EP3517855B1

EP3517855B1 - Heat exchanger and refrigeration cycle device

Info

Publication number: EP3517855B1
Application number: EP16916807.7A
Authority: EP
Inventors: Komei NAKAJIMA; Kosuke Tanaka; Yasuhide Hayamaru; Akinori SAKABE
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2016-09-23
Filing date: 2016-09-23
Publication date: 2020-09-16
Anticipated expiration: 2036-09-23
Also published as: WO2018055740A9; JP6671491B2; EP3517855A4; EP3517855A1; WO2018055740A1; JPWO2018055740A1

Description

TECHNICAL FIELD

The present invention relates to a heat exchanger and a refrigeration cycle apparatus.

BACKGROUND ART

As an example of a refrigeration cycle apparatus, an air conditioner may be given. A typical air conditioner is provided with a compressor, a four-way valve, a condenser, an expansion valve, and an evaporator. These components communicate with each other through a connecting pipe to constitute a refrigeration cycle.
In this air conditioner, the refrigerant is switched by the four-way valve to flow reversely so as to switch between the heating operation mode and the cooling operation mode. In the heating operation mode, an indoor heat exchanger is used as a condenser, and an outdoor heat exchanger is used as an evaporator. In the cooling operation mode, the indoor heat exchanger is used as an evaporator, and the outdoor heat exchanger is used as a condenser.
Thus, in the cooling operation mode and the heating operation mode, the outdoor heat exchanger and the indoor heat exchanger works differently. In other words, the outdoor heat exchanger and the indoor heat exchanger each may be used as a condenser or an evaporator. The state of the refrigerant flowing through the heat exchanger is different between the condenser and the evaporator. In the case of a condenser, the refrigerant is supplied to an inlet port of the heat exchanger as a superheated gas, which is condensed to a two-phase gas-liquid by heat exchange, and is discharged as a supercooled liquid from an outlet port of the heat exchanger. On the other hand, in the case of an evaporator, the refrigerant is supplied to the inlet port of the heat exchanger as a liquid or a two-phase gas-liquid, which is gasified by heat exchange, and is discharged as a saturated gas from the outlet of the heat exchanger.
The flow rate of the refrigerant flowing through a heat transfer tube provided in the heat exchanger varies depending on whether the refrigerant is in a liquid state or in a gas state. The performance of the heat exchanger changes depending on the flow rate of the refrigerant.
In order to optimize the flow rate of refrigerant so as to maximize the performance of the heat exchanger, it is required to adjust the number of the refrigerant flow paths (path number) or the length thereof in the outdoor heat exchanger. However, in a typical air conditioner in a prior art, the number or length of the refrigerant flow paths is fixed in both the cooling operation mode and the heating operation mode. Generally, the typical air conditioner is designed to work with optimum performance in one mode of the cooling operation mode and the heating operation mode, and thereby, the typical air conditioner may work with a lower performance in the other mode of the cooling operation mode and the heating operation mode.
Japanese Patent Laying-open No. 2015-117936 (PTL 1) describes an air conditioner to solve the problem mentioned above. In the air conditioner described in PTL 1, two flow path units are connected in series in the cooling operation mode, and connected in parallel in the heating operation mode. In addition, the two flow-path units in the outdoor heat exchanger are switched to series connection or parallel connection by using three valves. JP2012-77921 A discloses a refrigeration apparatus of which the heat source side heat exchanger includes a main heat exchanger unit and an auxiliary heat exchanger unit. A four-way switching valve is provided to set the heat source side heat exchanger in serial connection during cooling operation to direct the refrigerant through the main heat exchanger unit for condensation and subsequently through the auxiliary heat exchanger unit for subcooling. The four way valve is configured to set the heat source side heat exchanger in parallel connection during heating operation to direct part of the refrigerant through the main heat exchanger unit and the other part of the refrigerant through the auxiliary heat exchanger unit for evaporation.

CITATION LIST

PATENT LITERATURE

PTL 1: Japanese Patent Laying-open No. 2015-117936

SUMMARY OF INVENTION

TECHNICAL PROBLEM

However, in the air conditioner described in PTL 1, the number of the two flow path units is equal. In other words, the heat exchanger is equally divided between the two flow path units. Therefore, the number of refrigerant flow paths (path number) will become more at a location where there is more liquid phase in the refrigerant, whereby the flow rate of the refrigerant will become slow. Therefore, if the air conditioner is used for example as a condenser, there will be more liquid phase present in the refrigerant in one flow path unit located downstream, and thereby the heat transfer performance of this flow path unit will be deteriorated. As a result, the performance of the heat exchanger will be deteriorated.
In the air conditioner described in PTL 1, the outdoor heat exchanger is provided with three valves so as to switch the two flow path units to series connection or parallel connection, which makes it difficult to downsize the heat exchanger.
The present invention has been made in view of the above problems, and an object thereof is to provide a heat exchanger with improved performance and a smaller size, and a refrigeration cycle apparatus including the heat exchanger.

