Cooling heat exchanger

Abstract

Provided is a novel cooling heat exchanger which is obtained by combining a metal member and a synthetic resin member, the cooling heat exchanger being capable of preventing distortion of a metal plate, for example, even in a high temperature environment, the distortion being associated with deformation of a resin member.　Disclosed is a cooling heat exchanger 10 in which a metal plate 14, which is to be superposed on an object 12 to be cooled, and a resin member 18, which is provided with a recessed groove 16, are superposed on and fixed to each other, and a cooling flow path 22, in which a heat medium flows, is formed between the metal plate 14 and the resin member 18 by covering an opening 20 of the recessed groove 16 with the metal plate 14. The metal plate 14 is provided with a bead part 50 that is opened to a joining surface 46, which is a surface on the resin member 18 side, and projects to a surface 48 on the reverse side from the joining surface 46.

Description

cooling heat exchanger

[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.

[0002] Conventionally, cooling devices for cooling heat-generating elements such as batteries installed in electric vehicles, hybrid vehicles, etc. have been proposed, and such cooling devices are disclosed, for example, in Japanese Patent Laid-Open No. 2020-88108 (Patent Document 1).

[0003] The cooling device described in Patent Document 1 comprises a metal cooling panel that is placed over the heat generating element to be cooled, and a resin flow path for the flow of refrigerant. The opening of a groove provided in the resin flow path is covered by the metal cooling panel, thereby forming a cooling flow path for the flow of refrigerant.

[0004] Japanese Patent Application Laid-Open No. 2020-88108

[0005] However, the difference in linear expansion coefficient between metal and synthetic resin components is relatively large, and when heat is applied to both components, the synthetic resin component is more likely to bulge than the metal component. In particular, when a metal cooling panel is made of, for example, a thin aluminum plate for the purpose of reducing weight and cost, it is susceptible to the influence of the bulging deformation of the synthetic resin component. For example, when a heating element generates heat or the vehicle is exposed to a high-temperature environment, the bulging deformation of the synthetic resin component and the metal cooling panel may become distorted, which may result in refrigerant leakage from the cooling device.

[0006] The present invention has been made against the background of the above-mentioned circumstances, and its problem to be solved is to provide a novel cooling heat exchanger that combines metal members and synthetic resin members and that can prevent distortion of the metal plates due to deformation of the resin members, even in high-temperature environments, for example.

[0007] The following describes preferred embodiments for understanding the present invention, but the embodiments described below are merely examples and may be appropriately combined with one another. Multiple components described in each embodiment may be recognized and employed independently to the greatest extent possible, and may also be appropriately combined with any of the components described in other embodiments. Accordingly, the present invention is not limited to the embodiments described below, and various other embodiments may be realized.

[0008] The first aspect is a cooling heat exchanger in which a metal plate that is placed on top of an object to be cooled and a resin member that has a groove are placed on top of each other and fixed together, and the opening of the groove is covered by the metal plate, thereby forming a cooling flow path through which a heat transfer medium flows between the metal plate and the resin member, and the metal plate is provided with a bead portion that opens at the joining surface, which is the surface on the resin member side, and protrudes from the surface opposite the joining surface.

[0009] According to this aspect, the bead portion is provided on the metal plate, thereby reinforcing the metal plate and preventing distortion of the metal plate due to deformation of the resin member caused by temperature changes, such as from room temperature to a high-temperature environment. Furthermore, the bead portion is provided on the surface of the metal plate on which the object to be cooled is placed, thereby increasing the surface area of ​​the surface on which the object to be cooled is placed, thereby improving heat exchange (cooling) efficiency. In particular, the bead portion according to this aspect can exert special effects in addition to the reinforcing effect of the metal plate, for example, when combined with the second or third aspect described below.

[0010] In a second aspect, in the cooling heat exchanger according to the first aspect, the bead portion is provided at a position on the metal plate that does not form the cooling flow path, and an adhesive layer is provided between the overlapping surfaces of the metal plate and the resin member, so that the metal plate and the resin member are joined by the adhesive, and the bead portion is provided at the portion of the metal plate that is joined to the resin member.

