Heat exchangers and refrigeration systems

Abstract

The present invention provides a heat exchanger that enables heat exchange between multiple fluids while suppressing the need for large-scale construction, and a refrigeration system using the same. [Solution] The heat exchanger is composed of multiple stacked layers. The heat exchanger comprises a first layer and a second layer stacked on the first layer. The first layer is divided into a first part through which a first fluid flows and a second part through which a second fluid flows. The second layer has a third part and a fourth part. The third part overlaps with the second part in a plan view and is the part through which the third fluid flows. The fourth part overlaps with the first part in a plan view and is the part through which the third fluid flows. The third fluid flows through the third part and then through the fourth part.

Description

Technical Field

[0001] It relates to a heat exchanger and a refrigeration device.

Background Art

[0002] Patent Document 1 (Japanese Patent Application Laid-Open No. 2008-298407) discloses a multi-heat pump type steam / warm water generation device (refrigeration device) having a multi-refrigerant circuit that stepwise heats a refrigerant or a heat medium by a plurality of refrigeration cycles. The refrigeration device disclosed in Patent Document 1 has a plurality of heat exchangers and a cascade condenser for stepwise heating a fluid such as a refrigerant or a heat medium.

Summary of the Invention

Problems to be Solved by the Invention

[0003] A refrigeration device having a multi-refrigerant circuit requires a plurality of heat exchangers for heat exchange between a plurality of different fluids, making it difficult to miniaturize. Therefore, there has been a need for a small heat exchanger capable of performing heat exchange between a plurality of different fluids.

[0004] An object of the present disclosure is to provide a heat exchanger capable of suppressing an increase in size while enabling heat exchange between a plurality of fluids, and a refrigeration device using the same.

Means for Solving the Problems

[0005] The heat exchanger according to the first aspect is composed of a plurality of stacked layers. The heat exchanger includes a first layer and a second layer stacked on the first layer. The first layer is separated into a first portion through which a first fluid flows and a second portion through which a second fluid flows. The second layer has a third portion and a fourth portion. The third portion overlaps the second portion in a plan view and is a portion through which a third fluid flows. The fourth portion overlaps the first portion in a plan view and is a portion through which the third fluid flows. The third fluid flows through the fourth portion after flowing through the third portion.

[0006] In the first layer of the heat exchanger, the first and second fluids flow through the first and second sections, which are separated from each other. In the second layer of the heat exchanger, the third fluid flows through the third section, which overlaps with the second section, and the fourth section, which overlaps with the first section. As a result, the heat exchanger can exchange heat between the first fluid and the third fluid, and between the second fluid and the third fluid. Furthermore, since the first and second sections, the third and fourth sections are each formed in a single layer, and these layers are stacked, the size of the heat exchanger is kept from increasing.

[0007] Therefore, this heat exchanger can enable heat exchange between multiple fluids while keeping its size down.

[0008] The heat exchanger in the second view is the heat exchanger in the first view, wherein the temperature of the third fluid at the outlet of the third section is higher than the temperature of the third fluid at the inlet of the third section. The temperature of the third fluid at the outlet of the fourth section is higher than the temperature of the third fluid at the inlet of the fourth section.

[0009] In the heat exchanger of the second perspective, the third fluid is heated by exchanging heat with the first and second fluids.

[0010] A heat exchanger in the third view is a heat exchanger in the first or second view, wherein the first part has a first flow path through which a first fluid flows. The second part has a second flow path through which a second fluid flows. The third part has a third flow path through which a third fluid flows. The fourth part has a fourth flow path through which a third fluid flows. The third fluid flows through the third flow path from the first end, which is one end in a predetermined first direction, to the second end, which is the other end in the first direction. In a plan view of the first layer, the second fluid flows through the second flow path in a direction opposite to the direction through which the third fluid flows.

[0011] The heat exchanger from the third perspective can exchange heat between the second and third fluids more efficiently.

[0012] The heat exchanger in the fourth view is either the heat exchanger in the first view or the heat exchanger in the third view, in which the third fluid flows through the fourth channel from the first end to the second end. The first fluid flows through the first channel in a direction opposite to the direction in which the third fluid flows, in a plan view of the first layer.

[0013] The heat exchanger in the fourth aspect can exchange heat between the first and third fluids more efficiently.

[0014] The heat exchanger of the fifth perspective is any of the heat exchangers of the first, second, or fourth perspectives, wherein the third and fourth parts are aligned in a second direction perpendicular to the first direction in a plan view of the second layer. The second layer further has a connecting channel that connects the third channel and the fourth channel. The third fluid flows in the order of the third channel, the connecting channel, and the fourth channel, and flows through the connecting channel from the second end to the first end.

[0015] The heat exchanger of the sixth aspect is any of the heat exchangers of the first aspect to the fifth aspect, wherein the third flow path has multiple flow paths.

[0016] The heat exchanger of the seventh aspect is any of the heat exchangers of the first to fifth aspects, wherein the third fluid flows through the third flow path along the second direction, from the third end, which is one end in the second direction, to the fourth end, which is the other end in the second direction. The third fluid then flows along the first direction from the first end to the second end, then along the second direction from the fourth end to the third end, and then along the first direction from the first end to the second end.

[0017] The heat exchanger in the eighth perspective is any of the heat exchangers in the first to fifth perspectives, wherein the third part is positioned vertically below the fourth part. The third fluid flows along the vertical up-and-down direction through the third and fourth channels.

[0018] The heat exchanger of the ninth aspect is any of the heat exchangers of the first aspect to the seventh aspect, where the first and second fluids are refrigerants. The third fluid is water. The first end is located vertically below the second end.

[0019] The heat exchanger of the 10th aspect is any one of the heat exchangers of the 1st to 9th aspects, and the first layer further has a fifth portion through which a first fluid flowing through the first portion flows. The second layer is laminated on the fifth portion and further has a sixth portion through which a second fluid flows.

[0020] This heat exchanger can further cause heat exchange between the first fluid flowing through the fifth portion and the second fluid flowing through the sixth portion P6.

[0021] The heat exchanger of the 11th aspect is any one of the heat exchangers of the 1st or 2nd aspect, and a third fluid flows from the second end side to the first end side through the fourth flow path. The first fluid flows in a direction facing the third fluid through the first flow path in a plan view of the first layer.

[0022] The heat exchanger of the 12th aspect is the heat exchanger of the 1st aspect, and the temperature of the third fluid at the outlet of the third portion is higher than the temperature of the third fluid at the inlet of the third portion. The temperature of the third fluid at the outlet of the fourth portion is lower than the temperature of the third fluid at the inlet of the fourth portion.

[0023] In the heat exchanger of the 12th aspect, the third fluid flowing through the third portion is heated by heat exchange with the first fluid, and the third fluid flowing through the fourth portion is cooled by heat exchange with the second fluid.

[0024] The refrigeration device of the 13th aspect includes the heat exchanger of the 1st to 12th aspects.

[0025] By suppressing the increase in size of the above-described heat exchanger, the increase in size of this refrigeration device is also suppressed.

Brief Description of Drawings

[0026] [Figure 1] It is a schematic diagram of the refrigeration device 1. [Figure 2] It is a perspective view of the heat exchanger 100. [Figure 3] It is a plan view of the first layer L1. [Figure 4] It is a plan view of the second layer L2. [Figure 5] It is a plan view of the second layer L2 of the heat exchanger 100 according to Modified Example 1. [Figure 6] It is a plan view of the second layer L2 of the heat exchanger 100 according to Modified Example 2. [Figure 7] It is a plan view of the second layer L2 of the heat exchanger 100 according to Modified Example 2. [Figure 8] It is a schematic diagram of the refrigeration device 2 according to the second embodiment.

Mode for Carrying Out the Invention

[0027] <First Embodiment> (1) Overall configuration of the refrigeration device , First, a refrigeration device 1 including a heat exchanger 100 according to the first embodiment of the present disclosure will be described. FIG. 1 is a schematic diagram of the refrigeration device 1. The refrigeration device 1 is a refrigeration cycle device that performs heating and cooling operations on an air-conditioning target space (not shown) such as the interior of a building by executing a vapor compression cycle.

[0028] The refrigeration device 1 according to the present embodiment includes an outdoor unit 10, an indoor unit 20, a first refrigerant circuit 30, a second refrigerant circuit 40, a heat medium circuit 5 , and a heat exchanger 100.

[0029] A part of the first refrigerant circuit 30 is housed in the outdoor unit 10, and the remaining part is housed in the indoor unit 20. A part of the second refrigerant circuit 40, a part of the heat medium circuit 50, and the heat exchanger 100 are housed in the indoor unit 20.

[0030] The first refrigerant circuit 30 is filled with a first refrigerant. The second refrigerant circuit 40 is filled with a second refrigerant. The heat medium circuit 50 is filled with a heat medium. The first refrigerant is carbon dioxide. The second refrigerant is R290 (propane). The heat medium is water.

[0031] The first refrigerant is an example of the first fluid. The second refrigerant is an example of the second fluid. The heat medium is an example of the third fluid.

[0032] (1-1) Heat exchanger 100 The heat exchanger 100 facilitates heat exchange between the first refrigerant, the second refrigerant, and the heat transfer medium. The heat exchanger 100 has a first flow path 110, a second flow path 120, a third flow path 130, a fourth flow path 140, a fifth flow path 150, and a sixth flow path 160. In the following description, when it is not necessary to distinguish between the first flow path 110, the second flow path 120, the third flow path 130, the fourth flow path 140, the fifth flow path 150, and the sixth flow path 160, they may be collectively referred to as flow path c.

