Heat exchanger for cooling

Abstract

To provide a novel heat exchanger for cooling capable of stably preventing distortion of the heat exchanger for cooling even under a high temperature environment, for example, in the heat exchanger for cooling configured by combining a metallic member with a synthetic resin member.SOLUTION: In a heat exchanger 10 for cooling, a metal plate 14 superposed on a cooling target 12 and a resin member 18 comprising a recessed groove 16 are mutually superposed and fixed and an opening 20 of the recessed groove 16 is covered by the metal plate 14, to form a cooling passage 22 in which a heat medium flows between the metal plate 14 and the resin member 18. An adhesive layer 46 is formed between superposed surfaces of the metal plate 14 and the resin member 18. The metal plate 14 and the resin member 18 are fixed at a portion outside of the cooling passage 22 by the adhesive layer 46. A deformation amount allowable to breakage of an outer peripheral region 56 in the adhesive layer 46 is made larger than that of a central portion 58 in the adhesive layer 46.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a cooling heat exchanger that is installed in, for example, an electric vehicle or a hybrid vehicle and cools an object to be cooled, such as a battery pack. [Background technology]

[0002] Conventionally, cooling devices have been proposed for cooling heat-generating elements such as batteries installed in electric vehicles, hybrid vehicles, etc., and such a cooling device is described, for example, in JP 2020-88108 A (Patent Document 1).

[0003] The cooling device described in Patent Document 1 comprises a metal cooling panel that is overlaid on the heat generating element to be cooled, and a resin flow path for flowing a refrigerant, and the opening of a groove provided in the resin flow path is covered by the metal cooling panel to form a cooling flow path for the refrigerant to flow. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-88108 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the difference in linear expansion coefficient between the metal member and the synthetic resin member is relatively large, and when heat is applied to both members, the synthetic resin member expands more easily than the metal member. Therefore, in a cooling device such as that described in Patent Document 1, for example, due to heat generated by the heating element or when the vehicle is exposed to a high-temperature environment, the synthetic resin member expands more than the metal member, causing the cooling device to distort and possibly causing the refrigerant to leak from the cooling device.

[0006] The present invention has been made against the background of the above-mentioned circumstances, and an object of the present invention is to provide a novel cooling heat exchanger that combines metal components and synthetic resin components and that can stably prevent distortion of the cooling heat exchanger even in a high-temperature environment, for example. [Means for solving the problem]

[0007] In view of the above problems, the present inventors have conceived of providing an adhesive layer between the overlapping surfaces of a metal plate, which is a member made of metal, and a resin member, which is a member made of synthetic resin, and suppressing distortion of a cooling heat exchanger by the adhesive effect of the adhesive layer. However, it was found that when the resin member deforms so as to extend more than the metal plate in a high-temperature environment, the outer peripheral region of the adhesive layer cannot follow the deformation of the resin member and breaks with an inexpensive adhesive. To solve this problem, it is possible to adopt an adhesive that can follow the deformation of the resin member, but such an adhesive is expensive, and it is not realistic in terms of cost to adopt such an expensive adhesive over the entire surface between the overlapping surfaces of the metal plate and the resin member. Therefore, the object of the present invention is to reduce costs when an adhesive layer is provided between the overlapping surfaces of the metal plate and the resin member, in addition to the above.

[0008] The following describes preferred embodiments for understanding the present invention, but the embodiments described below are merely illustrative and may be combined with one another as appropriate, and the multiple components described in each embodiment may be recognized and used independently as far as possible, and may also be combined with any of the components described in another embodiment as appropriate. As a result, the present invention is not limited to the embodiments described below, and various other embodiments may be realized.

[0009] The first aspect is a heat exchanger for cooling in which a metal plate to be placed on an object to be cooled and a resin member having a groove are placed on top of and fixed to each other, and the opening of the groove is covered by the metal plate to form a cooling flow path through which a heat transfer medium flows between the metal plate and the resin member, and an adhesive layer is formed between the overlapping surfaces of the metal plate and the resin member, and the metal plate and the resin member are fixed by the adhesive layer at portions outside the cooling flow path, and the peripheral region of the adhesive layer is allowed to deform to a greater extent before breaking than the central portion of the adhesive layer.

[0010] According to this embodiment, the outer peripheral region and the central portion of the adhesive layer are different in form, and the outer peripheral region is allowed to deform to a greater extent than the central portion before breaking. That is, even in a high-temperature environment, the central portion of the adhesive layer is not substantially affected by the stretching deformation of the resin member, and the amount of deformation allowed before breaking is relatively small, while the outer peripheral region is allowed to deform to a greater extent before breaking so as to follow the stretching deformation of the resin member. This maintains the adhesive state between the metal plate and the resin member even in a high-temperature environment, and stably prevents distortion of the cooling heat exchanger. In addition, as a method of making the outer peripheral region and the central portion of the adhesive layer different in form, for example, the second and third embodiments described below can be considered, which can stably reduce costs.