SOLUTION TO PROBLEM

The heat exchanger of the present invention includes a first heat exchanger unit, a second heat exchanger unit, and a switching valve. The first heat exchanger unit includes a plurality of first refrigerant flow paths, a first connection port in fluid communication with the plurality of first refrigerant flow paths, and a second connection port provided on the side opposite to the first connection port and configured to be in fluid communication with the plurality of first refrigerant flow paths. The second heat exchanger unit includes at least one second refrigerant flow path, a third connection port in fluid communication with the second refrigerant flow path, and a fourth connection port provided on the side opposite to the third connection port and configured to be in fluid communication with the second refrigerant flow path. The switching valve includes a first inlet/outlet port, a second inlet/outlet port, a third inlet/outlet port, a fourth inlet/outlet port, a first valve flow path, a second valve flow path, and a third valve flow path. The first inlet/outlet port is connected to the first connection port. The second inlet/outlet port is connected to the third connection port. The third inlet/outlet port is connected to the second connection port. The fourth inlet/outlet port is connected to the fourth connection port. The first valve flow path is configured to fluidly communicate the first inlet/outlet port with the second inlet/outlet port. The second valve flow path is configured to fluidly communicate the second inlet/outlet port with the third inlet/outlet port. The third valve flow path is configured to fluidly communicate the third inlet/outlet port with the fourth inlet/outlet port. The number of the plurality of first refrigerant flow paths in the first heat exchanger unit is configured to be greater than the number of the at least one second refrigerant flow path in the second heat exchanger unit. The switching valve is configured to close the first valve flow path and the third valve flow path but open the second valve flow path or to open the first valve flow path and the third valve flow path but close the second valve flow path.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the heat exchanger of the present invention, the number of the plurality of first refrigerant flow paths in the first heat exchanger unit is greater than the number of the at least one second refrigerant flow path in the second heat exchanger unit. Therefore, if the second heat exchanger unit is operated at a location where there is more liquid phase present in the refrigerant, it is possible to reduce the number of the refrigerant flow paths at the location where there is more liquid phase present in the refrigerant so as to increase the flow rate of the refrigerant. Therefore, it is possible to improve the heat transfer performance at a location where there is more liquid phase present in the refrigerant, which makes it possible to improve the performance of the heat exchanger. Moreover, the switching valve is configured to close the first valve flow path and the third valve flow path but open the second valve flow path or to open the first valve flow path and the third valve flow path but close the second valve flow path. Therefore, it is possible to switch the first heat exchanger unit and the second heat exchanger unit to series connection or parallel connection with one switching valve, which makes it possible to downsize the heat exchanger.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 is a structural view illustrating a refrigeration cycle of a refrigeration cycle apparatus in a cooling operation mode according to a first embodiment of the present invention;
Fig. 2 is a structural view illustrating a refrigeration cycle of the refrigeration cycle apparatus in a heating operation mode according to the first embodiment of the present invention;
Fig. 3 is an enlarged view of an outdoor heat exchanger illustrated in Fig. 1;
Fig. 4 is an enlarged view of an outdoor heat exchanger illustrated in Fig. 2;
Fig. 5 is a structural view illustrating the refrigeration cycle of a refrigeration cycle apparatus when zeotropic refrigerant is used according to the first embodiment of the present invention;
Fig. 6 is a structural view illustrating a refrigeration cycle of a refrigeration cycle apparatus in a cooling operation mode according to a second embodiment of the present invention;
Fig. 7 is a structural view illustrating the refrigeration cycle of the refrigeration cycle apparatus in a heating operation mode according to a second embodiment of the present invention;
Fig. 8 is a structural view illustrating a refrigeration cycle of a refrigeration cycle apparatus in a cooling operation mode according to a third embodiment of the present invention;
Fig. 9 is a structural view illustrating a heat exchanger used as a condenser in a refrigeration cycle apparatus according to a fourth embodiment of the present invention; and
Fig. 10 is a structural view illustrating a heat exchanger used as an evaporator in the refrigeration cycle apparatus according to the fourth embodiment of the present invention.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the embodiments of the present invention, an air conditioner will be given as an example of a refrigeration cycle apparatus, and the description will be carried out on the air conditioner. However, the refrigeration cycle apparatus is not limited to an air conditioner, it may be a refrigeration apparatus, a chilling machine or the like.

