit 201B of the second comparative example has three switching valves 12A, 12B, and 12C arranged in the order of first switching valve 12A, second switching valve 12B, and third switching valve 12C from the side closest to the end face 101 of the main heat exchanger 31a.

[0141] In the second comparative example, the third pipe 63 extending from the first switching valve 12A to the main heat exchanger 31a is laid along the shortest route toward the main heat exchanger 31a.

[0142] However, the fourth pipe 64 extending from the second switching valve 12B to the auxiliary heat exchanger 31b bypasses above the first switching valve 12A and is laid down toward the auxiliary heat exchanger 31b within the projection area A1. The laying path of the fourth pipe 64 in this second comparative example can be said to be a longer route than the laying path of the fourth pipe 64 of the outdoor unit 5 according to this embodiment.

[0143] Furthermore, in the second comparative example, in order to avoid three-dimensional interference with the third pipe 63, the fourth pipe 64, and the header 29 of the main heat exchanger 31a, a certain amount of space is required between the end face 101 of the main heat exchanger 31a and the first switching valve 12A, which is closest to the end face 101 of the main heat exchanger 31a. This certain amount of space increases the width dimension of the outdoor unit 201B, hindering miniaturization of the outdoor unit 201B.

[0144] The installation path of the refrigerant piping 8 of the outdoor unit 5 according to this embodiment shown in Figure 7 is superior to the installation path of the refrigerant piping 8 of the first comparative example in terms of the total length of the refrigerant piping 8, the simplicity of the installation path, and the compactness of the outdoor unit 5.

[0145] Next, a second example of an outdoor unit 5A according to this embodiment will be described.

[0146] FIG. 12 is a front view of a second example of the outdoor unit according to an embodiment of the present invention.

[0147] FIG. 13 is a schematic front view of a second example of the outdoor unit according to an embodiment of the present invention.

[0148] FIG. 14 is a plan view of a second example of the outdoor unit according to an embodiment of the present invention.

[0149] 12 to 14 , the outdoor unit 5A according to this embodiment includes four outdoor heat exchangers 13A. The four outdoor heat exchangers 13A include two main heat exchangers 31a and two auxiliary heat exchangers 31b. The two main heat exchangers 31a are connected in parallel between the first switching valve 12A and the first outdoor expansion valve 15a. The two auxiliary heat exchangers 31b are connected in parallel between the second switching valve 12B and the second outdoor expansion valve 15b.

[0150] The number of second outdoor expansion valves 15b may be the same as the number of auxiliary heat exchangers 31b. In this case, one auxiliary heat exchanger 31b and one second outdoor expansion valve 15b are connected in series, the other auxiliary heat exchanger 31b and the other second outdoor expansion valve 15b are connected in series, and these two series systems are connected in parallel.

[0151] 12 to 14 show the bottom plate 82 of the outdoor unit 5A, the four outdoor heat exchangers 13A, the three switching valves 12A, 12B, and 12C, the oil separator 11, the accumulator 16, and the refrigerant piping 8, and omit other major components.

[0152] When the front panel 85, which serves as a detachable side surface, is removed from the housing 81, the interior of the housing 81 can be viewed directly in the direction of the solid white arrow extending from the front to the rear of the housing 81, as shown in Fig. 14. In this state, the devices inside the outdoor unit 5A can be maintained, replaced, or repaired.

[0153] The four outdoor heat exchangers 13A are substantially symmetrical with respect to a central plane CP that extends in the front-to-rear direction of the housing 81 and divides the housing 81 into left and right halves. The two right-side outdoor heat exchangers 13A extend from one end face 131 located near the right side of the central plane CP of the housing 81 toward the rear face of the housing 81, and extend to the right half of the rear face and the right side of the housing 81. The two left-side outdoor heat exchangers 13A extend from one end face 132 located near the left side of the central plane CP of the housing 81 toward the rear face of the housing 81, and extend to the left half of the rear face and the left side of the housing 81.

[0154] The left and right outdoor heat exchangers 13A have the same configuration. Below, we will explain the representative right outdoor heat exchanger 13A. Furthermore, the same components as the outdoor heat exchanger 13 of the outdoor unit 5 of the first example are given the same reference numerals, and duplicate explanations will be omitted.