[0011] According to this aspect, the bead portion is provided in a position in the metal plate that does not form a cooling flow path, so the bead portion does not obstruct the flow of the heat transfer medium (refrigerant) through the cooling flow path, and both the cooling effect of the refrigerant flow and the reinforcing effect of the bead portion can be achieved. In particular, the bead portion of the metal plate is provided at the adhesive joint between the metal plate and the resin member, so that the amount of adhesive can be increased by filling the inside of the bead portion, thereby improving the bonding strength between the metal plate and the resin member. This improved bonding strength between the metal plate and the resin member suppresses expansion and deformation of the resin member in high-temperature environments, and therefore also suppresses distortion of the metal plate.

[0012] In a third aspect, in the cooling heat exchanger according to the first or second aspect, the bead portion is provided at a position on the metal plate that forms the cooling flow path.

[0013] According to this aspect, the bead portion is provided at a position in the metal plate that defines the cooling flow path. The bead portion is filled with the heat transfer medium (refrigerant) that flows through the cooling flow path, thereby increasing the amount of refrigerant that can be accommodated in the cooling flow path. Furthermore, the bead portion increases the surface area of ​​the metal plate on which the object to be cooled is placed, thereby enabling more efficient heat transfer from the object to be cooled. As a result, the bead portion not only prevents distortion of the metal plate, but also improves heat exchange (cooling) efficiency.

[0014] In a fourth aspect, in the cooling heat exchanger according to the third aspect, the bead portion extends along the extending direction of the cooling flow path.

[0015] According to this aspect, because the bead portions extend along the extension direction of the cooling flow channel, the heat transfer medium (refrigerant) flows more smoothly within the cooling flow channel, preventing a decrease in heat exchange (cooling) efficiency, compared to when the bead portions are provided intermittently along the extension direction of the cooling flow channel. Also, when the bead portions are provided so as to cross the cooling flow channel, the upstream and downstream sides of the cooling flow channel are connected by the bead portions, which may result in a decrease in heat exchange (cooling) efficiency. However, by providing the bead portions along the extension direction of the cooling flow channel, such a problem can be avoided.

[0016] A fifth aspect is a cooling heat exchanger according to any one of the first to fourth aspects, wherein a heat conduction layer that is deformable in the thickness direction is provided on the surface of the metal plate opposite the joining surface.

[0017] According to this aspect, the thermally conductive layer is deformable in the thickness direction, so that the thermally conductive layer can be deformed to a shape that conforms to the bead portion of the metal plate, and the bead portion and the thermally conductive layer can be in contact with each other with almost no gap. In other words, simply overlapping the bead portion and the object to be cooled may result in a small contact area between the bead portion and the object to be cooled, and efficient heat exchange (cooling) may not occur, but by using the thermally conductive layer as in this aspect, the heat exchange (cooling) efficiency can be improved.

[0018] A sixth aspect is a cooling heat exchanger according to any one of the first to fifth aspects, wherein the bead portion includes a first bead portion and a second bead portion that extend in different directions.

[0019] According to this aspect, for example, the bead portion can be configured to include a first bead portion that extends along the extension direction of the cooling flow path at the position where the cooling flow path is formed, and a second bead portion that extends in a direction perpendicular to the extension direction of the first bead portion at a position where the cooling flow path is not formed, which makes it possible to not only prevent distortion of the metal plate, but also to improve heat exchange (cooling) efficiency and the bonding strength between the metal plate and the resin member.

[0020] According to the present invention, it is possible to provide a cooling heat exchanger that can prevent distortion of a metal plate due to deformation of a resin member even in a high-temperature environment.

[0021] 1 is a perspective view showing a cooling heat exchanger according to an embodiment of the present invention; FIG. 2 is a longitudinal cross-sectional view showing an enlarged view of a main part of the cooling heat exchanger taken along the line II-II of FIG. 1, and is a diagram showing the II-II cross-section in a model; FIG. 3 is a longitudinal cross-sectional view showing an enlarged view of a main part of the cooling heat exchanger taken along the line III-III of FIG. 1, and is a diagram showing the III-III cross-section in a model;

[0022] 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.

[0023] 1 to 4 show a cooling heat exchanger 10 according to one embodiment of the present invention. This cooling heat exchanger 10 is installed in, for example, an electric vehicle or a hybrid vehicle, and is placed over an object to be cooled 12 (shown by a two-dot chain line in FIG. 2 ), such as a battery pack that generates heat in the electric vehicle or hybrid vehicle, to cool the object to be cooled 12. In the following description, the vertical direction generally refers to the vertical direction in FIG. 2 . In addition, in FIGS. 2 and 3 , which show the vertical cross section of the cooling heat exchanger 10, the thickness of each component may be exaggerated for clarity.