[0033] The first channel 110 and the fifth channel 150 are channels through which the first refrigerant flows. The second channel 120 and the sixth channel 160 are through which the second refrigerant flows. The third channel 130 and the fourth channel 140 are through which the heat transfer medium flows.

[0034] The first refrigerant flowing through the first channel 110 and the heat transfer medium flowing through the third channel 130 exchange heat with each other. The second refrigerant flowing through the second channel 120 and the heat transfer medium flowing through the fourth channel 140 exchange heat with each other. The first refrigerant flowing through the fifth channel 150 and the second refrigerant flowing through the sixth channel 160 exchange heat with each other. The detailed structure of the heat exchanger 100 will be described later.

[0035] (1-2) First refrigerant circuit 30 The first refrigerant circuit 30 includes a first compressor 31, a heat source heat exchanger 32, a four-way switching valve 33, a receiver tank 34, a bridge circuit 35, expansion valves 36a and 36b, connecting pipes 37a and 37b, cocks 38a and 38b, and the first flow path 110 and fifth flow path 150 of the heat exchanger 100. The first compressor 31, heat source heat exchanger 32, four-way switching valve 33, receiver tank 34, bridge circuit 35, and expansion valves 36a and 36b are housed in the outdoor unit 10. The cocks 38a and 38b are housed in the indoor unit 20.

[0036] (1-2-1) First compressor 31 The first compressor 31 draws in the low-pressure refrigerant from the first refrigerant circuit 30 through the suction port 31a, compresses it, and then discharges it as high-pressure refrigerant through the discharge port 31b.

[0037] (1-2-2) Heat source heat exchanger 32 The heat source heat exchanger 32 causes heat exchange between the refrigerant circulating in the first refrigerant circuit 30 and a heat source (for example, outdoor air). The heat source heat exchanger 32 has a gas-side end 32a and a liquid-side end 32b.

[0038] (1-2-3) Four-way switching valve 33 The four-way switching valve 33 has a first port 33a, a second port 33b, a third port 33c, and a fourth port 33d. Based on instructions from the control unit (not shown), the four-way switching valve 33 switches between a first state and a second state in which the communication status of the first port 33a, second port 33b, third port 33c, and fourth port 33d is different. In the first state, the first port 33a and the second port 33b are in communication, and the third port 33c and the fourth port 33d are in communication. In the second state, the first port 33a and the fourth port 33d are in communication, and the second port 33b and the third port 33c are in communication.

[0039] The first port 33a is connected to the discharge section 31b of the first compressor 31. The second port 33b is connected to the end of the connecting pipe 37b on the outdoor unit 10 side. The third port 33c is connected to the suction section 31a of the first compressor 31. The fourth port 33d is connected to the gas side end 32a of the heat source heat exchanger 32.

[0040] (1-2-4) Receiver Tank 34 The receiver tank 34 stores excess refrigerant, thereby circulating an appropriate amount of refrigerant within the first refrigerant circuit 30. The receiver tank 34 has an inlet 34a and an outlet 34b. Refrigerant flows into the receiver tank 34 from the inlet 34a. The refrigerant that has flowed into the receiver tank 34 flows out from the outlet 34b.

[0041] (1-2-5) Bridge circuit 35 The bridge circuit 35 has a first connection point 35ab, a second connection point 35bc, a third connection point 35cd, and a fourth connection point 35da.

[0042] A second check valve 35b is provided between the first connection point 35ab and the second connection point 35bc, which restricts the flow of refrigerant from the first connection point 35ab to the second connection point 35bc and allows the flow of refrigerant in the reverse direction. A third check valve 35c is provided between the second connection point 35bc and the third connection point 35cd, which allows the flow of refrigerant from the second connection point 35bc to the third connection point 35cd and restricts the flow of refrigerant in the reverse direction. A fourth check valve 35d is provided between the third connection point 35cd and the fourth connection point 35da, which allows the flow of refrigerant from the third connection point 35cd to the fourth connection point 35da and restricts the flow of refrigerant in the reverse direction. A first check valve 35a is provided between the fourth connection point 35da and the first connection point 35ab, which restricts the flow of refrigerant from the fourth connection point 35da to the first connection point 35ab and allows the flow of refrigerant in the reverse direction.

[0043] The first connection point 35ab is connected to the end of the connecting pipe 37a on the outdoor unit 10 side. The second connection point 35bc is connected to the outlet 34b of the receiver tank 34. The third connection point 35cd is connected to the liquid side end 32b of the heat source heat exchanger 32. The fourth connection point 35da is connected to the inlet 34a of the receiver tank 34.

[0044] (1-2-6) Expansion valves 36a, 36b The expansion valves 36a and 36b adjust the flow rate of the refrigerant passing through them and reduce the pressure by changing their opening degree based on instructions from the control unit (not shown).

[0045] The expansion valve 36a is provided in the refrigerant piping connecting the outlet 34b of the receiver tank 34 and the second connection point 35bc of the bridge circuit 35. The expansion valve 36b is provided in the refrigerant piping connecting the inlet 34a of the receiver tank 34 and the fourth connection point 35da of the bridge circuit 35.

[0046] (1-2-7) Connecting pipes 37a, 37b The connecting pipes 37a and 37b are pipes that connect the first refrigerant circuit 30 on the outdoor unit 10 side to the first refrigerant circuit 30 on the indoor unit 20 side.

[0047] (1-2-8) Cock 38a, 38b Cocks 38a and 38b are provided in the refrigerant piping and control the flow of refrigerant within the refrigerant piping. More specifically, cocks 38a and 38b change between an open state and a closed state based on instructions from a control unit (not shown). When cocks 38a and 38b are open, they allow the flow of refrigerant within the refrigerant piping, and when closed, they restrict the flow of refrigerant within the refrigerant piping.

[0048] The cock 38a is provided in the refrigerant piping that connects the end of the connecting pipe 37b on the indoor unit 20 side to the first flow path 110 of the heat exchanger 100.

[0049] The cock 38b is provided in the bypass piping 38c that bypasses both ends of the first flow path 110 of the heat exchanger 100.

[0050] (1-2-9) First flow path 110 and fifth flow path 150 of heat exchanger 100 The first flow path 110 of the heat exchanger 100 has one end 110a connected to the other end 150b of the fifth flow path 150, and the other end 110b connected to the end of the connecting pipe 37b on the indoor unit 20 side.

[0051] The fifth flow path 150 of the heat exchanger 100 has one end 150a connected to the end of the connecting pipe 37a on the indoor unit 20 side, and the other end 150b connected to one end 110a of the first flow path 110.

[0052] (1-3) Second refrigerant circuit 40 The second refrigerant circuit 40 includes a second compressor 41, an expansion mechanism 42, and a second flow path 120 and a sixth flow path 160 of the heat exchanger 100.

[0053] (1-3-1) Second compressor 41 The second compressor 41 draws in the low-pressure refrigerant from the second refrigerant circuit 40 through the suction port 41a, compresses it, and then discharges it as high-pressure refrigerant through the discharge port 41b.

[0054] (1-3-2) Expansion mechanism 42 The expansion mechanism 42 regulates and reduces the flow rate of the refrigerant passing through it. The expansion mechanism 42 is, but is not limited to, a capillary tube.

[0055] (1-3-3) The second flow path 120 and the sixth flow path 160 of the heat exchanger 100 The second flow path 120 of the heat exchanger 100 has one end 120a connected to the discharge section 41b of the second compressor 41, and the other end 120b connected to one end 42a of the expansion mechanism 42.

[0056] The sixth flow path 160 of the heat exchanger 100 has one end 160a connected to the other end 42b of the expansion mechanism 42, and the other end 160b connected to the suction section 41a of the second compressor 41.

[0057] (1-4)Heating medium circuit 50 The heat transfer medium circuit 50 includes a circulation pump 51, utilization heat exchangers 52a and 52b, a tank 53, and the third flow path 130 and fourth flow path 140 of the heat exchanger 100. The third flow path 130 and fourth flow path 140 of the heat exchanger 100 are housed in the indoor unit 20.

[0058] (1-4-1) Circulation pump 51 The circulation pump 51 circulates the heat transfer medium within the heat transfer medium circuit 50. The circulation pump 51 draws in the heat transfer medium filled in the heat transfer medium circuit 50 from the suction port 51a and discharges it from the discharge port 51b.

[0059] (1-4-2) Utilized heat exchanger 52a, 52b The utilization heat exchanger 52a facilitates heat exchange between the heat transfer medium circulating in the heat transfer medium circuit 50 and the water stored in the tank 53. The utilization heat exchanger 52a is located inside the tank 53. One end 52aa of the utilization heat exchanger 52a is connected to the other end 140b (described later) of the fourth flow path 140, and the other end 52ab is connected to the suction part 51a of the circulation pump 51.

[0060] The heat exchanger 52b facilitates heat exchange between the heat transfer medium circulating in the heat transfer medium circuit 50 and the air in the space to be air-conditioned (not shown). One end 52ba of the heat exchanger 52b is connected to the other end 140b (described later) of the fourth flow path 140, and the other end 52bb is connected to the suction part 51a of the circulation pump 51. Multiple heat exchangers 52b may be provided.

[0061] (1-4-3) Tank 53 Tank 53 stores water that exchanges heat with the heat transfer medium circulating in the heat transfer medium circuit 50. Tank 53 takes in water supplied from outside the refrigeration device 1 through an intake section (not shown) and discharges the water that has exchanged heat with the heat transfer medium through a drainage section (not shown).

