CN107208943B

CN107208943B - Refrigerant evaporator

Info

Publication number: CN107208943B
Application number: CN201680006394.9A
Authority: CN
Inventors: 森本正和; 鸟越荣一; 石坂直久
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 2015-02-27
Filing date: 2016-02-25
Publication date: 2020-08-14
Anticipated expiration: 2036-02-25
Also published as: JP6558268B2; DE112016000954T5; US20170328615A1; JP2016164486A; CN107208943A; WO2016136266A1

Abstract

A refrigerant evaporator (1) that exchanges heat between a fluid to be cooled and a refrigerant, comprising: a first heat exchange unit (12) through which the refrigerant flows and which exchanges heat between the fluid to be cooled and the refrigerant; a second heat exchange part (22) through which the refrigerant flows, which is arranged opposite to the first heat exchange part and exchanges heat between the fluid to be cooled and the refrigerant; a first tank (13) disposed below the first heat exchange unit and distributing the refrigerant to the first heat exchange unit; a second tank (23) disposed below the second heat exchange unit and collecting the refrigerant flowing through the second heat exchange unit; and a third tank (30) which is joined to the first tank and the second tank and guides the refrigerant collected in the second tank to the first tank. A gap is formed between the first tank, the second tank, and the third tank. At least one of the joint portions (133, 304) of the first tank and the third tank and the joint portions (233, 305) of the second tank and the third tank is provided with a drainage channel (40, 50) for discharging water accumulated in the gap.

Description

Refrigerant evaporator

Cross reference to related applications

The present application is based on Japanese patent application 2015-38169, filed on 27/2/2015, and Japanese patent application 2016-32052, filed on 23/2/2016, the disclosures of which are incorporated herein by reference.

Technical Field

The present invention relates to a refrigerant evaporator that performs heat exchange between a fluid to be cooled and a refrigerant.

Background

As such a refrigerant evaporator, there is a refrigerant evaporator described in patent document 1. The refrigerant evaporator described in patent document 1 includes a first heat exchange unit and a second heat exchange unit that exchange heat with air as a cooling target fluid. The first heat exchange portion and the second heat exchange portion are arranged to be opposed to each other in the air flow direction. The first heat exchange portion is divided into a first core and a second core in a direction orthogonal to a flow direction of air. The second heat exchange portion is also divided into the first core and the second core in a direction orthogonal to the flow direction of the air. The first core of the first heat exchange portion is opposite to the first core of the second heat exchange portion in a flow direction of the air. The second core of the first heat exchange portion is opposite to the second core of the second heat exchange portion in a flow direction of the air. The refrigerant evaporator described in patent document 1 includes a pair of tanks provided at both ends of the first heat exchange portion in the vertical direction and a pair of tanks provided at both ends of the second heat exchange portion in the vertical direction. The refrigerant evaporator described in patent document 1 includes a replacement tank between a tank provided below the first heat exchange unit in the vertical direction and a tank provided below the second heat exchange unit in the vertical direction.

In the refrigerant evaporator described in patent document 1, the refrigerant flows from the tank on the vertically upper side of the second heat exchange portion to the first core portion and the second core portion of the second heat exchange portion. The refrigerant flowing into the first core of the second heat exchange portion flows from the tank on the vertically lower side of the second heat exchange portion to the second core of the first heat exchange portion through the replacement tank and the tank on the vertically lower side of the first heat exchange portion. The refrigerant flowing into the second core of the second heat exchange portion flows from the tank on the vertically lower side of the second heat exchange portion to the first core of the first heat exchange portion via the replacement tank and the tank on the vertically lower side of the first heat exchange portion. The refrigerant flowing into the first core portion of the first heat exchange portion and the refrigerant flowing into the second core portion of the first heat exchange portion are discharged via the tank vertically above the second heat exchange portion.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2013-185723

However, in the refrigerant evaporator described in patent document 1, when condensed water is generated on the outer surfaces of the first heat exchange portion and the second heat exchange portion by heat exchange between the refrigerant and the air, the condensed water flows vertically downward. If a gap is formed between the tank on the vertically lower side of the first heat exchange unit, the tank on the vertically lower side of the second heat exchange unit, and the replacement tank, there is a possibility that condensed water may accumulate in the gap. When the stored water freezes, the tanks may be damaged by the volume expansion of the water, so-called frost cracking.

Disclosure of Invention

The invention aims to provide a refrigerant evaporator capable of inhibiting frost cracking.

In one aspect of the present invention, a refrigerant evaporator that exchanges heat between a fluid to be cooled and a refrigerant includes: a first heat exchange unit in which a refrigerant flows and which exchanges heat between a fluid to be cooled and the refrigerant; a second heat exchange portion that is disposed opposite to the first heat exchange portion, and through which the refrigerant flows, the second heat exchange portion performing heat exchange between the fluid to be cooled and the refrigerant; a first tank disposed below the first heat exchange unit and distributing the refrigerant to the first heat exchange unit; a second tank disposed below the second heat exchange unit and collecting the refrigerant flowing through the second heat exchange unit; and a third tank that is joined to the first tank and the second tank and guides the refrigerant collected to the second tank to the first tank. A gap is formed between the first tank, the second tank, and the third tank. Drainage channels are formed in both the joint portion between the first tank and the third tank and the joint portion between the second tank and the third tank, and the drainage channels drain water accumulated in the gaps.