[0024] 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 that has a groove 16 are placed on top of each other and fixed together, 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.

[0025] The metal plate 14 is preferably formed from a metal with excellent thermal conductivity, such as copper (including copper alloys) or aluminum (including aluminum alloys). In this embodiment, the metal plate 14 is formed from aluminum. In particular, in this embodiment, as shown in FIG. 5 and other figures, the metal plate 14 is a single, approximately rectangular plate, and its four peripheral sides are formed from 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 in order to reduce weight and costs.

[0026] Furthermore, the metal plate 14 may have through holes 28 (shown by two-dot chain lines in FIGS. 1, 4, and 5) formed therein, penetrating the metal plate 14 in the thickness direction, at positions corresponding to an inlet portion 40 and an outlet portion 42 (described later) in the overlaid 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. 5) among the four corners of the metal plate 14, which has a substantially rectangular plate shape.

[0027] 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 other figures, the resin member 18 has a certain thickness and is in the form of a generally rectangular plate having a planar shape generally 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.

[0028] In this embodiment, the metal plate 14 and the resin member 18 are formed to be approximately the same size when viewed in a plane, and when the metal plate 14 and the resin member 18 are overlapped, a pair of long sides 24, 24 of the metal plate 14 and a pair of long sides 30, 30 of the resin member 18 are overlapped with each other, and a pair of short sides 26, 26 of the metal plate 14 and a pair of short sides 32, 32 of the resin member 18 are overlapped with each other.

[0029] The resin member 18 is formed with a groove 16 that opens upward (having an upper opening 20). The groove 16 has a depth that does not penetrate the resin member 18 in the plate thickness direction (vertical direction) and is a bottomed groove. The shape of the groove 16 is not limited, but the groove 16 of this embodiment has a plurality of parallel passages 34 extending parallel to the long sides 30 of the resin member 18. A partition 36 extending parallel to the long sides 30 of the resin member 18 is provided between adjacent passages 34 in the parallel direction of the passages 34. The passages 34 are connected at both longitudinal ends of each passage 34 by a connecting passage 38 that extends in a direction perpendicular to the longitudinal direction of each passage 34 (parallel to the short sides 32 of the resin member 18).

[0030] 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 portions of the outermost passages 34 in the parallel direction that extend beyond the connecting passages 38 form the inlet section 40 and the outlet section 42. The positions of the inlet section 40 and the outlet section 42 are not limited, but in this embodiment, the inlet section 40 is formed on the left side of the groove 16 in Figure 4, and the outlet section 42 is formed on the right side of the groove 16 in Figure 4.

[0031] Furthermore, the portion of the resin member 18 where the groove 16 is not formed is a frame-like portion 44 that surrounds the groove 16 on all four sides. That is, the frame-like portion 44 includes a pair of portions 44 a, 44 a that are located outside the outermost passages 34 in the direction in which the short side 32 of the resin member 18 extends, and a pair of portions 44 b, 44 b that are located outside the connecting passages 38 in the direction in which the long side 30 of the resin member 18 extends.

[0032] In this embodiment, the widths of the pair of portions 44a, 44a outside each passage 34 (the dimension in the direction in which the short sides 32 of the resin member 18 extend) are approximately equal to each other, and the widths of the pair of portions 44b, 44b outside each connecting passage 38 (the dimension in the direction in which the long sides 30 of the resin member 18 extend) are also approximately equal to each other. In particular, in this embodiment, the width of each portion 44b outside each connecting passage 38 is larger than the width of each portion 44a outside each passage 34. Note that each passage 34 and each partition portion 36 are formed with a relatively long length in the direction in which the long sides 30 of the resin member 18 extend. Therefore, the recessed groove 16 is formed with a shape whose longitudinal direction is the direction in which the long sides 30 of the resin member 18 extend.

[0033] Here, the metal plate 14 is provided with a bead portion 50 that opens to the joining surface 46, which is the surface on the resin member 18 side (i.e., the lower surface), and protrudes to the surface opposite the joining surface 46 (i.e., the upper surface 48). In this embodiment, a plurality of bead portions 50 are provided, and each of the plurality of bead portions 50 includes a first bead portion 50a and a second bead portion 50b that extend in different directions. Therefore, the first bead portion 50a and the second bead portion 50b each have a downward opening portion 52 that opens downward. Although the cross-sectional shapes of the first bead portion 50a and the second bead portion 50b are not limited, in this embodiment, each has a substantially semicircular cross-sectional shape.

