Cooling heat exchanger

Abstract

Provided is a cooling heat exchanger having a novel structure, the cooling heat exchanger being capable of stably achieving high cooling efficiency with a simple configuration having a small number of components.　In a cooling heat exchanger 10 for cooling a to-be-cooled object 34, a heat-conducting elastic body 14 provided by mixing a multitude of heat-conductive fillers 24 with an elastic base material 22 is formed in close contact with the surfaces of heat passage members 12 for cooling. The heat-conducting elastic body 14 has formed thereon cooling surfaces 26 that are allowed to be deformed in accordance with the to-be-cooled object 34 and are superposed on the to-be-cooled object 34. The multitude of heat-conductive fillers 24 in the heat-conducting elastic body 14 form heat-conductive paths between the cooling surfaces 26 and the heat passage members 12 for cooling.

Description

cooling heat exchanger

[0001] The present invention relates to a cooling heat exchanger used to cool an object to be cooled, such as a battery pack, in an electrically powered vehicle such as an electric automobile.

[0002] In electrified vehicles such as electric vehicles and hybrid vehicles, the objects to be cooled, such as battery packs and electronic devices, are becoming increasingly smaller and more powerful, generating more heat, making cooling performance increasingly important. To cool battery packs and other components, a cooling heat exchanger with a cooling passage formed between overlapping metal plates has traditionally been used. In this cooling heat exchanger, one plate is overlapped with the object to be cooled, such as a battery pack, and the object is cooled by cooling the plate with a refrigerant flowing through the cooling passage.

[0003] In addition, due to the strong demand for lightweight vehicles in electric vehicles, weight reduction of cooling heat exchangers is also being considered. For example, Japanese Patent Laid-Open Publication No. 2020-088108 (Patent Document 1) proposes that one plate that is overlaid on the object to be cooled and requires high thermal conductivity is made of a metal cooling panel, and the other plate that does not require thermal conductivity is made of a resin flow channel made of a synthetic resin with a lower specific gravity than metal. In Patent Document 1, the resin flow channel is plate-shaped, and the grooves opening on the surface of the resin flow channel are covered with a metal cooling panel to form a cooling passage through which a refrigerant flows.

[0004] Japanese Patent Application Laid-Open No. 2020-088108

[0005] When using the above-described conventional cooling heat exchanger, a thermally conductive layer is provided between the cooling object, such as a battery pack, and the cooling surface that is the surface that overlaps with the cooling object in order to efficiently cool the cooling object. The thermally conductive layer is formed, for example, from an elastically deformable sheet or a viscous gel, and fills gaps caused by minute irregularities on the overlapping surfaces of the cooling surface of the cooling heat exchanger and the cooling object, thereby improving the heat exchange efficiency between the cooling heat exchanger and the cooling object.

[0006] However, because such a thermally conductive layer is provided between the overlapping surfaces of the cooling surface and the cooling object when assembling the cooling heat exchanger and the cooling object, the number of parts increases and the assembly becomes more complicated. In particular, the thermally conductive layer needs to be positioned relative to the overlapping surfaces of the cooling surface and the cooling object, but when the cooling object is overlapped with the cooling surface via the thermally conductive layer, the thermally conductive layer may become misaligned, reducing the effective overlapping area between the cooling surface and the cooling object and reducing the heat exchange efficiency.

[0007] An object of the present invention is to provide a cooling heat exchanger having a novel structure that can stably achieve high cooling efficiency with a simple configuration having a small number of parts.

[0008] Another object of the present invention is to provide a method for manufacturing a cooling heat exchanger having the above-mentioned novel structure.

[0009] 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.

[0010] The first aspect is a cooling heat exchanger for cooling an object to be cooled, in which a heat transfer elastic body made of an elastic base material mixed with a large number of heat conductive fillers is formed in close contact with the surface of a heat passage member for cooling, the heat transfer elastic body is allowed to deform in accordance with the object to be cooled and a cooling surface is formed in the heat transfer elastic body so that it is superimposed on the object to be cooled, and the large number of heat conductive fillers in the heat transfer elastic body form a heat conduction path between the cooling surface and the heat passage member for cooling.