[0062] (1-4-4) Third channel 130 and fourth channel 140 of heat exchanger 100 The third flow path 130 of the heat exchanger 100 has one end 130a connected to the discharge section 51b of the circulation pump 51.

[0063] The fourth flow path 140 of the heat exchanger 100 has one end 140a connected to the other end 130b of the third flow path 130.

[0064] (1-5) Operation of refrigeration unit 1 The refrigeration unit 1 performs heating and cooling operations. The heating operation further includes a first heating operation and a second heating operation.

[0065] (1-5-1) Heating operation The heating operation involves heating the water stored in the tank 53 using the utilization heat exchanger 52a, and heating the air in the air-conditioned space using the utilization heat exchanger 52b. The second heating operation provides a higher heating capacity than the first heating operation.

[0066] (1-5-1-1) First heating operation In the first heating operation, the first compressor 31, the second compressor 52, and the circulation pump 51 are all driven, the four-way switching valve 33 is controlled to the first state, and the opening degree of the expansion valves 36a and 36b is controlled. In the first heating operation, cock 38a is controlled to the closed state, and cock 38b is controlled to the open state.

[0067] (1st refrigerant circuit 30) The first compressor 31 draws in the first refrigerant in the low-pressure gas phase from the first refrigerant circuit 30 through the suction port 31a and discharges it as the first refrigerant in the high-pressure gas phase from the discharge port 31b. The first refrigerant, which is in the high-pressure gas phase, flows into the connecting pipe 37b through the four-way switching valve 33 in the order of the first port 33a and the second port 33b. The first refrigerant that has flowed out of the connecting pipe 37b flows into the fifth flow path 150 of the heat exchanger 100 from the other end 150b through the bypass pipe 38c and the open cock 38b. Since the cock 38a is in the closed position, the first refrigerant that has flowed out of the connecting pipe 37b does not pass through the first flow path 110. In the fifth flow path 150, the first refrigerant in the high-pressure gas phase condenses to become the first refrigerant in the high-pressure liquid phase. At this time, the first refrigerant releases heat to the second refrigerant that passes through the sixth flow path 160.

[0068] The high-pressure liquid-phase first refrigerant flowing out from the fifth flow path 150 flows into the bridge circuit 35 from the first connection point 35ab through the connecting pipe 37a, and flows out from the fourth connection point 35da through the first check valve 35a. The first refrigerant flowing out of the bridge circuit 35 passes through the expansion valve 36b, the receiver tank 34, and the expansion valve 36a. The expansion valves 36b and 36a, set to an appropriate opening degree, reduce the pressure of the high-pressure liquid-phase first refrigerant to a low-pressure gas-liquid two-phase first refrigerant. The low-pressure gas-liquid two-phase first refrigerant flows back into the bridge circuit 35 from the second connection point 35bc, and flows out from the third connection point 35cd through the third check valve 35c. The first refrigerant flowing out of the bridge circuit 35 evaporates in the heat source heat exchanger 32 to become a low-pressure gas-phase first refrigerant. At this time, the first refrigerant absorbs heat from the heat source. The first refrigerant in the low-pressure gas phase that flows out from the heat source heat exchanger 32 passes through the four-way switching valve 33 in the order of the fourth port 33d and the third port 33c, and is then drawn into the first compressor 31 from the suction port 31a.

[0069] (Second refrigerant circuit 40) The second compressor 41 draws in the second refrigerant in the low-pressure gas phase from the second refrigerant circuit 40 through the suction port 41a and discharges it as the second refrigerant in the high-pressure gas phase from the discharge port 41b. The second refrigerant in the high-pressure gas phase flows into the second flow path 120 of the heat exchanger 100 from one end 120a. In the second flow path 120, the second refrigerant in the high-pressure gas phase condenses to become the second refrigerant in the high-pressure liquid phase. At this time, the second refrigerant releases heat to the heat transfer medium passing through the fourth flow path 140. The second refrigerant in the high-pressure liquid phase that has flowed out of the second flow path 120 is depressurized by the expansion mechanism 42 and becomes the second refrigerant in the low-pressure gas-liquid two-phase state. The second refrigerant in the low-pressure gas-liquid two-phase state flows into the sixth flow path 160 from one end 160a and evaporates in the sixth flow path 160 to become the second refrigerant in the low-pressure gas phase state. At this time, the second refrigerant absorbs heat from the first refrigerant passing through the fifth flow path 150. The second refrigerant in the low-pressure gas phase that flows out from the sixth flow path 160 is drawn back into the second compressor 41 from the suction section 41a.

[0070] (heat medium circuit 50) The circulation pump 51 draws in the heat transfer medium circulating in the heat transfer medium circuit 50 from the suction port 51a and discharges it from the discharge port 51b. The discharged heat transfer medium flows into the third flow path 130 of the heat exchanger 100 from one end 130a. As described above, in the first heating operation, the first refrigerant does not pass through the first flow path 110, so the heat transfer medium that flows into the third flow path 130 does not substantially exchange heat with the first refrigerant. The heat transfer medium that flows out of the third flow path 130 flows into the fourth flow path 140 from one end 140a. The heat transfer medium that flows into the fourth flow path 140 absorbs heat from the second refrigerant passing through the second flow path 120. The heat transfer medium that flows out of the fourth flow path 140 flows into the utilization heat exchangers 52a and 52b. The heat transfer medium that flows into the utilization heat exchanger 52a releases heat into the water stored in the tank 53. The heat transfer medium that flows into the heat exchanger 52b releases heat into the air in the space being air-conditioned. In other words, the heat transfer medium that flows into the heat exchanger 52a heats the water stored in the tank 53, and the heat transfer medium that flows into the heat exchanger 52b heats the air in the space being air-conditioned. The heat transfer medium that flows out of the heat exchangers 52a and 52b is drawn back into the circulation pump 51 from the suction port 31a.

[0071] (1-5-1-2) Second heating operation The explanation of the second heating operation will focus on the differences from the first heating operation, and explanations of similar points may be omitted. In the second heating operation, cock 38a is controlled to the open state, and cock 38b is controlled to the closed state.

[0072] (1st refrigerant circuit 30) The first refrigerant, which is the high-pressure gas phase discharged from the discharge port 31b of the first compressor 31, flows into the connecting pipe 37b through the four-way switching valve 33 in the order of the first port 33a and then the second port 33b. The first refrigerant that has flowed out of the connecting pipe 37b flows into the first flow path 110 of the heat exchanger 100 from the other end 110b through the cock 38a, which is in the open state. Since the cock 38b is in the closed state, the first refrigerant that has flowed out of the connecting pipe 37b does not pass through the bypass pipe 38c. The first refrigerant, which is the high-pressure gas phase, condenses in the first flow path 110 to become the first refrigerant, which is the high-pressure liquid phase. At this time, the first refrigerant releases heat to the heat transfer medium passing through the third flow path 130. The first refrigerant, which is the high-pressure liquid phase, that has flowed out of the first flow path 110 flows into the fifth flow path 150 of the heat exchanger 100 from the other end 150b. The first refrigerant flowing into the fifth channel 150 releases heat to the second refrigerant passing through the sixth channel 160 within the fifth channel 150. The first refrigerant flowing out from the fifth channel 150 flows into the bridge circuit 35 from the first connection point 35ab via the connecting pipe 37a. The subsequent operation of each part in the first refrigerant circuit 30 is the same as in the first heating operation, so the explanation is omitted.

[0073] (Second refrigerant circuit 40) Since the operation of each part in the second refrigerant circuit 40 is the same as in the first heating operation, the explanation will be omitted.

[0074] (heat medium circuit 50) The circulation pump 51 draws in the heat transfer medium circulating in the heat transfer medium circuit 50 from the suction port 51a and discharges it from the discharge port 51b. The discharged heat transfer medium flows into the third flow path 130 of the heat exchanger 100 from one end 130a. The heat transfer medium that flows into the third flow path 130 absorbs heat from the first refrigerant passing through the first flow path 110. The operation of each part in the heat transfer medium circuit 50 thereafter is the same as in the first heating operation, so the explanation is omitted.

[0075] (1-5-2) Cooling operation Cooling operation involves using the heat exchanger 52a to cool the water stored in the tank 53, and using the heat exchanger 52b to cool the air in the space to be air-conditioned.

[0076] In cooling operation, both the first compressor 31 and the circulation pump 51 are driven, the four-way switching valve 33 is controlled to the second state, and the opening degree of the expansion valves 36a and 36b is controlled. In cooling operation, cock 38a is controlled to the open state, and cock 38b is controlled to the closed state. In cooling operation, the second compressor 41 is not driven.

[0077] (1st refrigerant circuit 30) The first compressor 31 draws in the first refrigerant in the low-pressure gas phase from the first refrigerant circuit 30 through the suction port 31a and discharges it as the first refrigerant in the high-pressure gas phase from the discharge port 31b. The first refrigerant in the high-pressure gas phase flows into the heat source heat exchanger 32 through the four-way switching valve 33 in the order of the first port 33a and then the fourth port 33d. The first refrigerant in the high-pressure gas phase condenses in the heat source heat exchanger 32 to become the first refrigerant in the high-pressure liquid phase. At this time, the first refrigerant releases heat to the heat source. The first refrigerant in the high-pressure liquid phase that has flowed out of the heat source heat exchanger 14 flows into the bridge circuit 35 from the third connection point 35cd and flows out from the fourth connection point 35da through the fourth check valve 35d. The first refrigerant that has flowed out of the bridge circuit 35 passes through the expansion valve 36b, the receiver tank 34, and the expansion valve 36a. The expansion valves 36b and 36a, set to the appropriate opening degree, reduce the pressure of the high-pressure liquid phase first refrigerant to convert it into a low-pressure gas-liquid two-phase first refrigerant. The low-pressure gas-liquid two-phase first refrigerant flows back into the bridge circuit 35 from the second connection point 35bc and flows out from the first connection point 35ab through the second check valve 35b.

