Cooling heat exchanger

Abstract

To provide a heat exchanger for cooling having such a new constitution that it comprises: a metallic cooling surface constituent member to be superimposed on a cooling-target; and a synthetic resin flow path component overlaid on and fixed to the cooling surface component, and that the heat exchanger for cooling can tolerate the difference in the amount of deformation due to thermal expansion between the metallic cooling surface component and the synthetic resin flow path component.SOLUTION: A heat exchanger for cooling 10 has laminated structure in which a metallic cooling surface component 12 superimposed on a cooling object B and a synthetic resin flow path member 14 are superimposed on each other a cooling object B, and a cooling flow path 58 through which a heat transfer medium for cooling flows is formed between the superimposed surfaces of the cooling surface component member 12 and the flow path member 14. The cooling surface component member 12 and the flow path member 14 are bonded to each other in their outer circumferential regions by an elastic adhesive layer 54, and the cooling surface component member 12 and the flow path member 14 are fixed to each other by direct bonding without adhesive at a direct bonding portion 44 provided in the central region of the flow path member 14.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a cooling heat exchanger used for cooling a cooling target such as a battery pack in an electrified vehicle such as an electric vehicle.

Background Art

[0002] For example, in electrified vehicles such as electric vehicles and hybrid vehicles, heat-generating components such as battery packs and electronic devices to be cooled have an increasing heat generation amount due to miniaturization and high performance, and the importance of cooling performance is increasing. Conventionally, a cooling heat exchanger having a structure in which cooling channels are formed between mutually overlapping metal plates has been adopted. In this cooling heat exchanger, one plate is overlapped with a cooling target such as a battery pack, and the cooling target is cooled by the one plate being cooled by a refrigerant flowing through the cooling channel.

[0003] In addition, since there is a strong demand for weight reduction of vehicles in electrified vehicles, weight reduction of the cooling heat exchanger has also been studied. For example, International Publication No. 2020 / 196878 (Patent Document 1) proposes that one plate that is overlapped with a cooling target and for which thermal conductivity is important is made of metal, and the other plate for which thermal conductivity is not required is made of a resin member made of a synthetic resin having a specific gravity smaller than that of metal. In Patent Document 1, the resin member is a box body that opens on the upper surface, and a rib for forming a flow path is integrally provided in the box body.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, as a result of the inventor's study, it was found that in the structure of Patent Document 1, when the metal plate and the resin member are overlapped and fixed to each other by means such as adhesion, bending in the plate thickness direction occurs due to the difference in the linear expansion coefficient. Therefore, in an environment with extremely high or low temperatures, it was also considered that the cooling heat exchanger might bend due to the difference in the amount of deformation caused by the thermal expansion of the metal plate and the resin member, resulting in peeling between the metal plate and the resin member and a decrease in cooling performance. In particular, for a cooling heat exchanger used in an electrified vehicle, since the sizes in the length and width directions orthogonal to the overlapping direction of the metal plate and the resin member are large, the difference in the amount of deformation due to the difference in the linear expansion coefficient between the metal plate and the resin member tends to be a problem.

[0006] The problem to be solved by the present invention is to provide a cooling heat exchanger with a novel structure that can tolerate the difference in the amount of deformation due to the difference in the linear expansion coefficient between a metal cooling surface component that is overlapped with the object to be cooled and a synthetic resin flow path component that is overlapped and fixed to the cooling surface component.

Means for Solving the Problem

[0007] Hereinafter, preferred embodiments for understanding the present invention will be described. However, each of the embodiments described below is described by way of example, and not only can they be appropriately combined and adopted with each other, but also for the plurality of components described in each embodiment, they can be recognized and adopted independently as much as possible, and can also be appropriately combined and adopted with any of the components described in other embodiments. As a result, in the present invention, various other embodiments can be realized without being limited to the embodiments described below.

[0008] The first aspect is a laminated structure in which a metal cooling surface component member that is superposed on the object to be cooled and a synthetic resin flow path member are superposed on each other, and a cooling flow path through which a heat medium for cooling flows is formed between the superposed surfaces of the cooling surface component member and the flow path member. The cooling surface component member and the flow path member are adhered to each other by an adhesive layer having elasticity in the outer peripheral region, and at a direct joining portion provided in the central region of the flow path member, they are fixed to each other by direct joining without an adhesive.

[0009] According to the cooling heat exchanger having the structure according to this aspect, since the metal cooling surface component member and the synthetic resin flow path member are adhered to each other by an adhesive layer having elasticity, for example, with respect to temperature changes, the difference in the amount of deformation due to the difference in the linear expansion coefficients between the flow path member and the cooling surface component member is allowed by the elastic deformation of the adhesive layer. Therefore, warping or the like of the cooling heat exchanger due to the difference in the linear expansion coefficients between the flow path member and the cooling surface component member is reduced or even prevented.

[0010] Also, the flow path member and the cooling surface component member are adhered by an adhesive layer in the outer peripheral region of the flow path member, and at a direct joining portion provided in the central region of the flow path member, they are fixed to each other by direct joining without the intervention of an adhesive layer. By providing such a direct joining portion, displacement and separation between the flow path member and the cooling surface component member are prevented, and damage (peeling) of the adhesive layer due to the difference in the linear expansion coefficients between the flow path member and the cooling surface component member is also prevented.