[0011] In a cooling heat exchanger constructed according to this embodiment, the heat path member for cooling and the object to be cooled can be closely attached to each other via the heat transfer elastomer without the need for a separate heat conduction layer between them. Furthermore, the heat transfer elastomer, in which a large number of heat conduction fillers are mixed into the elastic base material, provides a heat conduction path through the large number of heat conduction fillers. Therefore, even when the heat transfer elastomer is interposed between the cooling surface and the heat path member for cooling, it sufficiently allows heat transfer between the cooling surface and the heat path member for cooling. Therefore, effective cooling of the object to be cooled through efficient heat exchange between the heat path member for cooling and the object to be cooled can be achieved with a small number of components.

[0012] Furthermore, because the heat transfer elastic body is formed in close contact with the surface of the heat path member for cooling, when, for example, an object to be cooled is placed on the cooling surface, the heat transfer elastic body does not shift relative to the heat path member for cooling, and the cooling surface is maintained in a position relative to the heat path member for cooling. Therefore, the cooling surface is stably cooled by the heat path member, and stable cooling of the object to be cooled placed on the cooling surface is achieved.

[0013] In a second aspect, in the cooling heat exchanger described in the first aspect, the numerous heat conductive fillers are oriented in a linear pattern extending in the opposing direction between the cooling heat path member and the cooling surface, so that the heat conductive path is formed by the numerous heat conductive fillers in a form extending in the opposing direction between the cooling heat path member and the cooling surface.

[0014] In the cooling heat exchanger constructed according to this aspect, the heat conduction path extending in the opposing direction between the heat path member for cooling and the cooling surface superimposed on the object to be cooled allows efficient heat exchange between the heat path member for cooling and the object to be cooled, thereby effectively cooling the object to be cooled. In particular, the heat conduction path extending in the opposing direction between the heat path member for cooling and the cooling surface allows heat to be transferred from the heat path member for cooling to the cooling surface over a short path, thereby further improving cooling efficiency.

[0015] In a third aspect, in the cooling heat exchanger described in the first or second aspect, the thermally conductive filler is formed of a magnetic material, and a large number of the thermally conductive fillers are oriented in a form that forms a magnetic path in a specific direction inside the heat transfer elastic body.

[0016] In a cooling heat exchanger constructed in accordance with this embodiment, for example, by applying a magnetic field during molding of the heat transfer elastomer, it is possible to orient the heat conductive filler in a specific direction, and a heat conduction path can be formed easily with high thermal conductivity.

[0017] In a fourth aspect, in the cooling heat exchanger described in any one of the first to third aspects, the cooling heat passage member is configured to include a pipe member, and the cooling passage through which the cooling heat medium flows is configured by the inner hole of the pipe member.

[0018] In the cooling heat exchanger constructed according to this aspect, the pipe members are kept cooled by the heat transfer medium flowing through the inner holes of the pipe members, so that the object to be cooled is continuously cooled by heat exchange between the pipe members and the object to be cooled. Furthermore, since the walls of the cooling passages are made of pipe members, leakage of the heat transfer medium from the cooling passages can be prevented.

[0019] A fifth aspect is a cooling heat exchanger according to the fourth aspect, wherein the pipe member is made of a non-magnetic material and the thermally conductive filler is made of a magnetic material.

[0020] In a cooling heat exchanger constructed in accordance with this embodiment, for example, when a magnetic field is applied during molding of a heat transfer elastomer to orient the heat conductive filler in a specific direction, if the pipe member is formed from a non-magnetic material, the pipe member will not disturb the magnetic field by inducing magnetic flux, etc., making it easier to form the desired heat conduction path.

[0021] In a sixth aspect, in the cooling heat exchanger described in the fourth or fifth aspect, the portion of the pipe member that is fixed to the heat transfer elastic body is in the shape of a flat tube that is wide when projected in a direction perpendicular to the cooling surface.

[0022] According to the cooling heat exchanger constructed in accordance with this aspect, the projected area of ​​the pipe member relative to the cooling surface is increased, so that the cooling surface can be cooled more efficiently.