First Embodiment

With reference to Figs. 1 and 2, the configuration of an air conditioner according to a first embodiment of the present invention will be described. Fig. 1 is a structural view illustrating a refrigeration cycle of an air conditioner in a cooling operation mode according to a first embodiment of the present invention, and Fig. 2 is a structural view illustrating a refrigeration cycle of the air conditioner in a heating operation mode according to the first embodiment of the present invention.
The air conditioner (refrigeration cycle apparatus) according to the first embodiment includes a compressor 1, a four-way valve 2, an outdoor heat exchanger 3 (a first outdoor heat exchanger 3a, a second outdoor heat exchanger 3b, and a switching valve 4), an expansion valve 5 (a first expansion valve 5a and a second expansion valve 5b), and an indoor heat exchanger 6.
The compressor 1, the four-way valve 2, the outdoor heat exchanger 3 (the first outdoor heat exchanger 3a, the second outdoor heat exchanger 3b, and the switching valve 4), the expansion valve 5 and the indoor heat exchanger 6 are configured to communicate with each other through pipes to constitute a refrigeration cycle (refrigerant circuit).
Refrigerant is configured to flow in the refrigeration cycle. In other words, the refrigerant flows through the compressor 1, the four-way valve 2, the first outdoor heat exchanger (first heat exchanger unit) 3a, the second outdoor heat exchanger (second heat exchanger unit) 3b, the switching valve 4, the first expansion valve 5a, the second expansion valve 5b, and the indoor heat exchanger 6. As the refrigerant flowing through the refrigerant cycle, a single-component refrigerant or an azeotropic refrigerant may be used. For example, R32 may be used as an example of a single-component refrigerant, and R410 may be used an example of an azeotropic refrigerant In addition, a zeotropic refrigerant may be used as the refrigerant. For example, R1234yf may be used as an example of a zeotropic refrigerant.
The air conditioner is further provided with a control device (controller) (not shown). The control device (controller) is configured to perform computation, issue instruction and the like so as to control each means or device in the refrigeration cycle device. Specifically, the control device (controller) is configured to control the operations of the four-way valve 2 and the switching valve 4, for example.
In Fig. 1, the compressor 1, the four-way valve 2, the outdoor heat exchanger 3 (the first outdoor heat exchanger 3a, the second outdoor heat exchanger 3b, and the switching valve 4), the expansion valve 5 (the first expansion valve 5a and the second expansion valve 5b) are provided in an outdoor unit (not shown). The indoor heat exchanger 6 is provided in an indoor unit (not shown).
The compressor 1 is configured to compress sucked refrigerant and discharge the compressed refrigerant. The compressor 1 may be a constant-speed compressor whose compression capacity is constant or an inverter compressor whose compression capacity is variable. This inverter compressor is configured to have a variable number of rotations. Specifically, the inverter compressor is configured to adjust the number of rotations by changing the driving frequency based on an instruction from the control device (controller, not shown), and thereby changing the compression capacity. The compression capacity represents a discharged amount of refrigerant per unit time.
The four-way valve 2 is connected to the compressor 1, the outdoor heat exchanger 3, and the indoor heat exchanger 6. The four-way valve 2 is configured to switch the flow of refrigerant to the outdoor heat exchanger 3 and the indoor heat exchanger 6 based on the cooling operation mode and the heating operation mode.
The outdoor heat exchanger 3 is connected to the four-way valve 2 and the expansion valve 5. In the cooling operation mode, the outdoor heat exchanger 3 functions as a condenser that condenses the refrigerant compressed by the compressor 1. On the other hand, in the heating operation mode, the outdoor heat exchanger 3 functions as an evaporator that evaporates the refrigerant decompressed by the expansion valve 5 (throttle device). The outdoor heat exchanger (heat exchanger) 3 includes the first outdoor heat exchanger (first heat exchanger unit) 3a, the second outdoor heat exchanger (second heat exchanger unit) 3b, and the switching valve 4, The first outdoor heat exchanger 3a is connected to the four-way valve 2 and the switching valve 4. The second outdoor heat exchanger 3b is connected to the switching valve 4 and the first expansion valve 5a. The outdoor heat exchanger 3 is configured to perform heat exchange between the refrigerant and air. The outdoor heat exchanger 3 is constituted by, for example, a pipe (heat transfer tube) and a fin member.
The switching valve 4 is connected to the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b. The switching valve 4 is configured to switch the flow path for the refrigerant flowing through the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b.
The expansion valve 5 is connected to the outdoor heat exchanger 3 and the indoor heat exchanger 6. In the cooling operation mode, the expansion valve 5 functions as a throttle device that decompresses the refrigerant condensed by the outdoor heat exchanger (condenser) 3. On the other hand, in the heating operation mode, the expansion valve 5 functions as a throttle device that decompresses the refrigerant condensed by the indoor heat exchanger (condenser) 6. The expansion valve 5 includes a first expansion valve 5a and a second expansion valve 5b, The first expansion valve 5a is connected to the second outdoor heat exchanger 3b and the indoor heat exchanger 6. The first expansion valve 5a is configured to expand (decompress) the refrigerant by adjusting the valve opening degree. The first expansion valve 5a may be, for example, an electronic expansion valve.
The second expansion valve 5b is connected between the four-way valve 2 and a location between the first expansion valve 5a and the indoor heat exchanger 6. The second expansion valve 5b is configured to expand (decompress) the refrigerant by adjust the valve opening degree. The second expansion valve 5b is configured to close the refrigerant circuit by closing the valve. The second expansion valve 5b may be, for example, an electronic expansion valve.
In the first embodiment, two expansion valves, namely the first expansion valve 5a and the second expansion valve 5b are provided. Accordingly, when the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b are used as an evaporator, the amount of refrigerant circulating in each flow path may be made equal by adjusting the amount of refrigerant circulating in the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b. When adjusting the amount of refrigerant under circulation, the expansion valve connected to the second outdoor heat exchanger 3b is regulated to have a smaller opening degree than the expansion valve connected to the first outdoor heat exchanger 3a.
The indoor heat exchanger 6 is connected to the first expansion valve 5a and the four-way valve 2. In the cooling operation mode, the indoor heat exchanger 6 functions as an evaporator that evaporates the refrigerant decompressed by the throttle device. On the other hand, in the heating operation mode, the indoor heat exchanger 6 functions as a condenser that condenses the refrigerant compressed by the compressor 1. The indoor heat exchanger 6 is configured to perform heat exchange between the refrigerant and air. The indoor heat exchanger 6 is constituted by, for example, a pipe (heat transfer tube) and a fin member.
In the first embodiment, the description will be carried out on the case where the number of the refrigerant flow paths (path number) in the outdoor heat exchanger 3 is variable. However, it is acceptable that the number of the refrigerant flow paths (path number) in the indoor heat exchanger 6 is variable or the number of the refrigerant flow paths (path number) in both the outdoor heat exchanger 3 and the indoor heat exchanger 6 is variable. In other words, the heat exchanger of the present embodiment may be at least one of a condenser and an evaporator.