[0011] In particular, since the direct joining portion for positioning the flow path member and the cooling surface component member with respect to each other is arranged in the central region of the flow path member, the distance from the direct joining portion to the outer peripheral end of the flow path member becomes relatively small over the entire circumference. Since the difference in the amount of deformation based on the difference in the linear expansion coefficients between the flow path member and the cooling surface component member increases as the distance from the direct joining portion increases, even at the outer peripheral end of the flow path member where the distance from the direct joining portion is the longest, the difference in the amount of deformation based on the difference in the linear expansion coefficients between the flow path member and the cooling surface component member is suppressed.

[0012] In the heat exchanger for cooling according to this aspect, since the difference in the linear expansion coefficients of the flow path member and the cooling surface constituting member is allowed, in the selection of the synthetic resin material for the flow path member and the metal material for the cooling surface constituting member, the linear expansion coefficient is less likely to be a problem, and the forming materials for the flow path member and the cooling surface constituting member can be selected with a high degree of freedom.

[0013] A second aspect is the heat exchanger for cooling described in the first aspect, wherein an adhesive surface is provided at an adhesion portion of the flow path member with the cooling surface constituting member, on which an adhesive is applied to form an adhesive layer, and a position defining portion that protrudes toward the cooling surface constituting member side from the adhesive surface and defines the thickness of the adhesive layer is provided around the adhesive surface.

[0014] According to the heat exchanger for cooling having the structure according to this aspect, since the relative position in the overlapping direction of the flow path member and the cooling surface constituting member is defined by the contact between the cooling surface constituting member and the position defining portion, the thickness of the adhesive layer formed between the overlapping surfaces of the flow path member and the cooling surface constituting member is set accurately. As a result, the allowable amount of deformation based on the difference in the linear expansion coefficients of the flow path member and the cooling surface constituting member due to the elasticity of the adhesive layer is set accurately, and warping of the heat exchanger for cooling due to temperature change, damage or peeling of the adhesive layer, etc. are more stably prevented.

[0015] In particular, since the position defining portion is provided around the adhesive surface to which the adhesive is applied, the thickness of the adhesive layer is set more accurately than in the case where it is provided at a position far from the adhesive surface.

[0016] A third aspect is the heat exchanger for cooling described in the second aspect, wherein an adhesive escape portion that allows the adhesive constituting the adhesive layer to overflow is provided between the adhesive surface and the position defining portion, between the overlapping surfaces of the flow path member and the cooling surface constituting member.

[0017] According to the cooling heat exchanger structured according to this aspect, for example, when forming an adhesive layer with a predetermined thickness between the adhesive surface and the opposing surface of the cooling surface constituent member by making the thickness of the adhesive for the adhesive surface thicker than the distance between the opposing surfaces of the adhesive surface defined by the position defining portion and the cooling surface constituent member, an adhesive escape portion is provided that allows the excess adhesive to protrude from the adhesive surface, thereby preventing problems such as the protruding adhesive leaking into the cooling flow path.

[0018] The adhesive escape portion is preferably formed in a concave shape having a bottom surface that is farther from the cooling surface constituent member than the adhesive surface. This makes it easier to distinguish between the adhesive surface and the adhesive escape portion, facilitates securing the volume of the adhesive escape portion, and makes it difficult for the adhesive protruding from the adhesive surface to overflow from the adhesive escape portion.

[0019] A fourth aspect is the cooling heat exchanger described in the second or third aspect, wherein the adhesive escape portion is continuously provided around the entire circumference of the adhesive surface, and the position defining portion is continuously provided around the entire circumference of the adhesive escape portion.

[0020] According to the cooling heat exchanger structured according to this aspect, since the adhesive escape portion is provided so as to surround the entire circumference of the adhesive surface, the protrusion of the adhesive from the adhesive surface to the outside is allowed in any direction. Further, since the position defining portion is provided so as to surround the entire circumference of the adhesive escape portion, leakage of the adhesive from the adhesive escape portion to the outer periphery is prevented by the position defining portion.

[0021] In addition, since the position defining portion is provided continuously around the circumference of the adhesive surface, the thickness of the adhesive layer formed between the opposing surfaces of the adhesive surface and the cooling surface constituent member can be set more accurately.

[0022] A fifth aspect is the cooling heat exchanger described in any one of the first to fourth aspects, wherein a plurality of the flow path members are superposed on one of the cooling surface constituent members, and the direct joining portions are respectively provided in the central regions of the respective flow path members.

[0023] According to the cooling heat exchanger structured according to this aspect, each flow path member can be miniaturized, and the difference in the amount of deformation between each flow path member and the cooling surface constituent member due to the difference in the linear expansion coefficient with respect to temperature change can be suppressed. In particular, since the direct bonding portions are respectively provided in the central regions of the flow path members that can be made small, the distances from the direct bonding portions to the outer peripheral ends in the respective flow path members can be shortened respectively. Therefore, warping of the cooling heat exchanger, damage to the adhesive layer, etc. can be more effectively prevented.

