JP2012036933A - Refrigerant passage switching valve, and air conditioning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerant passage switching valve that can switch the passage of a refrigerant by a relatively simple structure, and to provide an air conditioning device with the refrigerant passage switching valve.SOLUTION: The refrigerant passage switching valve (60) includes: a drive mechanism (70) having an output shaft (74); a case (80) connected with first to sixth ports (91 to 96); and a switching mechanism (100) which switches communication states of the respective ports (91 to 96) by being accommodated in the case (80) and rotationally driven by the output shaft (74). The switching mechanism (100) is displaced to a first angle position which makes the second port (92) and the third port (93) communicate with each other, and also makes the fourth port (94) and the fifth port (95) communicate with each other, a second angel position which makes the first port (91) and the second port (92) communicate with each other, and also makes the fourth port (94) and the fifth port (95) communicate with each other, and a third angle position which makes the first port (91) and the second port (92) communicate with each other, and also makes the fourth port (94) and the sixth port (96) communicate with each other.

Description

  The present invention relates to a refrigerant flow path switching valve that switches a flow path of a refrigerant in a refrigerant circuit, and an air conditioner including the refrigerant flow path switching valve.

  Conventionally, an air conditioner including a refrigerant circuit in which a refrigeration cycle is performed is known. For example, Patent Document 1 discloses this type of air conditioner.

  A compressor, an outdoor heat exchanger, a plurality of indoor expansion valves, a plurality of indoor heat exchangers, and the like are connected to the refrigerant circuit of the air conditioner. The refrigerant circuit is connected to a four-way switching valve and a plurality of electromagnetic valves for switching the refrigerant flow path. In the air conditioner, various operations such as a heating operation and a cooling operation are performed by switching the flow path of the refrigerant.

  In the heating operation, a refrigeration cycle is performed in which each indoor heat exchanger becomes a condenser (radiator) and the outdoor heat exchanger becomes an evaporator. Thereby, in the indoor heat exchanger, the indoor air is heated by the refrigerant. In the cooling operation, a refrigeration cycle is performed in which the outdoor heat exchanger serves as a condenser and each indoor heat exchanger serves as an evaporator. Thereby, in the indoor heat exchanger, the indoor air is cooled by the refrigerant. Furthermore, this air conditioner can be operated to cool the room with at least one indoor heat exchanger and simultaneously heat the room with another indoor heat exchanger by switching the flow path of the refrigerant as the electromagnetic valve opens and closes. The so-called cooling / heating free type is constructed.

JP 2008-133894 A

  By the way, in the air conditioner disclosed in Patent Document 1, the refrigerant is compressed in two stages by two compressors (a low-stage compressor and a high-stage compressor), and the intermediate-pressure refrigerant is intercooled. It is conceivable to perform an operation of cooling in

  Such a refrigerant circuit will be described in detail with reference to FIG. The refrigerant circuit (201) of the air conditioner (200) shown in FIG. 17 represents only the circuit on the outdoor unit side, omitting the circuit on the indoor unit side. A low-stage compressor (202), a high-stage compressor (203), an outdoor heat exchanger (204), an outdoor expansion valve (205), and an intercooler (206) are connected to the refrigerant circuit (201). ing. The low stage compressor (202) and the high stage compressor (203) are connected in series. As a result, the refrigerant circuit (201) enables a so-called two-stage compression refrigeration cycle in which the refrigerant is compressed in two stages by the low-stage compressor (202) and the high-stage compressor (203). Yes.

  Further, the refrigerant circuit (201) of the figure is provided with two four-way switching valves (207, 208) as a mechanism for switching the refrigerant flow path. Specifically, in this air conditioner, after the refrigerant is compressed by the first four-way switching valve (207) for switching between the cooling operation and the heating operation by switching the refrigerant circulation direction, and the low-stage compressor (202). A second four-way switching valve (208) is provided for supplying intermediate pressure refrigerant to the intercooler (206) and for stopping the supply. That is, in this air conditioner (200), the cooling operation and the heating operation are switched by switching the communication state of the four ports of the first four-way switching valve. In the cooling operation, the first operation and the second operation are switched during the cooling operation by switching the communication state of the four ports of the second four-way switching valve (208). In the first operation, the refrigerant compressed to the intermediate pressure by the low-stage compressor (202) is sent to the high-stage compressor (203) without passing through the intercooler (206), and this high-stage compressor (203) Compressed to high pressure. On the other hand, in the second operation, the refrigerant compressed to the intermediate pressure by the low-stage compressor (202) is sent to the intercooler (206). In the intercooler (206), the refrigerant is cooled by outdoor air or the like. Thereby, the temperature of the refrigerant | coolant sent to the high stage side compressor (203) after that becomes lower than the said 1st operation | movement. As a result, in the second operation, the power required to compress the refrigerant in the high stage compressor (203) is reduced, and the energy saving performance of the air conditioner is improved.

  As described above, in the refrigerant circuit of the air conditioner, when the refrigerant flow paths are changed to a plurality of types, the mechanism for switching the refrigerant flow paths becomes complicated according to the number of the refrigerant flow paths. Specifically, in the reference example shown in FIG. 17 described above, it is necessary to provide the refrigerant circuit (201) with two four-way switching valves (207, 208), connect the pipe to each port, and seal one end of the pipe. . As a result, there arises a problem that the switching mechanism of the refrigerant flow path is complicated.

  The present invention has been made in view of such a point, and an object thereof is to provide a refrigerant flow path switching valve capable of switching a refrigerant flow path with a relatively simple structure, and the refrigerant flow path switching valve. It is to propose an air conditioner.

  A first invention is directed to a refrigerant flow path switching valve that switches a refrigerant flow path of a refrigerant circuit (11) in which a refrigeration cycle is performed. The refrigerant flow switching valve includes a drive mechanism (70,145) having an output shaft (74,147), a case portion (80,140) to which the first to sixth ports (91 to 96,131 to 136) are connected, A switching mechanism (100, 150) for switching the communication state of the ports (91 to 96, 131 to 136) by being housed in a case part (80, 140) and being rotationally driven by the output shaft (74, 147); The mechanism (100, 150) has a first angular position for communicating the second port (92, 132) and the third port (93, 133) and the fourth port (94, 134) and the fifth port (95, 135), and the first port. (91,131) and the second port (92,132) and the fourth port (94,134) and the fifth port (95,135) are connected at a second angular position, and the first port (91,131) and the second port ( 92,132) and the fourth port (94,134) and the sixth port (96,136). And a third angular position that, characterized in that it is configured to displace.

  In the refrigerant flow switching valve of the first invention, six ports (91 to 96, 131 to 136) are connected to the case portion (80, 140). A switching mechanism (100, 150) is provided in the case part (80, 140). When the output shaft (74) is rotationally driven by the drive mechanism (70,), the switching mechanism (100, 150) is also rotationally driven and displaced. Accordingly, in the refrigerant flow path switching valve, the switching mechanism (100, 150) is displaced to the first to third angular positions.

  Specifically, when the switching mechanism (100, 150) is displaced to the first angular position, the second port (92, 132) communicates with the third port (93, 133), and the fourth port (94, 134) and the fifth port (95, 135) communicate with each other. Communicate. As a result, the refrigerant flowing through the second port (92,132) can be sent to the third port (93,133) and simultaneously, the refrigerant flowing through the fourth port (94,134) can be sent to the fifth port (95,135). When the switching mechanism (100, 150) is displaced to the second angular position, the first port (91, 131) communicates with the second port (92, 132), and the fourth port (94, 134) communicates with the fifth port (95, 135). As a result, the refrigerant flowing through the first port (91, 131) can be sent to the second port (92, 132), and at the same time, the refrigerant flowing through the fourth port (94, 134) can be sent to the fifth port (95, 135). Further, when the switching mechanism (100, 150) is displaced to the third angular position, the first port (91, 131) communicates with the second port (92, 132) and the fourth port (94, 134) communicates with the sixth port (96, 136). To do. As a result, the refrigerant flowing through the first port (91, 131) can be sent to the second port (92, 132), and at the same time, the refrigerant flowing through the fourth port (94, 134) can be sent to the sixth port (96, 136).

  As described above, in the present invention, at least three types of refrigerant flow paths can be formed by displacing the switching mechanism (100, 150) to three angular positions using one drive mechanism (70, 145). That is, for example, in the example shown in FIG. 17, it is necessary to provide four ports for each four-way switching valve or to control each four-way switching valve separately with different driving sources. On the other hand, in the present invention, since the number of ports (91 to 96, 131 to 136) is reduced, the number of refrigerant pipes connected to each port (91 to 96, 131 to 136) can also be reduced. Moreover, the communication state of each port (91-96,131-136) can be switched only with one drive source (drive mechanism (70,145)).

  According to a second aspect, in the first aspect, the case portion (80) is stacked in two stages in the axial direction of the output shaft (74) and is formed around the output shaft. A storage chamber (85) and a second storage chamber (86) are formed, and the first to third ports (91 to 93) are connected to the first storage chamber (85), and the fourth to fourth ports Up to 6 ports (94 to 96) are connected to the second storage chamber (86), and the switching mechanism (100) is stored in the first storage chamber (85) and rotates to the output shaft (74). By being driven, the first switching unit (110) that switches the communication state of the first to third ports (91 to 93) and the second storage chamber (86) are accommodated in the output shaft (74). ), The second switching unit (120) for switching the communication state of the fourth to sixth ports (94 to 96).

  In the second invention, in the case portion (80), the first storage chamber (85) and the second storage chamber (86) are formed in two stages in the axial direction. A first switching unit (110) is accommodated in the first accommodation chamber (85), and a second switching unit (120) is accommodated in the second accommodation chamber (86). The output shaft (74) is connected to both the first switching unit (110) and the second switching unit (120). Thereby, when the output shaft (74) of the drive mechanism (70) rotates, the first switching unit (110) and the second switching unit (120) are simultaneously displaced. As a result, in the first storage chamber (85), the communication states of the first to third ports (91 to 93) are switched, and in the second storage chamber (86), the fourth to sixth ports ( The communication status from 94 to 96) is switched.

  In a third aspect based on the second aspect, the ports (91 to 96) are connected to the case portion (80) so as to open in the axial end surfaces of the corresponding storage chambers (85, 86). The first switching portion (110) is formed in a substantially cylindrical shape extending across both axial ends of the first storage chamber (85), and the first storage chamber (85) is connected to a first inner chamber ( IS1) and an outer first outer chamber (OS1) having a first partition portion (111), and the second switching portion (120) is provided at both axial ends of the second storage chamber (86). A second partition portion (121) formed in a substantially cylindrical shape extending across the second storage chamber (86) into an inner second inner chamber (IS2) and an outer second outer chamber (OS2). One or both of the inner chambers (IS1, IS2) and the outer chambers (OS1, OS2) of each of the storage chambers (85, 86), corresponding to the rotation of each partition (111, 121). Turn off the open state of the port (91 to 96) It is characterized by constituting a communication path to be replaced.