Next, with reference to Figs. 3 and 4, the configuration of the outdoor heat exchanger (heat exchanger) 3 according to the first embodiment of the present invention will be described in detail. Fig. 3 is a structural view illustrating the outdoor heat exchanger 3 according to the first embodiment of the present invention in the cooling operation mode, and Fig. 4 is a structural view illustrating the outdoor heat exchanger 3 according to the first embodiment of the present invention in the heating operation mode.
The first outdoor heat exchanger (first heat exchanger unit) 3a is provided with a plurality of first refrigerant flow paths RF1, a first connection port C1, and a second connection port C2. In the cooling operation mode, the first connection port C1 serves as a refrigerant inlet, and the second connection port C2 serves as a refrigerant outlet. In the heating operation mode, the first connection port C1 serves as the refrigerant outlet, and the second connection port C2 serves as the refrigerant inlet. The first connection port C1 is in fluid communication with the first refrigerant flow path RF1. The second connection port C2 is provided on the side opposite to the first connection port C1 and configured to be in fluid communication with the first refrigerant flow path RF1. The plurality of first refrigerant flow paths RF1 are in fluid communication with the first connection port C1 and the second connection port C2 via a header (not shown).
The second outdoor heat exchanger (second heat exchanger unit) 3b is provided with at least one second refrigerant flow path RF2, a third connection port C3, and a fourth connection port C4. In the cooling operation mode, the third connection port C3 serves as a refrigerant inlet, and the fourth connection port C4 serves as a refrigerant outlet. In the heating operation mode, the third connection port C3 serves as the refrigerant outlet, and the fourth connection port C4 serves as the refrigerant inlet. The third connection port C3 is in fluid communication with the second refrigerant flow path RF2. The fourth connection port C4 is provided on the side opposite to the third connection port C3 and configured to be in fluid communication with the second refrigerant flow path RF2. At least one second refrigerant flow path RF2 is in fluid communication with the third connection port C3 and the fourth connection port C4 via a header (not shown).
The number of the plurality of first refrigerant flow paths RF1 in the first outdoor heat exchanger (first heat exchanger unit) 3a is greater than the number of the at least one second refrigerant flow path RF2 in the second outdoor heat exchanger (second heat exchanger unit) 3b. In the present embodiment, the number (path number) of the plurality of first refrigerant flow paths RF1 is, for example, 4, while the number (path number) of the at least one second refrigerant flow path RF2 is, for example, 2. The path number refers to the number of refrigerant flow paths divided for the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b, respectively.
The switching valve 4 includes a first inlet/outlet port P1, a second inlet/outlet port P2, a third inlet/outlet port P3, a fourth inlet/outlet port P4, a first valve flow path VF1, a second valve flow path VF2, a third valve flow path VF3, a main body 10, a shaft 11, a first valve seat 12a, a second valve seat 12b, a third valve seat 12c, a first valve 13a, a second valve 13b, a third valve 13c, and a drive unit 14.
The main body 10 of the switching valve 4 is provided with a total of 4 ports for the refrigerant to flow in or out. The first inlet/outlet port P1 of the switching valve 4 is connected to the first connection port C1 of the first outdoor heat exchanger 3a. The second inlet/outlet port P2 of the switching valve 4 is connected to the third connection port C3 of the second outdoor heat exchanger 3b. The third inlet/outlet port P3 of the switching valve 4 is connected to the second connection port C2 of the first outdoor heat exchanger 3a. The fourth inlet/outlet port P4 of the switching valve 4 is connected to the fourth connection port C4 of the second outdoor heat exchanger 3b.
Therefore, as illustrated in Fig. 3, the first inlet/outlet port P1 is connected to the refrigerant inlet side of the first outdoor heat exchanger 3a in the cooling operation mode. The second inlet/outlet port P2 is connected to the refrigerant inlet side of the second outdoor heat exchanger 3b in the cooling operation mode. The third inlet/outlet port P3 is connected to the refrigerant outlet side of the first outdoor heat exchanger 3a in the cooling operation mode. The fourth inlet/outlet port P4 is connected to the refrigerant outlet side of the second outdoor heat exchanger 3b in the cooling operation mode.
Further, as illustrated in Fig. 4, the first inlet/outlet port P1 is connected to the refrigerant outlet side of the first outdoor heat exchanger 3a in the heating operation mode. The second inlet/outlet port P2 is connected to the refrigerant outlet side of the second outdoor heat exchanger 3b in the heating operation mode. The third inlet/outlet port P3 is connected to the refrigerant inlet side of the first outdoor heat exchanger 3a in the heating operation mode. The fourth inlet/outlet port P4 is connected to the refrigerant inlet side of the second outdoor heat exchanger 3b in the cooling operation mode.
The main body 10 of the switching valve 4 is configured to have a cylinder shape, and the first valve flow path VF1, the second valve flow path VF2 and the third valve flow path VF3 are provided inside the main body 10 of the switching valve 4.
The first valve flow path VF1 fluidly communicates the first inlet/outlet port P1 with the second inlet/outlet port P2. The first valve seat 12a is disposed in the first valve flow path VF1. The first valve seat 12a is disposed between the first inlet/outlet port P1 and the second inlet/outlet port P2. The first valve 13a is configured to close the first valve flow path VF1 by coming into contact with the first valve seat 12a and to open the first valve flow path VF1 by leaving away from the first valve seat 12a.
The second valve flow path VF2 fluidly communicates the second inlet/outlet port P2 with the third inlet/outlet port P3. The second valve seat 12b is disposed in the second valve flow path VF2. The second valve seat 12b is disposed between the second inlet/outlet port P2 and the third inlet/outlet port P3. The second valve 13b is configured to close the second valve flow path VF2 by coming into contact with the second valve seat 12b and to open the second valve flow path VF2 by leaving away from the second valve seat 12b.
The third valve flow path VF3 fluidly communicates the third inlet/outlet port P3 with the fourth inlet/outlet port P4. The third valve seat 12c is disposed in the third valve flow path VF3. The third valve seat 12c is disposed between the third inlet/outlet port P3 and the fourth inlet/outlet port P4. The third valve 13c is configured to close the third valve flow path VF3 by coming into contact with the third valve seat 12c and to open the third valve flow path VF3 by leaving away from the third valve seat 12c.
The first valve 13a, the second valve 13b and the third valve 13c are attached to the shaft 11. Each of the first valve 13a, the second valve 13b, and the third valve 13c has a flat plate shape. The first valve 13a, the second valve 13b and the third valve 13c may be attached to the shaft 11 in such a manner that the shaft 11 penetrates through the center of each flat plate-shaped valve. The first valve 13a, the second valve 13b and the third valve 13c are disposed apart from each other in the axial direction of the shaft 11.
In this way, since the switching valve 4 is configured to have one shaft, it is possible to perform the flow path switching simultaneously. In the heating operation mode, the outdoor heat exchanger 3 may have frost formed thereon, whereby it is necessary to perform a defrosting operation. In the defrosting operation, the four-way valve 2 is switched from the refrigerant circuit in the heating operation mode to the refrigerant circuit in the cooling operation mode so as to remove the frost. When switching the refrigerant circuit so as to perform the defrosting operation, the flow path may be switched immediately,