[0024] By attaching a plurality of flow path members to one cooling surface constituent member, while achieving miniaturization of each flow path member, a cooling heat exchanger of sufficient size can be integrally obtained.

[0025] The sixth aspect is the cooling heat exchanger according to any one of the first to fifth aspects, in which one of the flow path members is superposed on one of the cooling surface constituent members.

[0026] According to the cooling heat exchanger structured according to this aspect, it is possible to configure with a small number of parts by using one flow path member and one cooling surface constituent member. Moreover, even if the flow path member and the cooling surface constituent member have large areas respectively, problems such as warping of the cooling heat exchanger due to the difference in the linear expansion coefficient between the flow path member and the cooling surface constituent member and peeling between the flow path member and the cooling surface constituent member can be reduced.

[0027] The seventh aspect is the cooling heat exchanger according to any one of the first to sixth aspects, in which the direct bonding portion is provided only at one location in the center of the flow path member.

[0028] According to the cooling heat exchanger structured according to this aspect, the structure can be simplified as compared with the case where the central region is directly joined at a plurality of locations. Moreover, when directly joining portions are provided at a plurality of locations, there is a possibility that the difference in the amount of deformation between the flow path member and the cooling surface member due to the difference in the linear expansion rate between these plurality of directly joining portions may not be allowed. However, if the directly joining portion is provided only at one central location, the difference in the amount of deformation is allowed by the adhesive layer over the entire outer peripheral side of the directly joining portion.

Effects of the Invention

[0029] According to the present invention, it is possible to allow the difference in the amount of deformation caused by the difference in the linear expansion rate between the metal cooling surface member that is superposed on the object to be cooled and the synthetic resin flow path member that is superposed on and fixed to the cooling surface member.

Brief Description of the Drawings

[0030]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Modes for Carrying Out the Invention

[0031] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0032] Figs. 1 to 4 show a heat exchanger 10 for cooling as a first embodiment of the present invention. As shown in Fig. 5, the heat exchanger 10 for cooling has a laminated structure in which a metal plate 12 as a cooling surface component and a resin plate 14 as a flow path component are overlapped and fixed to each other. In the following description, in principle, the vertical direction refers to the left - right direction in Fig. 3 which is the overlapping direction of the metal plate 12 and the resin plate 14, the front - rear direction refers to the up - down direction in Fig. 2, and the left - right direction refers to the left - right direction in Fig. 2.

[0033] The metal plate 12 is in the shape of a rectangular plate that is substantially square in top view. The metal plate 12 is preferably formed of a metal material with high thermal conductivity, for example, formed of aluminum, copper, stainless steel, or their alloys.

[0034] A plurality of perforations 16 are formed in the metal plate 12. The perforations 16 have a substantially oval hole cross - sectional shape in which the left - right direction is longer than the front - rear direction. In this embodiment, six perforations 16 are arranged in three rows in the front - rear direction and two rows in the left - right direction.

[0035] Insertion holes 18 penetrating the metal plate 12 are formed at the left - right central part of the metal plate 12. A plurality of insertion holes 18 are formed at intervals in the front - rear direction. The insertion holes 18 are located at the front - rear center between adjacent perforations 16, 16 in the front - rear direction.

[0036] A plurality of through - holes (not shown) are formed at both left - right end portions of the metal plate 12, and port members 20 are attached to each through - hole. The port member 20 has a substantially cylindrical shape extending in the vertical direction as a whole, and a flange - like portion 22 protruding to the outer periphery is integrally provided at the lower end portion.

[0037] In the upper and lower middle part of the port member 20, a retaining projection 24 protruding to the outer periphery is formed. The retaining projection 24 has a smaller protruding dimension to the outer periphery compared to the flange-like portion 22 and is substantially semi-circular in the longitudinal section. The retaining projection 24 can be inserted into a tube or the like of an external flow path described later, and has a function of making it difficult for a tube or the like of an external flow path (not shown) connected to the port member 20 in an externally inserted state to come off.

[0038] The port member 20 is overlapped on the upper surface of the metal plate 12 at the opening peripheral edge of the through hole of the metal plate 12 and is fixed to the metal plate 12 by means such as adhesion or welding. In the present embodiment, since the flange-like portion 22 is provided at the lower end portion of the port member 20, the overlapping area with respect to the upper surface of the metal plate 12 is increased, and it is easy to ensure the fixing strength between the metal plate 12 and the port member 20. The inner hole of the port member 20 is positioned with respect to the through hole of the metal plate 12 and communicates with the space below the metal plate 12.

[0039] The resin plate 14 is in the shape of a rectangular plate that is rectangular in a top view in which the left-right direction is longer than the front-rear direction. As shown in FIG. 2, the resin plate 14 has a width dimension in the left-right direction that is substantially the same as or slightly smaller than that of the metal plate 12, and a length dimension in the front-rear direction that is smaller than that of the metal plate 12. The front-rear length dimension of the resin plate 14 is 1 / 4 or less of the front-rear length dimension of the metal plate 12 and is substantially the same as the separation distance between the adjacent knockout holes 16, 16 in the front-rear direction of the metal plate 12.