  In the third invention, the first to third ports (91 to 93) open in the axial end surface of the first storage chamber (85), and the fourth to sixth ports (94 to 96). And opens in the axial end surface of the second storage chamber (86). A cylindrical first partition portion (111) is accommodated in the first accommodation chamber (85). Thereby, the first storage chamber (85) is divided into a first outer chamber (OS1) outside the first partition (111) and a first inner chamber (IS1) inside the first partition (111). Partitioned. Similarly, the cylindrical second partition portion (121) is accommodated in the second accommodation chamber (86). As a result, the second storage chamber (86) is divided into a second outer chamber (OS2) outside the second partition (121) and a second inner chamber (IS2) inside the second partition (121). Partitioned. When the output shaft (74) of the drive mechanism (70) rotates, the first partition (111) and the second partition (121) are simultaneously driven to rotate.

  In the first storage chamber (85), the open ends of the first to third ports (91 to 93) are connected to the first inner chamber (IS1) and the first outer chamber (OS1) of the first partition (111). ). Here, when the first partition portion (111) rotates, the positions of the first inner chamber (IS1) and the first outer chamber (OS1) partitioned by the first storage chamber (85) are also changed. As a result, the communication states of the first to third ports (91 to 93) are switched. Similarly, in the second storage chamber (86), the open ends of the fourth to sixth ports (94 to 96) are the second inner chamber (IS2) and the second outer chamber of the second partition (121). Communicate through (OS2). Here, when the second partition portion (121) rotates, the positions of the second inner chamber (IS2) and the second outer chamber (OS2) partitioned by the second storage chamber (86) are also changed. as a result. The communication states of the fourth to sixth ports (94 to 96) are also switched.

  In a fourth aspect based on the third aspect, the partition portions (111, 121) are formed in an arc shape so as to extend around the axis of the output shaft (74), and the openings of the ports (91 to 96). The ends are arranged around the axis of the output shaft (74) so as to straddle the rotation trajectory of the corresponding partition portion (111, 121).

  In the fourth invention, in the first storage chamber (85), the arc-shaped first partition portion (111) is formed around the axis of the output shaft (74). The open ends of the first to third ports (91 to 93) are arranged so as to straddle the rotation trajectory of the first partition portion (111). As a result, the first partition part (111) is rotated so that each of the first to third ports (91 to 93) through the first inner chamber (IS1) and the first outer chamber (OS1). The communication status is switched. In the second storage chamber (86), an arc-shaped second partition portion (121) is formed around the axis of the output shaft (74). The open ends of the fourth to sixth ports (94 to 96) are arranged so as to straddle the rotation locus of the second partition portion (121). As a result, the second partition part (121) is rotated so that each of the fourth to sixth ports (94 to 96) through the second inner chamber (IS2) and the second outer chamber (OS2). The communication status is switched.

  According to a fifth invention, in the third or fourth invention, the case portion (140) includes a first outer chamber and a second outer chamber (OS2) in a range from the first angular position to the third angular position. And an internal communication path (87) is formed.

  In the fifth invention, the first outer chamber (OS1) and the second outer chamber (OS2) are connected to the internal communication passage (87) in the range from the first angle position to the third angle position of each partition portion (111, 121). Communicate via Thereby, the pressure of the first outer chamber (OS1) and the second outer chamber (OS2) becomes the same pressure. In this way, the first outer chamber (OS1) and the second outer chamber (OS2) are structured to have the same pressure atmosphere. Here, if the first outer chamber (OS1) and the second outer chamber (OS2) have different pressures, the first outer chamber (OS1) and the second outer chamber are arranged around the output shaft (74). A seal mechanism for prohibiting the circulation of the refrigerant with (OS2) is required. In contrast, in the present invention, both the outer chambers (OS1, OS2) can be set to the same pressure, and thus such a sealing mechanism is not necessary.

  In a sixth aspect based on the first aspect, the case portion (140) forms one flat cylindrical storage chamber (144) around the output shaft (74). To the sixth port (131-136) are connected to the one storage chamber (144), and the switching mechanism (100) is formed in a disc shape that is stored in the one storage chamber (144). It includes a disk-shaped switching unit (153) having a plurality of internal passages (C1 to C14) that switches the communication state of each port (131 to 136) by being rotationally driven by the output shaft (74). Features.

  In the sixth invention, one flat storage chamber (144) is formed in the case portion (140), and six ports (131 to 136) are connected to the storage chamber (144). When the disk-shaped switching unit (153) in the storage chamber (144) is rotationally driven by the output shaft (74), a plurality of internal passages (C1 to C14) formed in the disk-shaped switching unit (153) The communication status of each port (131 to 136) switches. As a result, the communication states of the six ports (131 to 136) are switched.

  The seventh invention is directed to an air conditioner. The air conditioner includes a low-stage compressor (22) and a high-stage compressor (23), and a discharge side of the low-stage compressor (22) and an intake of the high-stage compressor (23). First and second branch passages (31, 32) connected in parallel to the side, a cooling mechanism (35) connected to the second branch passage (32), and an outdoor heat exchanger (24 ), An indoor heat exchanger (43a, 43b, 43c), and a refrigerant flow path switching valve (60, 130) according to any one of claims 1 to 6, wherein a refrigerant circuit in which a refrigeration cycle is performed (11), wherein the refrigerant flow path switching valve (60, 130) has the first port (91, 131) connected to the high-pressure line (29) on the discharge side of the high-stage compressor (23), Two ports (92, 132) are connected to one end of the outdoor heat exchanger (24), and the third port (93, 133) is connected to a low-pressure line (26) on the suction side of the low-stage compressor (22). Connected, the fourth The port (94,134) is connected to the discharge line (27) on the discharge side of the low-stage compressor (22), the fifth port (95,135) is connected to the first branch (31), The sixth port (96, 136) is connected to the second branch path (32).

  In the air conditioner according to the seventh aspect of the present invention, the angular position of the switching mechanism (100, 150) of the refrigerant flow path switching valve (60, 130) is displaced to the first to third angular positions, so that three operations can be executed. It becomes. Specifically, when the refrigerant flow path switching valve (100, 150) is in the first angular position, the second port (92, 132) and the third port (93, 133) communicate with each other. In this state, one end of the outdoor heat exchanger (24) communicates with the suction side of the low-stage compressor (22). As a result, in the refrigerant circuit (11), the low-pressure refrigerant flows through the outdoor heat exchanger (24), and the low-pressure refrigerant evaporates. That is, in this state, it is possible to execute a refrigeration cycle (that is, a heating cycle) in which the indoor heat exchangers (43a, 43b, 43c) are radiators (condensers) and the outdoor heat exchanger (24) is an evaporator. Further, when the refrigerant flow path switching valve (60, 130) is at the first angular position, the fourth port (94, 134) and the fifth port (95, 135) communicate with each other. In this state, the discharge line (27) on the discharge side of the low-stage compressor (22) communicates with the first branch path (31). As a result, the refrigerant compressed by the low stage compressor (22) is sent to the high stage compressor (23) through the first branch path (31) and further compressed. In other words, in this state, during the heating operation, a two-stage compression refrigeration cycle is performed in which the refrigerant compressed to the intermediate pressure by the low-stage compressor (22) is compressed to a high pressure by the high-stage compressor (23). Is called.

  When the refrigerant flow path switching valve (60, 130) is in the second angular position, the first port (91, 131) and the second port (92, 132) communicate with each other. In this state, the discharge side of the high stage compressor (23) communicates with one end of the outdoor heat exchanger (24). As a result, in the refrigerant circuit (11), the high-pressure refrigerant flows through the outdoor heat exchanger (24), and the high-pressure refrigerant radiates heat to the outdoor air. That is, in this state, it is possible to execute a refrigeration cycle (that is, a cooling cycle) in which the outdoor heat exchanger (24) is a radiator (condenser) and the indoor heat exchangers (43a, 43b, 43c) are evaporators. Further, when the refrigerant flow path switching valve (60, 130) is in the second angular position, the fourth port (94, 134) and the fifth port (95, 135) communicate with each other. In this state, the discharge line (27) on the discharge side of the low-stage compressor (22) communicates with the first branch path (31). As a result, the refrigerant compressed by the low stage compressor (22) is sent to the high stage compressor (23) through the first branch path (31) and further compressed. That is, in this state, during the cooling operation, a two-stage compression refrigeration cycle is performed in which the refrigerant compressed to the intermediate pressure by the low-stage compressor (22) is compressed to a high pressure by the high-stage compressor (23). Is called.

  When the refrigerant flow path switching valve (60, 130) is in the third angular position, the first port (91, 131) and the second port (92, 132) communicate with each other. Therefore, even in this state, the refrigerant circuit (11) can execute the cooling cycle. Further, when the refrigerant flow path switching valve (60, 130) is in the third angular position, the fourth port (94, 134) and the sixth port (96, 136) communicate with each other. In this state, the discharge line (27) on the discharge side of the low-stage compressor (22) communicates with the second branch path (32). As a result, the refrigerant compressed by the low stage compressor (22) flows through the second branch path (32). Here, the second branch path (32) is provided with a cooling mechanism (35) for cooling the refrigerant. For this reason, the intermediate pressure refrigerant flowing through the second branch path (32) is cooled by the cooling mechanism (35). The refrigerant cooled by the cooling mechanism (35) is sent to the high stage compressor (23) and further compressed. Thus, when the refrigerant sucked into the high stage compressor (23) is cooled, the compression power required to compress the refrigerant to a high pressure is reduced. As described above, in this state, during the cooling operation, the intermediate-pressure refrigerant is cooled by the cooling mechanism (35), so that the energy saving performance in the cooling operation is improved.

  According to the present invention, six ports (91 to 96, 131 to 136) are connected to the case portion (80, 140), and the switching mechanism (100, 150) is rotationally driven between three angular positions by the drive mechanism (70, 145). The communication state of each port (91 to 96, 131 to 136) is switched. For this reason, since the communication state of each port (91-96, 131-136) can be switched by one drive source, the structure of the refrigerant flow path switching valve can be simplified. In addition, since the switching mechanism (100, 150) is rotated to switch the communication state, the switching mechanism (100, 150) can be easily driven even if there is no refrigerant pressure difference as in the four-way switching valve of the reference example. Further, unlike the four-way switching valve of the reference example, the communication state can be maintained in a predetermined state without always energizing, and thus energy saving can be improved.