[0023] In a seventh aspect, in the cooling heat exchanger described in any one of the first to sixth aspects, the cooling heat passage member is configured to include a bag body having a cooling passage inside which a cooling heat medium flows.

[0024] In the cooling heat exchanger constructed according to this aspect, the heat path member for cooling is a bag, which makes it easy to manufacture the heat path member. Furthermore, by flowing a heat medium for cooling through the cooling passage formed inside the bag, the bag is maintained in a cooled state, and the object to be cooled is continuously cooled by heat exchange between the bag and the object to be cooled. Furthermore, since the surface of the heat path member for cooling, which is made of a bag, is allowed to deform, the cooling surface that follows the object to be cooled is allowed to deform with a greater degree of freedom, thereby improving the adhesion of the cooling surface to the object to be cooled.

[0025] In an eighth aspect, in the cooling heat exchanger described in any one of the first to seventh aspects, the cooling heat passage member has a structure in which a heat-transferring lid is fixed in a laminated state to the surface of a passage-forming member made of synthetic resin, the passage-forming member has a void that opens to the surface, the opening of the void is covered with the heat-transferring lid to form a cooling passage through which a cooling heat medium flows, and the heat-transferring elastic body is formed in close contact with the surface of the heat-transferring lid.

[0026] According to a cooling heat exchanger constructed in accordance with this embodiment, when a cooling heat passage member in which a cooling passage is formed between the overlapping surfaces of a passage-forming member and a heat-transferring lid is used, a heat-transferring elastomer is formed in close contact with the surface of the heat-transferring lid, and the heat-transferring lid and the object to be cooled are brought into close contact via the heat-transferring elastomer, thereby making it possible to effectively cool the object to be cooled.

[0027] A ninth aspect is the cooling heat exchanger according to any one of the first to eighth aspects, wherein the cooling heat passage member includes a heat pipe.

[0028] According to a cooling heat exchanger constructed in accordance with this embodiment, a heat transfer elastic body is formed on the surface of the low-temperature part of the heat pipe to set up a cooling surface, thereby making it possible to effectively cool the object to be cooled that is placed over the cooling surface.

[0029] A tenth aspect is a cooling heat exchanger described in any one of the first to ninth aspects, wherein the heat transfer elastic body is provided with a plurality of cooling surfaces, and a plurality of cooling objects are respectively superimposed on the plurality of cooling surfaces.

[0030] According to the cooling heat exchanger constructed in accordance with this aspect, a single cooling heat exchanger can cool multiple cooling targets. The multiple cooling targets may be, for example, separate components, or multiple different locations on a single component.

[0031] In an eleventh aspect, in the cooling heat exchanger described in the tenth aspect, the heat transfer elastic body is plate-shaped, a pair of the cooling surfaces is provided on both sides of the heat transfer elastic body in the plate thickness direction, and each of the pair of cooling surfaces is superimposed on each of the different cooling objects.

[0032] According to the cooling heat exchanger constructed in accordance with this aspect, two cooling targets can be cooled by one cooling heat exchanger. Also, for example, by arranging the cooling heat exchangers and the cooling targets alternately in the thickness direction of the heat transfer elastic body and stacking them in a stacked state, both sides of each cooling target can be cooled by the cooling heat exchanger.

[0033] In a twelfth aspect, in the cooling heat exchanger described in any one of the first to eleventh aspects, the cooling heat path members are arranged in parallel in at least a portion, and the orientation rate of the heat conductive filler in the portion of the heat transfer elastomer arranged between adjacent cooling heat path members is lower than the orientation rate of the heat conductive filler in the portion of the heat transfer elastomer arranged between the cooling heat path members and the cooling surface.

[0034] In a cooling heat exchanger constructed according to this embodiment, for example, the thermally conductive filler is oriented in the opposing direction of the cooling heat path member and the cooling surface between the opposing cooling heat path member and the cooling surface, thereby increasing the thermal conductivity between the cooling heat path member and the cooling surface, and in parts outside the opposing space between the cooling heat path member and the cooling surface, the orientation rate of the thermally conductive filler is reduced and the filler is scattered, making it easier for heat to be transferred from the cooling heat path member arranged nearby.