[0040] The resin plate 14 is made of a hard synthetic resin, and preferably a thermoplastic synthetic resin material is adopted. As the forming material of the resin plate 14, for example, polyamide, polyester, fluororesin, polyolefin, etc. can be preferably adopted. The resin plate 14 can also be formed of a fiber-reinforced synthetic resin reinforced with glass fiber, carbon fiber, or the like.

[0041] As shown in Fig. 5, the resin plate 14 has a recess 26 that opens on the upper surface. In other words, the resin plate 14 has a substantially rectangular annular outer peripheral adhesive portion 28 whose outer peripheral end portion protrudes upward. The outer peripheral adhesive portion 28 extends in the circumferential direction with a predetermined width. As shown in Fig. 3, the outer peripheral adhesive portion 28 includes a planar adhesive surface 30 that extends substantially orthogonally to the vertical direction in the middle portion in the width direction, a relief groove 32 as an adhesive relief portion that opens upward on the inner peripheral side of the adhesive surface 30, and position defining portions 34a and 34b provided on the outer peripheral side of the adhesive surface 30 and the inner peripheral side of the relief groove 32. The adhesive surface 30, the relief groove 32, and the position defining portions 34a and 34b in the outer peripheral adhesive portion 28 are all annular and continuous over the entire circumference.

[0042] The resin plate 14 is provided with a plurality of inner peripheral adhesive portions 36 that protrude upward from the bottom surface of the recess 26. As shown in Fig. 3, the inner peripheral adhesive portion 36 is a ridge that extends linearly in the left - right direction. In a top view, the inner peripheral adhesive portion 36 has a substantially rectangular shape with a long side whose middle portion in the left - right direction extends linearly in the left - right direction, and both left and right end portions are substantially semi - circular in a top view, and is substantially oval - shaped (oval - shaped) and elongated in the left - right direction as a whole.

[0043] The inner peripheral adhesive portion 36 includes an adhesive surface 38 that extends substantially orthogonally to the vertical direction, an annular relief groove 40 as an adhesive relief portion that extends so as to surround the periphery of the adhesive surface 38 over the entire circumference, and an annular position defining portion 42 that extends so as to surround the periphery of the relief groove 40 over the entire circumference.

[0044] The bottom surface of the relief groove 40 is located below the adhesive surface 38. Therefore, in the inner peripheral adhesive portion 36, the portion constituting the adhesive surface 38 protrudes upward with respect to the portion where the relief groove 40 is formed. Also, the upper surface of the position defining portion 42 is located above the bottom surface of the relief groove 40 and above the adhesive surface 38. The vertical positional difference d between the adhesive surface 38 and the upper surface of the position defining portion 42 is set to the designed thickness dimension of the adhesive layer 54 described later.

[0045] In the resin plate 14, four inner peripheral adhesive portions 36 are arranged side by side in a state of being spaced apart from each other in the front-rear direction. Further, the inner peripheral adhesive portion 36a located at the outer end in the front-rear direction is longer in the left-right direction than the inner peripheral adhesive portion 36b located in the middle in the front-rear direction. The inner peripheral adhesive portions 36b located in the middle in the front-rear direction are arranged in two rows in the front-rear direction and two rows in the left-right direction. In the concave portion 26, between the inner peripheral adhesive portion 36a and the outer peripheral adhesive portion 28, between the inner peripheral adhesive portion 36a and the inner peripheral adhesive portion 36b, and between the inner peripheral adhesive portion 36b and the inner peripheral adhesive portion 36b, they are each formed in a groove shape extending in the left-right direction.

[0046] A central joint portion 44 that constitutes a direct joint portion is provided between the inner peripheral adhesive portions 36b, 36b located on the left side and the inner peripheral adhesive portions 36b, 36b located on the right side. The central joint portion 44 is integrally provided on the resin plate 14 and protrudes upward from the bottom surface of the concave portion 26. The central joint portion 44 is formed in a cylindrical shape and constitutes an insertion hole 46 through which a central hole penetrates the resin plate 14.

[0047] On the outer peripheral side of the insertion hole 46 in the central joint portion 44, similar to the inner peripheral adhesive portion 36, there are an annular adhesive surface 48, a relief groove 50a as an adhesive relief portion extending along the inner peripheral side along the adhesive surface 48, a relief groove 50b as an adhesive relief portion extending along the outer peripheral side along the adhesive surface 48, a position defining portion 52a extending along the inner peripheral side along the relief groove 50a, and a position defining portion 52b extending along the outer peripheral side along the relief groove 50b. In the central joint portion 44, the relief grooves 50a and 50b are provided so as to surround the inner and outer peripheries of the adhesive surface 48 over the entire circumference. Also, in the central joint portion 44, the position defining portion 52a is annularly provided along the inner peripheral side so as to be continuous over the entire length of the relief groove 50a, and the position defining portion 52b is annularly provided along the outer peripheral side so as to be continuous over the entire length of the relief groove 50b. Note that the adhesive surface 48, the relief grooves 50a and 50b, and the position defining portions 52a and 52b are all annular. Also, the relief groove 50 of the central joint portion 44 is narrower than the relief groove 40 of the inner peripheral adhesive portion 36. Further, the position defining portion 52 of the central joint portion 44 is narrower than the position defining portion 42 of the inner peripheral adhesive portion 36. However, the relief groove 50 of the central joint portion 44 and the relief groove 40 of the inner peripheral adhesive portion 36 may have the same width as each other, or the relief groove 50 may be wider than the relief groove 40. Similarly, the position defining portion 52 of the central joint portion 44 and the position defining portion 42 of the inner peripheral adhesive portion 36 may have the same width as each other, or the position defining portion 52 may be wider than the position defining portion 42.