In one aspect of the present invention, a refrigerant evaporator that exchanges heat between a fluid to be cooled and a refrigerant includes: a first heat exchange unit in which a refrigerant flows and which exchanges heat between a fluid to be cooled and the refrigerant; a second heat exchange portion that is disposed opposite to the first heat exchange portion, and through which the refrigerant flows, the second heat exchange portion performing heat exchange between the fluid to be cooled and the refrigerant; a first tank disposed below the first heat exchange unit and distributing the refrigerant to the first heat exchange unit; a second tank disposed below the second heat exchange unit and collecting the refrigerant flowing through the second heat exchange unit; a connecting portion that connects the first tank and the second tank; and a third tank that is joined to the first tank and the second tank and guides the refrigerant collected to the second tank to the first tank. At least one opening is formed in the connecting portion. A drain passage is formed in both the joint portion between the first tank and the third tank and the joint portion between the second tank and the third tank, and the drain passage is located below the opening formed in the joint portion and discharges water passing through the opening.

According to these configurations, when the condensate water generated on the outer surfaces of the first heat exchange portion and the second heat exchange portion flows into the gap between the first tank and the third tank, the condensate water is discharged to the outside through the drain passage. Therefore, the condensed water is less likely to accumulate in the gap between the first to third tanks, and therefore, frost cracking due to freezing of the condensed water can be suppressed.

Drawings

Fig. 1 is a perspective view showing a schematic configuration of a refrigerant evaporator according to a first embodiment.

Fig. 2 is a perspective view showing an exploded perspective structure of the refrigerant evaporator according to the first embodiment.

Fig. 3 is a perspective view showing an exploded perspective structure of an upwind-side distribution tank, a downwind-side collection tank, and a replacement tank of the refrigerant evaporator according to the first embodiment.

Fig. 4 is a perspective view schematically showing the flow of the refrigerant in the refrigerant evaporator of the first embodiment.

Fig. 5 is a side view showing the structure of a drain passage of the refrigerant evaporator of the first embodiment.

Fig. 6 is a side view showing the structure of a drain passage of a first modification of the refrigerant evaporator of the first embodiment.

Fig. 7 is a side view showing a configuration of a drain passage of a second modification of the refrigerant evaporator of the first embodiment.

Fig. 8 is a side view showing a configuration of a drain passage of a second modification of the refrigerant evaporator of the first embodiment.

Fig. 9 is a side view showing the structure of a drain passage of a third modification of the refrigerant evaporator of the first embodiment.

Fig. 10 is a side view showing a configuration of a drain passage of a fourth modification of the refrigerant evaporator according to the first embodiment.

Fig. 11 is a cross-sectional view showing cross-sectional configurations of an upwind distribution tank, a downwind collection tank, and a replacement tank of a refrigerant evaporator according to a second embodiment.

Detailed Description

< first embodiment >

A first embodiment of the refrigerant evaporator will be described below. The refrigerant evaporator 1 of the present embodiment shown in fig. 1 is used in a refrigeration cycle of a vehicle air conditioner for adjusting the temperature in a vehicle interior. Specifically, the refrigerant evaporator 1 is a cooling heat exchanger that cools air by absorbing heat from air blown into a vehicle interior and evaporating a liquid-phase refrigerant. As is well known, the refrigeration cycle includes a compressor, a radiator, an expansion valve, and the like, which are not shown, in addition to the refrigerant evaporator 1.

As shown in fig. 1 and 2, the refrigerant evaporator 1 includes two

evaporation units

10 and 20 and a replacement tank 30. The

evaporation portions

10 and 20 are disposed on the upstream side and the downstream side with respect to the air flow direction X. In the present embodiment, the air flow direction X is a direction orthogonal to the vertical directions Y1 and Y2. Hereinafter, the evaporation unit 10 disposed on the upstream side in the air flow direction X is referred to as "windward evaporation unit 10". The evaporation unit 20 disposed on the downstream side in the air flow direction X is referred to as a "leeward evaporation unit 20".

The windward evaporation unit 10 includes a windward collection tank 11, a windward heat exchange unit 12, and a windward distribution tank 13. The windward collection tank 11, the windward heat exchange unit 12, and the windward distribution tank 13 are arranged in this order in the vertical direction lower Y1.

