Heat exchanger and refrigeration device

Abstract

Provided is a heat exchanger that inhibits leakage of a refrigerant if water freezes and the volume thereof increases. This heat exchanger performs heat exchange between water and a refrigerant, and comprises: a first flow path through which water flows; a second flow path through which the refrigerant flows; partition walls; a first separation member; and a second separation member. The partition wall separates the first flow path and the second flow path. The first separation member is disposed at an end edge of the first flow path and separates two adjacent partition walls. The second separation member is disposed at an end edge of the second flow path and separates two adjacent partition walls. The first separation member is a material different from that of the second separation member and / or has a shape different from that of the second separation member.

Description

Heat exchangers and refrigeration equipment

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

[0002] BACKGROUND ART Plate-type heat exchangers are known in which a plurality of heat transfer plates are stacked at predetermined intervals to form flow paths for a first fluid and flow paths for a second fluid alternately in the stacking direction, thereby exchanging heat between the two fluids.

[0003] When a plate-type heat exchanger uses a refrigerant and water as fluids, the volume expansion of the frozen water can cause the heat transfer plates to break, resulting in the leakage of the refrigerant.Patent Document 1 (JP Patent Publication No. 10-132476) discloses, as a fifth embodiment, a heat exchanger equipped with heat transfer plates that can absorb stress through elastic deformation and prevent breakage even when the volume of frozen water expands.

[0004] Even with the heat transfer plate disclosed in Patent Document 1, there is a limit to the range in which stress can be absorbed (the range in which elastic deformation is possible), so damage to the heat transfer plate cannot be sufficiently prevented, and there is a risk of refrigerant leakage.

[0005] The present disclosure provides a heat exchanger and a refrigeration device that suppresses refrigerant leakage to the outside when water freezes and expands in volume.

[0006] A heat exchanger according to a first aspect is a heat exchanger for exchanging heat between water and a refrigerant, and includes a first flow path through which water flows, a second flow path through which the refrigerant flows, a partition wall, a first spacing member, and a second spacing member. The partition wall separates the first flow path from the second flow path. The first spacing member is disposed on an edge of the first flow path and separates two adjacent partition walls. The second spacing member is disposed on an edge of the second flow path and separates two adjacent partition walls. The first spacing member is made of a different material from the second spacing member and / or has a different shape from the second spacing member.

[0007] In this heat exchanger, when water flowing through the first flow path freezes and expands in volume, the first spacing member breaks before the second spacing member breaks. Therefore, with this heat exchanger, the second spacing member is prevented from breaking due to freezing of water flowing through the first flow path, and therefore the refrigerant flowing through the second flow path is prevented from leaking outside the heat exchanger.

[0008] A heat exchanger according to a second aspect is the heat exchanger according to the first aspect, wherein the material of the first spacing member has a smaller Young's modulus than the material of the second spacing member.

[0009] The first spacing member, which is made of a material with a smaller Young's modulus than the second spacing member, breaks before the second spacing member when water flowing through the first flow path freezes and expands in volume. Therefore, with this heat exchanger, breaking of the second spacing member due to freezing of water flowing through the first flow path is suppressed, and leakage of refrigerant flowing through the second flow path to the outside of the heat exchanger is suppressed.

[0010] A heat exchanger according to a third aspect is the heat exchanger according to the second aspect, wherein the first spacing member is made of copper or aluminum, and the second spacing member is made of stainless steel.

[0011] A heat exchanger according to a fourth aspect is the heat exchanger according to the first aspect, wherein the first spacing member has an outer surface formed with a recess recessed toward the first flow path.

[0012] When water flowing through the first flow path freezes and expands in volume, the first spacing member having the recessed portion breaks before the second spacing member does because stress concentrates in the recessed portion. Therefore, with this heat exchanger, the second spacing member is prevented from breaking due to freezing of water flowing through the first flow path, and therefore the refrigerant flowing through the second flow path is prevented from leaking outside the heat exchanger.

[0013] A heat exchanger according to a fifth aspect is the heat exchanger according to the first aspect, wherein the width of the first spacing member is narrower than the width of the second spacing member.

[0014] Because the width of the first spacing member is narrower than the width of the second spacing member, when the same pressure is generated in the first and second flow paths, a greater stress acts on the joint between the first spacing member and the partition wall than on the joint between the second spacing member and the partition wall. Therefore, when water flowing through the first flow path freezes and expands in volume, the joint between the first spacing member and the partition wall ruptures before the joint between the second spacing member and the partition wall. Therefore, with this heat exchanger, rupture of the second spacing member due to freezing of water flowing through the first flow path is suppressed, and therefore leakage of refrigerant flowing through the second flow path to the outside of the heat exchanger is suppressed.

[0015] A heat exchanger according to a sixth aspect is the heat exchanger according to the fifth aspect, wherein the joint between the second spacing member and the partition wall has a portion that overlaps with the first flow path when viewed in the stacking direction.

[0016] A heat exchanger according to a seventh aspect is the heat exchanger according to the sixth aspect, wherein the width of the first spacing member is equal to or less than half the width of the second spacing member.

[0017] A heat exchanger according to an eighth aspect is the heat exchanger according to the first aspect, wherein the first spacing member and the second spacing member are joined to the partition wall by using diffusion bonding.