[0048] The bottom surfaces of the relief grooves 50a and 50b are located below the adhesive surface 48. Therefore, in the central joint portion 44, the portion constituting the adhesive surface 48 protrudes upward with respect to the formed portions of the relief grooves 50a and 50b. Also, the upper surfaces of the position defining portions 52a and 52b are located above the bottom surfaces of the relief grooves 50a and 50b and above the adhesive surface 48. The vertical positional difference d between the adhesive surface 48 and the upper surfaces of the position defining portions 52 is set to the thickness dimension of the adhesive layer 54 described later.

[0049] A metal plate 12 is superposed on a resin plate 14 from above. The metal plate 12 is superposed in a contacting state with respect to the position defining portions 34, 42, 52 of the resin plate 14. Thereby, the relative position in the superposing direction between the resin plate 14 and the metal plate 12 is defined by the position defining portions 34, 42, 52.

[0050] In a state where the resin plate 14 and the metal plate 12 are mutually positioned by the position defining portions 34, 42, 52, the bonding surfaces 30, 38, 48 face downward and are spaced apart from the metal plate 12. Further, the bottom surfaces of the relief grooves 32, 40, 50 are spaced downward from the metal plate 12, and the spacing distance is made larger than the spacing distance between the metal plate 12 and the bonding surfaces 30, 38, 48.

[0051] Adhesive layers 54 are respectively formed between the facing surfaces of the bonding surfaces 30, 38, 48 and the metal plate 12, and the outer peripheral region of the resin plate 14 is adhered to the metal plate 12 by the adhesive layers 54. The adhesive layer 54 is formed by the adhesive applied to the bonding surfaces 30, 38, 48 being solidified in a layer form between the bonding surfaces 30, 38, 48 and the lower surface of the metal plate 12 by the superposition of the metal plate 12 on the resin plate 14. The adhesive layer 54 has elasticity and allows relative displacement between the bonding surfaces 30, 38, 48 and the metal plate 12 by elastic deformation while holding the bonding surfaces 30, 38, 48 and the metal plate 12 in a mutually connected state. The longitudinal elastic modulus of the adhesive layer 54 is preferably 500 MPa or less, and more preferably 100 MPa or less.

[0052] As the adhesive for forming the elastic adhesive layer 54, for example, a urethane-based adhesive or an adhesive obtained by mixing an epoxy-based and a silicon-based adhesive can be adopted, and specifically, "EP001K" manufactured by Semedine Co., Ltd. can be mentioned.

[0053] The thickness dimension of the adhesive layer 54 is defined by the vertical position difference d between the bonding surfaces 30, 38, 48 and the upper surfaces of the position defining portions 34, 42, 52. In short, when the metal plate 12 is superposed in contact with the upper surfaces of the position defining portions 34, 42, 52, an adhesive layer 54 with a thickness of d is formed between the bonding surface 30 and the metal plate 12. Thus, based on the relative positional relationship in the vertical direction between the bonding surfaces 30, 38, 48 and the upper surfaces of the position defining portions 34, 42, 52, the thickness dimension of the adhesive layer 54 is stably and accurately set. The thickness d of the adhesive layer 54 is preferably in the range of 0.02 mm to 5 mm, and more preferably in the range of 0.2 mm to 1 mm.

[0054] In order to stably make the thickness of the adhesive layer 54 equal to d, it is necessary to make the thickness of the adhesive applied to the bonding surfaces 30, 38, 48 thicker than d, and then make the adhesive on the bonding surfaces 30, 38, 48 thinner to d by superposing the metal plate 12. Therefore, when the adhesive becomes thinner than the applied state on the bonding surfaces 30, 38, 48, it may protrude from the bonding surfaces 30, 38, 48 to the surroundings. Thus, relief grooves 32, 40, 50 are formed around the bonding surfaces 30, 38, 48, and the adhesive protruding from the bonding surfaces 30, 38, 48 to the inner or outer periphery is accommodated in the relief grooves 32, 40, 50. Thereby, it is possible to prevent the adhesive from protruding to portions other than the inner peripheral bonding portion 36 and the central joining portion 44 in the concave portion 26 (the cooling flow path 58 to be described later), and for example, it is possible to prevent an adverse effect on the flow of the heat medium in the cooling flow path 58 to be described later. In the present embodiment, since the position defining portions 34, 42, 52 are provided so as to surround the relief grooves 32, 40, 50, it is difficult for the adhesive to protrude further outward beyond the relief grooves 32, 40, 50.