[0078] The first refrigerant that flows out of the bridge circuit 35 flows through the connecting pipe 37a and into the fifth flow path 150 of the heat exchanger 100 from one end 150a. In cooling operation, the second compressor 41 is not driven, so the second refrigerant does not circulate in the second refrigerant circuit 40. Therefore, the first refrigerant does not substantially exchange heat with the second refrigerant in the fifth flow path 150. The first refrigerant that flows out of the fifth flow path 150 flows into the first flow path 110 from one end 110a. In the first flow path 110, the first refrigerant evaporates and becomes the first refrigerant in a low-pressure gas phase. At this time, the first refrigerant absorbs heat from the heat transfer medium passing through the third flow path 130. Since the cock 38b is closed, the first refrigerant that flows out of the fifth flow path 150 does not pass through the bypass pipe 38c. The first refrigerant that flows out from the first flow path 110 flows into the four-way switching valve 33 through the connecting pipe 37b, passes through the fourth port 33d and the third port 33c in that order, and is then drawn back into the first compressor 31 from the suction section 31a.

[0079] (Second refrigerant circuit 40) Since the second compressor 41 is not driven, the second refrigerant does not circulate through the second refrigerant circuit 40 during cooling operation.

[0080] (heat medium circuit 50) The circulation pump 51 draws in the heat transfer medium circulating in the heat transfer medium circuit 50 from the suction port 51a and discharges it from the discharge port 51b. The discharged heat transfer medium flows into the third flow path 130 of the heat exchanger 100 from one end 130a. The heat transfer medium that flows into the third flow path 130 releases heat to the first refrigerant passing through the first flow path 110. The heat transfer medium that has flowed out of the third flow path 130 flows into the fourth flow path 140 from one end 140a. As described above, since the second refrigerant does not circulate in the second refrigerant circuit 40, the heat transfer medium does not substantially exchange heat with the second refrigerant in the fourth flow path 140. The heat transfer medium that has flowed out of the fourth flow path 140 flows into the utilization heat exchangers 52a and 52b. The heat transfer medium that has flowed into the utilization heat exchanger 52a absorbs heat from the water stored in the tank 53. The heat transfer medium flowing into the heat exchanger 52b absorbs heat from the air in the space being air-conditioned. In other words, the heat transfer medium flowing into the heat exchanger 52a cools the water stored in the tank 53, and the heat transfer medium flowing into the heat exchanger 52b cools the air in the space being air-conditioned. The heat transfer medium flowing out from the heat exchangers 52a and 52b is drawn back into the circulation pump 51 from the suction port 31a.

[0081] (2) Heat exchanger 100 (2-1) Overall structure Figure 2 is a perspective view of the heat exchanger 100. The heat exchanger 100 is a plate heat exchanger in which multiple flow channels c (first flow channel 110, second flow channel 120, third flow channel 130, fourth flow channel 140, fifth flow channel 150, and sixth flow channel 160) formed by stacking multiple metal plates processed into a predetermined shape are housed inside a casing 200. In Figure 2, for convenience, a portion of the casing 200 is shown as transparent.

[0082] As shown in Figure 2, the casing 200 is a rectangular parallelepiped with a depth (thickness) smaller than its height and width. The casing 200 has two main surfaces 210 and four side surfaces 220. In plan view, the main surfaces 210 are formed in a rectangular shape, with one side longer than the other. The casing 200 is provided with a group of flow pipes 230 on the side surfaces 220 that communicate with the interior. The heat exchanger 100 is positioned such that the first end E1 is located vertically below the second end E2.

[0083] The circulating pipe group 230 includes a first circulating pipe 231, a second circulating pipe 232, a third circulating pipe 233, a fourth circulating pipe 234, a fifth circulating pipe 235, a sixth circulating pipe 236, a seventh circulating pipe 237, and an eighth circulating pipe 238. One end of each of the circulating pipe group 230 is connected to the end of the flow path c.

[0084] The casing 200 houses a first layer L1 and a second layer L2, each having multiple flow channels c arranged on the same plane. The first layer L1 and the second layer L2 are stacked on top of each other inside the casing 200. The heat exchanger 100 causes heat exchange to occur between the fluids flowing through the first layer L1 (first refrigerant, second refrigerant) and the fluids flowing through the second layer L2 (heat transfer medium).

[0085] In the following, the structure of the flow path c contained in the first layer L1 and the second layer L2 will be explained with reference to Figure 3, which is a plan view of the first layer L1, and Figure 4, which is a plan view of the second layer L2, as seen from the direction indicated by arrow A in Figure 2. Figures 3 and 4 show the flow of the first refrigerant, the second refrigerant, and the heat transfer medium in heating operation with dotted lines.

[0086] For convenience, in the following explanation, the direction in which the long side of the main surface 210 extends will be referred to as the first direction D1, and the direction in which the short side of the main surface 210 extends will be referred to as the second direction D2. In addition, in the plan view of the first layer L1 and the second layer L2, the two edges that overlap the long side of the main surface 210 will be referred to as the first edge E1 and the second edge E2, respectively, and the two edges that overlap the short side will be referred to as the third edge E3 and the fourth edge E4, respectively.

[0087] (2-2) Detailed Configuration (2-2-1) 1st layer L1 The first layer L1 consists of a first channel 110, a second channel 120, a fifth channel 150, and a first connecting channel 170a, all arranged on the same plane. For convenience, in the following description, the first layer L1 will be described by dividing it into three rectangular regions, the first part P1, the second part P2, and the fifth part P5, which are aligned along the second direction D2 in a plan view.

[0088] As shown in Figure 3, the second portion P2 is the region where one side touches the third end E3. The fifth portion P5 is the region where one side touches the fourth end E4. The second portion P2 is the region located between the second portion P2 and the fifth portion P5.

[0089] (2-2-1-1) 1st part P1 The first part P1 includes a first channel 110 and a first connecting channel 170a.

[0090] As described above, the first flow path 110 is the flow path c through which the first refrigerant flows. As shown in Figure 3, the first flow path 110 has four first directional extensions 111 and five second directional extensions 112.

[0091] The second direction extension portion 112 is the portion that extends along the second direction D2. The second direction extension portions 112 are formed to be arranged along the first direction D1 at predetermined intervals. In the following description, when it is necessary to distinguish between the five second direction extension portions 112, they will be referred to as second direction extension portion 112a, second direction extension portion 112b, second direction extension portion 112c, second direction extension portion 112d, and second direction extension portion 112e, respectively, from the first end E1 side to the second end E2 side.

[0092] The end of the second directional extension 112a on the third end E3 side is the other end 110b of the first flow channel 110. The other end 110b communicates with the seventh flow pipe 237. The end of the second directional extension 112e on the fourth end E4 side is one end 110a of the first flow channel 110. One end 110a communicates with the first connecting flow channel 170a.

[0093] The first directional extension 111 is the portion that extends along the first direction D1. The first directional extension 111 connects one end of two adjacent second directional extensions 112 so that they communicate with each other. In the following description, when it is necessary to distinguish between the four first directional extensions 111, they will be referred to as first directional extension 111a, first directional extension 111b, first directional extension 111c, and first directional extension 111d, respectively, from the first end E1 to the second end E2.

[0094] The second directional extension 112a and the second directional extension 112b are in communication via the first directional extension 111a connected to the end on the fourth end E4 side. The second directional extension 112b and the second directional extension 112c are in communication via the first directional extension 111c connected to the end on the third end E3 side. The second directional extension 112c and the second directional extension 112d are in communication via the first directional extension 111b connected to the end on the fourth end E4 side. The second directional extension 112d and the second directional extension 112e are in communication via the first directional extension 111d connected to the end on the third end E3 side.

[0095] The first connecting channel 170a is formed to extend in the first direction D1. The first connecting channel 170a is formed to be adjacent to the first channel 110 on the fourth end E4 side. The end of the first connecting channel 170a on the second end E2 side is connected to one end 110a of the first channel 110, and the end on the first end E1 side is connected to the other end 150b of the fifth channel 150. The first connecting channel 170a may also be provided in the second section P2 described later.

[0096] (2-2-1-2) Second part P2 The second part P2 includes the second flow path 120.

[0097] As described above, the second flow path 120 is the flow path c through which the second refrigerant flows. As shown in Figure 3, the second flow path 120 has four first-direction extensions 121 and five second-direction extensions 122.

[0098] The second direction extension portion 122 is the portion that extends along the second direction D2. The second direction extension portions 122 are formed to be arranged along the first direction D1 at predetermined intervals. In the following description, when it is necessary to distinguish between the five second direction extension portions 122, they will be referred to as second direction extension portion 122a, second direction extension portion 122b, second direction extension portion 122c, second direction extension portion 122d, and second direction extension portion 122e, respectively, from the first end E1 side to the second end E2 side.

[0099] The end of the second directional extension 122a on the fourth end E4 side is the other end 120b of the second flow channel 120. The other end 120b communicates with the sixth flow pipe 236. The end of the second directional extension 122e on the third end E3 side is the one end 120a of the second flow channel 120. The one end 120a communicates with the first flow pipe 231.