[0018] A heat exchanger according to a ninth aspect is the heat exchanger according to any one of the first aspect to the eighth aspect, wherein the refrigerant is flammable or toxic.

[0019] This heat exchanger prevents the refrigerant from leaking from the heat exchanger even when a flammable or toxic refrigerant is used.

[0020] A refrigeration device according to a tenth aspect includes any one of the heat exchangers according to the first to ninth aspects.

[0021] 1 is a schematic diagram showing a refrigeration system 1 including a heat exchanger 100. FIG. 2 is a perspective view of the heat exchanger 100. FIG. 3 is an enlarged view of part A of FIG. 2. FIG. 4 is a cross-sectional view showing a first inner fin 110 housed in the heat exchanger 100. FIG. 5 is a cross-sectional view showing a second inner fin 120 housed in the heat exchanger 100. FIG. 6 is a cross-sectional view of the heat exchanger 100 of FIG. 3 taken along line BB'. FIG. 7 is a cross-sectional view of the heat exchanger 100 according to Modification A. FIG. 8 is a cross-sectional view of the heat exchanger 100 according to Modification B.

[0022] (1) Refrigeration Device 1 First, a refrigeration device 1 including a heat exchanger 100 according to an embodiment of the present disclosure will be described. The refrigeration device 1 heats or cools water supplied from outside the refrigeration device 1, such as city water (tap water), and supplies the water. The refrigeration device 1 has a water intake unit 1a, a water supply unit 1b, a heat exchanger 100, a refrigerant circuit 10, a water circuit 20, a water supply unit 30, and a control unit 40. Although not limited thereto, in this embodiment, the water supply unit 30 is installed indoors, and the water circuit 20 and the refrigerant circuit 10 are installed outdoors. As will be described in detail below, a refrigerant circulates in the refrigerant circuit 10, and water circulates in the water circuit 20.

[0023] The water intake section 1a takes water supplied from the outside into the refrigeration device 1. The water supply section 1b supplies water heated or cooled by the refrigeration device 1 to the outside.

[0024] (1-1) Heat Exchanger 100 The heat exchanger 100 exchanges heat between the refrigerant circulating through the refrigerant circuit 10 and the water circulating through the water circuit 20. The heat exchanger 100 has first flow pipes 170a and 170b, second flow pipes 180a and 180b, a first flow path 111, and a second flow path 121.

[0025] The first flow path 111 is a flow path through which water flows, and is provided between the first flow pipe 170a and the first flow pipe 170b.

[0026] The second flow path 121 is a flow path through which the refrigerant flows. The second flow path 121 is formed between the second flow pipe 180a and the second flow pipe 180b. The detailed structure of the heat exchanger 100 will be described later.

[0027] (1-2) Refrigerant Circuit 10 In the refrigerant circuit 10, a refrigerant is heated or cooled. The refrigerant circuit 10 is composed of a compressor 11, a four-way switching valve 12, a heat source heat exchanger 13, an expansion valve 14, and a second flow path 121 of the heat exchanger 100. The compressor 11, the four-way switching valve 12, the heat source heat exchanger 13, the expansion valve 14, and the second flow path 121 of the heat exchanger 100 are connected by piping, and the refrigerant circulates therethrough. In this embodiment, the refrigerant is propane.

[0028] The compressor 11 draws low-pressure refrigerant in the refrigerant circuit 10 through a suction port 11a, compresses it, and discharges it from a discharge port 11b as high-pressure refrigerant.

[0029] The four-way switching valve 12 has a first port P1, a second port P2, a third port P3, and a fourth port P4. Based on instructions from the control unit 40, the four-way switching valve 12 switches between a first state and a second state, in which the communication states of the first port P1, the second port P2, the third port P3, and the fourth port P4 are different. In the first state, the first port P1 and the second port P2 are communicated with each other, and the third port P3 and the fourth port P4 are communicated with each other. In the second state, the first port P1 and the fourth port P4 are communicated with each other, and the second port P2 and the third port P3 are communicated with each other.

[0030] The first port P1 is connected to the discharge portion 11b of the compressor 11. The second port P2 is connected to the second flow pipe 180a of the heat exchanger 100. The third port P3 is connected to the suction portion 11a of the compressor 11. The fourth port P4 is connected to one end of the heat source heat exchanger 13.

[0031] The heat source heat exchanger 13 exchanges heat between the refrigerant circulating through the refrigerant circuit 10 and a heat source (for example, outdoor air).

[0032] The expansion valve 14 adjusts the flow rate of the refrigerant circulating through the refrigerant circuit 10 and functions as a pressure reducing device that reduces the pressure of the refrigerant.

[0033] One end of the expansion valve 14 is connected to the other end of the heat source heat exchanger 13. The other end of the expansion valve 14 is connected to the second flow pipe 180b of the heat exchanger 100.

[0034] (1-3) Water Circuit 20 Water that has exchanged heat with the refrigerant circulates in the water circuit 20. The water circuit 20 is composed of the first flow path 111 of the heat exchanger 100, the water circulation pump 21, the flow rate adjustment valve 22, the first heat utilization heat exchanger 23, and the second heat utilization heat exchanger 24. The first flow path 111 of the heat exchanger 100, the water circulation pump 21, the flow rate adjustment valve 22, the first heat utilization heat exchanger 23, and the second heat utilization heat exchanger 24 are connected by piping, and water circulates inside.