[0055] The resin plate 14 and the metal plate 12 bonded together by the adhesive layer 54 are pin - joined at the central portion. That is, a pin 56 is inserted from above into an insertion hole 18 penetrating the metal plate 12 and an insertion hole 46 penetrating the resin plate 14. Then, for example, the shaft portion of the pin 56 protruding downward from the resin plate 14 is compressed axially and crushed to increase its diameter. The metal plate 12 and the resin plate 14 are positioned relative to each other between the tip portion of the shaft portion of the pin 56 with the increased diameter and the head of the pin 56, and the pin 56 is prevented from coming out of the insertion holes 18 and 46. In this way, the central region of the resin plate 14 is directly connected to the metal plate 12 by direct joining with the pin 56 without passing through the adhesive layer 54.

[0056] An annular position - regulating portion 52a is formed around the insertion hole 46 of the resin plate 14, and the position - regulating portion 52a and the metal plate 12 are overlapped in a direct contact state without the intervention of an adhesive. Thereby, the central region of the resin plate 14 is mechanically and directly joined to the metal plate 12 by the pin 56 without passing through the adhesive layer 54. The resin plate 14 and the metal plate 12 are relatively positioned at the direct - joining portion by the pin 56, and relative displacement based on the difference in the linear expansion coefficient described later is prevented. In the present embodiment, the direct - joining portion where the metal plate 12 and the resin plate 14 are directly joined by the pin 56 is provided only at one central location of each resin plate 14.

[0057] The metal plate 12 and the resin plate 14 are adhered by an adhesive layer 54 having elasticity in an outer peripheral region on the outer peripheral side of a central region where a central joint portion 44 is provided in the resin plate 14. Further, the metal plate 12 and the resin plate 14 are directly joined by pins 56 and fixedly connected in a central region where the central joint portion 44 is provided. The central region to be directly joined is constituted by a position defining portion 52a and an insertion hole 46 in the central joint portion 44. It is desirable that the central region has a sufficiently small projected area in the vertical direction compared to the resin plate 14, and the outer diameter of the position defining portion 52a, which is the outer diameter of the central region, is preferably 30 mm or less, and more preferably 10 mm or less.

[0058] In the present embodiment, four resin plates 14, 14, 14, 14 arranged in the front-rear direction are attached to one metal plate 12. Each resin plate 14 is connected to the metal plate 12 by adhesion of the adhesive layer 54 in the outer peripheral region and direct joining by the pins 56 in the central region, respectively.

[0059] By overlapping the metal plate 12 on the upper surface of the resin plate 14, the opening of the recess 26 is covered by the metal plate 12. As a result, a cooling channel 58 through which a heat medium for cooling flows is formed between the metal plate 12 and the resin plate 14. The cooling channel 58 has the inner holes of the port members 20 communicated with both end portions in the left - right direction respectively, and the supply and discharge of the heat medium for cooling are carried out through the port members 20 with respect to an external channel (not shown) connected to the port members 20. A pump, a refrigerator, etc. (not shown) are connected to the external channel, and the heat medium circulates while generating a temperature change due to heat exchange in the circulation path composed of the cooling channel 58 and the external channel. Specifically, for example, the heat medium cooled to a low temperature by a refrigerator is supplied to the cooling channel 58 through one port member 20, and the heat medium that has flowed through the cooling channel 58 while performing heat exchange with a battery pack to be described later and has increased in temperature is discharged to the external channel through the other port member 20. In the present embodiment, a plurality of inner - peripheral adhesion portions 36a, 36b are provided in the recess 26, and a cooling channel 58 extending in the left - right direction is formed by overlapping the metal plate 12 and the resin plate 14. Note that the external channel only needs to be provided with a mechanism for lowering the temperature of the high - temperature heat medium. For example, an air - cooling device or a liquid - cooling device such as a radiator can be provided instead of the refrigerator.

[0060] The heat exchanger 10 for cooling is used, for example, by being mounted on an electrified vehicle such as an electric vehicle or a hybrid vehicle. In the state where the heat exchanger 10 for cooling is mounted on the vehicle, as shown in FIGS. 3 and 4, a battery pack B as a cooling target is overlapped on the portion of the metal plate 12 that is overlapped with the resin plate 14. The battery pack B may be directly overlapped on the metal plate 12, but preferably, it is overlapped on the metal plate 12 without a gap through a heat - conductive gap filler, a heat - conduction sheet, etc. Then, the battery pack B is cooled by the heat exchanger 10 by performing heat exchange through the metal plate 12 with the heat medium flowing through the cooling channel 58.