  In the second invention, the two storage chambers (85, 86) are stacked in two stages in the axial direction, and the switching portions (110, 120) of the storage chambers (85, 86) are simultaneously driven to set the ports (91 to 96, 131 to 136) The communication state is switched. For this reason, it is possible to avoid the refrigerant flow path switching valve (60, 130) from being enlarged in the direction perpendicular to the axis.

  In the third aspect of the invention, each of the storage chambers (85, 86) is provided with a cylindrical partition (111, 121), and the outer chamber (OS1, OS2) and the inner chamber (IS1, IS2) of each partition (111, 121) It is used as a communication path for each port (91 to 96). For this reason, simplification of the switching mechanism (100) can be achieved.

  In particular, in the fourth invention, an arcuate partition (111, 121) is provided around the axis of the output shaft (74), and each port (91-96) is opened so as to straddle the rotation locus of the partition (111, 121). The ends are arranged. Thereby, the space of the storage chamber (85, 86) can be used effectively, and the switching mechanism (100) can be downsized in the radial direction.

  In the fifth aspect of the invention, the first outer chamber (OS1) and the second outer chamber (OS2) are communicated with each other through the internal communication passage (87). The pressure difference with OS2) can be reduced. As a result, it is not necessary to seal the gap around the output shaft (74), and the structure of the refrigerant flow path switching valve can be simplified.

  In the sixth invention, one flat storage chamber (144) is formed in the case portion (140), and the disk-shaped switching portion (153) in the storage chamber (144) is rotationally driven, whereby 6 The communication state of the two ports (131 to 136) is switched. Thereby, in this invention, a refrigerant | coolant flow path switching valve can be reduced in size in an axial direction.

  In the seventh invention, the refrigerant circuit (11) of the air conditioner uses the refrigerant flow switching valve (60, 130) of the first to sixth inventions to switch the three operations. Specifically, in the present invention, the refrigerant flow switching valve (60, 130) is displaced to the first to third angular positions, so that the first operation of the heating operation and the cooling operation (the intermediate pressure refrigerant is cooled by the cooling mechanism). Bypass operation for further compression with the high-stage compressor (23)) and second operation of the cooling operation (operation for cooling the intermediate-pressure refrigerant with the cooling mechanism and further compressing with the high-stage compressor (23)) ) Can be switched. Accordingly, for example, the number of refrigerant flow switching valves, the number of ports, the number of refrigerant pipes, and the like can be reduced as compared with the refrigerant circuit of the reference example shown in FIG.

1 is a piping system diagram of a refrigerant circuit of an air-conditioning apparatus according to Embodiment 1. FIG. FIG. 2 is a perspective view showing the overall configuration of the composite valve according to the first embodiment, and shows a part of the case unit seen through. 3 is a cross-sectional view taken along line III-III in FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 5 is a cross-sectional view taken along line VV in FIG. 6 is an enlarged view of the composite valve switching mechanism according to the first embodiment, corresponding to FIG. 7 is a view corresponding to FIGS. 4 and 5 for explaining the change in the switching state (angular position of the switching mechanism) of the composite valve according to the first embodiment, and FIG. 7 (A) is the first angular position, FIG. 7 (B) represents the second angular position, and FIG. 7 (C) represents the third angular position. FIG. 8 is a piping system diagram of the refrigerant circuit of the air-conditioning apparatus according to Embodiment 1, to which a refrigerant flow during heating operation is added. FIG. 9 is a piping system diagram of the refrigerant circuit of the air-conditioning apparatus according to Embodiment 1, to which the refrigerant flow during the first operation of the cooling operation is added. FIG. 10 is a piping system diagram of the refrigerant circuit of the air-conditioning apparatus according to Embodiment 1, to which a refrigerant flow during the second operation of the cooling operation is added. FIG. 11 is a piping system diagram of the refrigerant circuit of the air-conditioning apparatus according to Embodiment 2. FIG. 12 is an exploded perspective view of the rotary valve according to the second embodiment. FIG. 13 is a cross-sectional view perpendicular to the axis of the rotary valve according to the second embodiment. FIG. 14 is a piping system diagram of a refrigerant circuit of the air-conditioning apparatus according to Embodiment 2, to which a refrigerant flow during heating operation is added. FIG. 15 is a piping system diagram of the refrigerant circuit of the air-conditioning apparatus according to Embodiment 2, to which a refrigerant flow in the first operation of the cooling operation is added. FIG. 16 is a piping system diagram of the refrigerant circuit of the air-conditioning apparatus according to Embodiment 2, to which a refrigerant flow in the second operation of the cooling operation is added. FIG. 17 illustrates a part of the refrigerant circuit of the air conditioner according to the reference example.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following embodiments are essentially preferable examples, and are not intended to limit the scope of the present invention, its application, or its use.

Embodiment 1 of the Invention
The composite valve (60) according to Embodiment 1 of the present invention is applied to the air conditioner (10). The air conditioner (10) constitutes a refrigeration apparatus that performs a refrigeration cycle by circulating refrigerant. The air conditioner (10) is a heat pump type that switches between indoor cooling and heating. As shown in FIG. 1, the air conditioner (10) is a so-called multi-type that has one outdoor unit (20) and a plurality of indoor units (40a, 40b, 40c). In this embodiment, the air conditioner (10) has three indoor units (40a, 40b, 40c), but this quantity is merely an example, and any quantity may be used. The air conditioner (10) has a plurality of switching units (50a, 50b, 50c) (hereinafter referred to as BS units (50a, 50b, 50c)) corresponding to the indoor units (40a, 40b, 40c). Yes. The air conditioner (10) is a so-called cooling / heating-free type (a system in which a cooling operation is performed in at least one indoor unit and a heating operation is performed in at least one indoor unit at the same time).

  The outdoor unit (20) is installed outdoors. The outdoor unit (20) has an outdoor circuit (21) forming a heat source side circuit. Each indoor unit (40a, 40b, 40c) is installed indoors. Each indoor unit (40a, 40b, 40c) has an indoor circuit (41a, 41b, 41c) that constitutes a use side circuit. Each BS unit (50a, 50b, 50c) has a switching circuit (51a, 51b, 51c), respectively. In the air conditioner (10), an outdoor circuit (21), each indoor circuit (41a, 41b, 41c), and each switching circuit (50a, 50b, 50c) are connected to form a refrigerant circuit (closed circuit) 11) is configured. The refrigerant circuit (11) of the present embodiment is filled with carbon dioxide as a refrigerant. That is, in the refrigerant circuit (11), a so-called supercritical cycle in which carbon dioxide is compressed to a critical pressure or higher is performed.

<Outdoor unit>
The outdoor circuit (21) of the outdoor unit (20) includes a low stage compressor (22), a high stage compressor (23), an outdoor heat exchanger (24), and an outdoor expansion valve (25). ing.

  The low stage side compressor (22) and the high stage side compressor (23) are constituted by, for example, a scroll compressor. Moreover, the low stage side compressor (22) and the high stage side compressor (23) are comprised by the inverter type | mold with variable capacity | capacitance. The low stage side suction pipe (26) is connected to the suction side of the low stage side compressor (22), and the low stage side discharge pipe (27) is connected to the discharge side of the low stage side compressor (22). Has been. The high stage side suction pipe (28) is connected to the suction side of the high stage side compressor (23), and the high stage side discharge pipe (29) is connected to the discharge side of the high stage side compressor (23). Has been. In the outdoor circuit (21), the low-pressure refrigerant is compressed to an intermediate pressure by the low-stage compressor (22), and the intermediate-pressure refrigerant is compressed to a high pressure by the high-stage compressor (23). That is, in the refrigerant circuit (11), a two-stage compression refrigeration cycle in which the refrigerant is compressed in two stages is performed.

  The outdoor heat exchanger (24) constitutes a heat source side heat exchanger. The outdoor heat exchanger (24) is configured, for example, as a fin and tube type. In the vicinity of the outdoor heat exchanger (24), an outdoor fan (not shown) as a blower mechanism is provided. In the outdoor heat exchanger (24), the outdoor air blown by the outdoor fan and the refrigerant exchange heat.

  The outdoor expansion valve (25) constitutes an expansion mechanism that expands the refrigerant. The outdoor expansion valve (25) is composed of, for example, an electronic expansion valve whose opening degree can be freely opened and closed.

  A first branch pipe (31) forming a first branch path and a second branch path are formed between the discharge side of the low stage compressor (22) and the suction side of the high stage compressor (23). The second branch pipe (32) is connected in parallel. The first branch pipe (31) is provided with a first check valve (33). The second branch pipe (32) is provided with a second check valve (34). The first check valve (33) allows the refrigerant to flow from the low-stage compressor (22) to the high-stage compressor (23), while the high-stage compressor (23) Prohibit refrigerant flow to compressor (22). Similarly, the second check valve (34) allows the refrigerant to flow from the low-stage compressor (22) to the high-stage compressor (23), while from the high-stage compressor (23). Prohibit refrigerant flow to the low-stage compressor (22).

  The second branch pipe (32) is provided with an intercooler (35) on the downstream side of the second check valve (34). The intercooler (35) cools the intermediate pressure refrigerant compressed by the low-stage compressor (22). That is, the intercooler (35) constitutes a cooling mechanism that cools the refrigerant during the compression stroke of the refrigeration cycle. Specifically, the intercooler (35) includes an air heat exchanger that exchanges heat between refrigerant and air. A cooling fan (not shown) is provided in the vicinity of the intercooler (35). In the intercooler (35), the air (for example, outdoor air) blown by the cooling fan exchanges heat with the refrigerant, and the refrigerant is cooled. Note that another type of cooling mechanism may be employed as a cooling mechanism for cooling the intermediate-pressure refrigerant.

  The outdoor circuit (21) is provided with a composite valve (60) that constitutes a refrigerant flow path switching valve that switches the flow path of the refrigerant. The compound valve (60) includes a lower blocking portion (83) to which the first to third ports (91, 92, 93) are connected, and a fourth port to a sixth port (94, 95, 96). ) Are connected to the upper closing part (82) to form an integral unit. The first port (91) is connected to the high stage discharge pipe (29) (that is, the high pressure line) via the high pressure branch pipe (36). The second port (92) is connected to the low-stage suction pipe (26) (that is, the low-pressure line) via the low-pressure branch pipe (37). The third port (93) is connected to the gas side end of the outdoor heat exchanger (24). The fourth port (94) is connected to the lower stage discharge pipe (27) (that is, the discharge line) of the lower stage compressor (22). The fifth port (95) is connected to the inflow end of the first branch pipe (31). The sixth port (96) is connected to the inflow end of the second branch pipe (32).