The drive unit 14 is configured to drive the shaft 11 in the axial direction. The drive unit 14 includes a movable member 14a and a coil 14b. The movable member 14a is attached to the shaft 11. The coil 14b is arranged to surround the movable member 14a. The movable member 14a is configured to be moved in the axial direction of the shaft 11 by a magnetic flux generated by energizing the coil 14b based on an instruction from a control device (controller) (not shown). Therefore, the first valve 13a, the second valve 13b and the third valve 13c are movable in the axial direction of the shaft 11 along with the movement of the movable member 14a.
Since the switching valve 4 is configured to have one shaft, only one drive unit 14 is sufficient. Specifically, the switching valve 4 may be formed with one movable member 14a and one coil 14b in the drive unit 14, which makes it possible to reduce the cost.
The switching valve 4 is configured to close the first valve flow path VF1 and the third valve flow path VF3 but open the second valve flow path VF2 or to open the first valve flow path VF1 and the third valve flow path VF3 but close the second valve flow path VF2. By closing the first valve flow path VF1 and the third valve flow path VF3 but opening the second valve flow path VF2, the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b are connected in series. On the other hand, by opening the first valve flow path VF1 and the third valve flow path VF3 but closing the second valve flow path VF2, the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b are connected in parallel. In this way, it is possible for the switching valve 4 to switch the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b to series connection or parallel connection.
The second valve flow path VF2 is sandwiched between the first valve flow path VF1 and the third valve flow path VF3. Thus, when the second valve flow path VF2 arranged in a middle portion of the switching valve 4 is opened, the first valve flow path VF1 arranged above the second valve flow path VF2 and the third valve flow path VF3 arranged below the second valve flow path VF2 are closed. On the other hand, when the second valve flow path VF2 arranged in a middle portion of the switching valve 4 is closed, the first valve flow path VF1 arranged above the second valve flow path VF2 and the third valve flow path VF3 arranged below the second valve flow path VF2 are opened.
Next, with reference to Figs. 1 and 3, the flow of the refrigerant in the refrigeration cycle in the cooling operation mode according to the first embodiment will be described. The high temperature and high pressure gas refrigerant discharged from the compressor 1 flows into the four-way valve 2. In the cooling operation mode, the four-way valve 2 is set to guide the refrigerant into the outdoor heat exchanger 3. In the outdoor heat exchanger 3, the high pressure and high temperature gas refrigerant exchanges heat with air, whereby it is condensed to liquid refrigerant. Meanwhile, the air passing through the outdoor heat exchanger 3 is heated.
After the refrigerant has passed through the first outdoor heat exchanger 3a, the switching valve 4 is set to guide the refrigerant into the second outdoor heat exchanger 3b. Specifically, the refrigerant flowing into the first outdoor heat exchanger 3a from the first connection port C1 is condensed in the plurality of first refrigerant flow paths RF1 of the first outdoor heat exchanger 3a. The condensed refrigerant flows out from the second connection port C2, and then flows into the switching valve 4 through the third inlet/outlet port P3. At this time, the second valve flow path VF2 is opened by moving the second valve 13b away from the second valve seat 12b. Therefore, the refrigerant flows out of the second inlet/outlet port P2 through the second valve flow path VF2. The refrigerant flowing out from the second inlet/outlet port P2 flows into the second outdoor heat exchanger 3b through the third connection port C3. The refrigerant flowing into the second outdoor heat exchanger 3b is condensed in at least one second refrigerant flow path RF2 of the second outdoor heat exchanger 3b.
At this time, since the first valve 13a is brought into contact with the first valve seat 12a, the first valve flow path VF1 is closed. Therefore, the refrigerant flowing into the first inlet/outlet port P1 of the switching valve 4 will not flow into the second inlet/outlet port P2 through the first valve flow path VF1. Meanwhile, since the third valve 13c is brought into contact with the third valve seat 12c, the third valve flow path VF3 is closed. Therefore, the refrigerant flowing in the third valve flow path VF3 from the third inlet/outlet port P3 of the switching valve 4 will not flow into the fourth inlet/outlet port P4.
The refrigerant, which has been condensed to the liquid phase in the second refrigerant flow path RF2, flows into the first expansion valve 5a, and is throttled by the first expansion valve 5a into a low pressure and low temperature two-phase gas-liquid refrigerant. The low temperature and low pressure refrigerant flows into the indoor heat exchanger 6 to exchange heat with air. At this time, the air passing through the indoor heat exchanger 6 is refrigerated, and the two-phase gas-liquid refrigerant is heated by the surrounding air and is turned into gas phase. Thereafter, the gas refrigerant flows through the four-way valve 2 into the compressor 1. The compressor 1 compresses the sucked refrigerant and discharges the compressed refrigerant again. In other words, in the cooling operation mode, the refrigerant circulates in the refrigeration cycle as indicated by solid arrows in Fig. 1.
In the cooling operation mode, the flow path is set so as to open the second valve flow path VF2 arranged in the middle portion. By setting the flow path as described above, after the refrigerant passes through the first outdoor heat exchanger 3a, it flows into the second outdoor heat exchanger 3b. Since the path number of the second outdoor heat exchanger 3b is smaller than that of the first outdoor heat exchanger 3a, even if the refrigerant is condensed and has more liquid phase, it may flow through the second outdoor heat exchanger 3b at a greater flow speed. Therefore, it is possible to improve the heat transfer rate of the heat transfer pipe, and as a result, the performance of the heat exchanger may be improved.
Subsequently, with reference to Figs. 2 and 4, the flow of the refrigerant in the refrigeration cycle in the heating operation mode according to the first embodiment will be described. The high temperature and high pressure gas refrigerant discharged from the compressor 1 flows into the four-way valve 2. In the heating operation mode, the four-way valve 2 is set to guide the refrigerant into the indoor heat exchanger 6. In the indoor heat exchanger 6, the high pressure and high temperature gas refrigerant exchanges heat with air, whereby it is condensed to liquid refrigerant. Meanwhile, the air passing through the indoor heat exchanger 6 is heated.
Next, the refrigerant flows into the first expansion valve 5a and the second expansion valve 5b where it is turned into a low pressure and low temperature refrigerant. Thereafter, when guiding the refrigerant into the outdoor heat exchanger 3, the switching valve 4 is set to guide the refrigerant into the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b in parallel. Specifically, the refrigerant flowing into the second outdoor heat exchanger 3b from the fourth connection port C4 through the first expansion valve 5a exchanges heat with air in the at least one second refrigerant flow path RF2 of the second outdoor heat exchanger 3b, whereby it is turned into a low pressure and low temperature gas refrigerant. The low temperature and low pressure gas refrigerant flows out from the third connection port C3 and flows into the switching valve 4 through the second inlet/outlet port P2. At this time, since the first valve 13a is moved away from the first valve seat 12a, the first valve flow path VF1 is opened. Therefore, the refrigerant flows out from the first inlet/outlet port P1 through the first valve flow path VF1. After the refrigerant flows out from the first inlet/outlet P1, it flows into the four-way valve 2.