[0035] In a thirteenth aspect, in the cooling heat exchanger according to any one of the first to twelfth aspects, the heat transfer elastic body is a foam.

[0036] In a cooling heat exchanger constructed according to this aspect, the flexibility of the heat transfer elastic body can be increased, improving the ability of the cooling surface to follow the deformation of the cooling object. In addition, the density of the heat transfer elastic body can be reduced, making it easier to reduce the weight of the cooling heat exchanger.

[0037] A fourteenth aspect is a method for manufacturing a cooling heat exchanger for cooling an object to be cooled, comprising a preparation step of preparing a cooling heat path member, and a molding step of filling a forming material, in which a large number of heat conductive fillers made of a magnetic material are mixed into an elastic base material, into a cavity of a molding die in which the cooling heat path member is set, and insert molding a heat transfer elastic body having a cooling surface to be superimposed on the object to be cooled so that it is in close contact with the surface of the cooling heat path member, and in the molding step, a magnetic field is applied between the opposing surfaces of the cooling heat path member and the cooling surface to orient the heat conductive fillers in the opposing direction of the cooling heat path member and the cooling surface.

[0038] According to the manufacturing method of the cooling heat exchanger of this embodiment, in the molding process of the heat transfer elastomer, by applying a magnetic field to the material for forming the heat transfer elastomer filled in the cavity of the molding die, the heat conductive filler can be easily oriented in the opposing direction between the heat path member for cooling and the cooling surface.

[0039] Furthermore, when a magnetic field is applied to the material forming the heat transfer elastic body, the orientation rate of the thermally conductive filler in the portion outside the area between the heat path member for cooling and the cooling surface may be made lower than that between the heat path member for cooling and the cooling surface, for example, by hindering the action of the magnetic field or by reducing the magnetic force acting thereon. This allows the thermally conductive filler to be dispersed in that portion, thereby making it possible to suppress a decrease in the amount of heat transferred from the cooling surface to the heat path member for cooling in that portion.

[0040] A fifteenth aspect is a method for manufacturing a cooling heat exchanger for cooling an object to be cooled, comprising: a preparation step of preparing a cooling heat passage member; and a molding step of filling a forming material, in which a large number of heat-conducting fillers made of a magnetic material are mixed into an elastic base material, into a cavity of a molding die in which the cooling heat passage member is set, and insert-molding a heat-transferring elastic body having a cooling surface to be superimposed on the object to be cooled so that it is in close contact with the surface of the cooling heat passage member. In the molding step, a magnetic field inclined with respect to the opposing direction of the cooling heat passage member and the cooling surface is applied to the heat-conducting fillers, so that the large number of heat-conducting fillers are oriented in a direction inclined with respect to the opposing direction of the cooling heat passage member and the cooling surface.

[0041] According to the manufacturing method of the cooling heat exchanger of this embodiment, in the molding process of the heat transfer elastomer, a magnetic field is applied to the material for forming the heat transfer elastomer filled in the cavity of the molding die, so that the heat conductive filler made of a magnetic material can be easily oriented in a specific direction.

[0042] By orienting the thermally conductive filler in a direction inclined relative to the opposing direction between the cooling heat path member and the cooling surface, it becomes possible to adjust the heat transfer efficiency in the opposing direction between the cooling heat path member and the cooling surface, and as exemplified in the embodiment described below, when the object to be cooled is pressed against the cooling surface and the heat transfer elastomer is compressed, it becomes possible to improve cooling performance by taking advantage of the fact that the thermally conductive fillers come closer to each other.

[0043] According to the present invention, a cooling heat exchanger can stably achieve high cooling efficiency with a simple configuration having a small number of parts.

[0044] 1 is a perspective view showing a cooling heat exchanger according to a first embodiment of the present invention; a front view of the cooling heat exchanger shown in FIG. 1; a plan view of the cooling heat exchanger shown in FIG. 1; an enlarged view of the IV-IV cross section of FIG. 2; a cross-sectional view showing a molding process of the cooling heat exchanger shown in FIG. 1; a perspective view of the cooling heat exchanger shown in FIG. 1 in use; a plan view of the cooling heat exchanger shown in FIG. 6 in use; a cross-sectional view of a cooling heat exchanger according to a second embodiment of the present invention, corresponding to the VIII-VIII cross section of FIG. 9; a IX-IX cross-sectional view of FIG. 8; a cross-sectional view of a cooling heat exchanger according to a third embodiment of the present invention; and a cross-sectional view showing a molding process of a cooling heat exchanger according to another embodiment of the present invention.