[0155] One of the right outdoor heat exchangers 13 is a main heat exchanger 31a serving as a first outdoor heat exchanger, and the other is a sub-heat exchanger 31b serving as a second outdoor heat exchanger. The main heat exchanger 31a is disposed above the sub-heat exchanger 31b. The main heat exchanger 31a is preferably disposed directly above the sub-heat exchanger 31b.

[0156] The end faces 101 of the right and left main heat exchangers 31a are arranged in mirror symmetry, and the end faces 102 of the right and left auxiliary heat exchangers 31b are arranged in mirror symmetry.

[0157] The oil separator 11 is disposed so as to face the inner surface of the left exterior heat exchanger 13. The oil separator 11 faces the inner surface of the left auxiliary heat exchanger 31b.

[0158] The accumulator 16 is disposed so as to face the inner surface of the right exterior heat exchanger 13. The accumulator 16 faces the inner surface of the right auxiliary heat exchanger 31b.

[0159] The three switching valves 12A, 12B, and 12C are arranged on the right side of the housing 81 where the accumulator 16 is arranged, that is, on the right side of the center plane CP.

[0160] In addition, the arrangement of equipment such as the four outdoor heat exchangers 13A, three switching valves 12A, 12B, and 12C, oil separator 11, accumulator 16, and refrigerant piping 8 within the outdoor unit 5A may be reversed left and right with respect to the center plane CP of the housing 81.

[0161] FIG. 15 is a perspective view of three switching valves of the outdoor unit according to the embodiment of the present invention.

[0162] 15 indicates the direction from the front to the rear of the housing 81. End faces 131 and 132 of the two heat exchangers 13A are disposed on the left side of the second switching valve 12B when viewed in the direction indicated by the solid white arrow.

[0163] 12 to 14, and also as shown in Fig. 15, the first switching valve 12A of the outdoor unit 5A according to this embodiment is closer to the end faces 101 of the two main heat exchangers 31a than the third switching valve 12C, and the second switching valve 12B is closer to the end faces 101 of the two main heat exchangers 31a than the first switching valve 12A. In other words, the three switching valves 12A, 12B, and 12C are arranged in the order of the second switching valve 12B, the first switching valve 12A, and the third switching valve 12C, from the side closest to the end faces 101 of the two main heat exchangers 31a.

[0164] Furthermore, the three switching valves 12A, 12B, and 12C are closer to the two main heat exchangers 31a than to the two auxiliary heat exchangers 31b. That is, the switching valves 12A, 12B, and 12C are arranged in the order of the second switching valve 12B, the first switching valve 12A, and the third switching valve 12C from the side closest to the two main heat exchangers 31a.

[0165] The three switching valves 12A, 12B, and 12C are disposed outside a projection area A2 of the housing 81 toward the front, which includes end faces 101 of the two main heat exchangers 31a and end faces 102 of the two auxiliary heat exchangers 31b. In other words, the switching valves 12A, 12B, and 12C are disposed outside the projection area A2 of the end faces of the four outdoor heat exchangers 13.

[0166] The fourth pipe 64 extending from the second switching valve 12B to the two left and right auxiliary heat exchangers 31b is laid so as to hang down within the projected area A toward the auxiliary heat exchangers 31b.

[0167] The third pipe 63 extending from the first switching valve 12A to the two main heat exchangers 31a on the left and right is laid across above the second switching valve 12B toward the main heat exchanger 31a.

[0168] FIG. 16 is a schematic front view of a third comparative example of the outdoor unit.

[0169] As shown in Figure 16, the outdoor unit 201C of the third comparative example has three switching valves 12A, 12B, and 12C arranged in the order of first switching valve 12A, second switching valve 12B, and third switching valve 12C from the side closest to the end faces 101 of the two main heat exchangers 31a.

[0170] In the third comparative example, the third pipe 63 extending from the first switching valve 12A to the two main heat exchangers 31a is laid along the shortest route toward the main heat exchanger 31a.

[0171] However, the fourth piping 64 extending from the second switching valve 12B to the two auxiliary heat exchangers 31 b is laid toward the two auxiliary heat exchangers 31 b, bypassing the left side of the end faces 101 of the two main heat exchangers 31 a. The laying path of the fourth piping 64 in this third comparative example can be said to be a longer route than the laying path of the fourth piping 64 in the outdoor unit 5A according to the present embodiment.

[0172] The installation route of the refrigerant piping 8 of the outdoor unit 5A according to this embodiment shown in Figure 15 is superior to the installation route of the refrigerant piping 8 of the third comparative example in terms of the total length of the refrigerant piping 8 and the simplicity of the installation route.