[0100] The first directional extension 121 is the portion that extends along the first direction D1. The first directional extension 121 connects one end of two adjacent second directional extensions 122 so as to communicate with each other. In the following description, when it is necessary to distinguish between the four first directional extensions 121, they will be referred to as first directional extension 121a, first directional extension 121b, first directional extension 121c, and first directional extension 121d, respectively, from the first end E1 to the second end E2.

[0101] The second directional extension 122a and the second directional extension 122b are in communication via the first directional extension 121a connected to the end on the third end E3 side. The second directional extension 122b and the second directional extension 122c are in communication via the second directional extension 122c connected to the end on the fourth end E4 side. The second directional extension 122c and the second directional extension 122d are in communication via the first directional extension 121b connected to the end on the third end E3 side. The second directional extension 122d and the second directional extension 122e are in communication via the second directional extension 122d connected to the end on the fourth end E4 side.

[0102] (2-2-1-3) 5th part P5 The fifth part P5 includes the fifth channel 150.

[0103] As described above, the fifth flow path 150 is the flow path c through which the first refrigerant flows. As shown in Figure 3, the fifth flow path 150 has four first-direction extensions 151 and five second-direction extensions 152.

[0104] The second direction extension portion 152 is the portion that extends along the second direction D2. The second direction extension portions 152 are formed to be arranged along the first direction D1 at predetermined intervals. In the following description, when it is necessary to distinguish between the five second direction extension portions 152, they will be referred to as second direction extension portion 152a, second direction extension portion 152b, second direction extension portion 152c, second direction extension portion 152d, and second direction extension portion 152e, starting from the first end E1 and moving towards the second end E2.

[0105] The end of the second directional extension 152a on the third end E3 side is one end 150a of the fifth flow channel 150. One end 150a communicates with the first connecting flow channel 170a. The end of the second directional extension 152e on the fourth end E4 side is the other end 150b of the fifth flow channel 150. The other end 150b communicates with the fourth flow pipe 234.

[0106] The first directional extension 151 is the portion that extends along the first direction D1. The first directional extension 151 connects one end of two adjacent second directional extensions 152 so that they communicate with each other. In the following description, when it is necessary to distinguish between the four first directional extensions 151, they will be referred to as first directional extension 151a, first directional extension 151b, first directional extension 151c, and first directional extension 151d, respectively, from the first end E1 to the second end E2.

[0107] The second directional extension 152a and the second directional extension 152b are in communication via the first directional extension 151a connected to the end on the fourth end E4 side. The second directional extension 152b and the second directional extension 152c are in communication via the first directional extension 151c connected to the end on the third end E3 side. The second directional extension 152c and the second directional extension 152d are in communication via the first directional extension 151b connected to the end on the fourth end E4 side. The second directional extension 152d and the second directional extension 152e are in communication via the first directional extension 151d connected to the end on the third end E3 side.

[0108] (2-2-2) 2nd layer L2 The second layer L2 consists of a third channel 130, a fourth channel 140, a sixth channel 160, and a second connecting channel 170b, all arranged on the same plane. For convenience, in the following description, the second layer L2 will be described by dividing it into three rectangular regions, the third part P3, the fourth part P4, and the sixth part P6, which are aligned along the second direction D2 in a plan view.

[0109] As shown in Figure 4, the third portion P3 is the region where one side touches the third end E3. The sixth portion P6 is the region where one side touches the fourth end E4. The fourth portion P4 is the region located between the third portion P3 and the sixth portion P6.

[0110] (2-2-2-1) Third part P3 The third part P3 has the same shape and size as the second part P2 in plan view. The third part P3 is stacked on the second part P2 with the second layer L2 stacked on the first layer L1, and is formed so that its edge overlaps with the edge of the second part P2. The third part P3 includes a third channel 130 and a second connecting channel 170b.

[0111] As described above, the third channel 130 is channel c through which the heat transfer medium flows. As shown in Figure 3, the third channel 130 has three first-direction extensions 131 and five second-direction extensions 132.

[0112] The second direction extension portion 132 is the portion that extends along the second direction D2. The second direction extension portions 132 are formed to be arranged along the first direction D1 at predetermined intervals. In the following description, when it is necessary to distinguish between the five second direction extension portions 132, they will be referred to as second direction extension portion 132a, second direction extension portion 132b, second direction extension portion 132c, second direction extension portion 132d, and second direction extension portion 132e, respectively, from the first end E1 side to the second end E2 side.

[0113] The end of the second directional extension 132a on the third end E3 side is one end 130a of the third flow channel 130. One end 130a communicates with the second connecting flow channel 170b. The end of the second directional extension 132e on the fourth end E4 side is the other end 130b of the third flow channel 130. The other end 130b communicates with the second flow pipe 232.

[0114] The first directional extension 131 is the portion that extends along the first direction D1. The first directional extension 131 connects one end of two adjacent second directional extensions 132 so that they communicate with each other. In the following description, when it is necessary to distinguish between the four first directional extensions 131, they will be referred to as first directional extension 131a, first directional extension 131b, first directional extension 131c, and first directional extension 131d, respectively, from the first end E1 to the second end E2.

[0115] The second directional extension 132a and the second directional extension 132b are in communication via the first directional extension 131a connected to the end on the fourth end E4 side. The second directional extension 132b and the second directional extension 132c are in communication via the second directional extension 132c connected to the end on the third end E3 side. The second directional extension 132c and the second directional extension 132d are in communication via the first directional extension 131b connected to the end on the fourth end E4 side. The second directional extension 132d and the second directional extension 132e are in communication via the second directional extension 132d connected to the end on the third end E3 side.

[0116] The second connecting channel 170b is formed to extend in the first direction D1. The second connecting channel 170b is formed to be adjacent to the third channel 130 on the third end E3 side. The end of the second connecting channel 170b on the second end E2 side is connected to the other end 140b of the fourth channel 140, and the end on the first end E1 side is connected to one end 130a of the third channel 130. The second connecting channel 170b may be provided in the fourth section P4 described later.

[0117] (2-2-2-2) 4th part P4 The fourth part P4 has the same shape and size as the first part P1 in plan view. The fourth part P4 is laminated on the first part P1 with the second layer L2 laminated on the first layer L1, and its edges are formed to overlap with the edges of the first part P1.

[0118] As described above, the fourth channel 140 is channel c through which the heat transfer medium flows. As shown in Figure 4, the fourth channel 140 has four first-direction extensions 141 and five second-direction extensions 142.

[0119] The second direction extension portion 142 is the portion that extends along the second direction D2. The second direction extension portions 142 are formed to be arranged along the first direction D1 at predetermined intervals. In the following description, when it is necessary to distinguish between the five second direction extension portions 142, they will be referred to as second direction extension portion 142a, second direction extension portion 142b, second direction extension portion 142c, second direction extension portion 142d, and second direction extension portion 142e, starting from the first end E1 and moving towards the second end E2.

[0120] The end of the second directional extension 142a on the third end E3 side is one end 140a of the fourth flow channel 140. One end 140a communicates with the fifth flow pipe 235. The end of the second directional extension 142e on the fourth end E4 side is the other end 140b of the fourth flow channel 140. The other end 140b communicates with the second connecting flow channel 170b.

[0121] The first directional extension 141 is the portion that extends along the first direction D1. The first directional extension 141 connects one end of two adjacent second directional extensions 142 so as to communicate with each other. In the following description, when it is necessary to distinguish between the four first directional extensions 141, they will be referred to as first directional extension 141a, first directional extension 141b, first directional extension 141c, and first directional extension 141d, respectively, from the first end E1 to the second end E2.

[0122] The second directional extension 142a and the second directional extension 142b are in communication via the first directional extension 141a connected to the end on the fourth end E4 side. The second directional extension 142b and the second directional extension 142c are in communication via the first directional extension 141c connected to the end on the third end E3 side. The second directional extension 142c and the second directional extension 142d are in communication via the first directional extension 141b connected to the end on the fourth end E4 side. The second directional extension 142d and the second directional extension 142e are in communication via the first directional extension 141d connected to the end on the third end E3 side.

[0123] (2-2-2-3) 6th part P6 The sixth section P6 has the same shape and size as the sixth section P6 in a plan view. The sixth section P6 is stacked on the fifth section P5 with the second layer L2 stacked on the first layer L1, and is formed so that its edge overlaps with the edge of the fifth section P5. The sixth section P6 includes the sixth channel 160.

[0124] As described above, the sixth flow path 160 is the flow path c through which the second refrigerant flows. As shown in Figure 4, the sixth flow path 160 has four first-direction extensions 161 and five second-direction extensions 162.

[0125] The second direction extension portion 162 is the portion that extends along the second direction D2. The second direction extension portions 162 are formed to be arranged along the first direction D1 at predetermined intervals. In the following description, when it is necessary to distinguish between the five second direction extension portions 162, they will be referred to as second direction extension portion 162a, second direction extension portion 162b, second direction extension portion 162c, second direction extension portion 162d, and second direction extension portion 162e, starting from the first end E1 and moving towards the second end E2.

[0126] The end of the second extension section 162a on the fourth end E4 side is one end 160a of the sixth flow channel 160. One end 160a communicates with the eighth flow pipe 238. The end of the second extension section 162e on the third end E3 side is the other end 160b of the sixth flow channel 160. The other end 160b communicates with the third flow pipe 233.