[0011] In a second aspect, in the cooling heat exchanger according to the first aspect, a thick-walled bonding area is provided in the outer peripheral region of the adhesive layer, which is thicker than the central portion of the adhesive layer.

[0012] According to this embodiment, the outer peripheral region of the adhesive layer is provided with a thick-walled bonding region that is thicker than the central portion, so that the deformation tolerance of the outer peripheral region can be made larger than that of the central portion. The adhesive layer may be made of a single material (i.e., an expensive adhesive) throughout, and the central portion is made thinner than the outer peripheral region, thereby reducing costs compared to a case in which the thickness is the same as that of the outer peripheral region throughout. This embodiment may also be combined with the third embodiment, and the central portion of the adhesive layer may be made of an inexpensive adhesive.

[0013] In a third aspect, in the cooling heat exchanger according to the first or second aspect, the outer peripheral region and the central portion of the adhesive layer are made of different types of adhesive.

[0014] According to this embodiment, since the outer peripheral region and the central portion of the adhesive layer are made of different types of adhesive, for example, the outer peripheral region of the adhesive layer can be made of an expensive adhesive that can follow the expansion and deformation of the resin member, and the central portion can be made of an inexpensive adhesive with a small deformation tolerance, thereby reducing costs compared to when the entire layer is made of an expensive adhesive. Effect of the Invention

[0015] According to the present invention, it is possible to provide a heat exchanger for cooling that can stably prevent leakage of refrigerant even in a high-temperature environment and can reduce costs. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a perspective view showing a cooling heat exchanger according to a first embodiment of the present invention; [Diagram 2] FIG. 2 is an exploded perspective view of the cooling heat exchanger shown in FIG. 1; [Diagram 3] FIG. 2 is a perspective view showing a metal plate constituting the cooling heat exchanger shown in FIG. 1; [Figure 4] FIG. 2 is a perspective view showing a resin member constituting the cooling heat exchanger shown in FIG. 1; [Diagram 5] FIG. 2 is a vertical cross-sectional view showing a model of the cooling heat exchanger shown in FIG. 1, illustrating a state before the cooling heat exchanger is expanded and deformed by heat; [Figure 6] FIG. 2 is a vertical cross-sectional view showing a model of the cooling heat exchanger shown in FIG. 1, illustrating a state after the cooling heat exchanger has expanded and deformed due to heat; [Figure 7] FIG. 11 is a longitudinal sectional view showing a model of a cooling heat exchanger according to a second embodiment of the present invention, illustrating a state before the cooling heat exchanger is expanded and deformed by heat; [Figure 8] FIG. 8 is a vertical cross-sectional view showing a model of the cooling heat exchanger shown in FIG. 7, illustrating a state after the cooling heat exchanger has expanded and deformed due to heat. [Figure 9] FIG. 13 is a vertical cross-sectional view showing a model of a cooling heat exchanger according to a third embodiment of the present invention, illustrating a state before the cooling heat exchanger is expanded and deformed by heat. [Figure 10] FIG. 10 is a vertical cross-sectional view showing a model of the cooling heat exchanger shown in FIG. 9, illustrating a state after the cooling heat exchanger has expanded and deformed due to heat. [Figure 11] FIG. 1 is a vertical cross-sectional view showing a model of a cooling heat exchanger according to another embodiment of the present invention, illustrating a state before the cooling heat exchanger is expanded and deformed by heat. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] In order to clarify the present invention more specifically, embodiments of the present invention will be described in detail below with reference to the drawings.

[0018] 1 and 2 show a cooling heat exchanger 10 as a first embodiment of the present invention. This cooling heat exchanger 10 is provided in, for example, an electric vehicle, a hybrid vehicle, or the like, and is superimposed on a cooling target 12 (shown by a two-dot chain line in FIG. 1) such as a battery pack that generates heat in the electric vehicle, the hybrid vehicle, or the like, to cool the cooling target 12. In the following description, the vertical direction basically refers to the vertical direction in FIG. 1, which is the superimposed direction of the cooling heat exchanger 10 and the cooling target 12.