[0034] In particular, in this embodiment, the first bead portion 50a extends parallel to the direction in which the long sides 24 of the metal plate 14 extend, and the second bead portion 50b extends parallel to the direction in which the short sides 26 of the metal plate 14 extend. The first bead portion 50a and the second bead portion 50b are formed, for example, by pressing the metal plate 14, and the first bead portion 50a and the second bead portion 50b are each formed with a certain depth dimension (and a certain protruding height dimension from the upper surface 48 of the metal plate 14).

[0035] A plurality of first bead portions 50a are provided, and the first bead portions 50a are arranged in parallel and spaced apart in the direction of extension of the short side 26 in the intermediate portion of the metal plate 14 in the direction of extension of the long side 24. In this embodiment, when the metal plate 14 and the resin member 18 are fixed together, each first bead portion 50a is located at the same position in a plan view as each passage 34 (i.e., between opposing partition portions 36) in the recessed groove 16. Furthermore, each first bead portion 50a is formed with a length dimension approximately equal to that of each passage 34 (and partition portion 36) in the direction of extension of the long side 24 of the metal plate 14, and each first bead portion 50a is formed with a certain size of internal space 54a. Furthermore, the maximum width dimension of each first bead portion 50a is approximately equal to the width dimension of each passage 34.

[0036] A plurality of second bead portions 50b are provided, and pairs of second bead portions 50b, 50b are arranged parallel to each other and spaced apart in the direction of extension of the long side 24 of the metal plate 14. In this embodiment, each second bead portion 50b is located outside the recessed groove 16 in a plan view when the metal plate 14 and the resin member 18 are fixed together. In particular, in this embodiment, each second bead portion 50b is located in the metal plate 14 at portions 44b, 44b outside the connecting passages 38 of the frame-shaped portion 44, corresponding to positions outside the inlet portion 40 and the outlet portion 42, respectively. In other words, each second bead portion 50b is located at both longitudinal ends of the metal plate 14. Each second bead portion 50b is formed to have a certain length in the direction of extension of the short side 26 of the metal plate 14, and each second bead portion 50b is formed with a certain size of internal space 54b.

[0037] The metal plate 14 is placed on the resin member 18 having the above-described structure from above, and the resin member 18 and the metal plate 14 are fixed together. In this embodiment, the resin member 18 and the metal plate 14 are fixed together by adhesive, and an adhesive layer 56 (see FIGS. 2 and 3 ) is formed over substantially the entire area between the overlapping surfaces of the metal plate 14 and the resin member 18. By joining the metal plate 14 and the resin member 18 via the adhesive layer 56, the opening of the groove 16 (the upper opening 20) is liquid-tightly sealed by the metal plate 14. In particular, in this embodiment, the upper surface of the frame portion 44 of the resin member 18 and the upper surfaces of the partition portions 36 are placed on the metal plate 14, and therefore the adhesive layer 56 is provided between these upper surfaces and the metal plate 14. That is, the adhesive layer 56 is not provided at the positions where the passages 34 and the connecting passages 38 are formed in the resin member 18 and where the first bead portions 50 a are formed in the metal plate 14.

[0038] Here, the passages 34 in the resin member 18 and the first bead portions 50a in the metal plate 14 are formed in corresponding positions, and since the adhesive layer 56 is not provided at the positions where the passages 34 and the first bead portions 50a are formed, when the resin member 18 and the metal plate 14 are fixed together, the internal spaces of the passages 34 and the internal spaces 54a of the first bead portions 50a are overlapped and communicated with each other in the vertical direction, as shown in Fig. 2. As a result, the upper openings 20 of the passages 34 are covered by the first bead portions 50a in the metal plate 14, forming tunnel-like passages. Furthermore, the upper openings 20 of the connecting passages 38 are covered by the metal plate 14, forming tunnel-like passages.

[0039] That is, by covering the upper openings 20 of each passage 34, a plurality of parallel tunnel-shaped passages are formed in the direction of the short side 32 of the resin member 18, and these tunnel-shaped passages are connected to each other by tunnel-shaped passages that are formed by covering the upper openings 20 of each connecting passage 38 and extend in the direction of the short side 32. As a result, the tunnel-shaped passages are interconnected to form the cooling flow passages 22 through which the refrigerant flows. Therefore, the cooling flow passages 22 as a whole extend in the direction of the long side 24 of the metal plate 14, which is the longitudinal direction of the recessed groove 16, and each first bead portion 50a that constitutes the bead portion 50 extends along the extension direction of the cooling flow passages 22.