The upper air side heat exchange unit 12 is formed in a rectangular parallelepiped shape. The upper air side heat exchange portion 12 is disposed so that the air flow direction X is the thickness direction. An upwind-side distributor box 13 is attached to an end surface 12d on the Y1 side vertically below the upwind-side heat exchange unit 12. An upwind collection box 11 is attached to an end surface 12e of the upwind side heat exchange unit 12 on the Y2 side in the vertical direction. The upper air side heat exchange portion 12 has a structure in which a plurality of tubes 12a and a plurality of fins 12b are alternately stacked in the horizontal direction. In fig. 2, the tubes 12a and the fins 12b are not shown. The tube 12a has a flat cross section, and the tube 12a is disposed so as to extend in the vertical directions Y1 and Y2. Inside the tube 12a, a flow path through which the refrigerant flows is formed. The fin 12b includes a so-called corrugated fin formed by bending a thin metal plate. The fins 12b are disposed between the adjacent tubes 12a in the horizontal direction, and are joined to the outer surfaces of the tubes 12 a. As shown in fig. 2, the windward side heat exchange portion 12 is divided into a first windward core portion 121 and a second windward core portion 122 in the stacking direction of the tubes 12a and the fins 12 b. As shown in fig. 1, the upper air side heat exchange portion 12 has side plates 12c at both ends in the stacking direction of the tubes 12a and the fins 12 b. The side plate 12c is a member for reinforcing the upper air side heat exchange portion 12.

The windward distribution box 13 includes a cylindrical member having a flow path for the refrigerant inside. Both ends of the windward distribution box 13 in the axial direction are closed. As shown in fig. 2, the windward distribution box 13 has a partition plate 13a at the center in the axial direction. The partition plate 13a divides the internal flow path of the windward distribution box 13 into a first distribution portion 131 and a second distribution portion 132. Further, a plurality of through holes, not shown, into which the end portions of the pipes 12a on the side of Y1 in the vertical direction are inserted are formed in the outer peripheral surface of the windward distribution box 13. Through the through holes, the internal flow paths of the first distribution portion 131 communicate with the tubes 12a of the first windward core portion 121, and the internal flow paths of the second distribution portion 132 communicate with the tubes 12a of the second windward core portion 122. That is, the first distribution portion 131 distributes the refrigerant to the tubes 12a of the first windward core portion 121. The second distribution portion 132 distributes the refrigerant to the tubes 12a of the second windward core portion 122.

As shown in fig. 3, a planar joint 133 is formed on the outer peripheral surface of the upstream distribution box 13 so as to extend in the axial direction. The engaging portion 133 is a portion that engages with the replacement tank 30. The joint 133 is formed with a through hole 134 penetrating the internal flow path of the first distribution portion 131. The through-holes 134 constitute a flow path for guiding the refrigerant in the replacement tank 30 to the first distribution portion 131. The joint 133 is formed with a through hole 135 that penetrates the internal flow path of the second distribution portion 132. The through-holes 135 constitute a flow path for guiding the refrigerant in the replacement tank 30 to the second distribution portion 132.

As shown in fig. 1 and 2, the windward collection tank 11 includes a cylindrical member having a flow path for the refrigerant inside. One end portion in the axial direction of the windward collection box 11 is closed. A refrigerant discharge port 11a is formed at the other end portion in the axial direction of the windward collection tank 11. The refrigerant discharge port 11a is connected to a suction side of a compressor, not shown. Further, a plurality of through holes, not shown, into which the end portions of the tubes 12a on the vertical upper Y2 side are inserted are formed in the outer peripheral surface of the windward collection box 11. Through the through holes, the internal flow path of the windward collection tank 11 communicates with the tubes 12a of the first windward core section 121 and the tubes 12a of the second windward core section 122, respectively. That is, the refrigerant flowing through the tubes 12a of the first windward core portion 121 and the refrigerant flowing through the tubes 12a of the second windward core portion 122 are collected in the windward collection tank 11. The refrigerant collected in the windward collection tank 11 is guided to the compressor through the refrigerant discharge port 11 a.

The leeward evaporation unit 20 includes a leeward distribution box 21, a leeward heat exchange unit 22, and a leeward collection box 23. The leeward distribution box 21, the leeward heat exchange unit 22, and the leeward collection box 23 are arranged in this order in the order of the vertical lower direction Y1.

The leeward heat exchange portion 22 has substantially the same configuration as the windward heat exchange portion 12. That is, the leeward heat exchange portion 22 is formed in a rectangular parallelepiped shape and is disposed so that the air flow direction X is the thickness direction. The leeward heat exchange portion 22 includes a structure in which a plurality of tubes 22a and a plurality of fins 22b are alternately stacked in the horizontal direction, and side plates 22c are provided at both ends of the tubes 22a and the fins 22b in the stacking direction. A leeward collection tank 23 is attached to an end surface 22d of the leeward heat exchange unit 22 on the vertically lower Y1 side. A leeward distribution box 21 is attached to an end surface 22e of the leeward side heat exchange portion 22 on the Y2 side in the vertical direction. As shown in fig. 2, the leeward heat exchange portion 22 is divided into a first leeward core portion 221 and a second leeward core portion 222, and the first leeward core portion 221 is opposed to the first windward core portion 121 and the second leeward core portion 222 is opposed to the second windward core portion 122 in the air flow direction X.