After passing through the second expansion valve 5b, the refrigerant flows into the switching valve 4 through the fourth inlet/outlet port P4. At this time, since the third valve element 13c is moved from the third valve seat 12c, the third valve flow path VF3 is opened. Therefore, the refrigerant flows out of the third inlet/outlet port P3 through the third valve flow path VF3, and flows into the first outdoor heat exchanger 3a through the second connection port C2. The refrigerant flowing into the first outdoor heat exchanger 3a through the second connection port C2 exchanges heat with air in the plurality of first refrigerant flow paths RF1 of the first outdoor heat exchanger 3a, whereby it is turned into a low pressure and low temperature gas refrigerant. The low temperature and low pressure gas refrigerant flows out from the first connection port C1 into the four-way valve 2.
At this time, since the second valve 13b is brought into contact with the second valve seat 12b, the second valve flow path VF2 is closed. Therefore, the refrigerant flowing from the second outdoor heat exchanger 3b into the second inlet/outlet port P2 of the switching valve 4 will not flow into the third inlet/outlet port P3 through the second valve flow path VF2, and meanwhile the refrigerant flowing through the second expansion valve 5b into the fourth inlet/outlet port P4 of the switching valve 4 will not flow into the second inlet/outlet port P2 through the second valve-inside flow path VF2.
Thereafter, the refrigerant flows through the four-way valve 2 into the compressor 1. The compressor 1 compresses the sucked refrigerant and discharges the compressed refrigerant again. In other words, in the heating operation mode, the refrigerant circulates in the refrigeration cycle as indicated by solid arrows in Fig. 2.
In the heating operation mode, the flow path is set such that the second valve flow path VF2 arranged in the middle portion is closed while the first valve flow path VF1 arranged above the second valve flow path VF2 and the third valve flow path VF3 arranged below the second valve flow path VF2 are opened. By setting the flow path as described above, the refrigerant flows through the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b in parallel. When the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b are used as the evaporator, the two-phase gas-liquid refrigerant flows through the heat exchangers in parallel, and thus, the pressure loss is small and the heat transfer rate is also ensured. Thereby, it is possible to improve the performance of the heat exchanger.
When connecting the second outdoor heat exchanger 3b to the switching valve 4, the refrigerant inlet of the second outdoor heat exchanger 3b is connected to the switching valve 4 at the air suction side of the outdoor heat exchanger 3. This is because when the outdoor heat exchanger 3 is used as a condenser and a refrigerant with smaller pressure loss, for example, an azeotropic refrigerant such as R410a or a single-component refrigerant such as R32 is used, the outdoor heat exchanger 3 may use the counter current to improve the performance of the heat exchanger. On the other hand, when the outdoor heat exchanger is used as a condenser and a zeotropic refrigerant such as R1234yf is used, with reference to Fig. 5, the refrigerant inlet of the second outdoor heat exchanger 3b is provided at the upwind side. This is because when a zeotropic refrigerant is used, the pressure loss is greater even at a high pressure. Thus, when the outdoor heat exchanger 3 is used as a condenser, it is easy to control the supercooling degree, which makes it possible to improve the performance of the heat exchanger.
Next, the effects of the first embodiment will be described.
According to the outdoor heat exchanger 3 of the present embodiment, the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b may be switched to series connection or parallel connection by the switching valve 4. Thereby, it is possible to adjust the number of refrigerant flow paths (path number) in the cooling operation mode and the heating operation mode, which makes it possible to improve the performance of the outdoor heat exchanger 3.
According to the outdoor heat exchanger 3 of the present embodiment, the number of the plurality of first refrigerant flow paths RF1 in the first outdoor heat exchanger 3a is greater than the number of the at least one second refrigerant flow paths RF2 in the second outdoor heat exchanger 3b. Therefore, if the second heat exchanger 3b is operated at a location where there is more liquid phase present in the refrigerant, it is possible to reduce the number of the refrigerant flow paths at the location where there is more liquid phase present in the refrigerant so as to increase the flow rate of the refrigerant. Therefore, it is possible to improve the heat transfer performance at a location where there is more liquid phase present in the refrigerant, which makes it possible to improve the performance of the heat exchanger 3. In addition, the switching valve 4 is configured to close the first valve flow path VF1 and the third valve flow path VF3 but open the second valve flow path VF2 or to open the first valve flow path VF1 and the third valve flow path VF3 but close the second valve flow path VF2. Therefore, it is possible to switch the first heat exchanger 3a and the second heat exchanger 3b to series connection or parallel connection with one switching valve 4, which makes it possible to downsize the heat exchanger 3. Furthermore, according to the prior art, three valves are used to switch the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b, and the three valves have a total of six inlet/outlet ports. According to the outdoor heat exchanger 3 of the present embodiment, the switching valve has only four inlet/outlet ports, which may contribute to the downsize of the outdoor heat exchanger 3.
According to the outdoor heat exchanger 3 of the present embodiment, it is possible for the switching valve 4 to open or close each of the first valve flow path VF 1, the second valve flow path VF2 and the third valve flow path VF3 by driving the shaft 11 to which the first valve 13a, the second valve 13b and the third valve 13c are attached in the axial direction. Therefore, it is possible to control each of the first valve flow path VF1, the second valve flow path VF2 and the third valve flow path VF3 at the same time, resulting in excellent operability of the first valve, the second valve and the third valve. In addition, since only one drive unit 14 is required to drive the shaft 11 to which the first valve 13a, the second valve 13b and the third valve 13c are attached, which makes it possible to reduce the cost.
According to the outdoor heat exchanger 3 of the present embodiment, the second valve flow path VF2 is sandwiched between the first valve flow path VF1 and the third valve flow path VF3. Therefore, by driving the shaft 11 to which the first valve 13a, the second valve 13b and the third valve 13c are attached in the axial direction, it is possible to close the first valve flow path VF1 and the third valve flow path VF3 but open the second valve flow path VF2 or to open the first valve flow path VF1 and the third valve flow path VF3 but close the second valve flow path VF2.
According to the outdoor heat exchanger 3 of the present embodiment, the refrigerant flowing through the first outdoor heat exchanger 3a, the second outdoor heat exchanger 3b and the switching valve 4 is a single-component refrigerant or an azeotropic refrigerant. Thus, a single-component refrigerant and an azeotropic refrigerant may be used as the refrigerant.
According to the outdoor heat exchanger 3 of the present embodiment, the refrigerant flowing through the first outdoor heat exchanger 3a, the second outdoor heat exchanger 3b and the switching valve 4 may be a zeotropic refrigerant. Therefore, a zeotropic refrigerant may be used as the refrigerant.
The refrigeration cycle apparatus of the present embodiment includes the compressor 1, the outdoor heat exchanger 3 described above, the expansion valve 5, and the indoor heat exchanger 6. Further, the heat exchanger of the present embodiment may be applied to both the outdoor heat exchanger 3 and the indoor heat exchanger 6. In other words, the heat exchanger of the present embodiment may be at least one of a condenser and an evaporator. Therefore, it is possible to provide the refrigeration cycle apparatus including at least one of the outdoor heat exchanger 3 and the indoor heat exchanger 6 with improved performance and a smaller size.