[0040] Furthermore, the frame-shaped portion 44 located on the outer periphery of the recessed groove 16 in the resin member 18 is fixed to the metal plate 14 via an adhesive layer 56. Here, second bead portions 50b are provided on the metal plate 14 at positions corresponding to the pair of portions 44b, 44b of the frame-shaped portion 44 that are outside the connecting passages 38, and as shown in Fig. 3, the lower openings 52 of the second bead portions 50b are covered by the resin member 18 via the adhesive layer 56. As a result, the internal space 54b of each second bead portion 50b is formed as a sealed space, and the internal space 54b of each second bead portion 50b is filled with the adhesive that constitutes the adhesive layer 56.

[0041] In short, in this embodiment, each of the first bead portions 50a constituting the bead portion 50 is provided at a position on the metal plate 14 that defines the cooling flow path 22. On the other hand, each of the second bead portions 50b constituting the bead portion 50 is provided at a position on the metal plate 14 that does not define the cooling flow path 22, and each of the second bead portions 50b is provided at a portion of the metal plate 14 that is joined to the resin member 18.

[0042] As described above, the adhesive layer 56 is provided over substantially the entire surface between the overlapping surfaces of the metal plate 14 and the resin member 18, and is formed as a substantially rectangular region in a plan view. Before the metal plate 14 and the resin member 18 are fixed to each other, the adhesive layer 56 may be provided on the lower surface (joining surface 46) of the metal plate 14 and / or the upper surface of the resin member 18. The method for providing the adhesive layer 56 on the lower surface of the metal plate 14 and / or the upper surface of the resin member 18 is not limited, and any known method may be used, such as application with a brush or spraying, or immersion in a material for the adhesive layer 56 before it hardens.

[0043] 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 flow path 22 is communicated with the external space through these through holes 28. In this case, the inlet portion 40 and the through holes 28 provided at the positions corresponding to the inlet portion 40 form an inlet port 58 for allowing the refrigerant to flow into the cooling flow path 22 from the outside, and the outlet portion 42 and the through holes 28 provided at the positions corresponding to the outlet portion 42 form an outlet port 60 for allowing the refrigerant to flow out of the cooling flow path 22 to the outside.

[0044] The refrigerant flowing through the cooling flow path 22 is not limited, but may be chiller water used in chillers (cooling water circulation systems) conventionally installed in vehicles, and specifically may be water, alcohol (methanol, ethanol, etc.), glycol, etc. The source of the refrigerant flowing through the cooling flow path 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 using a chiller including a pump as the refrigerant source, the refrigerant can be caused to flow through the cooling flow path 22.

[0045] In the thus configured cooling heat exchanger 10, a heat-generating body (cooling target 12), such as a battery pack, that generates heat when current is applied is placed on the surface (top surface 48) of the metal plate 14 opposite the surface on which the resin member 18 is superimposed. In the cooling heat exchanger 10 of this embodiment, as shown in Fig. 2, a thermally conductive layer 62 that is deformable in the thickness direction is provided on the top surface 48, which is the surface of the metal plate 14 opposite the joining surface 46.

[0046] The thermally conductive layer 62 is, for example, sheet-shaped and made of a synthetic resin with a thermal conductivity greater than that of air. Specifically, silicone-based resins, non-silicone acrylic resins, ceramic resins, and more specifically, thermally conductive silicone rubber are examples of such resins. The thermally conductive layer 62 does not have to be sheet-shaped before being disposed on the upper surface 48 of the metal plate 14. For example, the thermally conductive layer 62 may be in a gel or grease form that hardens into a sheet upon application of heat or exposure to light (e.g., ultraviolet light). That is, the thermally conductive layer 62 may be made of a known thermally conductive sheet, thermally conductive grease, thermally conductive gap filler, or the like.

[0047] Because the thermally conductive layer 62 is deformable in the thickness direction, the thermally conductive layer 62 deforms along each of the first bead portions 50a protruding upward from the upper surface 48 of the metal plate 14, and is disposed in contact with the upper surface 48 of the metal plate 14 with almost no gap between them. The area where the thermally conductive layer 62 is disposed is not limited, and the thermally conductive layer 62 may be disposed in the same shape and size as the metal plate 14 and the resin member 18 in a plan view, in the area where each of the first bead portions 50a is formed, or in a size smaller than the area where each of the first bead portions 50a is formed. Alternatively, the thermally conductive layer 62 may be disposed in a position outside the grooves 16 in the resin member 18 in a plan view.