  The composite valve (60) is configured to switch to the first to third states. In the first state (the state shown in FIG. 1), the second port (92) and the third port (93) communicate with each other and the first port (91) closes. The sixth port (96) is closed by communicating with the port (95). In the second state (the state shown in FIG. 9), the first port (91) and the third port (93) communicate with each other and the second port (92) closes, and at the same time, the fourth port (94) and the fifth port (94) The sixth port (96) is closed by communicating with the port (95). In the third state (the state shown in FIG. 10), the first port (91) and the third port (93) communicate with each other to close the second port (92), and at the same time the fourth port (94) and the sixth port The fifth port (95) is closed by communicating with the port (96). Details of the structure and switching operation of the composite valve (60) will be described later.

<Indoor unit>
The air conditioner (10) has three indoor units (40a, 40b, 40c). Each indoor unit (40a, 40b, 40c) is installed in a room of a different room. Each indoor unit (40a, 40b, 40c) has an indoor circuit (41a, 41b, 41c) as a use side circuit. One end of each indoor circuit (41a, 41b, 41c) is connected to the liquid pipe (12). The indoor expansion valves (42a, 42b, 42c) and the indoor heat exchangers (43a, 43b, 43c) are sequentially connected to the indoor circuits (41a, 41b, 41c) from the liquid pipe (12) side. The indoor expansion valves (42a, 42b, 42c) constitute an expansion mechanism that expands the refrigerant. The indoor expansion valves (42a, 42b, 42c) are constituted by, for example, electronic expansion valves whose opening degree can be freely opened and closed. In the vicinity of the indoor heat exchangers (43a, 43b, 43c), an indoor fan (not shown) as a blower mechanism is provided. In the indoor heat exchanger (43a, 43b, 43c), the indoor air blown by the indoor fan and the refrigerant exchange heat.

<BS unit>
The air conditioner (10) has three BS units (50a, 50b, 50c) corresponding to each indoor unit (40a, 40b, 40c). Each BS unit (50a, 50b, 50c) has a switching circuit (51a, 51b, 51c), respectively. Each switching circuit (51a, 51b, 51c) has a junction pipe (52a, 52b, 52c) connected to the other end of the indoor circuit (41a, 41b, 41c). Each switching circuit (51a, 51b, 51c) includes a first branch pipe (53a, 53b, 53c) and a second branch pipe (54a, 54b, 54c). Each first branch pipe (53a, 53b, 53c) has one end connected to the merge pipe (52a, 52b, 52c) and the other end connected to the high pressure gas pipe (13). Each of the second branch pipes (54a, 54b, 54c) has one end connected to the junction pipe (52a, 52b, 52c) and the other end connected to the low-pressure gas pipe (14). Each first branch pipe (53a, 53b, 53c) is provided with a first opening / closing valve (55a, 55b, 55c) as an opening / closing mechanism. Each of the second branch pipes (54a, 54b, 54c) is provided with a second on-off valve (56a, 56b, 56c) as an opening / closing mechanism.

<Structure of compound valve>
As described above, the composite valve (60) is connected to the refrigerant circuit (11) of the air conditioner (10). As shown in FIGS. 2 and 3, the composite valve (60) includes a case unit (61), a drive mechanism (70), and a switching mechanism (100).

  The case unit (61) has a cylindrical case part (62) whose outer shape is generally cylindrical, and a cap-shaped motor case part (63) formed at the upper end of the cylindrical case part (62). . The motor case part (63) has a hemispherical upper end and an opening at the lower end. The cylindrical case part (62) has a gear case part (64) formed above a substantially intermediate position in the axial direction and a valve case part (80) formed below the intermediate position. Yes. The gear case portion (64) includes an upper lid portion (65) on which the motor case portion (63) is erected and a cylindrical portion (66) formed on the lower side of the upper lid portion (65). .

  The drive mechanism (70) has a motor (71), a motor drive shaft (72), a transmission gear (73), and an output shaft (74). The motor (71) is accommodated in the motor case part (63). A motor drive shaft (72) that is rotationally driven by the motor (71) is connected to the lower end of the motor (71). The motor drive shaft (72) extends through the upper lid (65) into the cylinder (66) and is connected to the transmission gear (73). An output shaft (74) is connected to the lower end of the transmission gear (73). The output shaft (74) extends downward in the valve case portion (80).

  The valve case part (80) has a cylindrical cover (81), an upper closing part (82), a lower closing part (83), and an intermediate plate (84).

  The cylindrical cover (81) is formed in a cylindrical shape interposed between the upper closing portion (82) and the lower closing portion (83). The upper closing part (82) is formed in a substantially disk shape that is flat vertically, and closes the lower end of the gear case part (64) and the upper end of the cylindrical cover (81). The lower closing part (83) is formed in a substantially disk shape that is flat up and down, and closes the lower end of the cylindrical cover (81) to constitute the bottom part of the cylindrical case part (62).

  The intermediate plate (84) partitions the inside of the cylindrical cover (81) into two spaces (85, 86) vertically in the axial direction. Specifically, a ring-shaped lower spacer (75) is provided between the cylindrical cover (81), the lower closing portion (83), and the intermediate plate (84) along the inner wall of the cylindrical cover (81). ) Is provided. And between the cylindrical cover (81) (strictly speaking, the inner peripheral surface of the lower spacer (75)), the upper surface of the lower blocking portion (83), and the lower surface of the intermediate plate (84), A substantially cylindrical first storage chamber (85) is formed. Similarly, a ring-shaped upper spacer (76) is interposed between the cylindrical cover (81), the upper closing portion (82), and the intermediate plate (84) along the inner wall of the cylindrical cover (81). It is installed. Between the cylindrical cover (81) (strictly speaking, the inner peripheral surface of the upper spacer (76)), the lower surface of the upper closing portion (82), and the upper surface of the intermediate plate (84), A cylindrical second storage chamber (86) is formed.

  The output shaft (74) passes through the shaft center of the lower blocking portion (83). A rotation support member (77) that rotatably holds the lower end surface of the output shaft (74) is provided at the upper end of the shaft center portion of the lower closing portion (83). Further, the first port (91), the second port (92), and the third port (93) described above are connected to the lower blocking portion (83). The ends of the first to third ports (91, 92, 93) are inserted through the outer peripheral surface of the lower blocking portion (83). Three internal communication passages (97, 97) communicating with the first port (91), the second port (92), and the third port (93) in the lower blocking portion (83), respectively. , 97) is formed. Each of the internal communication passages (97) includes a radial passage (97a) extending in the radial direction and an axially upwardly bent end from the inner peripheral side end of the radial passage (97a) into the first storage chamber (85). Each has an axial passage (97b) communicating therewith. That is, on the lower surface of the first storage chamber (85), there are a first opening (91a) serving as an opening end of the internal communication path (97) corresponding to the first port (91) and a second port (92). A second opening (92a) serving as an opening end of the corresponding internal communication path (97), and a third opening (93a) serving as an opening end of the internal communication path (97) corresponding to the third port (93). Is formed (see FIG. 4).

  The output shaft (74) penetrates the shaft center of the upper closing part (82). Further, the above-described fourth port (94), fifth port (95), and sixth port (96) are connected to the upper closing part (82). The ends of the fourth to sixth ports (94, 95, 96) are inserted through the outer peripheral surface of the upper closing portion (82). Three internal communication passages (98, 98, 98) that communicate with the fourth port (94), the fifth port (95), and the sixth port (96), respectively, inside the upper blocking portion (82). 98) is formed. Each of the internal communication passages (98) has a radial passage (98a) extending in the radial direction, and is bent downward in the axial direction from the inner peripheral side end portion of the radial passage (98a) into the second storage chamber (86). Each has an axial passage (98b) communicating therewith. That is, on the upper surface of the second storage chamber (86), the fourth opening (94a) serving as the opening end of the internal communication passage (98) corresponding to the fourth port (94) and the fifth port (95) are provided. A fifth opening (95a) serving as an opening end of the corresponding internal communication path (98), and a sixth opening (96a) serving as an opening end of the internal communication path (98) corresponding to the sixth port (96). Is formed (see FIG. 5).

  The output shaft (74) passes through the axis of the intermediate plate (84). The intermediate plate (84) is formed with a communication hole (87) penetrating in the axial direction for communicating the first storage chamber (85) and the second storage chamber (86).

  The switching mechanism (100) of the composite valve (60) is for switching the communication state of the first to sixth ports (91, 92, 93, 94, 95, 96). As shown in FIGS. 3 to 6, the switching mechanism (100) includes a first switching portion (110) accommodated in the first accommodation chamber (85) and a second accommodation accommodated in the second accommodation chamber (86). And a switching unit (120). Further, a rod-like positioning pin (101) is erected in the second storage chamber (86) in the axial direction (see, for example, FIGS. 3 and 5).

  The first switching unit (110) is configured to switch the communication state of the first to third ports (91, 92, 93) by being rotationally driven by the output shaft (74). The 1st switching part (110) has the 1st gate valve (111) which comprises a cylindrical 1st partition part. The first gate valve (111) includes a first body portion (112), a pair of first O-rings (113, 113), and a pair of first packings (114, 114).

  The first main body (112) is composed of the same member as the output shaft (74) and is integrally formed with the output shaft (74). The first body portion (112) includes a first cylindrical valve portion (115) formed along the axis of the output shaft (74), and the first cylindrical valve portion (115) and the output shaft (74). And a connecting portion (116) for integrally connecting them.

  As shown in FIG. 4, the first cylindrical valve portion (115) has a rough outer shape in a direction perpendicular to the axis formed in an arc shape, a bowl shape, or a fan shape along the output shaft (74). . The first tubular valve portion (115) is formed over a range of about 120 ° in the circumferential direction around the axis of the output shaft (74). As shown in FIG. 6, a cylindrical convex portion (117) is formed at an intermediate portion in the axial direction inside the first cylindrical valve portion (115). The cylindrical convex portion (117) is formed over the entire inner circumference of the first cylindrical valve portion (115). Thereby, large-diameter openings (118, 118) are formed on both sides in the axial direction of the cylindrical convex portion (117) of the first cylindrical valve portion (115). That is, the large-diameter opening (118, 118) has an opening width wider than the inside of the cylindrical protrusion (117). Further, the axial length of the first cylindrical valve portion (115) is slightly shorter than the axial interval from the lower closing portion (83) to the intermediate plate (84).

  The first O-rings (113, 113) are fitted into the first main body (112) so as to contact the cylindrical convex portions (117) inside the pair of large-diameter openings (118, 118). The first O-ring (113, 113) is formed in an annular shape along each step surface of the cylindrical convex portion (117). Each of the first O-rings (113, 113) includes a space ((first inner chamber (IS1)) inside the first gate valve (111) and a space (first outer chamber (OS1) outside the first gate valve (111). The sealing member for sealing the clearance gap between ()) is comprised.