The leeward distribution box 21 includes a cylindrical member having a flow path for the refrigerant inside. One end portion in the axial direction of the leeward distribution box 21 is closed. A refrigerant inlet port 21a is formed at the other end portion in the axial direction of the leeward distribution box 21. The low-pressure refrigerant decompressed by an expansion valve, not shown, flows into the refrigerant inlet 21 a. Further, a plurality of through holes, not shown, into which the end portions of the tubes 22a on the vertical upper Y2 side are inserted are formed in the outer peripheral surface of the leeward distribution box 21. Through the through holes, the internal flow path of the leeward distribution box 21 communicates with the tubes 22a of the first leeward core portion 221 and the tubes 22a of the second leeward core portion 222. That is, the refrigerant flowing into the leeward distribution box 21 from the refrigerant inlet 21a is distributed to the tubes 22a of the first leeward core portion 221 and the tubes 22a of the second leeward core portion 222.

The leeward collection tank 23 includes a cylindrical member having a flow path for the refrigerant inside. Both ends in the axial direction of the leeward collecting box 23 are closed. The leeward collection tank 23 has a partition plate 23a at the center in the axial direction. As shown in fig. 2, the partition 23a divides the internal flow path of the leeward collection tank 23 into a first collection portion 231 and a second collection portion 232. Further, a plurality of through holes, not shown, into which the end portions of the tubes 22a on the side of the Y1 in the vertical direction are inserted are formed in the outer peripheral surface of the leeward collection box 23. Through the through holes, the internal flow channels of the first collecting portion 231 communicate with the tubes 22a of the first leeward core portion 221, and the internal flow channels of the second collecting portion 232 communicate with the tubes 22a of the second leeward core portion 222. That is, the refrigerant flowing through the tubes 22a of the first leeward core portion 221 is collected in the first collection portion 231. The refrigerant flowing through the tubes 22a of the second leeward core portion 222 is collected in the second collecting portion 232.

As shown in fig. 3, a planar joint 233 is formed on the outer peripheral surface of the leeward collection box 23 so as to extend in the axial direction. The engaging portion 233 is a portion that engages with the replacement tank 30. The joint 233 has a through hole 234 penetrating the internal flow path of the first collecting portion 231. The through-hole 234 is formed as a flow path for guiding the refrigerant in the first collecting portion 231 to the replacement tank 30. The joint 233 is formed with a through hole 235 penetrating into the internal flow path of the second collecting portion 232. Through-hole 235 is formed as a flow path for guiding the refrigerant in second collecting portion 232 to replacement tank 30.

In the present embodiment, the windward collection tank 13 corresponds to a first tank, and the leeward heat exchange unit 23 corresponds to a second tank. The windward heat exchange unit 12 corresponds to a first heat exchange unit, and the leeward heat exchange unit 22 corresponds to a second heat exchange unit.

The replacement box 30 is provided between the windward distribution box 13 and the leeward collection box 23. In the present embodiment, the replacement tank 30 corresponds to a third tank. The replacement tank 30 includes a cylindrical member having a flow path for the refrigerant inside. A partition member 301 is provided inside the replacement tank 30. Partition member 301 divides the internal space of replacement tank 30 into first refrigerant flow path 302 and second refrigerant flow path 303.

As shown in fig. 3, a planar joint portion 304 that is joined to the joint portion 133 of the upstream distribution box 13 and a planar joint portion 305 that is joined to the joint portion 233 of the downstream collection box 23 are formed on the outer peripheral surface of the replacement box 30.

A through hole 306 penetrating through the first refrigerant flow path 302 is formed in the joint portion 304. The through-holes 306 are arranged so as to be continuous with the through-holes 134 of the windward distribution box 13. A through hole 307 penetrating the first refrigerant flow path 302 is formed in the joint portion 305. The through hole 307 is arranged to be continuous with the through hole 235 of the leeward collecting tank 23. That is, the refrigerant collected in the second collecting portion 232 of the leeward collecting tank 23 flows into the first refrigerant flow path 302 through the through hole 235 of the leeward collecting tank 23 and the through hole 307 of the replacement tank 30. The refrigerant flowing into the first refrigerant flow path 302 is guided to the first distributing portion 131 of the windward distributing box 13 via the through hole 306 of the replacement box 30 and the through hole 134 of the windward distributing box 13.

A through hole 308 penetrating into the second refrigerant flow channel 303 is formed in the joint portion 304. The through-holes 308 are disposed so as to be continuous with the through-holes 135 of the windward distribution box 13. A through hole 309 penetrating into the second refrigerant flow path 303 is formed in the joint portion 305. The through-hole 309 is disposed so as to be continuous with the through-hole 234 of the leeward collection tank 23. That is, the refrigerant collected in the first collecting portion 231 of the leeward collecting tank 23 flows into the second refrigerant flow path 303 through the through hole 234 of the leeward collecting tank 23 and the through hole 309 of the replacement tank 30. The refrigerant flowing into the second refrigerant flow path 303 is guided to the second distribution portion 132 of the upstream side distribution box 13 via the through holes 308 of the replacement box 30 and the through holes 135 of the upstream side distribution box 13.

In this way, the replacement tank 30 functions as a portion for guiding the refrigerant collected in the leeward collection tank 23 to the windward distribution tank 13. The replacement tank 30 functions as a portion for replacing the refrigerant flow in the leeward heat exchange portion 22 and the refrigerant flow in the windward heat exchange portion 12 in the stacking direction of the

tubes

12a and 22 a.