[0045] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0046] 1 to 4 show a cooling heat exchanger 10 according to a first embodiment of the present invention. The cooling heat exchanger 10 is a heat exchanger for cooling a battery pack 34, which will be described later, and has a structure in which a heat transfer elastic body 14 is formed in intimate contact with the surface of a pipe member 12 that constitutes a heat passage member for cooling.

[0047] The pipe member 12 is made of metal, synthetic resin, etc. The pipe member 12 is preferably made of a non-magnetic material, for example, a non-magnetic metal material such as an aluminum alloy, or a synthetic resin such as polyamide. The pipe member 12 may be, for example, a seamless pipe formed without seams by drawing or extrusion, or may be an electric resistance welded pipe made by rolling a plate material and welding part of its circumference, or a forge welded pipe made by forging.

[0048] The pipe member 12 has an inner hole that serves as a cooling passage 16 through which a heat transfer medium (refrigerant) for cooling flows. The heat transfer medium for cooling that flows through the cooling passage 16 is not particularly limited and may be a gas such as air, but is preferably a liquid such as water or an antifreeze such as ethylene glycol.

[0049] The pipe member 12 extends in a serpentine shape with a folded-back intermediate portion, and includes a plurality of straight portions 18 extending linearly in the left-right direction and a plurality of folded-back portions 20 extending in a semicircular arc, arranged alternately along the length. The plurality of straight portions 18, 18 are arranged parallel to each other and spaced apart in the up-down direction. The pipe member 12 may have a constant cross-sectional shape and area along its entire length. However, in this embodiment, as shown in FIGS. 2 and 3 , both end portions protruding from the heat transfer elastic body 14 (described later) have a substantially circular cross-section, and the intermediate portion, which is fixed and embedded in the heat transfer elastic body 14, has a flat, substantially oval cross-section and is wide when projected in the front-to-rear direction, which is the thickness direction of the heat transfer elastic body 14 (the direction perpendicular to the cooling surface 26 of the heat transfer elastic body 14 (described later)).

[0050] The heat transfer elastic body 14 has flexibility that allows it to easily deform under the action of an external force. When the battery pack 34 (described later) abuts against the heat transfer elastic body 14, the heat transfer elastic body 14 is compressed between the abutment surface of the battery pack 34 and the pipe member 12, and its surface has flexibility that allows it to deform to follow the abutment surface of the battery pack 34. The heat transfer elastic body 14 also has elasticity that allows it to restore its shape when the input is released. The heat transfer elastic body 14 preferably has a Young's modulus of 0.5 MPa or less, and more preferably 0.2 MPa or less. The heat transfer elastic body 14 is formed from a material in which a thermally conductive filler 24 made of metal or the like is mixed into an elastic substrate 22 made of rubber or resin elastomer.

[0051] The elastic substrate 22 is formed of rubber or a resin elastomer, and is preferably formed of polyurethane foam, such as that disclosed in Japanese Patent Application Laid-Open No. 2009-051148. The elastic substrate 22 is preferably a foam, which improves flexibility. However, the elastic substrate 22 is not limited to a foam, and may be a non-foamed material. Note that, in the cross-sectional views shown in Figures 4 and 5 (described below), air bubbles in the elastic substrate 22 are omitted for clarity.

[0052] The thermally conductive filler 24 is made of a material with high thermal conductivity, such as metal, and can be formed into various shapes, such as spherical (including oval and ellipsoidal), columnar, conical, foil, fibrous, etc. The thermally conductive filler 24 is sized so that a large number of pieces can be mixed with the elastic substrate 22, and it is desirable that the maximum outer dimension be set within the range of 0.1 mm to 5 mm, for example.