[0019] More specifically, in the cooling heat exchanger 10, a metal plate 14 that is placed on the object to be cooled 12 and a plate-shaped resin member 18 having a groove 16 are placed on top of each other and fixed to each other, and the opening (upper opening 20) of the groove 16 is covered by the metal plate 14, thereby forming a cooling flow path 22 through which a heat transfer medium (refrigerant) flows between the metal plate 14 and the resin member 18.

[0020] The metal plate 14 is preferably made of a metal having excellent thermal conductivity, such as copper (including copper alloys) or aluminum (including aluminum alloys). In this embodiment, the metal plate 14 is made of aluminum. In particular, as shown in FIG. 3 and other figures, the metal plate 14 is a substantially rectangular plate, and the four peripheral sides are composed of a pair of long sides 24, 24 and a pair of short sides 26, 26 connecting the long sides 24. The thickness of the metal plate 14 is not limited, but in this embodiment, it is made relatively thin.

[0021] Furthermore, the metal plate 14 may have through holes 28 (shown by two-dot chain lines in FIGS. 1 to 3) that penetrate the metal plate 14 in the plate thickness direction at positions corresponding to an inlet portion 40 and an outlet portion 42 (described later) in the overlapping resin member 18. Such through holes 28 may be provided, for example, at two diagonally opposing positions (for example, on both the left and right sides in FIG. 3) among the four corners of the metal plate 14 that has a substantially rectangular plate shape.

[0022] The resin member 18 is made of a hard synthetic resin, and may be made of, for example, a fiber-reinforced synthetic resin. As shown in FIG. 4 and the like, the resin member 18 has a certain thickness and is a substantially rectangular plate having a planar shape substantially corresponding to that of the metal plate 14. That is, the resin member 18 also has a pair of long sides 30, 30 and a pair of short sides 32, 32, and the metal plate 14 and the resin member 18 are overlapped with each other such that the longitudinal direction of the metal plate 14 and the longitudinal direction of the resin member 18 are aligned. In this embodiment, the metal plate 14 and the resin member 18 are formed to have substantially the same size in a plan view, and when the metal plate 14 and the resin member 18 are overlapped with each other, the pair of long sides 24, 24 of the metal plate 14 and the pair of long sides 30, 30 of the resin member 18 are overlapped with each other, and the pair of short sides 26, 26 of the metal plate 14 and the pair of short sides 32, 32 of the resin member 18 are overlapped with each other.

[0023] The resin member 18 is formed with a groove 16 that opens upward (having an upper opening 20). The groove 16 is formed with a depth dimension that does not penetrate the resin member 18 in the plate thickness direction (vertical direction), and is a groove shape with a bottom. The shape of the groove 16 is not limited, but the groove 16 of this embodiment has a plurality of passages 34 extending parallel to the long side 30 of the resin member 18 in parallel. A partition portion 36 extending parallel to the long side 30 of the resin member 18 is provided between adjacent passages 34, 34 in the parallel direction of the passages 34. The passages 34 are connected at both ends in the length direction of each passage 34 by a connection passage 38 that extends in a direction perpendicular to the length direction of each passage 34 (parallel to the short side 32 of the resin member 18).

[0024] In particular, in this embodiment, the outermost passages 34 in the parallel direction of the passages 34 extend beyond the connecting passages 38 on one side in the length direction, and the inlet portion 40 and the outlet portion 42 are formed by the portions of the outermost passages 34 in the parallel direction that extend beyond the connecting passages 38. The positions of the inlet portion 40 and the outlet portion 42 are not limited, but in this embodiment, the inlet portion 40 is formed on the left side of the groove 16 in Figure 4, and the outlet portion 42 is formed on the right side in Figure 4.

[0025] Further, the portion of the resin member 18 where the groove 16 is not formed is a frame-shaped portion 44 surrounding the groove 16 on all four sides. That is, the frame-shaped portion 44 includes a portion outside the outermost passages 34 in the direction in which the short side 32 of the resin member 18 extends, and a portion outside the connection passages 38 in the direction in which the long side 30 of the resin member 18 extends. Note that each passage 34 and each partition portion 36 is formed to have a relatively long length in the direction in which the long side 30 of the resin member 18 extends. Therefore, the groove 16 is formed to have a shape whose longitudinal direction is the direction in which the long side 30 of the resin member 18 extends.

[0026] The metal plate 14 is placed on the resin member 18 having the above-mentioned structure from above, and the resin member 18 and the metal plate 14 are fixed to each other. The resin member 18 and the metal plate 14 are fixed to each other by adhesion, and an adhesive layer 46 (see FIG. 5) is formed between the overlapping surfaces of the metal plate 14 and the resin member 18 (the lower surface 45a of the metal plate 14 and the upper surface 45b of the resin member 18). By fixing the metal plate 14 and the resin member 18 to each other via the adhesive layer 46, the opening (upper opening 20) of the recessed groove 16 is liquid-tightly sealed by the metal plate 14.