Next, a method of cooling the refrigerant flow and the air in the refrigerant evaporator 1 will be described.

As indicated by an arrow a in fig. 4, the refrigerant decompressed by the expansion valve, not shown, is introduced into the interior of the leeward distribution box 21 from the refrigerant inlet 21 a. As indicated by arrow B, C, the refrigerant is distributed in the leeward distribution tank 21 and flows into the first and second

leeward core portions

221, 222 of the leeward distribution tank 21.

The refrigerant flowing into the first leeward core portion 221 and the second leeward core portion 222 passes through the inside of each tube 22a and flows toward the vertical lower direction Y1. At this time, the refrigerant flowing through the inside of the tube 22a exchanges heat with air flowing through the outside of the tube 22a in the X direction. In this way, the air is cooled by absorbing heat from the air by evaporation of a part of the refrigerant.

As indicated by arrow D, the refrigerant flowing through the tubes 22a of the first leeward core portion 221 is collected in the first collection portion 231 of the leeward collection tank 23. As indicated by arrow F, the refrigerant collected in the first collecting portion 231 flows into the second distribution portion 132 of the windward distribution tank 13 through the second refrigerant flow path 303 of the replacement tank 30. The refrigerant flowing into the second distribution portion 132 flows into the second windward core portion 122 as indicated by an arrow H.

As indicated by arrow E, the refrigerant flowing through the tubes 22a of the second leeward core portion 222 is collected to the second collection portion 232 of the leeward collection tank 23. As indicated by arrow G, the refrigerant collected in the second collecting portion 232 flows into the first distributing portion 131 of the upstream distribution tank 13 through the first refrigerant flow path 302 of the replacement tank 30. The refrigerant flowing into the first distribution portion 131 flows into the first windward core portion 121 as indicated by the arrow I.

The refrigerant flowing into the first and second

windward core portions

121 and 122 flows through the insides of the respective tubes 22a toward the vertical direction upper direction Y2. At this time, the refrigerant flowing through the inside of the tube 22a exchanges heat with air flowing through the outside of the tube 22a in the X direction. In this way, the air is cooled by absorbing heat from the air by evaporation of a part of the refrigerant.

As indicated by an arrow K, J, the refrigerant flowing through the first windward core portion 121 and the second windward core portion 122 is collected in the windward collection tank 11. As indicated by arrow L, the refrigerant collected in the windward collection tank 11 is supplied from the refrigerant discharge port 11a of the windward collection tank 11 to the suction side of the compressor, not shown.

However, when condensed water is generated on the outer surfaces of the upper-wind side heat exchange portion 12 and the lower-wind side heat exchange portion 22 by heat exchange between the refrigerant and the air, the condensed water flows vertically downward Y1. As shown in fig. 5, the condensate may be accumulated in a clearance CL1 between the upstream-side distributor tank 13, the downstream-side collection tank 23, and the replacement tank 30. When the condensed water stored in the clearance CL1 freezes as the temperature decreases, the

tanks

13, 23, and 30 may be damaged by the volume expansion of the water, so-called frost cracking.

Therefore, the refrigerant evaporator 1 of the present embodiment is provided with a drain structure for discharging the condensed water accumulated in the clearance CL 1. Next, a specific case of the drainage structure will be described.

As shown in fig. 3, a plurality of drain grooves 310 are formed in the joint portion 304 of the replacement tank 30 along the inclined surface of the joint portion 304. Further, at the joint 133 of the windward distribution box 13, a drain groove 136 is formed at a position corresponding to the drain groove 310 of the joint 304 of the replacement box 30. As shown in fig. 5, the straight drainage passage 40 is formed by a space surrounded by the drainage groove 310 formed in the joint portion 304 of the replacement tank 30 and the drainage groove 136 formed in the joint portion 133 of the windward distribution tank 13. An inflow port 41 that opens to the clearance CL1 is formed at one end of the drain passage 40. A discharge port 42 that opens into a space on the vertical lower Y1 side of the windward side distributor box 13 is formed at the other end portion of the drain passage 40. The discharge port 42 is disposed vertically below the clearance CL1 on the Y1 side.

As shown in fig. 3, a plurality of drain grooves 311 are formed along the inclined surface of the joint 305 in the joint 305 of the replacement tank 30. In joint 233 of leeward collection tank 23, drain groove 236 is formed at a position corresponding to drain groove 311 of joint 305 of replacement tank 30. As shown in fig. 5, the straight drainage passage 50 is formed by a space surrounded by the drainage groove 311 formed in the joint 305 of the replacement tank 30 and the drainage groove 236 formed in the joint 233 of the leeward collection tank 23. An inflow port 51 opening to the clearance CL1 is formed at one end of the drain passage 50. A discharge port 52 that opens into a space on the vertically lower Y1 side of the leeward collection tank 23 is formed at the other end portion of the drain passage 50. The discharge port 52 is disposed vertically below the clearance CL1 on the Y1 side.

In fig. 2 and 4, the

drain grooves

310 and 311 of the replacement tank 30, the drain groove 136 of the windward distribution tank 13, and the drain groove 236 of the leeward collection tank 23 are not shown.