[0048] Furthermore, for example, when the through holes 28 are provided in the metal plate 14 to form the inlet 58 and the outlet 60, an inlet tube 64 is connected to the inlet 58 on the upper surface 48 of the metal plate 14, with one end of the inlet tube 64 extending outside the cooling heat exchanger 10 and connected to a refrigerant source (not shown). Furthermore, an outlet tube 66 is connected to the outlet 60, with one end of the outlet tube 66 extending outside the cooling heat exchanger 10 and connected to a refrigerant source (not shown). That is, in this embodiment, a circulation system is configured in the cooling heat exchanger 10, in which the refrigerant flows from the refrigerant source through the inlet tube 64, flows into the cooling flow path 22 from the inlet 58, flows through the cooling flow path 22, and then returns to the refrigerant source through the outlet 60 and the outlet tube 66. Note that these inlet and outlet tubes 64, 66 are provided, for example, at positions on the upper surface 48 of the metal plate 14 away from the cooling target 12.

[0049] In the cooling heat exchanger 10 configured as described above, a heat-generating body (target 12), such as a battery pack, is placed on the metal plate 14. When the target 12 generates heat, the heat generated in the target 12 is transferred to the metal plate 14. The heat transferred to the metal plate 14 is cooled (heat exchanged) by the refrigerant flowing through the cooling channels 22, preventing a temperature rise in the target 12 and the metal plate 14. Meanwhile, the refrigerant that flows into the cooling channels 22 from the inlets 58 is heated as it flows through the cooling channels 22, and flows out of the outlets 60 at a higher temperature than when it flowed in from the inlets 58, and reaches a refrigerant source (not shown). In this refrigerant source, the refrigerant is cooled again and flows into the cooling channels 22 through the inlets 58.

[0050] That is, when the object to be cooled 12 generates heat and the refrigerant flows through each cooling channel 22, the temperature of the refrigerant rises, which in turn raises the temperature of the resin members 18 that constitute each cooling channel 22. Alternatively, the temperature of the cooling heat exchanger 10 rises when the vehicle is exposed to a high-temperature environment. With such temperature changes, the difference in linear expansion coefficients between the metal plate 14, which is a metal member, and the resin member 18, which is a synthetic resin member, is relatively large, resulting in the resin member 18 expanding more than the metal plate 14. As a result, in cooling heat exchangers with conventional structures, there is a risk of distortion of the metal plate due to the expansion and deformation of the resin member. In particular, when the metal plate is thin and plate-shaped to reduce weight and cost, distortion of the metal plate is even more likely to occur in a high-temperature environment.

[0051] In contrast, in the cooling heat exchanger 10 of this embodiment, the metal plate 14 is provided with a bead portion 50 that opens toward the resin member 18 and protrudes from the opposite (upper) surface (top surface 48). By providing the bead portion 50 on the metal plate 14, the reinforcing effect of the bead portion 50 can prevent distortion of the metal plate 14.

[0052] In particular, in this embodiment, the bead portion 50 includes a plurality of first bead portions 50a provided at positions on the metal plate 14 that define the cooling flow passages 22, and a plurality of second bead portions 50b provided at positions that do not define the cooling flow passages 22. The internal space 54a of each first bead portion 50a communicates with the internal space of each passage 34 that defines the groove 16, thereby increasing the volume of the cooling flow passage 22 by the amount of each first bead portion 50a. As a result, not only is the amount of refrigerant flowing through the cooling flow passage 22 increased, but the surface area of ​​the inner surface of the cooling flow passage 22 can also be increased, improving the cooling (heat exchange) efficiency associated with the flow of refrigerant.

[0053] Furthermore, since each of these first bead portions 50a extends parallel to the direction in which the long side 24 of the metal plate 14, which is the extension direction of the cooling flow path 22, the provision of each first bead portion 50a can prevent the flow of refrigerant within the cooling flow path 22 from being obstructed.

[0054] In addition, a thermally conductive layer 62 is provided on the upper surface 48 of the metal plate 14. The thermally conductive layer 62 is deformable in the thickness direction, and deforms to match the shape of each first bead portion 50a protruding upward from the upper surface 48 of the metal plate 14 and the object to be cooled 12. This ensures a large contact area between the thermally conductive layer 62 and the metal plate 14, and a large contact area between the object to be cooled 12 and the thermally conductive layer 62. As a result, heat generated in the object to be cooled 12 can be efficiently transferred to the metal plate 14 via the thermally conductive layer 62, further improving cooling (heat exchange) efficiency.