[0027] Specifically, the upper surface of the frame-shaped portion 44 of the resin member 18 and the upper surfaces of the partition portions 36 are superimposed on the metal plate 14 via the adhesive layer 46, thereby covering the upper openings 20 of the passages 34 and the connecting passages 38 to form tunnel-shaped passages. That is, the upper openings 20 of the passages 34 are covered to form a plurality of tunnel-shaped passages parallel to each other in the short side 32 direction of the resin member 18, and each of these tunnel-shaped passages is connected to a tunnel-shaped passage formed by covering the upper openings 20 of the connecting passages 38 and extending in the short side 32 direction. As a result, each of the tunnel-shaped passages is connected to each other to form the cooling passage 22 through which the refrigerant flows. In other words, the metal plate 14 and the resin member 18 are fixed by the adhesive layer 46 at a position outside the cooling passage 22.

[0028] The adhesive layer 46 is provided, for example, over the entire surface of the lower surface 45a of the metal plate 14, and is formed to have a substantially rectangular area in a plan view. The method of providing the adhesive layer 46 on the lower surface 45a of the metal plate 14 is not limited, and any known method may be used, such as application with a brush or spraying, or immersion in the material of the adhesive layer 46 before hardening.

[0029] Here, when through holes 28 are formed in the metal plate 14 at positions corresponding to the inlet portion 40 and the outlet portion 42, the cooling passage 22 communicates with the external space through these through holes 28. In this case, the inlet portion 40 and the through hole 28 provided at the position corresponding to the inlet portion 40 form an inlet 48 for allowing the coolant to flow into the cooling passage 22 from the outside, and the outlet portion 42 and the through hole 28 provided at the position corresponding to the outlet portion 42 form an outlet 50 for allowing the coolant to flow out of the cooling passage 22 to the outside.

[0030] The refrigerant flowing through the cooling flow passage 22 is not limited, but may be chiller water used in a chiller (cooling water circulation system) conventionally provided in a vehicle, and specifically may be water, alcohol (methanol, ethanol, etc.), glycol, etc. In addition, the refrigerant source of the refrigerant flowing through the cooling flow passage 22 is not limited, but may be, for example, a separate chiller including a pump (not shown) or a chiller already installed in the vehicle. By employing a chiller including a pump as the refrigerant source, the refrigerant can be caused to flow through the cooling flow passage 22.

[0031] In the metal plate 14 in the cooling heat exchanger 10 configured in this manner, a heat generating body (cooling target 12) that generates heat when electricity is applied, such as a battery pack, is placed on the surface (upper surface) opposite to the surface on which the resin member 18 is superimposed. In addition, for example, when the metal plate 14 is provided with the through holes 28 to form the inlet 48 and the outlet 50, an inlet side tube 52 is connected to the inlet 48 on the upper surface of the metal plate 14, and one end of the inlet side tube 52 extends to the outside of the cooling heat exchanger 10 and is connected to a refrigerant source (not shown). Furthermore, an outlet side tube 54 is connected to the outlet 50, and one end of the outlet side tube 54 extends to the outside of the cooling heat exchanger 10 and is connected to a refrigerant source (not shown). That is, in the cooling heat exchanger 10 of this embodiment, a circulation system is configured in which the refrigerant that flows from the refrigerant source through the inlet tube 52 flows into the cooling flow passage 22 from the inlet 48, flows inside the cooling flow passage 22, and then returns to the refrigerant source through the outlet 50 and the outlet tube 54. Note that these inlet and outlet tubes 52, 54 are provided, for example, at positions on the upper surface of the metal plate 14 away from the target 12 to be cooled.

[0032] In the cooling heat exchanger 10 having such a structure, when a heat generating body (subject to be cooled 12) such as a battery pack is placed on the metal plate 14, the subject to be cooled 12 generates heat, and the heat generated in the subject to be cooled 12 is transferred to the metal plate 14. The heat transferred to the metal plate 14 is cooled (heat exchanged) by the refrigerant flowing in each cooling flow passage 22, and a rise in temperature of the subject to be cooled 12 and the metal plate 14 is prevented. Meanwhile, the refrigerant that flows into the cooling flow passage 22 from each inlet 48 is heated as it flows through the cooling flow passage 22, and flows out of each outlet 50 at a higher temperature than when it flowed in from each inlet 48, and reaches a refrigerant source (not shown). In this refrigerant source, the refrigerant is cooled again, and flows into the cooling flow passage 22 through each inlet 48.