[0173] FIG. 17 is a schematic front view of a fourth comparative example of the outdoor unit.

[0174] As shown in Figure 17, the outdoor unit 201D of the fourth comparative example has three switching valves 12A, 12B, and 12C arranged in the order of first switching valve 12A, second switching valve 12B, and third switching valve 12C from the side closest to the end face 101 of the two main heat exchangers 31a.

[0175] In the fourth comparative example, the third pipe 63 extending from the first switching valve 12A to the main heat exchanger 31a is laid along the shortest route toward the main heat exchanger 31a.

[0176] However, the fourth piping 64 extending from the second switching valve 12B to the two auxiliary heat exchangers 31b bypasses above the first switching valve 12A and is laid toward the two auxiliary heat exchangers 31b so as to hang down within the projection area A. The laying path of the fourth piping 64 in this fourth comparative example can be said to be a longer route than the laying path of the fourth piping 64 in the outdoor unit 5A according to the present embodiment.

[0177] Furthermore, in the fourth comparative example, in order to avoid three-dimensional interference with the third pipe 63, the fourth pipe 64, and the headers 29 of the two main heat exchangers 31a, a certain amount of space is required between the first switching valve 12A, which is closest to the end faces 101 of the two main heat exchangers 31a, and the end faces 101 of the two main heat exchangers 31a. This certain amount of space increases the width dimension of the outdoor unit 201D, hindering miniaturization of the outdoor unit 201D.

[0178] The installation route of the refrigerant piping 8 of the outdoor unit 5A according to this embodiment shown in Figure 15 is superior to the installation route of the refrigerant piping 8 of the fourth comparative example in terms of the total length of the refrigerant piping 8, the simplicity of the installation route, and the compactness of the outdoor unit 5A.

[0179] FIG. 18 is a block diagram of a second embodiment of an air conditioning apparatus according to an embodiment of the present invention.

[0180] As shown in FIG. 18 , the air conditioning apparatus 1 according to this embodiment does not need to include multiple switching units 7A, 7B, etc. The connecting pipe 35 connects one pipe connection 41 of the outdoor unit 5, 5A to each of the pipe connections 51A, 51B, etc. of the multiple indoor units 6A, 6B, etc. The connecting pipe 36 connects one pipe connection 42 of the outdoor unit 5, 5A to each of the pipe connections 52A, 52B, etc. of the multiple indoor units 6A, 6B, etc. The connecting pipe 37 is not necessary, and the pipe connection 43 is maintained in a closed state. The third switching valve 12C of the outdoor unit 5, 5A switches so that refrigerant is drawn from the multiple indoor units 6A, 6B, etc. into the compressor 2 during cooling operation, and refrigerant is sent from the compressor 2 to the multiple indoor units 6A, 6B, etc. during heating operation.

[0181] The air conditioning apparatus 1 may be provided with a sealing plug 135 that closes the pipe connection portion 43 of the outdoor unit 5, 5A.

[0182] In other words, the air conditioning apparatus 1 can be used in a second configuration in which the piping connection portion 43 is closed, the multiple switching units 7A, 7B, ... and the connecting pipe 37 are not provided, and the outdoor units 5, 5A and the multiple indoor units 6A, 6B, ... are directly connected by connecting pipes 35, 36. The air conditioning apparatus 1 of the second configuration performs cooling operation by circulating the refrigerant in the direction indicated by the solid arrow in Fig. 18, and performs heating operation by circulating the refrigerant in the direction indicated by the dashed arrow in Fig. 18.

[0183] Therefore, when the pipe connection parts 43 of the outdoor units 5, 5A are blocked, the air conditioner 1 functions as a multi-type air conditioner that performs only cooling operation or only heating operation.

[0184] The eighth branch pipe 68, which is not connected to the connecting pipe 37, connects the third switching valve 12C to the accumulator 16 located on the suction side of the compressor 2 and also connects the pipe connection 43 to the accumulator 16. The eighth branch pipe 68 has a branch where three pipes leading to the third switching valve 12C, the accumulator 16, and the pipe connection 43 intersect. In the air conditioner 1 of the second embodiment, the pipe between this branch and the pipe connection 43 becomes a so-called dead end. This dead end may result in refrigerant and refrigeration oil mixed therein accumulating. To recover the refrigerant and refrigeration oil accumulating in the dead end of the eighth branch pipe 68 and return them to the compressor 2, the air conditioner 1 may include a recovery pipe 136, indicated by a two-dot chain line, connecting the pipe connection 43 to the suction side of the accumulator 16.