[0053] The thermally conductive filler 24 is preferably formed from a magnetic material. Examples of suitable magnetic materials include ferromagnetic materials, antiferromagnetic materials, and alloys thereof, as disclosed in JP 2009-051148 A. Specifically, the thermally conductive filler 24 may be formed from ferromagnetic materials such as iron, stainless steel, nickel, and cobalt, antiferromagnetic materials such as manganese oxide, chromium oxide, and iron chloride, and alloys thereof. The magnetic thermally conductive filler 24 is preferably formed from stainless steel, which has excellent corrosion resistance, or a copper-iron alloy, which has excellent both magnetic properties and thermal conductivity. Another example of the magnetic thermally conductive filler 24 may be a composite particle formed by combining graphite or other magnetic particles, as disclosed in WO 2013 / 042611 A.

[0054] 2 to 4, the heat transfer elastic body 14, which is made of a material in which a heat conductive filler 24 is mixed into an elastic base material 22, is provided to cover the middle portion of the pipe member 12. The heat transfer elastic body 14 has a generally rectangular flat plate shape with the thickness direction being the front-to-rear direction, and the multiple straight portions 18 and folded portions 20 of the pipe member 12 are embedded inside the heat transfer elastic body 14, while both ends of the pipe member 12 protrude rightward from the heat transfer elastic body 14 and are exposed to the outside.

[0055] When the pipe member 12 is heated or cooled, the heat of the pipe member 12 is transferred to the surface of the heat transfer elastic body 14 by the heat conductive filler 24 blended into the heat transfer elastic body 14. The pipe member 12 is cooled by the cooling heat medium flowing through the cooling passage 16 inside, and the surface of the heat transfer elastic body 14 is cooled by heat exchange with the pipe member 12.

[0056] The front-to-rear surface of the heat transfer elastic body 14, which is the plate thickness direction, is closer to the pipe member 12 than the top-bottom and left-to-right surfaces of the heat transfer elastic body 14, making it easier to transfer heat from the pipe member 12. The front and rear surfaces of this heat transfer elastic body 14 are overlaid on a battery pack 34, which will be described later, and serve as cooling surfaces 26, 26 that cool the battery pack 34. In this embodiment, both sides of the heat transfer elastic body 14 in the thickness direction, which is shaped like a substantially rectangular plate, are each served as a cooling surface 26, and two cooling surfaces 26, 26 are set for one heat transfer elastic body 14.

[0057] The cooling surface 26 is part of the surface of the heat transfer elastic body 14, and is therefore allowed to deform in response to the action of an external force. Therefore, when a battery pack 34 (described later) is pressed against the cooling surface 26, the cooling surface 26 deforms to conform to the surface of the battery pack 34, allowing the cooling surface 26 and the battery pack 34 to be superimposed in close contact with each other without any gaps.

[0058] As shown in Fig. 5, the heat transfer elastic body 14 is formed by filling a molding material, which is a mixture of an elastic base material 22 and a thermally conductive filler 24, into a cavity 30 of a molding die 28 with the pipe member 12 set in the molding die 28. A method for manufacturing the cooling heat exchanger 10 will be described below with reference to Fig. 5. Note that Fig. 5 illustrates an example of a molding die 28 made up of front and rear molding dies 28a, 28b, with the cavity 30 formed between the molding dies 28a, 28b, but the structure of the molding die 28 (number of divisions, direction of division, etc.) is not particularly limited.

[0059] First, a preparation process for preparing the pipe member 12 is performed. Specifically, for example, a seamless pipe made by drawing an aluminum alloy or an electric resistance welded pipe made by roll-forming an aluminum alloy strip and then electrically welding the pipe is manufactured into a straight shape. The straight pipe is then bent into a serpentine shape and its intermediate portion is flattened by pressing. In this pipe member 12 preparation process, the connecting pipes 38a, 38b may be attached to both ends of the pipe member 12 by welding or other means. Alternatively, the connecting pipes 38a, 38b may be attached to both ends of the pipe member 12 protruding from the heat transfer elastic body 14 after the heat transfer elastic body 14 molding process described below is completed. The pipe member 12 may be made of a synthetic resin. In this case, the pipe member 12 may be formed into a straight cylindrical shape and then bent, flattened, or the like. If the pipe member 12 is made of a synthetic resin, a thermoplastic resin material is preferably used, which allows for easy bending, flattening, and other processing by heating.