  A first packing (114, 114) is fitted into the first main body (112) so as to overlap the first O-ring (113, 113,) inside the pair of large-diameter openings (118, 118). The first packing (114, 114) is formed in an annular shape along the first O-ring (113, 113). A tapered chamfered annular chamfered portion (114a) is formed on the inner opening edge of the first packing (114). Thereby, as for the 1st packing (114), the diameter of the opening is expanding as it goes to an axial direction both ends. The first packing (114) constitutes a seal member for sealing a gap between the first inner chamber (IS1) and the first outer chamber (OS1).

  Each front end portion of the first packing (114, 114) protrudes outward from the axial end surface of the first main body portion (112), and both axial end surfaces (lower surface and upper surface) of the first storage chamber (85). Abut. Thereby, on the outer periphery of the lower first packing (114), between the one end surface (lower end surface) of the first body portion (112) in the axial direction and the lower surface of the first storage chamber (85), A cylindrical gap (G1) is formed. That is, the gap (G1) is formed so as to surround the entire circumference of the lower first packing (114). Similarly, on the outer periphery of the upper first packing (114), there is a cylinder between the other axial end surface (upper end surface) of the first body portion (112) and the upper surface of the first storage chamber (85). A gap (G2) is formed. That is, the gap (G2) is formed so as to surround the entire circumference of the upper first packing (114).

  As described above, in the present embodiment, the back pressure spaces (G1, G2) in which the same pressure acts are formed on both axial ends of the first gate valve (111). Thereby, in the 1st gate valve (111), the pressing force which acts on an axial direction end surface cancels mutually. For example, if a gap is formed only on one axial end surface of the first gate valve (111) and a pressing force acts on this end surface, the first gate valve (111) is pressed to one side. As a result, the sliding resistance when driving the first gate valve (111) increases. However, in this embodiment, since the pressing forces on both sides in the axial direction acting on the first gate valve (111) are canceled each other, such an increase in sliding resistance can be prevented.

  The second switching unit (120) is configured to switch the communication state of the fourth to sixth ports (94, 95, 96) by being rotationally driven by the output shaft (74). The 2nd switching part (120) has the 2nd gate valve (121) which comprises a cylindrical 2nd partition part. The second gate valve (121) includes a second main body (122), a pair of second O-rings (123, 123), and a pair of second packings (124, 124).

  The second main body (122) is configured separately from the output shaft (74) and is connected to the output shaft (74) via the key (102). The second body portion (122) is connected to the second cylindrical valve portion (125) formed along the axis of the output shaft (74), and is connected to the second cylindrical valve portion (125) for output. It has a connection part (126) connected via a shaft (74) and a key (102).

  As shown in FIG. 5, the second cylindrical valve portion (125) has a rough outer shape in a direction perpendicular to the axis formed in an arc shape, a saddle shape, or a fan shape along the output shaft (74). . The second cylindrical valve portion (125) is formed over a range of about 120 ° with the axis of the output shaft (74) as the center. As shown in FIG. 6, the configuration of the second cylindrical valve portion (125) is the same as that of the first cylindrical valve portion (115) described above. That is, the cylindrical convex part (127) is formed in the axial intermediate part of the second cylindrical valve part (125). And the 2nd O-ring (123,123) and the 2nd packing (124,124) are fitting to the both sides of the axial direction of this cylindrical convex part (127). The second O-ring (123, 123) and the second packing (124, 124) are the space inside the second gate valve (121) (second inner chamber (IS2)) and the space outside the second gate valve (121) (first 2 constitutes a sealing member for sealing a gap with the outer chamber (IO2).

  Further, in the second cylindrical valve portion (125), as in the first cylindrical valve portion (115), gaps (G3, G4) as back pressure spaces are formed on the outer periphery of each second packing (124, 124). Each is formed. Thereby, in the second gate valve (121), the pressing force from both sides in the axial direction is canceled as in the case of the first gate valve (111), so that the slide acting on the second gate valve (121) during driving is canceled. Dynamic resistance can be reduced.

<Relationship between the opening of each port and each gate valve>
The positional relationship between the openings (91a to 96a) of the ports (91 to 96) of the composite valve (60) and the two gate valves (111, 121) will be described in detail with reference to FIGS.

  As described above, the first to third openings (91a to 93a) are formed on the lower surface side of the first storage chamber (85). These openings (91a to 93a) are formed in a circular shape having the same diameter. The first to third openings (91a to 93a) are arranged so that their center points are located on a virtual circle p having a predetermined radius centered on the axis of the output shaft (74). Yes. The center point of the first opening (91a) and the center point of the second opening (92a) are approximately 60 ° in the circumferential direction (counterclockwise direction in FIG. 4) about the axis of the output shaft (74). Is made. On the other hand, the center point of the second opening (92a) and the center point of the third opening (93a) are approximately in the circumferential direction (counterclockwise direction in FIG. 4) about the axis of the output shaft (74). It is 120 °.

  The first gate valve (111) is configured to rotate at least in the ranges shown in FIGS. 7A, 7B, and 7C as the output shaft 74 is driven to rotate. ing. Specifically, the first gate valve (111) is rotated by about 60 ° counterclockwise from the first angular position with reference to the angular position (first angular position) shown in FIG. It is displaced over a position (second angular position) and an angular position (third angular position) rotated about 60 ° counterclockwise from the second angular position.

  As described above, the fourth to sixth openings (94a to 96a) are formed on the upper surface side of the second storage chamber (86). These openings (94a to 96a) are formed in a circular shape having the same diameter. The diameters of the fourth to sixth openings (94a to 96a) and the first to third openings (91a to 93a) are also substantially the same. The fourth to sixth openings (94a to 96a) are arranged such that their center points are located on a predetermined virtual circle l centered on the axis of the output shaft (74). Yes. In the present embodiment, the virtual circle p and the virtual circle l have substantially the same radius.

  The center point of the fourth opening (94a) substantially coincides with the center point of the first opening (91a) in the axial direction. The center point of the fourth opening (94a) and the center point of the fifth opening (95a) are about 60 ° in the circumferential direction (clockwise direction in FIG. 5) about the axis of the output shaft (74). It is made. On the other hand, the center point of the fourth opening (94a) and the center point of the sixth opening (96a) are approximately in the circumferential direction (counterclockwise direction in FIG. 5) about the axis of the output shaft (74). It is 120 °.

  The two gate valve (121) has substantially the same outer shape as the first gate valve (111) and is disposed so as to overlap each other in the axial direction. That is, when the output shaft (74) rotates, the first gate valve (111) and the second gate valve (121) are driven synchronously so as to maintain substantially the same angular position.

  The second gate valve (121) is configured to rotate at least in the ranges shown in FIGS. 7A, 7B, and 7C as the output shaft 74 is driven to rotate. ing. Specifically, the second gate valve (121) is rotated by about 60 ° counterclockwise from the first angular position with reference to the angular position (first angular position) shown in FIG. It is displaced over a position (second angular position) and an angular position (third angular position) rotated about 60 ° counterclockwise from the second angular position. In the state where the second gate valve (121) is at the first angular position, the second gate valve (121) and the positioning pin (101) abut. Accordingly, the second gate valve (121) and the first gate valve (111) driven in synchronization with the second gate valve (121) are held at the first angular position.

-Driving action-
First, the basic operation of the air conditioner (10) will be described. In the air conditioner (10), a heating operation for heating the room and a cooling operation for cooling the room are performed. In the cooling operation, a first operation for compressing the intermediate pressure refrigerant without cooling and a second operation for compressing the intermediate pressure refrigerant after being cooled by the intercooler (35) can be performed. .

<Heating operation>
As shown in FIG. 8, in the heating operation, the composite valve (60) is in the first state (that is, the first angular position). Moreover, each 1st on-off valve (55a, 55b, 55c) will be in an open state, and each 2nd on-off valve (56a, 56b, 56c) will be in a closed state. Further, the indoor expansion valves (42a, 42b, 42c) are opened, and the opening degree of the outdoor expansion valve (25) is adjusted as appropriate. When the low-stage compressor (22) and the high-stage compressor (23) are operated in such a state, each indoor heat exchanger (43a, 43b, 43c) becomes a radiator, and the outdoor heat exchanger A refrigeration cycle in which (24) becomes an evaporator is performed.

  Specifically, the refrigerant compressed to the intermediate pressure by the low-stage compressor (22) passes through the fourth port (94) and the fifth port (95), and passes through the first branch pipe (31). Flowing. The refrigerant flowing out of the first branch pipe (31) is compressed to a high pressure by the high stage compressor (23). The high-pressure refrigerant flows into the first branch pipes (53a, 53b, 53c) via the high-pressure gas pipe (13) and flows through the indoor heat exchangers (43a, 43b, 43c). In each indoor heat exchanger (43a, 43b, 43c), the refrigerant radiates heat to the indoor air. Thereby, indoor air is heated.

  The refrigerant radiated by the indoor heat exchangers (43a, 43b, 43c) joins in the liquid pipe (12) and is reduced in pressure in the outdoor expansion valve (25), and then flows in the outdoor heat exchanger (24). In the outdoor heat exchanger (24), the refrigerant absorbs heat from the outdoor air and evaporates. The refrigerant evaporated in the outdoor heat exchanger (24) passes through the third port (93) and the second port (92), and is sucked into the low stage compressor (22) and compressed.

  In such a heating operation, heating can be performed in a part of the plurality of indoor units (40a, 40b, 40c), and cooling can be performed in the rest. That is, for the BS unit (50c) corresponding to the indoor unit to be cooled (for example, the indoor unit (40c)), the first on-off valve (55c) is closed and the second on-off valve (56c) is opened. As a result, part of the high-pressure liquid refrigerant in the liquid pipe (12) flows through the indoor heat exchanger (43c) and evaporates. As a result, the indoor air can be cooled with the refrigerant flowing through the indoor heat exchanger (43c), and at the same time, the indoor air can be heated with the refrigerant flowing through the remaining indoor heat exchangers (43a, 43b).

<First operation of cooling operation>
As shown in FIG. 9, in the first operation of the cooling operation, the composite valve (60) is in the second state (that is, the second angular position). Moreover, each 1st on-off valve (55a, 55b, 55c) will be in a closed state, and each 2nd on-off valve (56a, 56b, 56c) will be in an open state. Further, the outdoor expansion valve (25) is opened, and the opening degree of each indoor expansion valve (42a, 42b, 42c) is appropriately adjusted. In this state, when the low-stage compressor (22) and the high-stage compressor (23) are operated, the outdoor heat exchanger (24) becomes a radiator, and each indoor heat exchanger (43a, 43b , 43c) is used as an evaporator.