[0055] On the other hand, because each second bead portion 50b is provided at the joint between the metal plate 14 and the resin member 18, the adhesive constituting the adhesive layer 56 is filled up to the internal space 54b of each second bead portion 50b, thereby increasing the amount of adhesive by the amount of each second bead portion 50b. In particular, the provision of the second bead portions 50b increases the surface area of ​​the inner surface of the metal plate 14 (i.e., the joint surface 46), thereby improving the adhesive strength between the metal plate 14 and the resin member 18 through the adhesive layer 56. Furthermore, by improving the adhesive strength between the metal plate 14 and the resin member 18 in this manner, distortion of the metal plate 14 due to expansion and deformation of the resin member 18 can be suppressed. In particular, in this embodiment, the second bead portions 50b are provided at both ends of the metal plate 14 and the resin member 18 in the longitudinal direction (the direction in which each long side 24, 30 extends), which effectively suppresses deformation of the resin member 18 in the longitudinal direction, thereby suppressing distortion of the metal plate 14.

[0056] Furthermore, by arranging the first bead portion 50a and the second bead portion 50b to extend in different directions, in addition to the effects of improving the cooling (heat exchange) efficiency and adhesive strength as described above, a good reinforcing effect is exerted, for example, when the metal plate 14 extends in multiple directions rather than just one direction, and distortion of the metal plate 14 due to expansion and deformation of the resin member 18 in a high-temperature environment can be more efficiently avoided.

[0057] Although one embodiment of the present invention has been described in detail above, the present invention is not limited in any way by the specific description of the embodiment, 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.

[0058] For example, in the above embodiment, the lower surface of the metal plate 14 and the upper surface of the resin member 18 are substantially the entire overlapping and bonding surfaces. However, the metal plate and the resin member only need to be bonded to each other along at least the entire circumference of the recessed grooves to prevent refrigerant leakage from the cooling channels. For example, a non-bonded area (an area where the metal plate and the resin member are not bonded) may be provided around the outer periphery of the bonding area between the overlapping surfaces of the metal plate and the resin member. In addition to the bead portions provided in the positions where the cooling channels are formed and / or in the bonding areas as in the above embodiment, bead portions may be provided in the positions where the cooling channels are not formed and in the non-bonded areas. The provision of such bead portions reinforces the metal plate and improves the distortion prevention effect. However, the method of bonding the metal plate and the resin member is not limited to bonding, and may be, for example, welding. Even when the metal plate and the resin member are fixed by welding, providing a bead portion in the bonding area may improve the bonding strength between the metal plate and the resin member by, for example, allowing the overlapping surface (top surface) of the resin member to penetrate into the bead portion.

[0059] In the above embodiment, the bead portion 50 includes a plurality of first bead portions 50a and a plurality of second bead portions 50b. However, this is not limited to this. For example, only the first bead portion may be provided, and only one first bead portion may be provided at a position on the metal plate where a cooling flow channel is formed. In such a case, it is preferable that the bead portion extend along the extension direction of the cooling flow channel. Alternatively, only the second bead portion may be provided, and only one second bead portion may be provided at a position on the metal plate where no cooling flow channel is formed and where the metal plate and the resin member are joined. In such a case, the extension direction of the bead portion is not limited, and may be, for example, the extension direction of the cooling flow channel or a direction perpendicular to the extension direction of the cooling flow channel. Note that the first bead portion and the second bead portion are not limited to extending in directions perpendicular to each other, and may intersect at a certain angle. Furthermore, the plurality of first bead portions may be connected to one another by being folded back in the length direction, or the first bead portion and the second bead portion may be provided continuously.

[0060] In the above embodiment, the cross-sectional shape of each of the first bead portions 50 a and each of the second bead portions 50 b is substantially semicircular, but the cross-sectional shape of the bead portions is not limited thereto and may be a polygonal shape such as a triangle or a rectangle, or may be a semi-oval or semi-elliptical shape. The shapes of these first bead portions and second bead portions may differ in the longitudinal direction, and when multiple first bead portions and second bead portions are provided, they may be combined to adopt different shapes.