[0127] The first directional extension 161 is the portion that extends along the first direction D1. The first directional extension 161 connects one end of two adjacent second directional extensions 162 so that they communicate with each other. In the following description, when it is necessary to distinguish between the four first directional extensions 161, they will be referred to as first directional extension 161a, first directional extension 161b, first directional extension 161c, and first directional extension 161d, respectively, from the first end E1 to the second end E2.

[0128] The second directional extension 162a and the second directional extension 162b are in communication via the first directional extension 161a connected to the end on the third end E3 side. The second directional extension 162b and the second directional extension 162c are in communication via the first directional extension 161c connected to the end on the fourth end E4 side. The second directional extension 162c and the second directional extension 162d are in communication via the first directional extension 161b connected to the end on the third end E3 side. The second directional extension 162d and the second directional extension 162e are each in communication via the first directional extension 161d connected to the end on the fourth end E4 side.

[0129] (2-3) Flow of the first refrigerant, the second refrigerant, and the heat transfer medium Next, we will describe the flow of the first refrigerant, the second refrigerant, and the heat transfer medium in the heat exchanger 100 during the heating operation of the refrigeration unit 1.

[0130] (2-3-1) First refrigerant During the heating operation of the refrigeration unit 1, the first refrigerant circulating in the first refrigerant circuit 30 flows into the heat exchanger 100 through the fourth flow pipe 234, and then flows into the fifth flow path 150 from one end 150a.

[0131] The first refrigerant that flows into the fifth flow path 150 flows through one end 150a, the second directional extension section 152e, the first directional extension section 151d, the second directional extension section 152d, the first directional extension section 151c, the second directional extension section 152c, the first directional extension section 151b, the second directional extension section 152b, the first directional extension section 151a, and the second directional extension section 152a in this order, and then flows out from the other end 150b. In other words, in the fifth section P5, the first refrigerant flows through the fifth flow path 150 in a meandering manner from the second end E2 side to the first end E1 side.

[0132] The first refrigerant that flows out from the other end 150b of the fifth flow path 150 flows into the first connecting flow path 170a. The first refrigerant that flows into the first connecting flow path 170a flows from the first end E1 side to the second end E2 side in the first connecting flow path 170a, and then flows into the first flow path 110 from one end 110a.

[0133] The first refrigerant that flows into the first flow path 110 flows through one end 110a, the second extension section 112e, the first extension section 111d, the second extension section 112d, the first extension section 111c, the second extension section 112c, the first extension section 111b, the second extension section 112b, the first extension section 111a, and the second extension section 112a in this order, and then flows out from the other end 110b. In other words, in the first section P1, the first refrigerant flows through the first flow path 110 in a meandering manner from the second end E2 side to the first end E1 side.

[0134] The first refrigerant that flows out from the other end 110b of the first flow path 110 flows out of the heat exchanger 100 through the seventh flow pipe 237.

[0135] Thus, in the first section P1 and the fifth section P5, the first refrigerant flows in the order of the fifth flow path 150, the first connecting flow path 170a, and the first flow path 110. In addition, in a plan view of the first layer L1, the first refrigerant flows through the first flow path 110 in a direction opposite to the direction in which the heat transfer medium flows (described later). The heat exchanger 100 is equipped with a first connecting flow path 170a through which the first refrigerant flows from the first end E1 to the second end E2. Therefore, the first refrigerant can flow from the second end E2 to the first end E1 through both the fifth flow path 150 and the first flow path 110.

[0136] (2-3-2) Second refrigerant During the heating operation of the refrigeration system 1, the second refrigerant discharged from the second compressor 41, which circulates in the second refrigerant circuit 40, flows into the heat exchanger 100 through the first flow pipe 231, and then flows into the second flow path 120 from one end 120a.

[0137] The second refrigerant that flows into the second flow path 120 flows through one end 120a, the second directional extension section 122e, the first directional extension section 121d, the second directional extension section 122d, the first directional extension section 121c, the second directional extension section 122c, the first directional extension section 121b, the second directional extension section 122b, the first directional extension section 121a, and the second directional extension section 122a in this order, and then flows out from the other end 120b. In other words, in the second section P2, the second refrigerant flows through the second flow path 120 in a meandering manner from the second end E2 side to the first end E1 side.

[0138] The second refrigerant that flows out from the other end 120b of the second flow path 120 flows out of the heat exchanger 100 through the sixth flow pipe 236.

[0139] Thus, the second refrigerant flows through the second channel 120 in a direction opposite to the direction in which the heat transfer medium flows (described later) when viewed in plan of the first layer L1.

[0140] During the heating operation of the refrigeration unit 1, the second refrigerant that flows out of the expansion mechanism 42 from the second refrigerant circuit 40 flows into the heat exchanger 100 through the eighth flow pipe 238, and then flows into the sixth flow path 160 from one end 160a.

[0141] The heat transfer fluid that flows into the sixth flow path 160 flows through one end 160a, the second direction extension section 162a, the first direction extension section 161a, the second direction extension section 162b, the first direction extension section 161b, the second direction extension section 162c, the first direction extension section 161c, the second direction extension section 162d, the first direction extension section 161d, and the second direction extension section 162e in this order, and then flows out from the other end 160b. In other words, in the sixth section P6, the heat transfer fluid flows through the sixth flow path 160 in a meandering manner from the first end E1 side to the second end E2 side.

[0142] The second refrigerant that flows out from the other end 160b of the sixth flow path 160 flows out of the heat exchanger 100 through the third flow pipe 233.

[0143] Thus, the second refrigerant flows through the sixth flow path 160 in a direction opposite to the direction in which the first refrigerant flows, in a plan view of the second layer L2.

[0144] (2-3-3)Heating medium During the heating operation of the refrigeration unit 1, the heat transfer medium circulating in the heat transfer medium circuit 50 flows into the heat exchanger 100 through the fifth flow pipe 235, and then flows into the third flow path 130 from one end 130a.

[0145] The heat transfer fluid that flows into the third flow path 130 flows through one end 130a, the second direction extension section 132a, the first direction extension section 131a, the second direction extension section 132b, the first direction extension section 131b, the second direction extension section 132c, the first direction extension section 131c, the second direction extension section 132d, the first direction extension section 131d, and the second direction extension section 132e in this order, and then flows out from the other end 130b. In other words, in the third section P3, the heat transfer fluid flows through the third flow path 130 in a meandering manner from the first end E1 side to the second end E2 side.

[0146] The heat transfer fluid that flows out from the other end 130b of the third flow path 130 flows into the second connecting flow path 170b. The heat transfer fluid that flows into the second connecting flow path 170b flows from the second end E2 side to the first end E1 side, and then flows into the fourth flow path 140 from one end 140a.

[0147] The heat transfer fluid that flows into the fourth channel 140 flows through one end 140a, the second direction extension section 142a, the first direction extension section 141a, the second direction extension section 142b, the first direction extension section 141b, the second direction extension section 142c, the first direction extension section 141c, the second direction extension section 142d, the first direction extension section 141d, and the second direction extension section 142e in this order, and then flows out from the other end 140b. In other words, in the fourth section P4, the heat transfer fluid flows through the fourth channel 140 in a meandering manner from the first end E1 side to the second end E2 side.

[0148] The heat transfer fluid that flows out from the other end 140b of the fourth flow path 140 flows out of the heat exchanger 100 through the second flow pipe 232.

[0149] Thus, the heat transfer fluid flows through the third section P3 and then through the fourth section P4. In other words, the heat transfer fluid flows in the order of the third channel 130, the second connecting channel 170b, and the fourth channel 140.

[0150] As described above, the heat transfer medium flowing into the third flow path 130 absorbs heat from the first refrigerant passing through the first flow path 110 during heating operation. Therefore, the temperature of the heat transfer medium at the other end 130b, which is the outlet of the third section P3, is higher than the temperature of the heat transfer medium at the one end 130a, which is the inlet of the third section P3. Similarly, the heat transfer medium flowing into the fourth flow path 140 absorbs heat from the second refrigerant passing through the second flow path 120 during heating operation. Therefore, the temperature of the heat transfer medium at the other end 140b, which is the outlet of the fourth section P4, is higher than the temperature of the heat transfer medium at the one end 140a, which is the inlet of the fourth section P4.

[0151] The first refrigerant passing through the first flow path 110 absorbs heat from the heat transfer medium flowing into the third flow path 130. In this case, in the installed state of the heat exchanger 100, it is preferable that the first direction D1 is along the vertical up-down direction, with the first end being the lower end and the second end being the upper end. Specifically, it is preferable that the first refrigerant flows vertically upward (towards the second end E2) to vertically downward (towards the first end E1) in the first flow path 110. Furthermore, the second refrigerant passing through the second flow path 120 absorbs heat from the heat transfer medium flowing into the fourth flow path 140. In this case, it is preferable that the second refrigerant flows vertically upward (towards the second end E2) to vertically downward (towards the first end E1) in the second flow path 120.

[0152] Furthermore, the heat transfer medium flows through the third channel 130 in a direction opposite to the direction in which the first refrigerant flows, in a plan view of the second layer L2. The heat transfer medium also flows through the fourth channel 140 in a direction opposite to the direction in which the second refrigerant flows, in a plan view of the second layer L2.

[0153] The heat exchanger 100 is equipped with a second connecting channel 170b through which the heat transfer medium flows from vertically upward (towards the second end E2) to vertically downward (towards the first end E1). Therefore, the heat transfer medium can flow from vertically downward (towards the first end E1) to vertically upward (towards the second end E2) through both the third channel 130 and the fourth channel 140.