[0033] That is, when the object to be cooled 12 generates heat and the coolant flows in each cooling flow passage 22, the temperature of the coolant rises, and the temperature of the resin member 18 constituting each cooling flow passage 22 also rises. Alternatively, the temperature of the cooling heat exchanger 10 rises when the vehicle is exposed to a high temperature environment. In such a temperature change, the difference in linear expansion coefficient between the metal plate 14, which is a member made of metal, and the resin member 18, which is a member made of synthetic resin, is relatively large, and the resin member 18 expands more than the metal plate 14. This could cause distortion in a cooling heat exchanger having a conventional structure.

[0034] Here, the longitudinal section of the cooling heat exchanger 10 of this embodiment is shown in a model in FIG. 5. Note that the drawings from FIG. 5 onwards show the cooling heat exchangers 10, 60, 70, and 80 in a model, and the thickness dimensions of each member may be exaggerated for ease of understanding. In FIG. 5, the cooling heat exchanger 10 is shown in a state where it is not in a high-temperature environment. As described above, the cooling heat exchanger 10 is formed by overlapping and fixing the metal plate 14 and the resin member 18 via the adhesive layer 46. The part shown by the two-dot chain line in FIG. 5 is the formation region of the groove 16. That is, the formation region of the groove 16 includes each passage 34, each partition portion 36, and each connection passage 38. The formation region of the groove 16 is formed in the central part of the resin member 18. Furthermore, the part of the resin member 18 on the outer periphery side of the formation region of the groove 16 is the frame-shaped part 44.

[0035] In this embodiment, as shown in FIG. 5, the upper surface of the region where the groove 16 is formed is located above the upper surface of the surrounding portion (the frame-shaped portion 44). That is, in this embodiment, the upper surface of each partition portion 36 is located above the upper surface of the frame-shaped portion 44. As a result, the opposing distance in the up-down direction between the metal plate 14 and the resin member 18 is larger in the outer peripheral region (the region where the frame-shaped portion 44 is formed) than in the central portion (the region where the groove 16 is formed), and the thickness dimension of the adhesive layer 46 provided between the metal plate 14 and the resin member 18 is larger in the outer peripheral region than in the central portion. As a result, the outer peripheral region of the adhesive layer 46 is provided with a thick-walled bonding region 56 that is thicker than the central portion of the adhesive layer 46, and the central portion is provided with a thin-walled bonding region 58 that is thinner than the outer peripheral region (the thick-walled bonding region 56). In other words, the outer peripheral region of the adhesive layer 46 is constituted by the thick-walled bonding region 56, and the central portion is constituted by the thin-walled bonding region 58. The thick bonding region 56 extends continuously in an annular shape around the entire outer circumferential region of the adhesive layer 46 in the circumferential direction.

[0036] The thickness of the thick-walled bonding region 56 does not have to be constant in the circumferential direction, and if it is thicker than the central portion of the adhesive layer 46, the thickness of the thick-walled bonding region 56 may vary in the circumferential direction, and the height position on the upper surface of the frame-shaped portion 44 may vary in the circumferential direction accordingly. Similarly, if the thickness of the central portion of the adhesive layer 46 is thinner than the thick-walled bonding region 56, the thickness of the central portion of the adhesive layer 46 may vary partially, and the height position on the upper surface of each partition portion 36 may vary partially accordingly. In addition, the thick-walled bonding region 56 may be provided only in the portion above the frame-shaped portion 44 in the resin member 18, or may be provided across the portion of the passage 34 on the inner periphery side of the frame-shaped portion 44 and the portion of the partition portion 36.

[0037] As a result, the adhesive layer 46 is formed thicker in the outer peripheral region than in the central portion, and the outer peripheral region (thick joint region 56) of the adhesive layer 46 is allowed to deform more until it breaks than the central portion of the adhesive layer 46. Therefore, as shown in FIG. 6, when the cooling target 12 in the cooling heat exchanger 10 generates heat or when the vehicle is exposed to a high-temperature environment, the resin member 18 expands more than the metal plate 14. However, since the thick joint region 56 is provided in the outer peripheral region, the adhesive layer 46 constituting the thick joint region 56 can deform in accordance with the expansion and deformation of the resin member 18 without breaking. As a result, the adhesive layer 46 maintains the adhesive effect between the metal plate 14 and the resin member 18, and distortion of the metal plate 14 due to the expansion and deformation of the resin member 18 can be effectively prevented.