[0060] 5, the pipe member 12 is set between the molding dies 28a, 28b, and the middle portion of the pipe member 12 is placed in the cavity 30. The pipe member 12 is supported at both ends by being sandwiched between the molding dies 28a, 28b, but, for example, in order to hold the middle portion at a predetermined position in the cavity 30, a support pin that protrudes toward the pipe member 12 in the cavity 30 may be provided on at least one of the molding dies 28a, 28b.

[0061] Next, a molding process is performed in which the material for forming the heat transfer elastic body 14, which is the elastic base material 22 mixed with the thermally conductive filler 24, is filled into the cavity 30 of the molding die 28, and the heat transfer elastic body 14 is insert-molded by heating or cooling, etc. After molding of the heat transfer elastic body 14 is completed, the molding dies 28a, 28b are removed from the molded product, thereby completing the manufacturing process of the cooling heat exchanger 10. The cooling heat exchanger 10 is an integrally molded product in which the pipe member 12 is inserted into the heat transfer elastic body 14, and the heat transfer elastic body 14 is firmly attached to the surface of the pipe member 12 in a tight-fitting state. In the cooling heat exchanger 10 of this embodiment, the entire pipe member 12 is inserted into the heat transfer elastic body 14, but for example, the heat transfer elastic body 14 may be firmly attached to only the surface of the straight portion 18 of the pipe member 12 in a tight-fitting state. In this embodiment, a foaming agent such as sodium bicarbonate is blended into the material forming the heat transfer elastic body 14, and bubbles are formed during molding of the heat transfer elastic body 14, turning the heat transfer elastic body 14 into a foam. Note that the molding process for the heat transfer elastic body 14 can also employ the method for manufacturing a urethane foam molded body disclosed in Japanese Patent Application Laid-Open No. 2009-051148, for example.

[0062] 5 is formed to magnetize the thermally conductive filler 24, which is the material for forming the thermally conductive elastic body 14. This causes the thermally conductive filler 24 of the thermally conductive elastic body 14 to be oriented in the front-to-rear direction, forming a magnetic path that extends along the magnetic field lines of the applied magnetic field. The thermally conductive filler 24 oriented in the front-to-rear direction forms a thermally conductive path that extends in the front-to-rear direction, thereby improving the efficiency of heat transfer in the front-to-rear direction from the pipe member 12 to the cooling surfaces 26, 26.

[0063] In this embodiment, the pipe member 12 is formed from a non-magnetic material, and the pipe member 12 does not affect the magnetic field when the heat transfer elastic body 14 is molded, and the magnetic field in the front-to-back direction acts effectively on the part of the heat transfer elastic body 14 that overlaps with the pipe member 12 in the front-to-back direction.

[0064] The molding dies 28a, 28b are provided with shield members 32 that reduce or prevent the passage of magnetic flux in a portion that is outside the pipe member 12 in front-to-rear projection. The shield members 32 are made of a ferromagnetic material such as iron, and in this embodiment, are shaped like a long plate with a substantially rectangular cross section that extends in the left-right direction (the direction perpendicular to the plane of the paper in FIG. 5). In this embodiment, the shield members 32 are arranged so as to be located between the straight portions 18, 18 that are adjacent to each other in the vertical direction in front-to-rear projection.

[0065] During the molding process of the heat transfer elastic body 14, the shield member 32 reduces the effect of a magnetic field on the heat conductive filler 24 in the portion of the heat transfer elastic body 14 that is laterally offset from the pipe member 12. That is, when a magnetic field is generated in the front-to-rear direction, the ferromagnetic shield member 32 forms a magnetic path in the portion where the shield member 32 is disposed. This leads to magnetic flux being guided in the longitudinal direction of the shield member 32, i.e., the left-to-right direction, making it less likely to affect the heat conductive filler 24 of the heat transfer elastic body 14. The orientation rate of the heat conductive filler 24 in the front-to-rear direction is lower than that of the portion of the cooling surface 26 that overlaps with the pipe member 12 in front-to-rear projection, and the heat conductive filler 24 is more randomly distributed. Therefore, in the portion of the heat transfer elastic body 14 that is laterally offset from the pipe member 12, efficient heat exchange occurs between the pipe member 12 and the heat conductive elastic bodies 14 on either side of the pipe member 12, and the cooling surface 26 is likely to be at a low temperature even in the portion that is laterally offset from the pipe member 12. However, in the portion of the cooling surface 26 that overlaps with the pipe member 12 in the front-to-back projection, the heat-conducting filler 24 is oriented in the front-to-back direction and is cooled more efficiently by the pipe member 12, so it exhibits a better cooling effect than the portion that is off the pipe member 12 in the left-to-right direction.