  Specifically, the refrigerant compressed to the intermediate pressure by the low-stage compressor (22) passes through the fourth port (94) and the fifth port (95), and passes through the first branch pipe (31). Flowing. The refrigerant flowing out of the first branch pipe (31) is compressed to a high pressure by the high stage compressor (23). The high-pressure refrigerant passes through the first port (91) and the third port (93) via the high-pressure branch pipe (36) and flows through the outdoor heat exchanger (24). In the outdoor heat exchanger (24), the refrigerant radiates heat to the outdoor air.

  The refrigerant radiated by the outdoor heat exchanger (24) is divided into each indoor circuit (41) via the liquid pipe (12). The refrigerant flowing into each indoor circuit (41) is depressurized by each indoor expansion valve (42a, 42b, 42c) and then flows through each indoor heat exchanger (43a, 43b, 43c). In each indoor heat exchanger (43a, 43b, 43c), the refrigerant absorbs heat from the indoor air and evaporates. Thereby, indoor air is cooled.

  The refrigerant evaporated in each indoor heat exchanger (43a, 43b, 43c) flows through each second branch pipe (54a, 54b, 54c) and joins in the low pressure gas pipe (14), and then the low-stage compressor ( 22) Inhaled and compressed.

  Even in such a cooling operation, it is possible to perform cooling with a part of the plurality of indoor units (40a, 40b, 40c), and heating with the rest. That is, for the BS unit (50c) corresponding to the indoor unit to be heated (for example, the indoor unit (40c)), the first on-off valve (55c) is opened, and the second on-off valve (56c) is closed. Thereby, a part of refrigerant discharged from the high-stage compressor (23) flows through the first branch pipe (53c) and then radiates heat in the indoor heat exchanger (43c). As a result, the indoor air can be heated with the refrigerant flowing through the indoor heat exchanger (43c), and at the same time, the indoor air can be cooled with the refrigerant flowing through the remaining indoor heat exchangers (43a, 43b).

<Second operation of cooling operation>
As shown in FIG. 10, in the second operation of the cooling operation, the composite valve (60) is in the third state (that is, the third angular position). Other than that is the same as the first operation of the cooling operation described above.

  In the second operation of the cooling operation, the refrigerant compressed by the low-stage compressor (22) and compressed to the intermediate pressure passes through the fourth port (94) and the sixth port (96), Flows through the diverter tube (54). This refrigerant is cooled by the outdoor air when passing through the intercooler (35). The cooled refrigerant is compressed to a high pressure by the high stage compressor (23). The subsequent operation is the same as the first operation of the cooling operation described above. In the second operation, the refrigerant compressed by the low-stage compressor (22) is cooled by the intercooler (35) and then further compressed by the high-stage compressor (23). Thereby, the compression power in the compression stroke of the high stage side compressor (23) can be reduced, and the energy-saving property of an air conditioning apparatus (10) can be improved.

-Switching operation of composite valve-
When each operation of the air conditioner described above is switched, the state of the composite valve (60) is switched in three stages. The switching operation of the composite valve (60) will be described in detail with reference to FIG. In addition, in FIG. 7, the internal channel | path of the communicating hole (87) which connects a 1st storage chamber (85) and a 2nd storage chamber (86) is typically represented by the dashed-dotted line.

<First angle position>
In the heating operation, when the composite valve (60) is in the first state, the first gate valve (111) and the second gate valve (121) are in the first angular position (see FIG. 7A). When the first gate valve (111) is at the first angular position, the first opening (91a) communicates with the first inner chamber (IS1), and the second opening (92a) and the third opening (93a) Communicates with the first outer chamber (OS2). As a result, the first port (91) is closed, and the second port (92) and the third port (93) communicate with each other. At the same time, when the second gate valve (121) is in the first angular position, the fourth opening (94a) and the fifth opening (95a) communicate with the second inner chamber (IS2), and the sixth opening (96a ) Communicates with the second outer chamber (OS2). As a result, the fourth port (94) and the fifth port (95) communicate with each other, and the sixth port (96) is closed. As described above, the refrigeration cycle of the heating operation described above can be executed by setting the communication state of each port (91 to 96).

  Thus, when the composite valve (60) is in the first state, the first inner chamber (IS1) communicates with the high-pressure line (high-pressure branch pipe (36)) via the first port (91). Thereby, the internal pressure of the first inner chamber (IS1) becomes equal to the pressure of the high-pressure refrigerant in the refrigerant circuit (11). On the other hand, the first outer chamber (OS1) communicates with the low pressure line (low pressure branch pipe (37)) via the second port (92). Thereby, the internal pressure of the first outer chamber (OS1) becomes equal to the pressure of the low-pressure refrigerant in the refrigerant circuit (11).

  When the composite valve (60) is in the first state, the second inner chamber (IS2) is connected to the discharge line (low-stage discharge pipe (low-stage discharge pipe ( 27)). Thereby, the internal pressure of the second inner chamber (IS2) becomes equal to the pressure of the intermediate pressure refrigerant in the refrigerant circuit (11). On the other hand, the second outer chamber (OS2) communicates with the second outer chamber (OS2) through a communication hole (87) formed in the intermediate plate (84). Thereby, the internal pressure of the second outer chamber (OS2) becomes equal to the internal pressure of the first outer chamber (OS1) (that is, the pressure of the low-pressure refrigerant). The second outer chamber (OS2) in the low pressure state communicates with the second branch pipe (32) through the sixth port (96). However, since the second check pipe (34) is provided in the second branch pipe (32), the intermediate-pressure refrigerant on the high-stage suction pipe (28) side passes through the second branch pipe (32). It is prevented from flowing back to the second outer chamber (OS2) in a low pressure state via the via. Therefore, the first outer chamber (OS1) and the second outer chamber (OS2) can be maintained in a low pressure state.

  As described above, in the composite valve (60) in the first state, the internal pressure of the first inner chamber (OS1) is high while the internal pressure of the first outer chamber (OS1) is low. Further, in the composite valve (60) in the first state, the internal pressure of the second inner chamber (OS2) becomes an intermediate pressure while the internal pressure of the second outer chamber (OS2) becomes a low pressure.

<Second angular position>
In the first operation of the cooling operation, when the composite valve (60) is in the second state, the first gate valve (111) and the second gate valve (121) are in the second angular position (see FIG. 7B). ). When the first gate valve (111) is in the second angular position, the first opening (91a) and the second opening (92a) communicate with the first inner chamber (IS1), and the third opening (93a) Communicates with the first outer chamber (OS2). As a result, the first port (91) and the second port (92) communicate with each other and the third port (93) is closed. At the same time, when the second gate valve (121) is in the second angular position, the fourth opening (94a) and the fifth opening (95a) communicate with the second inner chamber (IS2), and the sixth opening (96a ) Communicates with the second outer chamber (OS2). As a result, the fourth port (94) and the fifth port (95) communicate with each other, and the sixth port (96) is closed. As described above, by setting the communication state of each port (91 to 96), the refrigeration cycle of the first operation of the cooling operation described above can be executed.

  Thus, even when the composite valve (60) is in the second state, the first inner chamber (IS1) communicates with the high-pressure branch pipe (36) via the first port (91), and the first outer The chamber (OS1) communicates with the low-pressure branch pipe (37) through the second port (92). The second inner chamber (IS2) communicates with the low-stage discharge pipe (27) through the fourth port (94), and the second outer chamber (OS2) communicates with the first through the communication hole (87). 1 Communicate with the outer chamber (OS1). Therefore, also in the composite valve (60) in the second state, the first outer chamber (OS1) and the second outer chamber (OS2) are maintained at a low pressure.

<Third angular position>
In the second operation of the cooling operation, when the composite valve (60) is in the third state, the first gate valve (111) and the second gate valve (121) are in the third angular position (see FIG. 7C). ). When the first gate valve (111) is in the third angular position, the first opening (91a) and the second opening (92a) communicate with the first inner chamber (IS1), and the third opening (93a) Communicates with the first outer chamber (OS2). As a result, the first port (91) and the second port (92) communicate with each other and the third port (93) is closed. At the same time, when the second gate valve (121) is in the second angular position, the fourth opening (94a) and the sixth opening (96a) communicate with the second inner chamber (IS2), and the fifth opening (95a ) Communicates with the second outer chamber (OS2). As a result, the fourth port (94) communicates with the sixth port (96), and the fifth port (95) is closed. As described above, the refrigeration cycle of the second operation of the cooling operation described above can be performed by setting the communication state of each port (91 to 96).

  Thus, even when the composite valve (60) is in the third state, the first inner chamber (IS1) communicates with the high-pressure branch pipe (36) via the first port (91), and the first outer The chamber (OS1) communicates with the low-pressure branch pipe (37) through the second port (92). The second inner chamber (IS2) communicates with the low-stage discharge pipe (27) through the fourth port (94), and the second outer chamber (OS2) communicates with the first through the communication hole (87). 1 Communicate with the outer chamber (OS1). The second outer chamber (OS2) communicates with the first branch pipe (31) via the fifth port (95), and the first check pipe (33) is connected to the first branch pipe (31). Is provided. Therefore, the intermediate pressure refrigerant on the high-stage suction pipe (28) side does not flow back to the second outer chamber (OS2). As described above, the first outer chamber (OS1) and the second outer chamber (OS2) are maintained at a low pressure.

-Effect of Embodiment 1-
In the first embodiment, the composite valve (60) is connected to the refrigerant circuit (11) of the air conditioner (10), and the communication states of the six ports (91 to 96, 131 to 136) of the composite valve (60) are switched. Thus, the first operation of the heating operation and the cooling operation described above and the second operation of the cooling operation are switched. Here, when the composite valve (60) is applied to the refrigerant circuit (11) in this way, the number of switching valves can be reduced by one compared to, for example, the two-way switching valve method of the reference example shown in FIG. And the number of ports can be reduced by two. Further, in the example shown in FIG. 17, it is necessary to provide piping for sealing each port and other piping, but in this embodiment, such piping is also unnecessary. Therefore, it is possible to simplify the refrigerant circuit (11) and the mechanism (refrigerant channel switching valve) for switching the refrigerant channel of the refrigerant circuit (11).

  In addition, since the composite valve (60) can rotate and drive the two gate valves (111, 121) simultaneously by one drive source (motor (71)), two drive sources are not required as in the reference example of FIG. . In addition, since the composite valve (60) is a system in which the two gate valves (111, 121) are electrically driven to rotate, even if there is no refrigerant differential pressure as in the reference example of FIG. 96, 131 to 136) can be easily switched. Furthermore, in the system of this embodiment, it is not always necessary to keep the energized state in order to maintain the communication state as in the reference example of FIG. That is, by stopping energization of the motor (71), the angular position of each partition (111, 121) can be maintained as it is, and energy saving is also excellent.