[0035] The water circulation pump 21 circulates water inside the water circuit 20. The water circulation pump 21 draws water from the inside of the water circuit 20 through an intake port 21a and discharges the water from an outlet port 21b.

[0036] The intake port 21 a is connected to a first flow pipe 170 a of the heat exchanger 100. The discharge port 21 b is connected to one end of the flow rate adjustment valve 22.

[0037] The flow rate control valve 22 adjusts the flow rate of water circulating through the water circuit 20 .

[0038] The first utilization heat exchanger 23 exchanges heat between the water circulating through the water circuit 20 and the water stored inside a water storage tank 31 (described later) of the water supply unit 30. The first utilization heat exchanger 23 is disposed inside the water storage tank 31 so that the water passing through the inside can exchange heat with the water stored in the water storage tank 31.

[0039] One end of the first utilization heat exchanger 23 is connected to the other end of the flow rate adjustment valve 22. The other end of the first utilization heat exchanger 23 is connected to the first flow pipe 170b of the heat exchanger 100.

[0040] The second utilization heat exchanger 24 exchanges heat between the water circulating through the water circuit 20 and the air in the space to be air-conditioned (not shown). The second utilization heat exchanger 24 is disposed inside the space to be air-conditioned so that the water passing through the second utilization heat exchanger 24 can exchange heat with the air in the space to be air-conditioned.

[0041] One end of the second utilization heat exchanger 24 is connected to the discharge portion 21b of the water circulation pump 21. The other end of the second utilization heat exchanger 24 is connected to the first circulation pipe 170b of the heat exchanger 100.

[0042] The number of second utilization heat exchangers 24 included in the water circuit 20 may be one, or may be two or more as shown in FIG.

[0043] (1-4) Water Supply Unit 30 The water supply unit 30 exchanges heat between water supplied from outside the refrigeration apparatus 1 and water circulating in the water circuit 20, and then supplies the water to the outside of the refrigeration apparatus 1. The water supply unit 30 is composed of a water storage tank 31, a water supply pump 32, and a mixing valve 33. The water storage tank 31, the water supply pump 32, and the mixing valve 33 are connected by piping.

[0044] The water storage tank 31 stores water supplied from the outside. The stored water exchanges heat with water passing through the first usage heat exchanger 23. The water storage tank 31 takes in water supplied from the outside through the water inlet 31a and stores it. The stored water exchanges heat with water passing through the first usage heat exchanger 23 and is discharged from the water outlet 31b.

[0045] The water inlet 31a is connected to the water intake 1a to which water is supplied from the outside.

[0046] The water supply pump 32 draws in water stored in the water storage tank 31 and supplies it to the mixing valve 33. The water supply pump 32 draws in water from the water storage tank 31 through a suction port 32a and discharges the water from a discharge port 32b.

[0047] The intake port 32a is connected to the water outlet port 31b. The discharge port 32b is connected to a second port 33b (described later) of the mixing valve 33.

[0048] The mixing valve 33 mixes water supplied from the outside with water stored in the water storage tank 31. The mixing valve 33 has a first port 33a, a second port 33b, and a third port 33c.

[0049] The first port 33a is connected to a water intake section 1a to which water is supplied from the outside. The second port 33b is connected to a discharge section 32b of the water supply pump 32. The third port 33c is connected to a water supply section 1b that communicates with the outside of the refrigeration device 1.

[0050] (1-5) Control Unit 40 The control unit 40 controls the compressor 11, the four-way switching valve 12, the expansion valve 14, the water circulation pump 21, the flow rate control valve 22, the feedwater pump 32, and the mixing valve 33. Although not shown in the figure, the control unit 40 is electrically connected to the compressor 11, the four-way switching valve 12, the expansion valve 14, the water circulation pump 21, the flow rate control valve 22, the feedwater pump 32, and the mixing valve 33 so as to be able to send and receive control signals.

[0051] (1-6) Operation of Refrigeration Device 1 The refrigeration device 1 performs heating operation, cooling operation, and defrosting operation.

[0052] (1-6-1) Heating Operation Heating operation is an operation in which the refrigeration system 1 heats water supplied from the outside to the water intake unit 1a and supplies it from the water supply unit 1b. In heating operation, the control unit 40 sets the four-way switching valve 12 to the first state, drives the compressor 11, the water circulation pump 21, and the water supply pump 32, and controls the openings of the expansion valve 14, the flow rate control valve 22, and the mixing valve 33.

[0053] (1-6-1-1) Refrigerant Circuit 10 The compressor 11 draws low-pressure gas-phase refrigerant from the refrigerant circuit 10 through the suction port 11a and discharges it as high-pressure gas-phase refrigerant from the discharge port 11b. The high-pressure gas-phase refrigerant passes through the four-way switching valve 12, first through the first port P1 and then through the second port P2, and reaches the second flow path 121 of the heat exchanger 100. In the second flow path 121 of the heat exchanger 100, the high-pressure gas-phase refrigerant condenses into high-pressure liquid-phase refrigerant. At this time, the refrigerant releases heat to water passing through the first flow path 111. The high-pressure liquid-phase refrigerant reaches the expansion valve 14. The expansion valve 14, set to an appropriate opening, reduces the pressure of the high-pressure liquid-phase refrigerant to a low-pressure two-phase gas-liquid refrigerant. The low-pressure two-phase gas-liquid refrigerant evaporates in the heat-source heat exchanger 13 and becomes low-pressure gas-phase refrigerant. At this time, the refrigerant absorbs heat from the heat source (outside air). The low-pressure gas-phase refrigerant passes through the four-way switching valve 12 through the fourth port P4 and the third port P3 in this order, and is then drawn into the compressor 11 through the suction port 11a.