[0038] As the adhesive that constitutes the adhesive layer 46 that can deform in accordance with the expansion and deformation of the resin member 18 in this manner, for example, a urethane-based adhesive or a mixture of an epoxy-based and a silicone-based adhesive can be used, and a specific example is "EP001K" manufactured by Cemedine Co., Ltd.

[0039] The above adhesive is relatively expensive, but in the adhesive layer 46 of this embodiment, the central portion is made thinner than the peripheral region (thick joint region 56), so that costs can be reduced compared to, for example, providing the adhesive layer with the same thickness as the thick joint region over the entire surface. That is, in this embodiment, only the peripheral portion of the adhesive layer 46 that needs to be stretched to follow the resin member 18 is made thick to provide the thick joint region 56, and the central portion does not need to stretch and is therefore made thinner than the peripheral portion, thereby achieving both prevention of breakage in the adhesive layer 46 and cost reduction.

[0040] Next, FIG. 7 shows a vertical cross section of a cooling heat exchanger 60 according to a second embodiment of the present invention. In FIG. 7, the cooling heat exchanger 60 is shown in a state where it is not in a high-temperature environment, and the formation area of ​​the recessed groove 16 is shown by a two-dot chain line. In this embodiment, the adhesive layer 64 located between the metal plate 14 and the resin member 62 is formed with a substantially constant thickness throughout. The thickness of the adhesive layer 64 can be, for example, substantially equal to the thickness of the thick-walled joint area 56 of the adhesive layer 46 in the first embodiment. The resin member 62 in this embodiment has a shape similar to that of the resin member 18 in the first embodiment, but the thickness of the resin member 62 other than the recessed groove 16 (each passage 34 and each connection passage 38) is substantially constant, and the upper surface of each partition portion 36 is located at substantially the same height as the upper surface of the frame-shaped portion 44 in the vertical direction.

[0041] Here, in this embodiment, the outer peripheral region and the central portion of the adhesive layer 64 are made of different types of adhesive. That is, in this embodiment, the adhesive layer 64 is made up of a first adhesive layer 66 constituting the outer peripheral region and a second adhesive layer 68 constituting the central portion. And, as the first adhesive layer 66, an adhesive capable of deforming to follow the expansion and deformation of the resin member 18, which was adopted in the adhesive layer 46 in the first embodiment, is adopted. As a result, as shown in FIG. 8, even when the cooling heat exchanger 60 is exposed to a high-temperature environment and the resin member 62 expands and deforms, the outer peripheral region of the adhesive layer 64 (the first adhesive layer 66) deforms to follow the expansion of the resin member 62, and the adhesive layer 64 is prevented from breaking.

[0042] On the other hand, since the second adhesive layer 68 is not significantly affected by the expansion and deformation of the resin member 18, there is no need to consider the allowable deformation until breakage when selecting an adhesive, and various well-known adhesives such as epoxy-based, acrylic-based, urethane-based, and silicone-based adhesives can be used, and a specific example is "WS-222" manufactured by Sika Hamatite Co., Ltd.

[0043] The adhesive used in the second adhesive layer 68 is less expensive than the adhesive used in the first adhesive layer 66, and costs can be reduced compared to, for example, a case in which the adhesive used in the first adhesive layer is used throughout the entire adhesive layer. Therefore, in this embodiment as well, prevention of breakage in the adhesive layer 64 and cost reduction can be achieved at the same time.

[0044] Next, FIG. 9 shows a model of a longitudinal section of a cooling heat exchanger 70 according to a third embodiment of the present invention. In the cooling heat exchanger 70 of this embodiment, the shapes of the metal plate 14 and the resin member 18 are the same as those of the first embodiment, but the mode of the adhesive layer 72 is different from that of the first embodiment. That is, in the adhesive layer 72 of this embodiment, the outer peripheral region and the central portion of the adhesive layer 72 are made of different types of adhesive, as in the second embodiment, and the adhesive layer 72 is made up of a first adhesive layer 66 constituting the outer peripheral region and a second adhesive layer 74 constituting the central portion. The first adhesive layer 66 in this embodiment may be the same as that in the second embodiment.

[0045] In particular, in this embodiment, the thickness dimensions of the central portion and the outer peripheral portion of the adhesive layer 72 are different from each other, and the outer peripheral portion of the adhesive layer 72 is thicker than the central portion. As a result, in this embodiment, the thick-walled bonding region provided in the outer peripheral portion of the adhesive layer 72 is formed by the first adhesive layer 66, and the thin-walled bonding region provided in the central portion is formed by the second adhesive layer 74. As a result, as shown in FIG. 10, even when the cooling heat exchanger 70 is exposed to a high-temperature environment and the resin member 18 is deformed more than the metal plate 14, the first adhesive layer 66 follows and deforms, so that the adhesive layer 72 can be prevented from breaking. Note that the second adhesive layer 74 in this embodiment is thinner than the second adhesive layer 68 in the second embodiment, but since it is not necessary to consider deformation following the expansion of the resin member 18 like the second adhesive layer 68, an adhesive similar to the second adhesive layer 68 can be used. In this embodiment, the second adhesive layer 74 is thinner than the second embodiment, so that further cost reduction is achieved.