[0185] As described above, the outdoor unit 5, 5A of the air conditioning apparatus 1 according to this embodiment is equipped with the first selector valve 12A that is closer to the end face 101 of the main heat exchanger 31a than the third selector valve 12C, and the second selector valve 12B that is closer to the end face 101 of the main heat exchanger 31a than the first selector valve 12A. Therefore, the outdoor unit 5, 5A is excellent in terms of the total length of the refrigerant piping 8, the simplicity of the installation path, and the size of the outdoor unit 5.

[0186] Furthermore, the outdoor unit 5, 5A of the air conditioning apparatus 1 according to this embodiment is equipped with three switching valves 12A, 12B, 12C that are arranged outside the projected areas A1, A2 of the end faces of the multiple outdoor heat exchangers 13, 13A, which includes the projected area of ​​the end face 101 of the main heat exchanger 31a. Therefore, the outdoor unit 5, 5A makes it easy to see and approach the paths 28 of the multiple outdoor heat exchangers 13, 13A, and provides excellent workability for the paths 28.

[0187] Furthermore, the outdoor unit 5, 5A of the air conditioning apparatus 1 according to this embodiment may be equipped with a heat exchanger that integrates the main heat exchanger 31a and the auxiliary heat exchanger 31b. In this heat exchanger, the end face 101 of the main heat exchanger 31a and the end face 102 of the auxiliary heat exchanger 31b form a single continuous flat surface. Therefore, the outdoor unit 5, 5A makes the paths 28 of the multiple outdoor heat exchangers 13, 13A easier to see and access, and provides superior workability for the paths 28.

[0188] Furthermore, the outdoor units 5, 5A of the air conditioning apparatus 1 according to this embodiment are equipped with three four-way valves as the three changeover valves 12A, 12B, 12C. By appropriately closing and utilizing the connection ports of these four-way valves, the three changeover valves 12A, 12B, 12C according to this embodiment can be used in common with four-way valves of air conditioning apparatuses of different models.

[0189] Furthermore, the outdoor unit 5, 5A of the air conditioning apparatus 1 according to this embodiment is equipped with three changeover valves 12A, 12B, 12C, each of which has three four-way valves: valve boxes 112a, 112b, 112c that accommodate valve bodies 111a, 111b, 111c so that they can be moved horizontally; third connection ports 117a, 117b, 117c that hang down from the valve boxes 112a, 112b, 112c and are connected to the discharge side of the compressor 2; and fourth connection ports 118a, 118b, 118c that rise up from the valve boxes 112a, 112b, 112c and are connected to the suction side of the compressor 2. Therefore, the outdoor unit 5, 5A is excellent in terms of the total length of the refrigerant piping 8 between the compressor 2 and the three changeover valves 12A, 12B, 12C, the simplicity of the installation path, and the compactness of the outdoor unit 5.

[0190] Furthermore, the outdoor unit 5, 5A of the air conditioning apparatus 1 according to this embodiment is provided with a housing 81 having a detachable front panel 85. The three switching valves 12A, 12B, 12C are provided with pilot solenoid valves 119a, 119b, 119c that face the inner surface of the front panel 85. Therefore, the outdoor unit 5, 5A makes it easy to visually observe and approach the coils attached to the pilot solenoid valves 119a, 119b, 119c of the three switching valves 12A, 12B, 12C, and provides excellent workability for the coils.

[0191] Furthermore, the outdoor unit 5, 5A of the air conditioning apparatus 1 according to this embodiment is equipped with three switching valves 12A, 12B, 12C that are arranged above the accumulator 16. In other words, when the outdoor unit 5, 5A is installed, the three switching valves 12A, 12B, 12C can be arranged at a height of several tens of centimeters from the installation surface of the outdoor unit 5, 5A. Therefore, the three switching valves 12A, 12B, 12C of the outdoor unit 5, 5A are arranged at a height that is easier to work with than if they were closer to the bottom plate 82 of the housing 81.