[0054] (1-6-1-2) Water Circuit 20 The water circulation pump 21 draws water circulating through the water circuit 20 from the suction port 21a and discharges it from the discharge port 21b. A portion of the discharged water passes through the flow rate adjustment valve 22 and reaches the first use heat exchanger 23. The water that has reached the first use heat exchanger 23 releases heat to the water stored in the water storage tank 31. In other words, the water that has reached the first use heat exchanger 23 heats the water stored in the water storage tank 31. A portion of the remaining water discharged from the water circulation pump 21 reaches the second use heat exchanger 24. The water that has reached the second use heat exchanger 24 releases heat to the air in the space to be air-conditioned. In other words, the water that has reached the second use heat exchanger 24 heats the air in the space to be air-conditioned. The water that has released heat in the first utilization heat exchanger 23 and the water that has released heat in the second utilization heat exchanger 24 reach the first flow path 111 of the heat exchanger 100. The water that has reached the first flow path 111 of the heat exchanger 100 absorbs heat from the refrigerant passing through the second flow path 121. The water that has absorbed the heat is drawn into the water circulation pump 21 from the suction portion 21 a.

[0055] (1-6-1-3) Water Supply Unit 30 Water stored in the water storage tank 31 is heated by absorbing heat from water passing through the first utilization heat exchanger 23. The water supply pump 32 draws in the water heated in the water storage tank 31 from the intake port 32a. The water drawn into the water supply pump 32 is discharged from the discharge port 32b to the mixing valve 33. The water discharged from the water supply pump 32 passes through the second port 33b and is mixed with water from the outside that has passed through the water intake unit 1a and reached the first port 33a. The water mixed in the mixing valve 33 passes through the third port 33c and is supplied to the outside of the refrigeration device 1 from the water supply unit 1b.

[0056] (1-6-2) Cooling Operation In cooling operation, the refrigeration system 1 cools water supplied from the outside to the water intake unit 1a and supplies the cooled water from the water supply unit 1b. In cooling operation, the control unit 40 sets the four-way switching valve 12 to the second state, drives the compressor 11, the water circulation pump 21, and the water supply pump 32, and controls the openings of the expansion valve 14, the flow rate control valve 22, and the mixing valve 33.

[0057] (1-6-2-1) Refrigerant Circuit 10 The compressor 11 draws low-pressure gas-phase refrigerant from the suction port 11a and discharges it as high-pressure gas-phase refrigerant from the discharge port 11b. The high-pressure gas-phase refrigerant passes through the four-way switching valve 12, first through the first port P1 and then through the fourth port P4, and reaches the heat-source heat exchanger 13. In the heat-source heat exchanger 13, the high-pressure gas-phase refrigerant condenses into high-pressure liquid-phase refrigerant. At this time, the refrigerant releases heat to the heat source (outside air). The high-pressure liquid-phase refrigerant reaches the expansion valve 14. The expansion valve 14, set to an appropriate opening, reduces the pressure of the high-pressure liquid-phase refrigerant to low-pressure two-phase gas-liquid refrigerant. The low-pressure two-phase gas-liquid refrigerant evaporates in the second flow path 121 of the heat exchanger 100 and becomes low-pressure gas-phase refrigerant. At this time, the refrigerant absorbs heat from water passing through the first flow path 111. The low-pressure gas-phase refrigerant passes through the four-way switching valve 12 through the second port P2 and the third port P3 in this order, and is then drawn into the compressor 11 through the suction port 11a.

[0058] (1-6-2-2) Water Circuit 20 The water circulation pump 21 draws water circulating through the water circuit 20 from the suction port 21a and discharges it from the discharge port 21b. A portion of the discharged water passes through the flow rate control valve 22 and reaches the first use heat exchanger 23. The water that has reached the first use heat exchanger 23 absorbs heat from the water stored in the water storage tank 31 in the first use heat exchanger 23. In other words, the water that has reached the first use heat exchanger 23 cools the water stored in the water storage tank 31. A portion of the remaining water discharged from the water circulation pump 21 reaches the second use heat exchanger 24. The water that has reached the second use heat exchanger 24 absorbs heat from the air in the space to be air-conditioned. In other words, the water that has reached the second use heat exchanger 24 cools the air in the space to be air-conditioned. The water that has absorbed heat in the first utilization heat exchanger 23 and the water that has absorbed heat in the second utilization heat exchanger 24 reach the first flow path 111 of the heat exchanger 100. The water that has reached the first flow path 111 of the heat exchanger 100 releases heat to the refrigerant passing through the second flow path 121. The water that has released heat is drawn into the water circulation pump 21 from the suction portion 21a.