Second Embodiment

Hereinafter, unless otherwise specified, the same reference numerals will be given to the same components as those in the first embodiment described above, and the description thereof will not be repeated. The same applies to the third embodiment and the fourth embodiment to be described hereinafter.
With reference to Figs. 6 and 7, the air conditioner according to a second embodiment of the present invention is different from that of the first embodiment in the configuration of the switching valve 4. In the second embodiment, a valve 15 attached to the shaft 11 has a U-shaped flow path 15a provided inside the valve 15. The flow path 15a is configured to fluidly communicate the first inlet/outlet port P1 with the second inlet/outlet port P2, or the second inlet/outlet port P2 with the third inlet/outlet port P3, or the third inlet/outlet port P3 with the fourth inlet/outlet port P4. When the shaft 11 is driven to move in the axial direction by the drive unit 14, the valve 15 allows the first inlet/outlet port P1 and the second inlet/outlet port P2 to fluidly communicate with each other, or allows the second inlet/outlet port P2 and the third inlet/outlet port P3 to fluidly communicate with each other, or allows the third inlet/outlet port P3 and the fourth inlet/outlet port P4 to fluidly communicate with each other.
With reference to Fig. 6, in the cooling operation mode, the valve 15 is arranged at a middle position in the switching valve 4. Thus, the second valve flow path VF2 is made open by the flow path 15a of the valve 15. In other words, the valve 15 is arranged so that the refrigerant flows through the flow path 15a of the valve 15 into the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b in series. Specifically, the refrigerant flowing out from the second connection port C2 of the first outdoor heat exchanger 3a flows into the switching valve 4 through the third inlet/outlet port P3, passes through the flow path 15a of the valve 15 and flows out from the second inlet/outlet port P2, and then it flows into the second outdoor heat exchanger 3b through the third connection port C3.
With reference to Fig. 7, in the heating operation mode, the valve 15 is disposed at an upper position of the switching valve 4. Thus, the first valve flow path VF1 is made open by the flow path 15a of the valve 15. In other words, the valve 15 is arranged so that the refrigerant flows through the flow path 15a of the valve 15 into the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b in parallel. Specifically, the refrigerant flowing out from the third connection port C3 of the second outdoor heat exchanger 3b flows into the switching valve 4 through the second inlet/outlet port P2, passes through the flow path 15a of the valve 15 and flows out from the first inlet/outlet port P1, and then it flows into the four-way valve 2 illustrated in Fig. 2. Meanwhile, the refrigerant flowing into the switching valve 4 through the fourth inlet/outlet port P4, passes through the third valve flow path VF3 and flows out from the third inlet/outlet port P3, and then it flows into the first outdoor heat exchanger 3a through the second connection port C2, Thereafter, the refrigerant flowing into the first outdoor heat exchanger 3a flows out from the first connection port C1 into the four-way valve 2 illustrated in Fig. 2.
It is acceptable that in the heating operation mode, the valve 15 may be disposed at a lower position in the switching valve 4, whereby the third valve flow path VF3 is made open by the flow path 15a of the valve 15.
The valve 15 may be moved in the axial direction of the shaft 11 by a solenoid valve but it is not limited thereto, and it may be moved in the axial direction of the shaft 11 by, for example, the pressure of refrigerant.

Third Embodiment

With reference to Fig. 8, in the air conditioner according to a third embodiment of the present invention, the heat exchanger of the present invention is mounted in each of the outdoor heat exchanger 3 and the indoor heat exchanger 6. In other words, each of the condenser and the evaporator is implemented by the heat exchanger of the present invention. Therefore, in the air conditioner according to the third embodiment, the number of the refrigerant flow paths (path number) is variable in both the outdoor heat exchanger 3 and the indoor heat exchanger 6.
When the outdoor heat exchanger 3 is functioning as a condenser, the indoor heat exchanger 6 will function as an evaporator, whereby the operation of the switching valve 4 is reversed. When the switching valve 4 (4a) of the outdoor heat exchanger 3 is switched to connect the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b in series, the switching valve 4 (4b) of the indoor heat exchanger 6 will be switched to connect the first indoor heat exchanger 6a and the second indoor heat exchanger 6b in parallel.
On the other hand, when the indoor heat exchanger 6 is functioning as a condenser, the outdoor heat exchanger 3 will function as an evaporator, whereby the operation of the switching valve 4 is reversed. When the switching valve 4 (4b) of the indoor heat exchanger 6 is switched to connect the first indoor heat exchanger 6a and the second indoor heat exchanger 6b in series, the switching valve 4 (4a) of the outdoor heat exchanger 3 will be switched to connect the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b in parallel.

Fourth Embodiment

With reference to Figs. 9 and 10, the air conditioner according to a fourth embodiment of the present invention is different from that of the first embodiment in the configuration of the switching valve 4. In the fourth embodiment, the switching valve 4 is a circular rotary valve.
The switching valve 4 includes a main body 10, a shaft 11, a flat plate-shaped valve seat 12, and a valve 13. The main body 10 has a cylinder shape. The shaft 11 is connected to a motor (not shown). The valve seat 12 has a flat plate shape. The valve 13 has a column shape. The flat plate-shaped valve seat 12 and the column-shaped valve 13 are arranged in the cylinder-shaped main body 10. The valve seat 12 is provided with a first inlet/outlet port P1, a second inlet/outlet port P2, a third inlet/outlet port P3, and a fourth inlet/outlet port P4.
The valve 13 is slidable on one face of the valve seat 12. The valve 13 is provided with a first flow path 131 and a second flow path 132. The shaft 11 is connected to the center of the valve 13. As the shaft 11 is rotated by the driving force from a motor (not shown), the cylindrical valve 13 rotates in the circumferential direction as indicated by an arc arrow in the figure.
The valve 13 is configured to rotate in the circumferential direction by the rotation of the shaft 11 so as to fluidly communicate the first inlet/outlet port P1 with the second inlet/outlet port P2 via the first flow path 131 or fluidly communicate the second inlet/outlet port P2 with the third inlet/outlet port P3 via the second flow path 132.
With reference to Fig. 9, the outdoor heat exchanger 3 will be described when it is used as a condenser (in the cooling operation mode). The flow path of the switching valve 4 is set so that the refrigerant flows through the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b in series. In other words, the valve 13 is arranged so that the refrigerant passes through the second flow path 132, and flows through the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b in series. Specifically, as indicated by the straight arrows in the figure, the refrigerant flowing out from the second connection port C2 of the first outdoor heat exchanger 3a flows into the second flow path 132 through the third inlet/outlet port P3, then it flows through the second flow path 132 and out from the second inlet/outlet port P2, and finally the refrigerant flows into the second outdoor heat exchanger 3b through the third connection port C3.
With reference to Fig. 10, the outdoor heat exchanger 3 will be described when it is used as an evaporator (in the heating operation mode). When the valve 13 is rotated from the state illustrated in Fig. 9, the refrigerant circuit illustrated in Fig. 10 is obtained. The flow path of the switching valve 4 is set so that the refrigerant flows through the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b in parallel. In other words, the valve 13 is arranged so that the refrigerant flows in parallel into the first outdoor heat exchanger 3a and the second outdoor heat exchanger 3b through the first flow path 131 and the second flow path 132. Specifically, as indicated by the arrows in the figure, the refrigerant flowing out from the third connection port C3 of the second outdoor heat exchanger 3b flows into the first flow path 131 through the second inlet/outlet port P2, then it flows through the first flow path 131 and out from the first inlet/outlet port P1, and finally it flows into the four-way valve 2 illustrated in Fig. 2. Meanwhile, the refrigerant flowing into the second flow path 132 through the fourth inlet/outlet port P4 flows out from the third inlet/outlet port P3 through the second flow path 132, and then it flows into the first outdoor heat exchanger 3a through the second connection port C2.
According to the heat exchanger of the present embodiment, the performance of the heat exchanger may be improved as in the first embodiment. Therefore, it is possible to provide a heat exchanger with improved performance and a smaller size as well as a refrigerating cycle apparatus including the heat exchanger.
The embodiments described above may be combined appropriately.
The embodiments disclosed herein are merely by way of example and not limited thereto. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the meaning and scope equivalent to the terms of the claims.