  Further, the composite valve (60) of the present embodiment has the first storage chamber (85) and the second storage chamber (86), and the first switching unit (110) and the second switching unit (120) in the axial direction. Since the structure is arranged in two stages, it is possible to avoid the composite valve (60) from being enlarged in the direction perpendicular to the axis. Furthermore, since the two partition portions (111, 121) are formed in an arc shape along the axis of the output shaft (74), the accommodation space in the radial direction of each partition portion (111, 121) is also reduced.

  Further, in the composite valve (60), the first outer chamber (OS1) and the second outer chamber (OS2) are always maintained at a low pressure even when the angular position of the partition (111, 121) is displaced into three states. . As a result, no differential pressure is generated in both outer chambers (OS1, OS2), so that refrigerant does not leak between the outer chambers (OS1, OS2) through the gap around the output shaft (74). . That is, for example, if one of the first outer chamber (OS1) and the second outer chamber (OS2) has a high pressure and the other has a low pressure, the refrigerant leaks from around the axis of the output shaft (74). A sealing mechanism is required. On the other hand, in this embodiment, both the outer chambers (OS1, OS2) have the same pressure atmosphere, so that such a sealing mechanism is not necessary. In the present embodiment, the first outer chamber (OS1) and the second outer chamber (OS2) are set to low pressure, but the outer chambers (OS1, OS2) of both may be set to high pressure.

<< Embodiment 2 of the Invention >>
The rotary valve (130) according to the second embodiment of the present invention is applied to the same air conditioner (10) as that of the first embodiment. On the other hand, the composite valve (130) according to the second embodiment is different in configuration from the composite valve (60) of the first embodiment.

<Connection position of rotary valve in refrigerant circuit>
As shown in FIG. 11, the rotary valve (130) of Embodiment 2 is connected to a refrigerant circuit (11) similar to that of Embodiment 1 above. The rotary valve (130) has a disc-shaped valve case part (140). First to sixth ports (131 to 136) are formed in the valve case part (140). The first port (131) is connected to the high-pressure branch pipe (36), and the second port (132) is connected to the low-pressure branch pipe (37). The third port (133) is connected to the gas side end of the outdoor heat exchanger (24). The fourth port (134) is connected to the low-stage discharge pipe (27) of the low-stage compressor (22). The fifth port (135) is connected to the inflow end of the first branch pipe (31). The sixth port (136) is connected to the inflow end of the second branch pipe (32). The rotary valve (130) constitutes a refrigerant flow path switching valve for switching the refrigerant flow path of the refrigerant circuit (11). Specifically, the rotary valve (130) is configured to switch from a first state to a third state. In the first state (the state shown in FIG. 11), the second port (132) and the third port (133) communicate with each other to close the first port (131), and at the same time, the fourth port (134) and the fifth port The sixth port (136) is closed by communicating with the port (135). In the second state (the state shown in FIG. 15), the first port (131) and the third port (133) communicate with each other and the second port (132) is closed, and at the same time, the fourth port (134) and the fifth port are closed. The sixth port (136) is closed by communicating with the port (135). In the third state (the state shown in FIG. 16), the first port (131) and the third port (133) communicate with each other and the second port (132) closes. The fifth port (135) is closed by communicating with the port (136).

<Rotary valve structure>
The detailed structure of the rotary valve (130) will be described with reference to FIGS. The rotary valve (130) includes the above-described valve case (140), a drive mechanism (145), and a valve body (150) as a switching mechanism.

  The valve case part (140) is formed in a flat cylindrical shape. The valve case part (140) has a case main body (141) whose one end in the axial direction is open, and a disk-shaped lid part (142) that closes the open part of the case main body (141). The six ports (131 to 136) described above penetrate through the peripheral wall (141a) of the case body (141) in the radial direction. These ports (131 to 136) are arranged at equal intervals in the circumferential direction. Specifically, these ports (131 to 136) are arranged at intervals of about 60 ° about the axis of the case body (141). The case body (141) and the lid (142) are coupled to each other by a plurality of screws (143). A storage chamber (144) in which the valve case portion (140) is stored is formed inside the case body (141).

  The drive mechanism (145) includes a drive unit (146) having a motor and a transmission gear, and an output shaft (147) that is rotationally driven by the drive unit (146). The output shaft (147) penetrates the valve case portion (140) in the axial direction, and is connected to the valve body (150) via a key, for example.

  The valve body (150) is formed in a flat disk shape and is accommodated in the accommodation chamber (144). The valve body (150) includes a valve body upper lid (151), a gasket (152), and a valve body (153). In the valve body (150), the valve body upper lid (151), the gasket (152), and the valve main body (153) are sequentially laminated in the axial direction and coupled. Specifically, the plurality of screws (154) are fastened with the gasket (152) sandwiched between the valve body upper lid (151) and the valve body (153), so that the valve body (150) Composed.

  The valve body (153) is configured by a disk-shaped switching unit that switches the communication state of the ports (131 to 136). The valve body (153) is formed with a valve body passage (160) capable of communicating with the above-described ports (131 to 136). Specifically, the valve body passage (160) has fourteen internal passages (first to fourteenth internal passages (C1 to C14)) extending in a radial direction at a portion near the outer periphery of the valve body (153). (See FIG. 13). The radially outer ends of the internal passages (C1 to C14) open to the outer peripheral surface of the valve body (153). An annular groove (155) is formed on the outer peripheral edge of each of these open ends, and an O-ring (156) and an annular packing (157) are fitted into each annular groove (155) (see FIG. 12). reference).

  Each of the internal passages (C1 to C14) is disposed so as to coincide with a plurality of virtual radial lines that pass through the axis of the valve body (150) and form approximately 20 ° with each other. Specifically, the first to tenth internal passages (C1 to C10) are arranged at equal intervals so as to form about 20 ° in the circumferential direction. The interval between the tenth internal passage (C10) and the eleventh internal passage (C11) is slightly larger so as to form about 40 °. The 11th to 14th internal passages (C11 to C14) are arranged at equal intervals so as to form about 20 ° in the circumferential direction.

  Further, first to fourth arc grooves (161 to 164) forming a part of the valve body passage (160) are formed on one end face (upper end face in FIG. 12) of the valve body (153) in the axial direction. Is formed. These arc grooves (161 to 164) are located on an imaginary circle having a predetermined radius with the axis of the valve body (150) as the center. The first arc groove (161) is formed over a range of about 60 ° in the circumferential direction, and communicates with the first to fourth internal passages (C11 to C14). The second arc groove (162) is formed over a range of about 60 ° in the circumferential direction, and communicates with the fifth to eighth internal passages (C5 to C8). The third arc groove (163) is formed over a range of about 80 ° in the circumferential direction, and communicates with the ninth to twelfth internal passages (C9 to C12). The fourth arc groove (164) is formed over a range of about 20 ° in the circumferential direction, and communicates with the thirteenth and fourteenth internal passages (C13, C14).

  Further, a communication groove (165) that forms a part of the valve body passage (160) is formed on the upper end surface of the valve body (153). The communication groove (165) is formed along the periphery of the output shaft (147), and communicates the first arc groove (161) and the fourth arc groove (164).

  In the gasket (152) described above, a plurality of opening holes (152a) are formed so as to correspond to the shapes of the grooves (161 to 165) of the valve body (153). In the assembled state of the valve body (150), the opening hole of the gasket (152) and the grooves (161 to 165) of the valve body (153) coincide with each other in the axial direction. That is, the gasket (152) constitutes a seal member that prohibits refrigerant leakage from the grooves (161 to 165) of the valve body (153).

  In the rotary valve (130) configured as described above, the valve body (150) is rotationally driven by the drive mechanism (145). Specifically, the valve body (150) is configured to be displaced over at least a range of the first angular position, the second angular position, and the third angular position.

  Specifically, when the valve body (150) is rotated about 20 ° counterclockwise from the first angular position shown in FIG. 13, the valve body (150) becomes the second angular position. Further, when the valve body (150) is rotated approximately 20 ° counterclockwise from the second angular position, the valve body (150) assumes the third angular position.

  In the first angular position, when the second port (132) and the third port (133) communicate with each other and the first port (131) closes, the fourth port (134) and the fifth port (135) The sixth port (136) is closed in communication (see FIG. 14). In the second angular position, the first port (131) and the third port (133) communicate with each other and the second port (132) closes, and at the same time, the fourth port (134) and the fifth port (135) The sixth port (136) is closed by communication (see FIG. 15). In the third angle position, the first port (131) and the third port (133) communicate with each other and the second port (132) is closed, and at the same time, the fourth port (134) and the sixth port (136) are connected. The fifth port (135) is closed in communication (see FIG. 16).

-Driving action-
In the air conditioner (10) of the second embodiment, the heating operation and the cooling operation are performed in the same manner as in the first embodiment. In the cooling operation, the first operation and the second operation are performed as in the first embodiment.

<Heating operation>
In the heating operation shown in FIG. 14, the first on-off valves (55a, 55b, 55c) are opened, and the second on-off valves (56a, 56b, 56c) are closed. Further, the indoor expansion valves (42a, 42b, 42c) are opened, and the opening degree of the outdoor expansion valve (25) is adjusted as appropriate.

  During the heating operation, the valve body (150) of the rotary valve (130) is in the first angular position. In this state, the first port (131) is closed by the outer peripheral surface of the valve body (150), and the second port (132) is connected to the fifth internal passage (C5), the second circular groove (162), and the eighth It communicates with the third port (133) via the internal passage (C8). In this state, the fourth port (134) includes the second internal passage (C2), the first circular groove (161), the communication groove (165), the fourth circular groove (164), and the fourteenth internal passage ( C6) communicates with the fifth port (135), and the sixth port (136) is closed by the outer peripheral surface of the valve body (150).

  In the heating operation, the refrigerant compressed to the intermediate pressure by the low-stage compressor (22) passes through the fourth port (134) and the fifth port (135) and is further pressurized by the high-stage compressor (23). Compressed to The high-pressure refrigerant radiates heat in each indoor heat exchanger (43a, 43b, 43c) and is used for heating. This refrigerant is depressurized by the outdoor expansion valve (25) and then evaporated by the outdoor heat exchanger (24). The evaporated refrigerant passes through the third port (133) and the second port (132), and is compressed by the low-stage compressor (22).

<First operation of cooling operation>
In the first operation of the cooling operation shown in FIG. 15, the first on-off valves (55a, 55b, 55c) are closed, and the second on-off valves (56a, 56b, 56c) are opened. Further, the outdoor expansion valve (25) is opened, and the opening degree of each indoor expansion valve (42a, 42b, 42c) is appropriately adjusted.