[0061] Incidentally, the cooling heat exchanger 10 mounted on the vehicle may be used in a high-temperature atmosphere depending on the usage environment of the vehicle or the like. In such a case, in the cooling heat exchanger 10, a difference in the amount of deformation due to the difference in the linear expansion coefficient occurs between the metal plate 12 made of metal and the resin plate 14 made of synthetic resin. In this regard, in the cooling heat exchanger 10, the metal plate 12 and the resin plate 14 are adhered by an adhesive layer 54 having elasticity in the outer peripheral region of the resin plate 14, and are directly joined by pins 56 without passing through the adhesive layer 54 in the central region of the resin plate 14. As a result, in the central region of the resin plate 14, the metal plate 12 and the resin plate 14 are positioned relative to each other and the relative displacement is restricted, and in the outer peripheral region of the resin plate 14, the relative displacement is allowed by the elastic deformation of the adhesive layer 54, and particularly the relative displacement in the plane direction due to the difference in the linear expansion coefficient is sufficiently allowed. Therefore, warping or the like of the cooling heat exchanger 10 due to the difference in the linear expansion coefficient between the metal plate 12 and the resin plate 14 connected to each other is prevented, and peeling or the like of the metal plate 12 and the resin plate 14 due to breakage of the adhesive layer 54 is less likely to occur.

[0062] In particular, since the metal plate 12 and the resin plate 14 are directly joined and positioned relative to each other in the central region, the maximum length from the directly joined portion to the outer peripheral end of the resin plate 14 becomes relatively small. Therefore, the difference in the amount of deformation due to the difference in the linear expansion coefficient between the metal plate 12 and the resin plate 14 is suppressed, and warping of the cooling heat exchanger 10, damage to the adhesive layer 54, misalignment between the metal plate 12 and the resin plate 14, etc. are effectively suppressed.

[0063] In the present embodiment, four resin plates 14, 14, 14, 14 are attached to one metal plate 12. As a result, miniaturization of each resin plate 14 is achieved, and the maximum length from the central joint portion 44 provided in the central region of the resin plate 14 to the outer peripheral end of the resin plate 14 is made smaller. Therefore, the difference in the amount of deformation due to the difference in the linear expansion coefficient between the metal plate 12 and the resin plate 14 is more effectively suppressed.

[0064] By the upper surfaces of the position defining portions 34, 42, 52 of the resin plate 14 coming into contact with the metal plate 12, the thickness d of the adhesive layer 54 formed between the bonding surfaces 30, 38, 48 and the metal plate 12 is accurately set. Thereby, the stabilization of the relative displacement amount between the metal plate 12 and the resin plate 14 allowed by the elasticity of the adhesive layer 54 is achieved, and defects such as warping of the heat exchanger 10 for cooling due to the difference in the linear expansion coefficients of the metal plate 12 and the resin plate 14 are more effectively prevented.

[0065] The longitudinal elastic modulus of the adhesive layer 54 is preferably set to 500 MPa or less, and more preferably 100 MPa or less. Thereby, the relative displacement due to the difference in the linear expansion coefficients between the metal plate 12 and the resin plate 14 due to the elastic deformation of the adhesive layer 54 is sufficiently allowed, and warping of the heat exchanger 10 for cooling and damage to the adhesive layer 54 are avoided.

[0066] The outer diameter dimension of the position defining portion 52a constituting the central region in the narrow sense directly joined by the pins 56 is preferably 30 mm or less, and more preferably 10 mm or less. In this way, by sufficiently reducing the area ratio of the central region in the resin plate 14, the deformation restraint region in the resin plate 14 becomes narrow. As a result, a large area of the outer peripheral region allowing relative displacement with respect to the metal plate 12 is ensured, and warping of the heat exchanger 10 for cooling and damage to the adhesive layer 54 due to the difference in the linear expansion coefficients between the metal plate 12 and the resin plate 14 are prevented.

[0067] FIG. 6 shows a heat exchanger 60 for cooling as a second embodiment of the present invention. As shown in FIG. 7, the heat exchanger 60 for cooling has a structure in which a metal metal plate 62 as a cooling surface constituting member and a synthetic resin resin plate 14 as a flow path member are superposed on each other in the vertical direction. In the following description, for members and parts that are substantially the same as those in the first embodiment, the description will be omitted by attaching the same reference numerals in the drawings.

[0068] The metal plate 62 has a shorter length in the front-rear direction compared to the metal plate 12 of the first embodiment, and has substantially the same front-rear length dimension as the resin plate 14. Therefore, the metal plate 62 is rectangular with a long left-right direction in a top view. The metal plate 62 has an insertion hole 18 formed only at one central location. Through holes (not shown) are formed at diagonal portions of the metal plate 62. Port members 20 are respectively attached to the formation portions of the through holes in the metal plate 62.

[0069] The metal plate 62 is superposed on the resin plate 14 from above, and is adhered with an adhesive having elasticity in the outer peripheral region and is directly joined without passing through the adhesive layer by the pin 56 inserted into the insertion hole 18 in the central region, similar to the first embodiment. In this embodiment, one resin plate 14 is superposed and attached to one metal plate 62.

[0070] As shown in this embodiment, it is also possible to configure the cooling heat exchanger 60 with one metal plate 62 and one resin plate 14. In this case, by making the metal plate 62 and the resin plate 14 relatively small, warping of the cooling heat exchanger 60 due to the difference in the linear expansion coefficient, peeling of the adhesive, etc. are prevented. In addition, instead of the four resin plates 14, 14, 14, 14, one large resin plate is superposed on the large metal plate (12) as shown in the first embodiment, and it is also possible to configure a large cooling heat exchanger with a small number of parts using one metal plate and one resin plate.