[0059] (1-6-2-3) Water Supply Unit 30 Water stored in the water storage tank 31 is cooled by releasing heat to water passing through the first utilization heat exchanger 23. The water supply pump 32 draws in water cooled in the water storage tank 31 from the intake port 32a. The water drawn into the water supply pump 32 is discharged from the discharge port 32b to the mixing valve 33. The water discharged from the water supply pump 32 passes through the second port 33b and is mixed with water from the outside that has passed through the water intake unit 1a and reached the first port 33a. The water mixed in the mixing valve 33 passes through the third port 33c and is supplied to the outside of the refrigeration device 1 from the water supply unit 1b.

[0060] (1-6-3) Defrosting Operation Defrosting operation is an operation in which frost that has adhered to the surface of the heat source heat exchanger 13 during heating operation is melted and removed by the heat of the refrigerant condensing in the heat source heat exchanger 13. The operation of each part of the refrigeration device 1 during defrosting operation is the same as that during the cooling operation described above. Therefore, a detailed description of the defrosting operation will be omitted.

[0061] (2) Heat Exchanger 100 (2-1) Overall Configuration The heat exchanger 100 is a heat exchanger including a plurality of first inner fins 110, a plurality of second inner fins 120, a plurality of partition walls 130, a first spacing member 140, a second spacing member 150, a casing 160, a first circulation pipe 170a, a first circulation pipe 170b, a second circulation pipe 180a, and a second circulation pipe 180b. The heat exchanger 100 has a first flow path 111 through which water flows and a second flow path 121 through which a refrigerant flows formed therein.

[0062] The first inner fin 110, the second inner fin 120, and the partition wall 130 are metal plate-like members formed in the same rectangular shape. In this embodiment, as shown in Fig. 2, the first inner fin 110, the second inner fin 120, and the partition wall 130 have rectangular shapes that are long in the first direction.

[0063] The first inner fins 110 and the second inner fins 120 are stacked alternately with partition walls 130 sandwiched therebetween and housed in a casing 160. The number of each of the first inner fins 110 and the second inner fins 120 is not particularly limited and is set appropriately depending on the required performance.

[0064] In the following description, for convenience, the first direction may be referred to as the longitudinal direction DL. Also, the direction perpendicular to the first direction may be referred to as the width direction DW. Furthermore, the direction in which the first inner fins 110, the partition walls 130, and the second inner fins 120 are stacked may be referred to as the stacking direction DS. The longitudinal direction DL, the width direction DW, and the stacking direction DS correspond to the directions indicated by arrows in each drawing. The directions of back, front, left, and right used in the following description correspond to the directions indicated by arrows in each drawing.

[0065] (2-2) Detailed Configuration (2-2-1) First Inner Fin 110 The first inner fin 110 is a corrugated fin having a corrugated cross section. The corrugation of the first inner fin 110 is formed so that the peaks 110t of the corrugations extend along the longitudinal direction DL in a plan view. The first inner fin 110 forms a first flow path 111 together with adjacently stacked partition walls 130 and first spacing members 140 separating the partition walls 130. The first inner fin 110 is formed, for example, by using, but not limited to, press working.

[0066] It should be noted that the "waveform" of the first inner fin 110 is not limited to a shape in which semicircular projections and depressions are periodically arranged as shown in Fig. 6, but may be a periodically changing shape such as a sine wave, a rectangular wave, a triangular wave, etc. The same applies to the second inner fin 120.

[0067] (2-2-2) Second Inner Fin 120 The second inner fin 120 is a corrugated fin whose cross section is formed in a corrugated shape. The corrugation of the second inner fin 120 is formed so that the peaks 120t of the corrugations extend along the longitudinal direction DL in a plan view. The second inner fin 120 forms a second flow path 121 together with the adjacently stacked partition walls 130. The second inner fin 120 is formed, for example, by using a press working, although this is not a limitation.

[0068] (2-2-3) Partition Wall 130 The partition wall 130 is a flat plate that separates the first inner fin 110 and the second inner fin 120 in the stacking direction DS. The partition wall 130 separates the first flow passage 111 and the second flow passage 121 in the stacking direction DS.

[0069] (2-2-4) First Spacer 140 The first spacer 140 is disposed at the edge of the first flow path 111 and separates two adjacent partition walls 130 in the stacking direction DS. In other words, the first spacer 140 is a member that separates the two partition walls 130 so that the first inner fin 110 is disposed between the adjacent partition walls 130 in the stacking direction DS. The first spacer 140 is a strip-shaped member extending along the longitudinal direction DL. The first spacer 140 is disposed along both end edges of the partition walls 130 in the width direction DW. The height of the first spacer 140 in the stacking direction DS is formed to be the same as the height of the first inner fin 110 in the stacking direction DS. The first inner fin 110 is disposed between the first spacer members 140 disposed along both end edges of the partition walls 130 in the width direction DW.

[0070] The first spacing member 140 is formed using a material different from that of the second spacing member 150 so as to prevent leakage of the refrigerant flowing through the second flow path 121 when the water flowing through the first flow path 111 freezes and expands in volume. Specifically, the first spacing member 140 is formed using a material having a smaller Young's modulus than the material of the second spacing member 150. For example, the first spacing member 140 is made of copper or aluminum, whereas the second spacing member is made of SUS.