According to the refrigerant evaporator 1 of the present embodiment described above, the following operations and effects (1) and (2) can be obtained.

(1) As indicated by arrows W1 and W2 in fig. 5, the condensed water accumulated in the clearance CL1 is discharged to the outside through the drain passage 40 or the drain passage 50. Therefore, it becomes difficult to accumulate the condensed water in the clearance CL1, and therefore, it is possible to suppress frost cracking caused by freezing of the condensed water.

(2) The discharge port 42 of the drain passage 40 and the discharge port 52 of the drain passage 50 are disposed vertically below the clearance CL1 on the Y1 side. This makes it easier to discharge the condensed water accumulated in the clearance CL1, and therefore, frost cracking can be more reliably suppressed.

(first modification)

Next, a first modification of the refrigerant evaporator 1 of the first embodiment will be described.

As shown in fig. 6, in the refrigerant evaporator 1 of the present modification, the cross-sectional area of the discharge port 42 of the drain passage 40 is larger than the cross-sectional area of the inflow port 41 of the drain passage 40. Similarly, the cross-sectional area of the discharge port 52 of the drain 50 is larger than the cross-sectional area of the inflow port 51 of the drain 50. With this configuration, the condensed water accumulated in the clearance CL1 is more easily discharged, and therefore frost cracking can be more effectively suppressed. Further, the same operation and effect can be obtained as long as the sectional area of the discharge port 42 is equal to or larger than the sectional area of the inflow port 41. Further, the same operation and effect can be obtained if the sectional area of the outlet 52 is equal to or larger than the sectional area of the inlet 51.

(second modification)

Next, a second modification of the refrigerant evaporator 1 of the first embodiment will be described.

As shown in fig. 7, the

drainage passages

40 and 50 may be formed only by the

drainage grooves

310 and 311 formed in the replacement tank 30. As shown in fig. 8, the drain passage 40 may be formed only by the drain groove 136 formed in the windward distribution box 13. Further, the drain passage 50 may be constituted only by the drain groove 236 formed in the leeward collection tank 23. In short, at least one of the

joints

133 and 304 between the windward distribution tank 13 and the replacement tank 30 and the

joints

233 and 305 between the leeward collection tank 23 and the replacement tank 30 shown in fig. 2 may be provided with a drain passage for discharging the water accumulated in the clearance CL 1.

(third modification)

Next, a third modification of the refrigerant evaporator 1 of the first embodiment will be described.

As shown in fig. 9, the

drainage channels

40 and 50 may be formed in an arc shape. The shape of the

drainage passages

40 and 50 is not limited to the shape shown in fig. 5 to 9, and may be appropriately changed.

(fourth modification)

Next, a fourth modification of the refrigerant evaporator 1 of the first embodiment will be described.

As shown in fig. 10, in the refrigerant evaporator 1 of the present modification, the cross-sectional area of the gap between the upstream distribution tank 13 and the downstream collection tank 23 at the closest point is set to "Sa". The cross-sectional area of the inlet 41 of the drain passage 40 is set to "Sb 1", and the cross-sectional area of the outlet 42 of the drain passage 40 is set to "Sc 1". Further, the sectional area of the inflow port 51 of the drain passage 50 is set to "Sb 2", and the sectional area of the discharge port 52 of the drain passage 50 is set to "Sc 2".

These cross-sectional areas Sa, Sb1, Sb2, Sc1, and Sc2 are set so as to satisfy the following relational expressions f1 and f 2.

Sa<Sb1≤Sc1 (f1)

Sa<Sb2≤Sc2 (f2)

With this configuration, the condensed water flowing into the clearance CL1 from the portion where the windward distribution tank 13 and the leeward collection tank 23 are closest to each other is more easily discharged, and therefore, frost cracking can be effectively suppressed.

In the case where the refrigerant evaporator 1 is disposed in an inclined posture, the same operation and effect can be obtained as long as the drainage passage disposed on the vertically lower side of the drainage passage 40 and the drainage passage 50 satisfies the above expression. The inclined posture indicates that the longitudinal direction of the

pipes

12a and 22a intersects the vertical direction.

< second embodiment >

Next, a second embodiment of the refrigerant evaporator 1 will be described. Hereinafter, differences from the first embodiment will be mainly described.

As shown in fig. 11, the windward distribution box 13 and the leeward collection box 23 of the present embodiment are integrally formed. Specifically, the windward distribution box 13 and the leeward collection box 23 are configured to include a core plate 61 and a box main body 62.

The tubes 12a of the upwind side heat exchange portion 12 and the tubes 22a of the downwind side heat exchange portion 22 are inserted and joined to the core plate 61. The core plate 61 is formed into a substantially W-shaped cross section. Specifically, the core plate 61 has an upwind side tube joint surface 611 and a downwind side tube joint surface 612. The pipe 12a of the windward side heat exchange unit 12 is inserted into and joined to the windward side pipe joining surface 611. The tube 22a of the leeward heat exchange portion 22 is inserted into and joined to the leeward tube joining surface 612. The core plate 61 has a core plate-side protrusion 613 disposed between the two pipe

joint surfaces

611, 612. Core-plate-side projection 613 projects on the opposite side of

heat exchange portions

12 and 22 from both

tube joining surfaces

611 and 612. The core-side protrusion 613 has a plurality of openings 613a formed in the longitudinal direction of the core-side protrusion 613, that is, in a direction perpendicular to both the air flow direction X and the vertical directions Y1 and Y2.