  During the first operation of the cooling operation, the valve body (150) of the rotary valve (130) is in the second angular position. In this state, the first port (131) communicates with the third port (133) via the eleventh internal passage (C11), the third circular groove (163), and the ninth internal passage (C9), and the second port The port (132) communicates with the sixth internal passage (C6). Here, the other internal passages (C5, C7, C8) communicating with the sixth internal passage (C6) are blocked by the inner peripheral surface of the valve case portion (140). Accordingly, the second port (132) is substantially closed. In this state, the fourth port (134) includes the third internal passage (C3), the first circular groove (161), the communication groove (165), the fourth circular groove (164), and the fourteenth internal passage ( C6) communicates with the fifth port (135), and the sixth port (136) is closed by the outer peripheral surface of the valve body (150).

  In the first operation of the cooling operation, the refrigerant compressed to the intermediate pressure by the low-stage compressor (22) passes through the fourth port (134) and the fifth port (135), and passes through the high-stage compressor (23 ) Is further compressed to a high pressure. The high-pressure refrigerant flows through the high-pressure branch pipe (36), passes through the first port (131) and the third port (133), and radiates heat in the outdoor heat exchanger (24). The radiated refrigerant is depressurized by the indoor expansion valves (42a, 42b, 42c) and then evaporated by the indoor heat exchangers (43a, 43b, 43c). The evaporated refrigerant joins in the low-pressure gas pipe (14), and is then compressed in the low-stage compressor (22).

<Second operation of cooling operation>
In the second operation of the cooling operation shown in FIG. 16, each first on-off valve (55a, 55b, 55c) is closed and each second on-off valve (56a, 56b, 56c) is opened, as in the first operation. It becomes. Further, the outdoor expansion valve (25) is opened, and the opening degree of each indoor expansion valve (42a, 42b, 42c) is appropriately adjusted.

  During the first operation of the cooling operation, the valve body (150) of the rotary valve (130) is in the third angular position. In this state, the first port (131) communicates with the third port (133) via the twelfth internal passage (C12), the third circular groove (163), and the tenth internal passage (C10), and the second port The port (132) communicates with the seventh internal passage (C7). Here, the other internal passages (C5, C6, C8) communicating with the seventh internal passage (C7) are closed by the inner peripheral surface of the valve case portion (140). Accordingly, the second port (132) is substantially closed. In this state, the fourth port (134) communicates with the sixth port (136) via the fourth internal passage (C4), the first circular groove (161), and the first internal passage (C1). The fifth port (135) is closed by the outer peripheral surface of the valve body (150).

  In the second operation of the cooling operation, the refrigerant compressed to the intermediate pressure by the low-stage compressor (22) passes through the fourth port (134) and the sixth port (136) and is cooled by the intercooler (35). Is done. The refrigerant cooled by the intercooler (35) is compressed to a high pressure by the high stage compressor (23). Thus, by cooling the intermediate pressure refrigerant, the compression power of the refrigerant in the high stage compressor (23) is reduced.

-Effect of Embodiment 2-
In the second embodiment, the rotary valve (130) is connected to the refrigerant circuit (11) of the air conditioner (10), and the communication states of the six ports (131 to 136) of the rotary valve (130) are switched. The first operation of the heating operation and the cooling operation described above and the second operation of the cooling operation are switched. Here, when the rotary valve (130) is applied to the refrigerant circuit (11) in this way, the number of switching valves can be reduced by one compared to the two-way switching valve system of the reference example shown in FIG. And the number of ports can be reduced by two. In the example shown in FIG. 17, it is necessary to provide a pipe for sealing each port and other pipes. However, in the second embodiment, such a pipe is not necessary. Therefore, it is possible to simplify the refrigerant circuit (11) and the mechanism (refrigerant channel switching valve) for switching the refrigerant channel of the refrigerant circuit (11).

  Moreover, in the said Embodiment 2, the valve case part (140) of a rotary valve (130) is made into a flat shape in an axial direction, and six ports (131-136) are connected to the outer peripheral surface of a valve case part (140). I am doing so. For this reason, the rotary valve (130) can be thinned in the axial direction.

<< Other Embodiments >>
In the first and second embodiments, the refrigerant flow switching valve (60, 130) is applied to a so-called cooling / heating free type air conditioner. However, a refrigerant circuit, a refrigeration apparatus, a water heater, or the like of another type of air conditioner is used. It can also be applied to other refrigerant circuits.

  Further, the refrigerant circuit (11) of the air conditioner (10) of each of the above embodiments is filled with carbon dioxide as a refrigerant, but other refrigerants are filled to perform a vapor compression refrigeration cycle. May be.

  As described above, the present invention is useful for the refrigerant flow path switching valve that switches the flow path of the refrigerant in the refrigerant circuit, and the air conditioner that includes the refrigerant flow path switching valve.

10 Air conditioner
11 Refrigerant circuit
22 Low stage compressor
24 Outdoor heat exchanger
26 Low stage suction pipe (low pressure line)
27 Low stage discharge pipe (discharge line)
29 High-stage discharge pipe (high pressure line)
31 First branch pipe (first branch)
32 Second branch pipe (second branch path)
43a, 43b.43c Indoor heat exchanger
60 Composite valve (refrigerant flow path switching valve)
70 Drive mechanism
74 Output shaft
80 Valve case (case)
85 First containment chamber
86 Second containment chamber
87 Communication hole (internal communication path)
91 1st port
92 Second port
93 3rd port
94 Port 4
95 5th port
96 6th port
100 switching mechanism
110 1st switching part
111 First gate valve (first partition)
120 2nd switching part
121 Second gate valve (second partition)
130 Rotary valve (refrigerant flow path switching valve)
131 1st port
132 2nd port
133 3rd port
134 4th port
135 5th port
136 6th port
140 Valve case (case)
144 Valve chamber
145 Drive mechanism
147 Output shaft
150 Disc (switching mechanism)
153 Valve body (disc switch)
OS1 first outer chamber
IS1 1st inside room
OS2 2nd outer chamber
IS2 Second inner chamber
C1-C14 internal passage

Claims (7)

A refrigerant flow path switching valve for switching a refrigerant flow path of a refrigerant circuit (11) in which a refrigeration cycle is performed,
A drive mechanism (70,145) having an output shaft (74,147);
A case portion (80,140) to which the first to sixth ports (91 to 96,131 to 136) are connected;
A switching mechanism (100, 150) for switching the communication state of the ports (91 to 96, 131 to 136) by being housed in the case portion (80, 140) and being rotationally driven by the output shaft (74, 147);
The switching mechanism (100, 150) has a first angular position for communicating the second port (92, 132) and the third port (93, 133) and for communicating the fourth port (94, 134) and the fifth port (95, 135);
A second angular position for communicating the first port (91,131) and the second port (92,132) and for communicating the fourth port (94,134) and the fifth port (95,135);
The first port (91,131) and the second port (92,132) communicate with each other and the fourth port (94,134) and the sixth port (96,136) communicate with each other at a third angular position. A refrigerant flow path switching valve characterized by comprising: In claim 1,
The case portion (80) is stacked in two stages in the axial direction of the output shaft (74), and has a cylindrical first storage chamber (85) and a second storage chamber (86) formed around the output shaft. ) And
The first to third ports (91 to 93) are connected to the first storage chamber (85);
The fourth to sixth ports (94 to 96) are connected to the second storage chamber (86);
The switching mechanism (100) is accommodated in the first to third ports (91 to 93) by being accommodated in the first accommodating chamber (85) and being rotationally driven by the output shaft (74). The first switching unit (110) for switching the ports and the fourth to sixth ports (94 to 96) housed in the second housing chamber (86) and driven to rotate by the output shaft (74). And a second switching part (120) for switching the communication state of the refrigerant flow path switching valve. In claim 2,
Each of the ports (91 to 96) is connected to the case portion (80) so as to open in the axial end surface of the corresponding storage chamber (85, 86),
The first switching portion (110) is formed in a substantially cylindrical shape extending across both axial ends of the first storage chamber (85), and the first storage chamber (85) is connected to a first inner chamber ( IS1) and a first partition (111) that divides into an outer first outer chamber (OS1),
The second switching portion (120) is formed in a substantially cylindrical shape extending across both axial ends of the second storage chamber (86), and the second storage chamber (86) is connected to a second inner chamber ( IS2) and a second partition (121) that divides into an outer second outer chamber (OS2),
One or both of the inner chamber (IS1, IS2) and the outer chamber (OS1, OS2) of each of the storage chambers (85, 86) is associated with each port (91 to 96) A refrigerant flow path switching valve comprising a communication path for switching the communication state of the open end of 96). In claim 3,
Each partition (111, 121) is formed in an arc shape along the circumference of the output shaft (74),
Refrigerant flow path switching characterized in that the open ends of the ports (91 to 96) are arranged around the axis of the output shaft (74) so as to straddle the rotation trajectory of the corresponding partition (111, 121). valve. In claim 3 or 4,
The case portion (80) is formed with an internal communication path (87) for communicating the first outer chamber and the second outer chamber (OS2) in the range from the first angular position to the third angular position. A refrigerant flow path switching valve characterized by comprising: In claim 1,
The case portion (140) forms one flat cylindrical storage chamber (144) around the output shaft (74),
The first to sixth ports (131 to 136) are connected to the one storage chamber (144);
The switching mechanism (100) is formed in a disc shape that is accommodated in the one accommodating chamber (144), and is rotationally driven by the output shaft (74) so that the ports (131 to 136) communicate with each other. A refrigerant flow path switching valve comprising a disk-shaped switching portion (153) having a plurality of internal passages (C1 to C14) for switching between the two. Low-stage compressor (22) and high-stage compressor (23) connected in parallel between the discharge side of the low-stage compressor (22) and the suction side of the high-stage compressor (23) First and second branch paths (31, 32), a cooling mechanism (35) connected to the second branch path (32), an outdoor heat exchanger (24), an indoor heat exchanger ( 43a, 43b, 43c) and a refrigerant flow switching valve (60, 130) according to any one of claims 1 to 6, comprising a refrigerant circuit (11) for performing a refrigeration cycle,
In the refrigerant flow switching valve (60, 130), the first port (91, 131) is connected to the high-pressure line (29) on the discharge side of the high stage compressor (23), and the second port (92, 132) , Connected to one end of the outdoor heat exchanger (24), and the third port (93, 133) is connected to the low-pressure line (26) on the suction side of the low-stage compressor (22), The port (94, 134) is connected to the discharge line (27) on the discharge side of the low-stage compressor (22), the fifth port (95, 135) is connected to the first branch (31), and An air conditioner characterized in that a sixth port (96,136) is connected to the second branch (32).

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