[0071] (2-2-5) Second spacing member 150 The second spacing member 150 is disposed at the edge of the second flow path 121 and separates two adjacent partition walls 130 in the stacking direction DS. In other words, the second spacing member 150 is a member that separates the two partition walls 130 so that the second inner fin 120 is disposed between the adjacent partition walls 130 in the stacking direction DS. The second spacing member 150 is a strip-shaped member extending along the longitudinal direction DL. The second spacing member 150 is disposed along both end edges of the partition walls 130 in the width direction DW. The height of the second spacing member 150 in the stacking direction DS is formed to be the same as the height of the second inner fin 120 in the stacking direction DS. The first inner fin 110 is disposed between the second spacing members 150 disposed along both end edges of the partition walls 130 in the width direction DW.

[0072] (2-2-6) Casing 160 The casing 160 is a substantially rectangular parallelepiped member that houses the first inner fin 110, the second inner fin 120, the partition wall 130, the first spacing member 140, and the second spacing member 150. The casing 160 has two main surfaces 160a that are perpendicular to the stacking direction DS, two first side surfaces 160b, and two second side surfaces 160c. The main surface 140a is a surface that is perpendicular to the stacking direction DS. The first side surface 160b is a surface that is perpendicular to the longitudinal direction DL. The second side surface 160c is a surface that is perpendicular to the width direction DW. The casing 160 has a first header 141, a second header 142, a third header 143, and a fourth header 144 formed therein.

[0073] The first header 141 is a space that divides the water that has flowed into the casing 160 into a plurality of first flow paths 111, or that merges the water that has passed through the first flow paths 111. The first header 141 is formed along the first side surface 160b on the near side.

[0074] The second header 142 is a space that divides the water that has flowed into the casing 160 into the multiple first flow paths 111, or that merges the water that has passed through the first flow paths 111. The second header 142 is formed along the first side surface 160b on the far side.

[0075] The third header 143 is a space that divides the refrigerant that has flowed into the casing 160 into multiple second flow paths 121, or that merges the refrigerant that has passed through the second flow paths 121. The third header 143 is formed along the first side surface 160b on the near side.

[0076] The fourth header 144 is a space that divides the refrigerant that has flowed into the casing 160 into multiple second flow paths 121, or that merges the refrigerant that has passed through the second flow paths 121. The fourth header 144 is formed along the first side surface 160b on the far side.

[0077] (2-2-7) First Circulation Pipe 170a and First Circulation Pipe 170b The first circulation pipe 170a is a pipe that circulates water through the first flow path 111. The first circulation pipe 170a is provided in the casing 160 so as to penetrate the first side surface 160b on the near side and communicate with the first header 141.

[0078] The first circulation pipe 170b is a pipe that circulates water through the first flow path 111. The first circulation pipe 170b is provided in the casing 160 so as to penetrate the first side surface 160b on the far side and to communicate with the second header 142.

[0079] (2-2-8) Second Circulation Pipe 180a and Second Circulation Pipe 180b The second circulation pipe 180a is a pipe that circulates the refrigerant through the second flow path 121. The second circulation pipe 180a is provided in the casing 160 so as to penetrate the second right side surface 160c and communicate with the third header 143.

[0080] The second flow pipe 180b is a pipe that circulates the refrigerant through the second flow path 121. The second flow pipe 180b is provided in the casing 160 so as to penetrate the second right side surface 160c and communicate with the fourth header 144.

[0081] (2-2-9) First Flow Passages 111 and Second Flow Passages 121 A plurality of first flow passages 111 arranged in the width direction DW are formed by accommodating the first inner fins 110 in a space surrounded by two partition walls 130 adjacent to each other in the stacking direction DS and two first spacing members 140 arranged between these partition walls 130. The first flow passages 111 are a space extending in the longitudinal direction DL surrounded by the first inner fins 110 and the partition walls 130, and a space extending in the longitudinal direction DL surrounded by the first inner fins 110, the partition walls 130, and the first spacing members 140.

[0082] The first inner fin 110, the partition wall 130, and the first spacing member 140 are bonded together by diffusion bonding. More specifically, the first inner fin 110 has a corrugated top 110t bonded to the partition wall 130 by diffusion bonding. The first spacing member 140 has a surface orthogonal to the stacking direction DS bonded to the partition wall 130 by diffusion bonding. Hereinafter, for convenience, the location where the partition wall 130 and the first spacing member 140 are bonded together will be referred to as a first bonding portion 140c.

[0083] A plurality of second flow paths 121 arranged in the width direction DW are formed by accommodating the second inner fins 120 in a space surrounded by two partition walls 130 adjacent to each other in the stacking direction DS and two second spacing members 150 arranged between these partition walls 130. The second flow paths 121 are a space extending in the longitudinal direction DL surrounded by the second inner fins 120 and the partition walls 130, and a space extending in the longitudinal direction DL surrounded by the second inner fins 120, the partition walls 130, and the second spacing members 150.

[0084] The second inner fin 120, the partition wall 130, and the second spacing member 150 are bonded together by diffusion bonding. More specifically, the corrugated peaks 120t of the second inner fin 120 are bonded to the partition wall 130 by diffusion bonding. The surfaces of the second spacing member 150 that are perpendicular to the stacking direction DS are bonded to the partition wall 130 by diffusion bonding. Hereinafter, for convenience, the location where the partition wall 130 and the second spacing member 150 are bonded together will be referred to as the second bonding portion 150c.