The tank main body portion 62 and the core plate 61 together constitute a space in the tank. The spaces in the boxes represent the first distribution portion 131 and the second distribution portion 132 of the windward distribution box 13 and the first collection portion 231 and the second collection portion 232 of the leeward collection box 23 shown in fig. 2. The tank main body 62 is formed in a substantially W-shaped cross section. Specifically, the case main body 62 includes an upwind side case main body 621 and a downwind side case main body 622. The windward case body 621 and the windward pipe joint surface 611 together constitute the first distribution portion 131 and the second distribution portion 132. The leeward tank body 622 and the leeward pipe joint surface 612 together form the first collecting portion 231 and the second collecting portion 232. The tank body 62 has a tank body side protrusion 623 disposed between the two

tank bodies

621 and 622. The tank body side convex portion 623 protrudes toward the upstream side heat exchange portion 12 and the downstream side heat exchange portion 22 from the two

tank bodies

621 and 622. A plurality of openings 623a are formed in the box main body side convex portion 623 along the longitudinal direction of the box main body side convex portion 623, i.e., the direction orthogonal to both the air flow direction X and the vertical directions Y1, Y2.

The core-plate-side projection 613 of the core 61 is engaged with the tank main body-side projection 623 of the tank main body 62. The space formed by the core 61 and the tank main body 62 is divided into the windward distribution tank 13 and the leeward collection tank 23. In other words, the core-plate-side protrusion 613 and the tank main-body-side protrusion 623 function as the coupling portion 70 that couples the windward distribution tank 13 and the leeward collection tank 23.

The opening 613a and the opening 623a are disposed so as to overlap at least a part of each other. Thus, the opening 613a and the opening 623a function as drain holes for draining condensed water generated on the outer surfaces of the windward heat exchange portion 12 and the leeward heat exchange portion 22 by heat exchange between the refrigerant and the air.

A space CL2 is formed between the upper portion of replacement tank 30 and tank main body 62. The space CL2 communicates with the space in which the windward heat exchange unit 12 and the leeward heat exchange unit 22 are arranged via the opening 613a and the opening 623 a. Space CL2 is disposed vertically below opening 613a and opening 623a on the Y1 side.

When the tank main body 62 is attached to the core plate 61, a joint 621a and a joint 622a are formed on the outer surface of the tank main body 62 located on the outer side. The engaging portion 621a is a portion that engages with the engaging portion 304 of the replacement tank 30. The engaging portion 622a is a portion that engages with the engaging portion 305 of the replacement box 30.

At a position of joint 621a corresponding to drain groove 310 of joint 304 of replacement tank 30, a drain groove 621b is formed. The drain groove 310 is formed at the joint portion 304 of the replacement tank 30 by the space surrounded by the drain groove 310 and the drain groove 621b to form the linear drain passage 40. The drain passage 40 is formed below the

openings

613a and 623a, and the

openings

613a and 623a are formed in the coupling portion 70. An inflow port 41 that opens into the space CL2 is formed at one end of the drain passage 40. A discharge port 42 that opens into a space on the vertical lower Y1 side of the windward side distributor box 13 is formed at the other end of the drain passage 40. The discharge port 42 is disposed vertically below the space CL2 on the Y1 side. The space in which the windward heat exchange portion 12 and the leeward heat exchange portion 22 are arranged communicates with the drain passage 40 via the opening 613a, the opening 623a, and the space CL 2.

A drain groove 622b is formed in the joint 622a at a position corresponding to the drain groove 311 of the joint 305 of the replacement tank 30. The space surrounded by the

drain grooves

311 and 622b forms the linear drain passage 50, and the drain grooves 311 are formed in the joint portion 305 of the replacement tank 30. The drain passage 50 is formed below the

openings

613a and 623a, and the

openings

613a and 623a are formed in the coupling portion 70. An inflow port 51 opening to the space CL2 is formed at one end of the drain passage 50. A discharge port 52 that opens into a space on the vertically lower Y1 side of the leeward collection tank 23 is formed at the other end portion of the drain passage 50. The outlet 52 is disposed vertically below the space CL2 on the Y1 side. The space in which the windward heat exchange portion 12 and the leeward heat exchange portion 22 are arranged communicates with the drain passage 50 via the opening 613a, the opening 623a, and the space CL 2.

At least one of the inflow port 41 of the drain passage 40 and the inflow port 51 of the drain passage 50 has a larger cross-sectional area than the opening area of each of the opening 613a and the opening 623 a. This can improve drainage of the condensed water flowing into space CL2 from opening 613a and opening 623 a. From the viewpoint of drainage of condensed water, the cross-sectional area of the discharge port 42 of the drain passage 40 is preferably larger than the cross-sectional area of the inflow port 41 of the drain passage 40. Similarly, the cross-sectional area of the discharge port 52 of the drain channel 50 is preferably larger than the cross-sectional area of the inflow port 51 of the drain channel 50.