[0046] Although the first to third embodiments of the present invention have been described in detail above, the present invention is in no way limited by the specific description of the embodiments, and can be implemented in various forms with various changes, modifications, improvements, etc. based on the knowledge of those skilled in the art, and it goes without saying that all such embodiments are included within the scope of the present invention as long as they do not deviate from the spirit of the present invention.

[0047] For example, in the first embodiment, the upper surface of the formation region of the groove 16 (i.e., the upper surface of each partition portion 36) is located above the upper surface of the frame-shaped portion 44, but this is not limited to this embodiment. That is, in the first embodiment, the vertical dimensions of the central portion and the outer peripheral portion of the resin member 18 are different, but the boundary between the central portion and the outer peripheral portion is not limited to the boundary between the groove 16 and the frame-shaped portion 44. For example, the portion of the outer peripheral portion of the resin member whose upper surface is located lower than the central portion (i.e., the portion where the thick-walled bonding region is provided in the adhesive layer) may extend not only to the frame-shaped portion but also to the partition portion located inside the groove. Conversely, the portion of the outer peripheral portion of the resin member whose upper surface is located lower than the central portion may be only the outer peripheral portion of the frame-shaped portion. The same applies to the third embodiment.

[0048] In the above embodiment, the metal plate 14 is provided with the through holes 28, and the inlet 48 and the outlet 50 open upward, but the present invention is not limited to this. For example, the resin member may have through holes in a bottom wall portion constituting the inlet and outlet portion, and the inlet and outlet may open downward from the resin member, or the peripheral wall portion constituting the inlet and outlet may have through holes and the inlet and outlet may open to the side of the resin member.

[0049] In the above embodiment, each groove 16 includes a plurality of parallel passages 34 and a connecting passage 38 connecting each of the passages 34, but the present invention is not limited to this. The opening (upper opening) of the groove is covered with a metal plate to form a cooling flow path, and the extension direction, length, width, depth, and other aspects of the cooling flow path can be set arbitrarily. However, from the viewpoint of cooling efficiency (heat exchange efficiency), it is preferable that the cooling flow path is provided over a wide area of ​​the resin member.

[0050] In the second and third embodiments, the central portion and the peripheral region of the adhesive layer 64, 72 are made of different types of adhesive, and the thickness dimension of the central portion (second adhesive layer 68, 74) is the same as or thinner than the thickness dimension of the peripheral region (first adhesive layer 66), but the thickness dimension of the central portion made of a relatively inexpensive adhesive may be made thicker than the thickness dimension of the peripheral region.

[0051] In the above embodiment, the adhesive layers 46, 64, 72 are provided over substantially the entire surface of the lower surface 45a of the metal plate 14 and have a substantially rectangular shape in a plan view, but the present invention is not limited to this. That is, the adhesive layer may be provided on the upper surface of the resin member, that is, on the upper surface of the frame-shaped portion or the partition portion, instead of or in addition to the lower surface of the metal plate. Even in such a case, it is sufficient to virtually imagine a rectangular adhesive layer including the adhesive layer provided on the upper surface of the frame-shaped portion or the partition portion, and to make the outer peripheral region of the rectangular adhesive layer (e.g., the adhesive layer provided on the upper surface of the frame-shaped portion) have a larger deformation amount until breakage than the central portion (e.g., the adhesive layer provided on the upper surface of the partition portion).

[0052] In the above embodiment, the metal plate 14 and the resin member 18 are formed to have substantially the same shape and substantially the same size in a plan view, but this is not limited to this embodiment. The metal plate and the resin member may have different shapes and sizes in a plan view. Even if the metal plate and the resin member are formed to have substantially the same shape and substantially the same size in a plan view, the metal plate and the resin member may be in a state of being shifted from each other, that is, they may be partially overlapped in a plan view rather than entirely. In any of the above cases, the opening of the groove provided in the resin member is covered by the metal plate to form a cooling flow path. These overlapping parts are the overlapping surfaces of both members, and the overlapping surfaces of the metal plate and the resin member are not limited to the entire lower surface of the metal plate or the entire upper surface of the resin member.