[0192] The air conditioning apparatus 1 according to this embodiment includes an outdoor unit 5, 5A, multiple indoor units 6A, 6B, and multiple switching units 7A, 7B. The air conditioning apparatus 1 including multiple switching units 7A, 7B can have a mixture of indoor units 6A, 6B, and 6A, 6B operating in cooling mode and indoor units 6A, 6B, and ... 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6A, 6B, 6 In other words, the air conditioning device 1 can function as a heat recovery multi-type air conditioning device by selecting multiple switching units 7A, 7B, ..., and can function as a multi-type air conditioning device by selecting not to apply multiple switching units 7A, 7B, ....

[0193] Therefore, according to the outdoor units 5, 5A of the air conditioning apparatus 1 and the air conditioning apparatus 1 of this embodiment, it is possible to switch the connection between the multiple outdoor heat exchangers 13, 13A, the discharge side of the compressor 2, and the suction side of the compressor 2, and the installation route of the refrigerant piping 8 is excellent.

[0194] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims.

[0195] REFERENCE SIGNS LIST 1...air conditioning apparatus, 2...compressor, 2a...accumulator, 5, 5A...outdoor unit, 6A, 6B, 6C...indoor unit, 7A, 7B, 7C...switching unit, 8...refrigerant piping, 11...oil separator, 12A...first switching valve, 12B...second switching valve, 12C...third switching valve, 13, 13A...outdoor heat exchanger, 15, 15a, 15b...outdoor expansion valve, 16...accumulator, 17...outdoor fan, 18...inverter circuit, 19...control unit, 21A, 21B, 21C...indoor heat exchanger, 22A, 22B, 22C...indoor expansion valve, 23A, 23B, 23C...indoor fan, 2 5A, 25B, 25C...Discharge gas pipe shutoff valve, 26A, 26B, 26C...Suction gas pipe shutoff valve, 28...Path, 29...Header, 31a...Main heat exchanger, 31b...Sub-heat exchanger, 35, 36, 37, 38A, 38B, 38C, 39A, 39B, 39C...Cross-over pipe, 41, 42, 43...Pipe connection part of outdoor unit, 45A, 45B, 45C, 46A, 46B, 46C, 47A, 47B, 47C...Pipe connection part of outdoor unit side of switching unit, 48A, 48B, 48C, 49A, 49B, 49C...Pipe connection part of indoor unit side of switching unit, 51A, 51B, 51C, 5 2A, 52B, 52C...piping connection part of indoor unit, 61...first pipe, 62...second branch pipe, 63...third pipe, 64...fourth pipe, 65...fifth pipe, 66...sixth pipe, 67...seventh branch pipe, 68...eighth branch pipe, 69...ninth pipe, 70...tenth pipe, 71...eleventh pipe, 72A, 72B, 72C...twelfth branch pipe, 73A, 73B, 73C...thirteenth pipe, 74A, 74B, 74C...fourteenth pipe, 75A, 75B, 75C...fifteenth pipe, 76A, 76B, 76C...sixteenth pipe, 77A, 77B, 77C...seventeenth pipe, 81...casing, 82...bottom plate, 83...support, 85...front surface Plate, 86...front upper plate, 87...side upper plate, 88...side lower plate, 89...rear plate, 90...fan guard, 91...electrical component box, 92...bell mouth, 93...fan stand, 101, 102...end surface of heat exchanger, 105...gas valve, 111a, 111b, 111c...valve body, 112a, 112b, 112c...valve box, 115a, 115b, 115c...first connection port, 116a, 116b, 116c...second connection port, 117a, 117b, 117c...third connection port, 118a, 118b, 118c...fourth connection port, 119a, 119b, 119c...pilot solenoid valve, 121a, 121b,121c... thin tube, 125... sealing plug, 131, 132... end surface of heat exchanger, 135... sealing plug, 136... recovery pipe, 201A, 201B, 201C, 201D... outdoor unit comparative example.

Claims

1. a compressor that compresses a refrigerant; a first outdoor heat exchanger that exchanges heat between the refrigerant and outside air; a first switching valve that connects a discharge side of the compressor to the outdoor first heat exchanger to cause the outdoor first heat exchanger to function as a condenser, or that connects a suction side of the compressor to the outdoor first heat exchanger to cause the outdoor first heat exchanger to function as an evaporator; an outdoor second heat exchanger that exchanges heat between the refrigerant and outside air; a second switching valve that connects a discharge side of the compressor to the outdoor second heat exchanger to cause the outdoor second heat exchanger to function as a condenser, or that connects a suction side of the compressor to the outdoor second heat exchanger to cause the outdoor second heat exchanger to function as an evaporator; a third switching valve that can cut off the connection between the discharge side of the compressor and the indoor heat exchangers of all indoor units to cause the outdoor first heat exchanger and the outdoor second heat exchanger to function as condensers, or that can connect the discharge side of the compressor to the indoor heat exchanger of at least one of the indoor units to cause the indoor heat exchanger of the at least one indoor unit to function as a condenser, the first switching valve is closer to the first heat exchanger than the third switching valve; The second switching valve is an outdoor unit of the air conditioner that is closer to the first heat exchanger than the first switching valve.