[0061] In the above embodiment, each of the first bead portions 50 a and each of the second bead portions 50 b extends continuously over a certain length, but the bead portions may be formed intermittently over a certain length. From the viewpoint of improving the flow efficiency of the refrigerant in the cooling flow channel and the adhesive strength of the adhesive, it is preferable that the bead portions be provided continuously over a certain length.

[0062] In the above embodiment, the metal plate 14 is provided with the through holes 28, and the inlet 58 and the outlet 60 open upward, but the present invention is not limited to this. For example, through holes may be provided in the bottom wall of the resin member that forms the inlet and outlet portions, so that the inlet and outlet open downward from the resin member, or through holes may be provided in the peripheral wall that forms the inlet and outlet portions, so that the inlet and outlet open to the side of the resin member.

[0063] In the above embodiment, each groove 16 includes a plurality of parallel passages 34 and connecting passages 38 connecting the passages 34, but the present invention is not limited to this. The openings (upper openings) of the grooves are covered with metal plates to form cooling channels, but the extension direction, length, width, depth, and other aspects of the cooling channels can be set as desired. However, from the viewpoint of cooling efficiency (heat exchange efficiency), it is preferable that the cooling channels be provided over a wide area of ​​the resin member.

[0064] In the above embodiment, the metal plate 14 and the resin member 18 are formed to have substantially the same shape and size in a plan view, but this is not limited to this. The metal plate and the resin member may have different shapes and sizes in a plan view. Furthermore, even if the metal plate and the resin member are formed to have substantially the same shape and size in a plan view, the metal plate and the resin member may be offset from each other, i.e., they may overlap partially rather than entirely in a plan view. In either of the above cases, the cooling flow path is formed by the metal plate covering the opening of the groove provided in the resin member. These overlapping portions are the overlapping surfaces of the two 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.

[0065] In the above embodiment, each first bead portion 50a is formed at a position and with a width corresponding to each passage 34 in a plan view. However, this is not limited to this. For example, the first bead portion and the passage in the groove may be offset from each other so that they overlap partially, rather than entirely, in a plan view. Furthermore, the first bead portion and the passage in the groove may have different widths, for example. One first bead portion may be provided across multiple passages, or multiple first bead portions may be provided on one passage. In such cases, it is preferable to provide the first bead portion so that the upstream and downstream sides of the cooling flow path do not communicate with each other. This can prevent a decrease in cooling efficiency.

[0066] In the above embodiment, the cooling heat exchanger 10 is 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. For example, the heat-generating body to be cooled may be an in-vehicle component other than a battery pack, or may be a component used in a vehicle other than a vehicle. 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 a vehicle other than a vehicle.

[0067] REFERENCE SIGNS LIST 10 Cooling heat exchanger 12 Cooling object 14 Metal plate 16 Groove 18 Resin member 20 Upper opening (opening) 22 Cooling flow path 24 Long side 26 Short side 28 Through hole 30 Long side 32 Short side 34 Passage 36 Partition 38 Connecting passage 40 Inlet portion 42 Outlet portion 44 Frame-shaped portion 44a Portion outside each passage 44b Portion outside each connecting passage 46 Joining surface (surface of metal plate facing resin member) 48 Upper surface (surface opposite to joining surface) 50 Bead portion 50a First bead portion 50b Second bead portion 52 Lower opening 54a, 54b Internal space 56 Adhesive layer 58 Inlet 60 Outlet 62 Heat conduction layer 64 Inlet tube 66 Outlet tube

Claims

1. A cooling heat exchanger 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 with 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 the metal plate has a bead portion that opens on the joining surface, which is the surface facing the resin member, and protrudes onto the surface opposite the joining surface.

2. A cooling heat exchanger as described in claim 1, wherein the bead portion is provided at a position on the metal plate which does not form the cooling flow path, an adhesive layer is provided between the overlapping surfaces of the metal plate and the resin member so that the metal plate and the resin member are joined by the adhesive, and the bead portion is provided at the portion of the metal plate which is joined to the resin member.

3. A cooling heat exchanger according to claim 1 or 2, wherein the bead portion is provided at a position on the metal plate that defines the cooling flow path.

4. A heat exchanger for cooling according to claim 3, wherein said bead portion extends along the extending direction of said cooling flow passage.

5. A heat exchanger for cooling according to any one of claims 1 to 4, wherein a thermally conductive layer capable of deforming in a thickness direction is provided on a surface of said metal plate opposite to said joint surface.

6. A heat exchanger for cooling according to any one of claims 1 to 5, wherein the bead portion comprises a first bead portion and a second bead portion which extend in different directions.

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