[0154] (2-3-4) Regarding Layer 1 L1 and Layer 2 L2 As explained above, the first layer L1 is separated into a first section P1 and a fifth section P5 through which the first refrigerant flows, and a second section P2 through which the second refrigerant flows. The second layer L2 is separated into a third section P3 and a fourth section P4 through which the heat transfer medium flows, and a sixth section P6 through which the second refrigerant flows.

[0155] (4) Features (4-1) The heat exchanger 100 is composed of multiple stacked layers. The heat exchanger 100 comprises a first layer L1 and a second layer L2 stacked on the first layer L1. The first layer L1 is separated into a first section P1 through which the first refrigerant flows and a second section P2 through which the second refrigerant flows. The second layer L2 has a third section and a fourth section. The third section P3 overlaps with the second section P2 in a plan view and is the section through which the heat transfer medium flows. The fourth section overlaps with the first section P1 in a plan view and is the section through which the heat transfer medium flows. The heat transfer medium flows through the third section P3 and then through the fourth section P4.

[0156] In the first layer L1 of the heat exchanger 100, the first refrigerant and the second refrigerant flow through the first and second parts P1 and P2, respectively, which are separated from each other. In the second layer L2 of the heat exchanger 100, the heat transfer medium flows through the third part P3, which overlaps with the second part P2, and the fourth part P4, which overlaps with the first part P1. As a result, the heat exchanger 100 can exchange heat between the first refrigerant and the heat transfer medium, and between the second refrigerant and the heat transfer medium. Furthermore, since the first part P1 and the second part P2 and the third part P3 and the fourth part P4 are each formed in a single layer, and these layers are stacked, the size of the heat exchanger 100 is suppressed.

[0157] Therefore, the heat exchanger 100 can enable heat exchange between multiple fluids while suppressing its size.

[0158] (4-2) The temperature of the heat transfer medium at the other end 130b of the third section P3 is higher than the temperature of the heat transfer medium at one end 130a of the third section P3. The temperature of the heat transfer medium at the other end 140b of the fourth section P4 is higher than the temperature of the heat transfer medium at one end 140a of the fourth section P4.

[0159] As a result, in the heat exchanger 100, the heat transfer medium is heated by exchanging heat with the first fluid and the second fluid.

[0160] (4-3) The first section P1 has a first flow path 110 through which the first refrigerant flows. The second section P2 has a second flow path 120 through which the second refrigerant flows. The third section P3 has a third flow path 130 through which the heat transfer medium flows. The fourth section P4 has a fourth flow path 140 through which the heat transfer medium flows. The heat transfer medium flows through the third flow path 130 from the first end E1, which is one end in a predetermined first direction D1, to the second end E2, which is the other end in the first direction D1. In a plan view of the first layer L1, the second refrigerant flows through the second flow path 120 in a direction opposite to the direction in which the heat transfer medium flows.

[0161] As a result, the heat exchanger 100 can exchange heat more efficiently between the second refrigerant and the heat transfer medium.

[0162] (4-4) The heat transfer fluid flows through the fourth channel 140 from the first end E1 to the second end E2. The first refrigerant flows through the first channel 110 in a direction opposite to the direction in which the heat transfer fluid flows, in a plan view of the first layer L1.

[0163] As a result, the heat exchanger 100 can exchange heat more efficiently between the first refrigerant and the heat transfer medium.

[0164] (4-5) The third part P3 and the fourth part P4 are aligned along the second direction D2, which is perpendicular to the first direction D1, in a plan view of the second layer L2. The second layer L2 further has a second connecting channel 170b that connects the third channel 130 and the fourth channel 140. The heat transfer medium flows in the order of the third channel 130, the second connecting channel 170b, and the fourth channel 140, and flows through the second connecting channel 170b from the second end E2 side toward the first end E1 side.

[0165] (4-6) The heat transfer fluid flows through the third flow path 130 along the second direction D2, from the third end E3, which is one end in the second direction D2, to the fourth end E4, which is the other end in the second direction D2. The heat transfer fluid then flows along the first direction D1 from the first end E1 to the second end E2, then along the second direction D2 from the fourth end E4 to the third end E3, and then along the first direction D1 from the first end E1 to the second end E2.

[0166] (4-7) The first and second refrigerants are refrigerants. The heat transfer medium is water. The first end E1 is located vertically below the second end E2.

[0167] (4-8) The first layer L1 further has a fifth section P5 through which the first refrigerant flowing through the first section P1 flows. The second layer L2 is stacked on the fifth section P5 and further has a sixth section P6 through which the second refrigerant flows.

[0168] The heat exchanger 100 can further exchange heat between the first refrigerant flowing through the fifth section P5 and the second refrigerant flowing through the sixth section P6.

[0169] (4-9) The refrigeration system 1 includes a heat exchanger 100.

[0170] By suppressing the enlargement of the heat exchanger 100, the enlargement of the refrigeration system 1 is also suppressed.

[0171] (5) Variant (5-1) Variation 1 The shape of the third flow path 130 is not limited to the configuration of the first embodiment.

[0172] Figure 5 is a plan view of the second layer L2 of the heat exchanger 100 according to Modification 1. As shown in Figure 5, the third flow path 130 of the heat exchanger 100 according to Modification 1 has five first-direction extensions 131 and two second-direction extensions 132. The number of first-direction extensions 131 is just an example and is not limited to five.

[0173] Specifically, as shown in Figure 5, the second directional extension 132 is provided so as to be in contact with the edges of the first end E1 and the second end E2 in the third portion P3. The five first directional extensions 131 are arranged in the second direction D2 at predetermined intervals. Each of the first directional extensions 131 has both ends connected to each of the two second directional extensions 132.

[0174] One end 130a is formed at the end of the second directional extension 132 on the third end E3 side, which is provided so as to be in contact with the edge on the first end E1 side. The other end 130b is formed at the end of the second directional extension 132 on the fourth end E4 side, which is provided so as to be in contact with the edge on the second end E2 side.

[0175] As shown in Figure 5, the heat transfer medium that flows in from one end 130a flows along the first direction D1 until it reaches the second direction extension 132, which is provided so as to be in contact with the second end E2, after flowing into the first direction extension 131.

[0176] Furthermore, the shape of the fourth channel 140 may be the same as the shape of the third channel 130.

[0177] (5-2) Modification 2 The shapes of the third channel 130 and the fourth channel 140 are not limited to the configuration of the first embodiment.

[0178] Figure 6 is a plan view of the second layer L2 of the heat exchanger 100 according to Modification 2. As shown in Figure 6, the heat exchanger 100 according to Modification 2 is arranged such that the third portion P3 is located vertically below the fourth portion P4 (in other words, the third end E3 is located vertically below the fourth end E4). Furthermore, the heat exchanger 100 according to Modification 2 does not have a second connecting channel 170b, and the third channel 130 has five first directional extensions 131 and one second directional extension 132, and the fourth channel 140 has five first directional extensions 141 and one second directional extension 142. The number of first directional extensions 131 and first directional extensions 141 is an example and is not limited to five.

[0179] Specifically, as shown in Figure 6, the second directional extension portion 132 is provided so as to be in contact with the edge on the third end E3 side (the vertical lower end of the third portion P3) in the third portion P3. The second directional extension portion 142 is provided so as to be in contact with the edge on the fourth end E4 side (the vertical upper end of the fourth portion P4) in the fourth portion P4.

[0180] Five first-direction extensions 131 are arranged in the second direction D2 at predetermined intervals. Each of the first-direction extensions 131 has its third end E3 side (vertically downward) connected to a second-direction extension 132, and its fourth end E4 side (vertically upward) connected to a first-direction extension 141. Five first-direction extensions 141 are arranged in the second direction D2 at the same intervals as the five first-direction extensions 131. Each of the first-direction extensions 141 has its fourth end E4 side connected to a second-direction extension 142, and its third end E3 side connected to a first-direction extension 131. The first-direction extensions 131 and 141, connected to each other, form a flow path extending along the first direction D1.

[0181] One end 130a is formed at the end of the second directional extension 132 on the first end E1 side, which is provided so as to be in contact with the edge on the third end E3 side. The other end 140b is formed at the end of the second directional extension 142 on the second end E2 side, which is provided so as to be in contact with the edge on the fourth end E4 side. The other end 130b and one end 140a are not formed.

[0182] As shown in Figure 6, the heat transfer fluid that flows in from one end 130a flows along the second direction D2 until it reaches the first direction extension section 141 after entering the second direction extension section 132. The heat transfer fluid that flows into the first direction extension section 141 flows along the first direction D1 (vertical up and down direction).

[0183] (5-3) Modification 3 The shape of the fourth flow channel 140 is not limited to the configuration of the first embodiment. Figure 7 is a plan view of the second layer L2 of the heat exchanger 100 according to Modification 3. As shown in Figure 7, the heat exchanger 100 according to Modification 3 differs from the heat exchanger 100 of the first embodiment in the position of the second connecting flow channel 170b and the first directional extension portion 141.

[0184] Specifically, the second directional extension portion 142a and the second directional extension portion 142b are in communication via the first directional extension portion 141a connected to the end on the third end E3 side. The second directional extension portion 142b and the second directional extension portion 142c are in communication via the first directional extension portion 141c connected to the end on the fourth end E4 side. The second directional extension portion 142c and the second directional extension portion 142d are in communication via the first directional extension portion 141b connected to the end on the third end E3 side. The second directional extension portion 142d and the second directional extension portion 142e are in communication via the first directional extension portion 141d connected to the end on the fourth end E4 side.