[0085] (2-3) Flow of Refrigerant and Water Water introduced from the first flow pipe 170a of the heat exchanger 100 passes through the first header 141 and flows into the first flow path 111. The water that flows into the first flow path 111 flows toward the rear side along the longitudinal direction DL in the first flow path 111. The water that reaches the rear side passes through the second header 142 and is discharged from the first flow pipe 170b. Furthermore, water introduced from the first flow pipe 170b of the heat exchanger 100 passes through the second header 142 and flows into the first flow path 111. The water that flows into the first flow path 111 flows toward the front side along the longitudinal direction DL in the first flow path 111. The water that reaches the front side passes through the first header 141 and is discharged from the first flow pipe 170a. In either case, the water flowing through the first flow passage 111 exchanges heat with the refrigerant in the adjacent second flow passage 121 via the partition wall 130 .

[0086] Meanwhile, the refrigerant introduced from the second flow pipe 180a of the heat exchanger 100 passes through the third header 143 and flows into the second flow path 121. The refrigerant that flows into the second flow path 121 flows through the second flow path 121 toward the rear side along the longitudinal direction DL. The refrigerant that reaches the rear side passes through the fourth header 144 and is discharged from the second flow pipe 180b. Furthermore, the refrigerant introduced from the second flow pipe 180b of the heat exchanger 100 passes through the fourth header 144 and flows into the second flow path 121. The refrigerant that flows into the second flow path 121 flows through the second flow path 121 toward the front side along the longitudinal direction DL. The refrigerant that reaches the front side passes through the third header 143 and is discharged from the second flow pipe 180a. In either case, the water flowing through the second flow path 121 exchanges heat with the water in the adjacent first flow path 111 via the partition wall 130 and condenses (during heating operation) or evaporates (during cooling operation and defrost operation).

[0087] (3) Features (3-1) The heat exchanger 100 is a heat exchanger that exchanges heat between water and a refrigerant, and includes a first flow path 111 through which water flows, a second flow path 121 through which a refrigerant flows, a partition wall 130, a first spacing member 140, and a second spacing member 150. The partition wall 130 separates the first flow path 111 from the second flow path 121. The first spacing member 140 is disposed on an edge of the first flow path 111 and separates two adjacent partition walls 130. The second spacing member 150 is disposed on an edge of the second flow path 121 and separates two adjacent partition walls 130. The first spacing member 140 is made of a different material and / or has a different shape from the second spacing member 150.

[0088] In refrigeration systems using plate-type heat exchangers, when refrigerant and water are used as fluids, the volume expansion of the frozen water can cause the separator to break, resulting in refrigerant leakage, or the partition separating the refrigerant flow path and the water flow path can break, causing the refrigerant to flow into the water flow path through the broken part and into the space to be air-conditioned.

[0089] In the heat exchanger 100, when the water flowing through the first flow path 111 freezes and expands in volume, the first spacing member 140 breaks before the second spacing member 150. Therefore, according to the heat exchanger 100, the breaking of the second spacing member 150 due to the freezing of the water flowing through the first flow path 111 is suppressed, and therefore the refrigerant flowing through the second flow path 121 is suppressed from leaking to the outside of the heat exchanger 100.

[0090] (3-2) The material of the first spacing member 140 has a smaller Young's modulus than the material of the second spacing member 150 .

[0091] When water flowing through the first flow path 111 freezes and expands in volume, the first spacing member 140, which is made of a material with a smaller Young's modulus than the second spacing member 150, breaks before the second spacing member 150. Therefore, according to the heat exchanger 100, the breakage of the second spacing member 150 due to the freezing of water flowing through the first flow path 111 is suppressed, and therefore the refrigerant flowing through the second flow path 121 is suppressed from leaking to the outside of the heat exchanger 100.

[0092] (3-3) The first spacing member 140 is made of copper or aluminum, and the second spacing member 150 is made of stainless steel.

[0093] (3-4) The first spacing member 140 and the second spacing member 150 are bonded to the partition wall 130 using diffusion bonding.

[0094] (3-5) The refrigeration device 1 includes a heat exchanger 100 .

[0095] (4) Modifications (4-1) Modification A First spacing member 140 may be formed in a shape different from that of second spacing member 150 so as to prevent leakage of refrigerant flowing through second flow path 121 when water flowing through first flow path 111 freezes and expands in volume. Specifically, first spacing member 140 may have a recess 140d formed on its outer surface that is recessed toward first flow path 111. Figure 7 is a cross-sectional view of heat exchanger 100 according to modification A.

[0096] When water flowing through first flow path 111 freezes and expands in volume, stress concentrates in recess 140d, causing first spacing member 140 to break before second spacing member 150. Therefore, with heat exchanger 100 according to modification A, breaking of second spacing member 150 due to freezing of water flowing through first flow path 111 is suppressed, and therefore leakage of refrigerant flowing through second flow path 121 to the outside of heat exchanger 100 is suppressed.

[0097] In the heat exchanger 100 according to variant A, the first spacing member 140 may be formed using a different material from the second spacing member 150, as in the above-described embodiment, or may be formed using the same material as the second spacing member 150.