REFERENCE SIGNS LIST

1: compressor; 2: four-way valve; 3: outdoor heat exchanger; 3a: first outdoor heat exchanger; 3b: second outdoor heat exchanger; 4: switching valve; 5: expansion valve; 5a: first expansion valve; 5b: second Expansion valve; 6: indoor heat exchanger; 6a: first indoor heat exchanger; 6b: second indoor heat exchanger; 10: main body; 11: shaft; 12: valve seat; 12a: first valve seat; 12b: second valve seat; 12c: third valve seat; 13: valve; 13a: first valve; 13b: second valve; 13c: third valve; 14: drive unit; 14a: movable member; 14b: coil; 15: valve; 15a: flow path; C1: first connection port; C2: second connection port; C3: third connection port; C4: fourth connection port; P1: first inlet/outlet port; P2: second inlet/outlet port; P3: third inlet/outlet port; P4: fourth inlet/outlet port; RF1: first refrigerant flow path; RF2: second refrigerant flow path; VF1: first valve flow path; VF2: second valve flow path; VF3: third valve flow path

Claims

A heat exchanger (3) comprising:
a first heat exchanger unit (3a) including
a plurality of first refrigerant flow paths (RF1),

a first connection port (C1) in fluid communication with the plurality of first refrigerant flow paths (RF1), and

a second connection port (C2) provided on the side opposite to the first connection port (C1) and configured to be in fluid communication with the plurality of first refrigerant flow paths (RF1);

a second heat exchanger unit (3b) including
at least one second refrigerant flow path (RF2),

a third connection port (C3) in fluid communication with the second refrigerant flow path (RF2), and

a fourth connection port (C4) provided on the side opposite to the third connection port (C3) and configured to be in fluid communication with the second refrigerant flow path (RF2); and

a switching valve (4) including
a first inlet/outlet port (P1) connected to the first connection port (C1),

a second inlet/outlet port (P2) connected to the third connection port (C3),

a third inlet/outlet port (P3) connected to the second connection port (C2),

a fourth inlet/outlet port (P4) connected to the fourth connection port (C4),

a first valve flow path (VF1) configured to fluidly communicate the first inlet/outlet port (P1) with the second inlet/outlet port (P2),

a second valve flow path (VF2) configured to fluidly communicate the second inlet/outlet port (P2) with the third inlet/outlet port (C3), and

a third valve flow path (VF3) configured to fluidly communicate the third inlet/outlet port (P3) with the fourth inlet/outlet port (P4),

the number of the plurality of first refrigerant flow paths (RF1) in the first heat exchanger unit (3a) being configured to be greater than the number of the at least one second refrigerant flow path (RF2) in the second heat exchanger unit (3b), and

the switching valve (4) being configured to close the first valve flow path (VF1) and the third valve flow path (VF3) but open the second valve flow path (VF2) or to open the first valve flow path (VF1) and the third valve flow path (VF3) but close the second valve flow path (VF2).
The heat exchanger according to claim 1, wherein
the switching valve (4) includes
a first valve seat (12a) disposed in the first valve flow path (VF1),

a first valve (13a) configured to close the first valve flow path (VF1) by coming into contact with the first valve seat (12a) and open the first valve flow path (VF1) by leaving away from the first valve seat (13a),

a second valve seat (12b) disposed in the second valve flow path (VF2),

a second valve (13b) configured to close the second valve flow path (VF2) by coming into contact with the second valve seat (12b) and open the second valve flow path (VF2) by leaving away from the second valve seat (12b),

a third valve seat (12c) disposed in the third valve flow path (VF3),

a third valve (13c) configured to close third valve flow path (VF3) by coming into contact with the third valve seat (12c) and open the third valve flow (VF3) path by leaving away from the third valve seat (12c),

a shaft (11) to which the first valve (13a), the second valve (13b) and the third valve (13c) are attached, and

a drive unit (14) configured to drive the shaft (11) in the axial direction.
The heat exchanger according to claim 1 or 2, wherein
the second valve flow path (VF2) is sandwiched between the first valve flow path (VF1) and the third valve flow path (VF3).
The heat exchanger according to any one of claims 1 to 3, wherein
the refrigerant flowing through the first heat exchanger unit (3a), the second heat exchanger unit (3b) and the switching valve (4) is a single-component refrigerant or an azeotropic refrigerant.
The heat exchanger according to any one of claims 1 to 3, wherein
the refrigerant flowing through the first heat exchanger unit (3a), the second heat exchanger unit (3b) and the switching valve (4) is a zeotropic refrigerant.
A refrigeration cycle apparatus comprising a compressor (1) configured to compress sucked refrigerant and discharge the compressed refrigerant, a condenser configured to condense the refrigerant compressed by the compressor (1), a throttle device configured to decompress the refrigerant condensed by the condenser, and an evaporator configured to evaporate the refrigerant decompressed by the throttle device,
the condenser or the evaporator is the heat exchanger according to any one of claims 1 to 5.