Although not shown, the following through-holes are formed in the joint 621a in the same manner as in the first embodiment: the through-holes constituting the flow path for guiding the refrigerant in replacement tank 30 to first distribution portion 131, and the through-holes constituting the flow path for guiding the refrigerant in replacement tank 30 to second distribution portion 132. Similarly, although not shown, the following through-holes are formed in the joint portion 622 a: the through-holes that constitute the flow paths for guiding the refrigerant in the first collecting portion 231 to the replacement tank 30, and the through-holes that constitute the flow paths for guiding the refrigerant in the second collecting portion 232 to the replacement tank 30.

According to the refrigerant evaporator 1 of the present embodiment described above, the following operations and effects (3) and (4) can be obtained.

(3) In the refrigerant evaporator 1 of the present embodiment, when condensed water is generated on the outer surfaces of the upper-wind side heat exchange portion 12 and the lower-wind side heat exchange portion 22 by heat exchange between the refrigerant and the air, the condensed water flows vertically downward Y1 and passes through the opening 613a and the opening 623 a. The condensed water passing through the opening 613a and the opening 623a flows into the space CL2 and is discharged to the outside through the drain passage 40 and the drain passage 50. This can more reliably suppress frost cracking.

(4) At least one of the inflow port 41 of the drain passage 40 and the inflow port 51 of the drain passage 50 has a larger cross-sectional area than the opening area of each of the opening 613a and the opening 623 a. This makes it possible to more easily discharge the condensed water.

< other embodiment >

The refrigerant evaporator 1 of each embodiment may have only one of the drain passage 40 and the drain passage 50.

The fluid to be cooled in the refrigerant evaporator 1 is not limited to air, and an appropriate fluid can be used.

The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. The configurations of the above embodiments are merely examples, and are not limited to these descriptions. The scope of the present invention is indicated by the scope of claims, and further includes all modifications within the scope and meaning equivalent to the scope of claims. For example, the elements included in the specific examples described above, and the arrangement, materials, conditions, shapes, sizes, and the like thereof are not limited to the examples, and can be appropriately changed. The elements of the above embodiments can be combined to the extent technically possible.

Claims

1. A refrigerant evaporator (1) that exchanges heat between a fluid to be cooled and a refrigerant, comprising:

a first heat exchange portion (12) through the inside of which the refrigerant flows, the first heat exchange portion performing heat exchange between the fluid to be cooled and the refrigerant;

a second heat exchange portion (22) that is disposed opposite to the first heat exchange portion and through which the refrigerant flows, the second heat exchange portion exchanging heat between the fluid to be cooled and the refrigerant;

a first tank (13) that is disposed below the first heat exchange portion and distributes the refrigerant to the first heat exchange portion;

a second tank (23) that is disposed below the second heat exchange unit and collects the refrigerant flowing through the second heat exchange unit; and

a third tank (30) that is joined with the first tank and the second tank and that guides the refrigerant collected to the second tank to the first tank, wherein,

a clearance (CL1) is formed between the first tank, the second tank and the third tank,

drainage channels (40, 50) that drain water accumulated in the gaps are formed in both of the joints (133, 304) of the first tank and the third tank and the joints (233, 305) of the second tank and the third tank,

an inflow port (41) that opens to the clearance (CL1) is formed at one end of a drain passage formed at a joint between the first tank and the third tank,

an inflow port (51) that opens to the clearance (CL1) is formed at one end of a drain passage formed at a joint between the second tank and the third tank,

the sectional area of the discharge port of the drainage channel is larger than that of the inflow port of the drainage channel.

2. A refrigerant evaporator as recited in claim 1,

the discharge port of the drain passage is located at a position lower than the gap.

3. A refrigerant evaporator according to claim 1 or 2,

the drainage channel is provided with an arc-shaped water channel.

4. A refrigerant evaporator according to claim 1 or 2,

the drain passage has a linear water passage.

5. A refrigerant evaporator according to claim 1 or 2,

the cross-sectional area of the inflow port of the drain passage is larger than the cross-sectional area of the gap between the first tank and the second tank at the closest portion.

6. A refrigerant evaporator (1) that exchanges heat between a fluid to be cooled and a refrigerant, comprising:

a second tank (23) that is disposed below the second heat exchange unit and collects the refrigerant flowing through the second heat exchange unit;

a coupling portion (70) that couples the first tank and the second tank; and

at least one opening (613a, 623a) is formed in the connecting portion,

drainage channels (40, 50) that are located below an opening formed in the connection portion and drain water that has passed through the opening are formed in both the joint portion (304, 621a) between the first tank and the third tank and the joint portion (305, 622a) between the second tank and the third tank,

an inflow port (41) that opens into a space (CL2) below the opening is formed at one end of the drain passage formed at the joint between the first tank and the third tank,

an inflow port (51) that opens into a space (CL2) below the opening is formed at one end of the drain passage formed at the joint between the second tank and the third tank,

7. A refrigerant evaporator as recited in claim 6,

the cross-sectional area of the inflow port of the drain passage is larger than the opening area of the opening.