[0098] (4-2) Modification B The shape of the first spacing member 140 is not limited to that of Modification A, as long as leakage of the refrigerant flowing through the second flow path 121 is suppressed when water flowing through the first flow path 111 freezes and expands in volume. Specifically, the first spacing member 140 may be formed so that the width d1 of the first joint portion 140c in the width direction DW is narrower than the width d2 of the second joint portion 150c in the width direction DW. Figure 8 is a cross-sectional view of the heat exchanger 100 according to Modification B.

[0099] Because the width d1 is narrower than the width d2, when the same pressure is generated in the first flow path 111 and the second flow path 121, a greater stress acts on the first joint portion 140c than on the second joint portion 150c. Therefore, when water flowing through the first flow path 111 freezes and expands in volume, the first joint portion 140c breaks before the second joint portion 150c breaks. Therefore, with the heat exchanger 100 according to Modification B, the breakage of the second spacing member 150 due to the freezing of water flowing through the first flow path 111 is suppressed, and therefore the refrigerant flowing through the second flow path 121 is suppressed from leaking to the outside of the heat exchanger 100.

[0100] As shown in FIG. 8 , the joint portion (second joint portion 150c) of the second spacing member 150 with the partition wall 130 may have a portion that overlaps with the first flow path 111 when viewed from the stacking direction DS (region 150d shown by a dotted line in FIG. 8 ). In this case, the width d1 of the first spacing member 140 when viewed from the stacking direction DS may be equal to or less than half the width d2 of the second spacing member 150. Furthermore, in the second spacing member 150, the width d2a (same as d2-d1 in this embodiment) in the width direction DW of the region 150d that overlaps with the first flow path 111 may be equal to or greater than the width d2b (same as d1 in this embodiment) of the portion that does not overlap with the first flow path 111 in the stacking direction DS.

[0101] In the heat exchanger 100 according to variant B, the first spacing member 140 may be formed using a different material from the second spacing member 150, as in the above-described embodiment, or may be formed using the same material as the second spacing member 150.

[0102] (4-3) Modification C In the above embodiment, the refrigerant used is propane. However, the refrigerant used is not limited to this, and well-known refrigerants such as HC, HFC (R410A, R32, etc.), HFO, and natural refrigerant can be used.

[0103] Even when a flammable or toxic refrigerant is used, the heat exchanger 100 can prevent refrigerant leakage due to rupture of the members or joints that form the second flow path 121. Note that a flammable refrigerant refers to a refrigerant classified as 2 L or more in the U.S. ANSI / ASHRAE 34 standard.

[0104] (4-4) Modification D In the above-described embodiment, the first inner fins 110 and the second inner fins 120 are stacked so that both the first flow paths 111 and the second flow paths 121 are aligned in the width direction DW, but the arrangement of the first inner fins 110 and the second inner fins 120 is not limited to this. For example, the first inner fins 110 and the second inner fins 120 may be stacked so that one of the first flow paths 111 and the second flow paths 121 is aligned in the width direction DW and the other of the first flow paths 111 and the second flow paths 121 is aligned in the longitudinal direction DL.

[0105] Although the embodiments of the present disclosure have been described above, it will be understood that various changes in form and details can be made without departing from the spirit and scope of the present disclosure as defined in the claims.

[0106] 1: Refrigeration device 100: Heat exchanger 111: First flow path 121: Second flow path 130: Partition wall 140: First spacing member 140d: Recess 150: Second spacing member DS: Stacking direction

[0107] Japanese Patent Application Publication No. 10-132476

Claims

1. A heat exchanger (100) for exchanging heat between water and a refrigerant, comprising: a first flow path (111) through which the water flows; a second flow path (121) through which the refrigerant flows; a partition wall (130) separating the first flow path (111) and the second flow path (121); a first spacing member (140) disposed on an edge of the first flow path (111) to separate two adjacent partition walls (130); and a second spacing member (150) disposed on an edge of the second flow path (121) to separate two adjacent partition walls (130), wherein the first spacing member (140) is made of a different material from the second spacing member (150) and / or has a different shape from the second spacing member (150).

2. The heat exchanger (100) according to claim 1, wherein the material of the first spacing member (140) has a Young's modulus smaller than that of the material of the second spacing member (150).

3. The heat exchanger (100) according to claim 2, wherein the first spacing member (140) is made of copper or aluminum, and the second spacing member (150) is made of stainless steel.

4. The heat exchanger (100) according to claim 1, wherein the first spacer member (140) has a recess (140d) formed on its outer surface that is recessed toward the first flow path (111).

5. The heat exchanger (100) according to claim 1, wherein the width (d1) of the first spacing member (140) is narrower than the width (d2) of the second spacing member (150).

6. The heat exchanger (100) according to claim 5, wherein a joint (150c) between the second spacing member (150) and the partition wall (130) has a portion (150d) that overlaps with the first flow path (111) when viewed from the stacking direction (DS).

7. The heat exchanger (100) according to claim 6, wherein the width (d1) of the first spacing member (140) is equal to or less than half the width (d2) of the second spacing member (150).

8. The heat exchanger (100) of claim 1, wherein the first spacer (140) and the second spacer (150) are bonded to the partition wall (130) using diffusion bonding.

9. The heat exchanger (100) according to any one of claims 1 to 8, wherein the refrigerant is flammable or toxic.

10. A refrigeration device (1) comprising a heat exchanger (100) according to any one of claims 1 to 9.

Images