2. The outdoor unit for an air conditioner according to claim 1 , wherein the first switching valve, the second switching valve, and the third switching valve are arranged outside a projected area in a normal direction of the end face.

3. The outdoor unit of the air conditioning apparatus of claim 2, wherein the first outdoor heat exchanger and the second outdoor heat exchanger are integral, and the end face of the first outdoor heat exchanger and the end face of the second outdoor heat exchanger are one continuous plane.

4. the first switching valve, the second switching valve, and the third switching valve are four-way valves, each having a first connection port connectable to a condenser and a second connection port connectable to an evaporator; The outdoor unit for an air conditioner according to claim 3 , wherein one of the first connection port and the second connection port is blocked.

5. a housing that accommodates the compressor, the outdoor first heat exchanger, the outdoor second heat exchanger, the first switching valve, the second switching valve, and the third switching valve; the end surface of the outdoor first heat exchanger and the end surface of the outdoor second heat exchanger face in a horizontal direction of the housing, The outdoor unit of the air conditioning apparatus described in claim 4, wherein each of the first switching valve, the second switching valve, and the third switching valve comprises a valve body, a valve box that accommodates the valve body so that it can be moved horizontally, a third connection port that hangs down from the valve box and is connected to the discharge side of the compressor, and a fourth connection port that rises up from the valve box and is connected to the suction side of the compressor.

6. the housing has a detachable side surface; The outdoor unit of the air conditioner according to claim 5 , wherein the first switching valve, the second switching valve, and the third switching valve each include a pilot solenoid valve facing the inner surface of the side surface.

7. an accumulator connected to the suction side of the compressor; the first heat exchanger is disposed above the second heat exchanger, The outdoor unit for an air conditioner according to any one of claims 1 to 6, wherein the first switching valve, the second switching valve, and the third switching valve are disposed above the accumulator.

8. An outdoor unit according to any one of claims 1 to 6; A plurality of the indoor units; a plurality of switching units capable of switching the flow direction of the refrigerant flowing to the corresponding indoor units; the indoor unit has an outdoor expansion valve connected to a discharge side of the first heat exchanger, Each of the indoor units has an outdoor heat exchanger and an indoor expansion valve connected to the outdoor heat exchanger, An air conditioner capable of mixing indoor units that perform cooling operation and indoor units that perform heating operation by making the flow directions of the refrigerant flowing through the indoor units different from each other.

9. An outdoor unit according to any one of claims 1 to 6; A plurality of the indoor units, the indoor unit has an outdoor expansion valve connected to a discharge side of the first heat exchanger, Each of the indoor units has an outdoor heat exchanger and an indoor expansion valve connected to the outdoor heat exchanger, An air conditioning apparatus in which one of the branches of the third switching valve is blocked so that the refrigerant is sucked into the compressor through the third switching valve during cooling operation, and the refrigerant is sent to the multiple indoor units through the third switching valve during heating operation.

10. An outdoor unit according to any one of claims 1 to 6; A plurality of the indoor units, the indoor unit has an outdoor expansion valve connected to a discharge side of the first heat exchanger, Each of the indoor units has an outdoor heat exchanger and an indoor expansion valve connected to the outdoor heat exchanger, When a plurality of switching units capable of switching the flow direction of the refrigerant flowing through the corresponding indoor units are provided, the flow directions of the refrigerant flowing through the plurality of indoor units can be made different from each other, and the indoor units performing cooling operation and the indoor units performing heating operation can be mixed, When the plurality of switching units are not provided, one of the branches of the third switching valve is blocked so that the refrigerant is sucked into the compressor through the third switching valve during cooling operation, and the refrigerant is sent to the plurality of indoor units through the third switching valve during heating operation, thereby unifying the flow direction of the refrigerant flowing to the plurality of indoor units and operating all of the indoor units in cooling operation or heating operation.