[0053] In the above embodiment, the central portion (thin joint region 58, second adhesive layer 68, 74) of adhesive layer 46, 64, 72 is made of one type of adhesive, but as in the cooling heat exchanger 80 shown in FIG. 11, the central portion of adhesive layer 82 may be made of multiple types of adhesive. That is, the adhesive layer 82 in this embodiment has a substantially constant thickness dimension over the entirety, and the same resin member 62 as in the second embodiment is used. And, adhesive layer 82 is made of multiple types of adhesive, and adhesive layer 82 is made of a first adhesive layer 84 and a second adhesive layer 86. The first adhesive layer 84 has a structure similar to that of adhesive layer 46 in the first embodiment, and a thick joint region 56 that is thicker is provided in the region on the outer periphery side of the thin joint region 58 in the thin central portion. A second adhesive layer 86 made of an adhesive that is less expensive than the first adhesive layer 84 is superimposed and fixed to the lower surface of the thin joint region 58 in the first adhesive layer 84. The first adhesive layer 84 and the second adhesive layer 86 ensure that the thickness dimension of the adhesive layer 82 is generally constant throughout.

[0054] Thus, in this embodiment, the central portion of the adhesive layer 82 is composed of the thin-walled bonding region 58 of the first adhesive layer 84 and the second adhesive layer 86, and the cooling heat exchanger 80 having such a structure can also exhibit the same effects as those of the above embodiment. In particular, by adopting a structure such as this embodiment, it is possible to provide the first adhesive layer 84 on the lower surface 45a of the metal plate 14 and the second adhesive layer 86 on the upper surface 45b of the resin member 62, for example, before the metal plate 14 and the resin member 62 are fixed to each other, and by bonding the first adhesive layer 84 and the second adhesive layer 86, it is possible to fix the metal plate 14 and the resin member 62 more firmly. Similarly, the central portion (second adhesive layer 68) of the adhesive layer 64 in the second embodiment can be composed of a plurality of inexpensive adhesives, and the adhesive layer adopted in the cooling heat exchanger according to the present invention may be composed of three or more types of adhesives.

[0055] In the above embodiment, the cooling heat exchangers 10, 60, 70 are mounted on an electric vehicle or a hybrid vehicle, and the object to be cooled 12 is a battery pack, but the present invention is not limited to this embodiment. For example, the heat generating body to be cooled may be an in-vehicle part other than a battery pack, or may be a part used in something other than a vehicle, and the cooling heat exchanger according to the present invention may be applied to a vehicle other than an electric vehicle or a hybrid vehicle, or to something other than a vehicle. [Explanation of symbols]

[0056] 10 Cooling heat exchanger (first embodiment) 12 Cooling target 14 Metal Plate 16 Groove 18 Resin parts 20 Upper opening (opening) 22 Cooling Channel 24 Long side 26 Short Side 28 Through hole 30 Long side 32 Short side 34 Passage 36 Partition 38 Connecting Passage 40 Inlet 42 Outflow 44 Frame-shaped part 45a (of metal plate) bottom surface (mating surface) 45b (of resin member) upper surface (mating surface) 46 Adhesive layer 48 Inlet 50 Outlet 52 Inlet tube 54 Outlet tube 56 Thick joint area (outer area) 58 Thin joint area (center part) 60 Cooling heat exchanger (second embodiment) 62 Resin parts 64 Adhesive layer 66 First adhesive layer (peripheral region) 68 Second adhesive layer (center part) 70 Cooling heat exchanger (third embodiment) 72 Adhesive layer 74 Second adhesive layer (center part) 80 Cooling heat exchanger (Fig. 11) 82 Adhesive layer 84 First adhesive layer 86 Second Adhesive Layer

Claims

1. A heat exchanger for cooling, comprising: a metal plate to be placed on an object to be cooled; and a resin member having a groove, which are placed on top of each other and fixed to each other; and an opening of the groove is covered with the metal plate, thereby forming a cooling flow path through which a heat medium flows between the metal plate and the resin member, an adhesive layer is formed between overlapping surfaces of the metal plate and the resin member, and the metal plate and the resin member are fixed to each other by the adhesive layer at a portion outside the cooling flow path; The adhesive layer has a peripheral region in which the amount of deformation permitted before breaking is greater than that of a central portion of the adhesive layer.

2. 2. The heat exchanger for cooling according to claim 1, wherein the adhesive layer has a thick-walled bonding area in the outer peripheral area, the thick-walled bonding area being thicker than the central area of ​​the adhesive layer.

3. 3. The heat exchanger for cooling according to claim 1, wherein the outer peripheral region and the central portion of the adhesive layer are formed of different types of adhesive.

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