[0185] The end of the second directional extension 142a on the fourth end E4 side is the other end 140b of the fourth channel 140. The other end 140b communicates with the second connecting channel 170b. The end of the second directional extension 142e on the third end E3 side is one end 140a of the fourth channel 140. One end 140a communicates with the other end 130b of the third channel 130.

[0186] The second connecting channel 170b is formed adjacent to the fourth channel 140 on the fourth end E4 side. The end of the second connecting channel 170b on the first end E1 side is connected to the other end 140b of the fourth channel 140. The end of the second connecting channel 170b on the second end E2 side communicates with the second flow pipe 232.

[0187] As shown in Figure 7, the heat transfer fluid that flows into the fourth channel 140 flows through one end 140a, the second direction extension 142e, the first direction extension 141d, the second direction extension 142d, the first direction extension 141c, the second direction extension 142c, the first direction extension 141b, the second direction extension 142b, the first direction extension 141a, and the second direction extension 142a in this order, and then flows out from the other end 140b through the second connecting channel 170b. In other words, in the fourth section P4, the heat transfer fluid flows through the fourth channel 140 in a meandering manner from the second end E2 side to the first end E1 side.

[0188] <Second Embodiment> In the second embodiment, the heat exchanger 100 causes heat exchange to occur between the fluid flowing through the first layer L1 (first refrigerant, heat transfer medium) and the fluid flowing through the second layer L2 (second refrigerant).

[0189] The first flow path 110 of the first section P1 is a flow path c through which the first refrigerant flows. The second flow path 120 of the second section P2 is a flow path c through which the heat transfer medium flows. The third flow path 130 of the third section P3 is a flow path c through which the second refrigerant flows. The fourth flow path 140 of the fourth section P4 is a flow path c through which the second refrigerant flows. The fifth flow path 150 of the fifth section P5 is a flow path c through which the first refrigerant flows. The sixth flow path 160 of the sixth section P6 is a flow path c through which the heat transfer medium flows.

[0190] The heat exchanger 100 may be used such that the temperature of the second refrigerant at the other end 130b of the third section P3 is higher than the temperature of the second refrigerant at one end 130a of the third section P3, and the temperature of the second refrigerant at the other end 140b of the fourth section P4 is lower than the temperature of the second refrigerant at one end 140a of the fourth section P4.

[0191] Specifically, the heat exchanger 100 may be used such that the first refrigerant flows through the second flow path 120 and the sixth flow path 160, the second refrigerant flows through the third flow path 130 and the fourth flow path 140, and the heat transfer medium flows through the first flow path 110 and the fifth flow path 150.

[0192] Figure 8 is a schematic diagram of the refrigeration system 2 according to the second embodiment. In Figure 8, features that are the same as or corresponding to those in the first embodiment are denoted by the same reference numerals. The difference between refrigeration system 1 and refrigeration system 2 lies in the connection relationships in the first refrigerant circuit 30, the second refrigerant circuit 40, and the heat transfer medium circuit 50 of the flow path c.

[0193] More specifically, the first flow path 110 of the heat exchanger 100 has one end 110a connected to the other end 150b of the fifth flow path 150, and the other end 110b connected to one end 52aaa of the utilization heat exchanger 52a and one end 52ba of the utilization heat exchanger 52b. The second flow path 120 of the heat exchanger 100 has one end 120a connected to the indoor unit 20 side end of the connecting pipe 37a, and the other end 120b connected to one end 160a of the sixth flow path 160. The third flow path 130 of the heat exchanger 100 has one end 130a connected to the other end 42b of the expansion mechanism 42, and the other end 130b connected to the suction section 41a of the second compressor 41. The fourth flow path 140 of the heat exchanger 100 has one end 140a connected to the discharge section 41b of the second compressor 41, and the other end 140b connected to one end 42a of the expansion mechanism 42. The fifth flow path 150 of the heat exchanger 100 has one end 150a connected to the discharge section 51b of the circulation pump 51, and the other end 150b connected to one end 110a of the first flow path 110. The sixth flow path 160 of the heat exchanger 100 has one end 160a connected to the other end 120ab of the second flow path 120, and the other end 160b connected to the end of the connecting pipe 37b on the indoor unit 20 side.

[0194] The operation of each part of the refrigeration unit 2, as well as the flow of the first refrigerant, second refrigerant, and heat transfer medium, are the same and therefore will not be explained.

[0195] In the heat exchanger 100 according to the second embodiment, the second refrigerant flowing through the third section P3 is heated by heat exchange with the first refrigerant, and the second refrigerant flowing through the fourth section P4 is cooled by heat exchange with the heat transfer medium.

[0196] <Conclusion> While embodiments of this disclosure have been described above, it should be understood that various modifications to the form and details are possible without departing from the spirit and scope of this disclosure as described in the claims. [Explanation of symbols]

[0197] 1, 2: Refrigeration equipment 100: Heat exchanger 110: First channel 120: Second channel 130: Third channel 140: Fourth channel D1: 1st direction D2 :Second direction E1: 1st end E2: 2nd end E3: 3rd end E4: Fourth end L1: 1st layer L2: 2nd layer P1: 1st part P2 :Second part P3: 3rd part P4: 4th part P5: 5th part P6: 6th part [Prior art documents] [Patent Documents]

[0198] [Patent Document 1] Patent No. 2008-298407

Claims

1. A heat exchanger (100) composed of multiple stacked layers, The first layer (L1), The second layer (L2) is laminated on the first layer (L1) and Equipped with, The first layer (L1) is, It is separated into a first section (P1) through which the first fluid flows and a second section (P2) through which the second fluid flows. The second layer (L2) is, In a plan view, it overlaps with the first part (P1), and the third part (P3) through which the third fluid flows, In a plan view, it overlaps with the second portion (P2) and has a fourth portion (P4) through which the third fluid flows. The third fluid is, After flowing through the third section (P3), it flows through the fourth section (P4), Heat exchanger (100).

2. The temperature of the third fluid at the outlet of the third portion (P3) is higher than the temperature of the third fluid at the inlet of the third portion (P3). The temperature of the third fluid at the outlet of the fourth section (P4) is higher than the temperature of the third fluid at the inlet of the fourth section (P4). The heat exchanger (100) according to claim 1.

3. The first part (P1) is, Having a first flow path (110) through which the first fluid flows, The second part (P2) is, The device has a second flow path (120) through which the second fluid flows, The third part (P3) is, It has a third flow path (130) through which the third fluid flows, The aforementioned fourth part (P4) is, It has a fourth channel (140) through which the third fluid flows, The third fluid is, The third flow path (130) flows from the first end (E1), which is one end (42a) in a predetermined first direction (D1), to the second end (E2), which is the other end (42b) in the first direction (D1). The second fluid is In a plan view of the first layer (L1), the second flow channel (120) flows in a direction opposite to the direction in which the third fluid flows. The heat exchanger (100) according to claim 1.

4. The third fluid is, The fourth flow path (140) flows from the first end (E1) side to the second end (E2) side. The first fluid is In a plan view of the first layer (L1), the first flow channel (110) flows in a direction opposite to the direction in which the third fluid flows. The heat exchanger (100) according to claim 3.

5. The third part (P3) and the fourth part (P4) are, In a plan view of the second layer (L2), the elements are arranged along a second direction (D2) perpendicular to the first direction (D1), The second layer (L2) is, The device further includes a connecting channel (c) that connects the third channel (130) and the fourth channel (140), The third fluid is, The flow proceeds in the order of the third channel (130), the connecting channel (c), and the fourth channel (140). The connecting channel (c) flows from the second end (E2) side toward the first end (E1) side. The heat exchanger (100) according to claim 4.

6. The third channel (130) is Having a plurality of flow channels extending along the first direction (D1), The heat exchanger (100) according to claim 5.

7. The third fluid is, The third channel (130) is Along the second direction (D2), the flow is from the third end (E3), which is one end (42a) in the second direction (D2), toward the fourth end (E4), which is the other end (42b) in the second direction (D2). Subsequently, it flows along the first direction (D1) from the first end (E1) towards the second end (E2), Subsequently, it flows along the second direction (D2) from the fourth end (E4) side toward the third end (E3) side. Subsequently, it flows along the first direction (D1) from the first end (E1) towards the second end (E2), The heat exchanger (100) according to claim 5.

8. The third part (P3) is, Located vertically below the fourth portion (P4), The third fluid is, The third channel (130) and the fourth channel (140) flow along the vertical direction, The heat exchanger (100) according to claim 5.

9. The first fluid and the second fluid are It is a refrigerant, The third fluid is, It is water, The first end (E1) is Located vertically below the second end (E2), A heat exchanger (100) according to any one of claims 3 to 7.

10. The first layer (L1) is, The apparatus further comprises a fifth portion (P5) through which the first fluid, which flows through the first portion (P1), The second layer (L2) is, The fifth portion (P5) is further stacked with a sixth portion (P6) through which the second fluid flows, The heat exchanger (100) according to claim 1.

11. The third fluid is, The fourth flow path (140) flows from the second end (E2) side to the first end (E1) side. The first fluid is In a plan view of the first layer (L1), the first flow channel (110) flows in a direction opposite to the third fluid, The heat exchanger (100) according to claim 3.

12. The temperature of the third fluid at the outlet of the third portion (P3) is higher than the temperature of the third fluid at the inlet of the third portion (P3). The temperature of the third fluid at the outlet of the fourth portion (P4) is lower than the temperature of the third fluid at the inlet of the fourth portion (P4). The heat exchanger (100) according to claim 1.

13. The heat exchanger (100) described in claim 1 is provided. Refrigeration device (1).

Images