[0071] As described above in detail about the embodiments of the present invention, the present invention is not limited by its specific description. For example, the direct joining portion may be provided in the central region on the inner peripheral side rather than the outer peripheral region where the adhesive layer is provided in the synthetic resin-made flow path member, and it is also possible to provide a plurality of direct joining portions in the central region.

[0072] In the first and second embodiments, pin joining was exemplified as the direct joining structure of the direct joining portion. However, the direct joining structure of the direct joining portion is not limited to pin joining. Specifically, for example, a joining structure using bolts 72 and nuts 74 can also be adopted as in the case of the heat exchanger 70 for cooling shown in FIG. 8. Further, for example, by melting the overlapping surface with the cooling surface constituent member in a resin-made flow path member by laser, frictional heat, etc., and welding the flow path member and the cooling surface constituent member, a direct joining structure can also be constituted.

[0073] The adhesive escape portion is not limited to the groove shape as shown in the first and second embodiments, and any structure may be used as long as it is separated from the cooling surface constituent member and forms an accommodation region for the adhesive between the cooling surface constituent member. The adhesive escape portion may be provided, for example, so as to extend outside the adhesive surface on the same plane as the adhesive surface, or may be constituted by a surface closer to the cooling surface constituent member than the adhesive surface.

[0074] The shape of the cooling flow path is not limited to the linearly extending one shown in the above embodiment, and may be, for example, a spiral shape, a planar double spiral shape, a meandering shape, or the like. Further, projections or the like protruding into the cooling flow path may be provided so that the heat medium flowing through the cooling flow path is easily agitated.

[0075] The shapes of the flow path member and the cooling surface constituent member in plan view are not particularly limited, and may be various polygons, circles, etc. in addition to rectangles and squares. Further, the sizes of the flow path member and the cooling surface constituent member are appropriately set according to, for example, the size of the object to be cooled.

[0076] The object to be cooled is not limited to the battery pack B exemplified in the first embodiment, and may be, for example, a control device including an electronic circuit or the like as a heat generating body.

Explanation of Reference Numerals

[0077] 10 Heat exchanger for cooling (first embodiment) 12 Metal plate (cooling surface constituent member) 14 Resin plate (flow path member) 16 Meat extraction hole 18 Insertion hole 20 Port member 22 Flange-shaped part 24 Retaining projection 26 Recess 28 Outer peripheral adhesive part 30 Adhesive surface 32 Relief groove (adhesive relief part) 34 Position regulating part 34a Position regulating part 34b Position regulating part 36 Inner peripheral adhesive part 36a Inner peripheral adhesive part 36b Inner peripheral adhesive part 38 Adhesive surface 40 Relief groove (adhesive relief part) 42 Position regulating part 44 Central joint part (direct joint part) 46 Insertion hole 48 Adhesive surface 50 Relief groove (adhesive relief part) 50a Relief groove (adhesive relief part) 50b Relief groove (adhesive relief part) 52 Position regulating part 52a Position regulating part 52b Position regulating part 54 Adhesive layer 56 Pin 58 Cooling flow path 60 Cooling heat exchanger (second embodiment) 62 Metal plate (cooling surface constituent member) 70 Cooling heat exchanger (another embodiment) 72 Bolt 74 Nut B Battery pack (object to be cooled)

Claims

1. A heat exchanger for cooling, having a laminated structure in which a metal cooling surface component and a synthetic resin flow path component, which are superposed on an object to be cooled, are superposed on each other, and a cooling flow path through which a heat transfer medium for cooling flows is formed between the superposed surfaces of the cooling surface component and the flow path component. The heat exchanger for cooling, wherein the cooling surface component and the flow path component are adhered to each other by an adhesive layer having elasticity in the outer peripheral region, and are fixed to each other by direct joining without an adhesive at a direct joining portion provided in the central region of the flow path component.

2. The heat exchanger for cooling according to claim 1, wherein an adhesive surface on which an adhesive is applied to form the adhesive layer is provided at an adhered portion of the flow path component with the cooling surface component, and a position defining portion that protrudes toward the cooling surface component side from the adhesive surface and defines the thickness of the adhesive layer is provided around the adhesive surface.

3. The heat exchanger for cooling according to claim 2, wherein an adhesive escape portion that allows the adhesive of the adhesive layer to overflow is provided between the adhesive surface and the position defining portion, between the superposed surfaces of the flow path component and the cooling surface component.

4. The heat exchanger for cooling according to claim 2 or 3, wherein the adhesive escape portion is continuously provided over the entire circumference around the adhesive surface, and the position defining portion is continuously provided over the entire circumference around the adhesive escape portion.

5. The heat exchanger for cooling according to claim 1 or 2, wherein a plurality of the flow path components are superposed on one of the cooling surface components, and the direct joining portions are respectively provided in the central regions of the flow path components.

6. The heat exchanger for cooling according to claim 1 or 2, wherein one of the flow path components is superposed on one of the cooling surface components.

7. The heat exchanger for cooling according to claim 1 or 2, wherein the direct joining portion is provided only at one location in the center of the flow path component.

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