[0066] The orientation rate (degree of orientation) of the thermally conductive filler 24 in the thermally conductive elastomer 14 can be measured, for example, based on the thermal conductivity of the thermally conductive elastomer 14. That is, the higher the orientation rate of the thermally conductive filler 24 in a specific direction (orientation direction), the higher the thermal conductivity in the orientation direction. Therefore, in a thermally conductive elastomer 14 formed from a uniform material, the higher the thermal conductivity in a specific direction, the higher the orientation rate of the thermally conductive filler 24 in the specific direction. Because the cooling heat exchanger 10 requires heat transfer performance from the pipe member 12 to the cooling surface 26, the level of the orientation rate of the thermally conductive filler 24 is measured based on the heat transfer coefficient in the opposing direction between the pipe member 12 and the cooling surface 26.

[0067] The orientation rate of the thermally conductive filler 24 in the thermally conductive elastomer 14 can also be calculated based on the results of measuring the distance between the thermally conductive filler particles 24 in a specific direction using, for example, X-ray irradiation. The orientation rate of the thermally conductive filler 24 can be calculated based on the arithmetic mean value, median value, etc. of the distance between the thermally conductive filler particles 24.

[0068] The cross-sectional shape of the shield member 32 is not limited to a rectangle, and various other shapes may be adopted, such as a circle, a square, a trapezoid, a parallelogram, or an irregular shape. Furthermore, for example, a shield member 32 with a rectangular cross section may be arranged so as to be inclined with respect to the magnetic field lines. The multiple shield members 32 are not limited to having a uniform cross-sectional shape or cross-sectional area, and when arranged so as to be inclined with respect to the magnetic field lines, the inclination angle and inclination direction may be different from each other.

[0069] As shown in Figures 6 and 7 , the cooling heat exchanger 10 configured as described above is used in a state where it is superimposed on a battery pack 34 to be cooled. That is, at least one of the cooling surfaces 26, 26 provided on the front and rear surfaces of the cooling heat exchanger 10 is superimposed in contact with the surface of the battery pack 34. Figures 6 and 7 show a battery module 36 with a heat exchanger in which multiple cooling heat exchangers 10 and multiple battery packs 34 are alternately stacked in the front-to-rear direction. As shown in Figures 6 and 7 , the cooling heat exchangers 10, 10 are disposed on both the front and rear of the battery pack 34. In other words, one of the two battery packs 34, 34 is superimposed on the cooling surface 26, 26 of one cooling heat exchanger 10 located in the middle between the front and rear. In addition, the three cooling heat exchangers 10, 10, 10 located in the middle between the front and rear have their cooling surfaces 26, 26 on both the front and rear sides superimposed on the battery pack 34, and the two cooling heat exchangers 10, 10 located at the ends between the front and rear have only one cooling surface 26 on each side superimposed on the battery pack 34.

[0070] In each of the multiple cooling heat exchangers 10, both ends of the pipe members 12 protrude rightward from the heat transfer elastic body 14. Connecting pipes 38 extending in the front-to-rear direction and provided at the ends of the pipe members 12 are connected to each other, and a common pipe 40 extending in the front-to-rear direction is formed by these connecting pipes 38. The connecting pipes 38 are provided at both ends of the pipe members 12, respectively, and the common pipe 40a located at the top is formed by connecting the connecting pipes 38a provided at one end of each pipe member 12, and the common pipe 40b located at the bottom is formed by connecting the connecting pipes 38b provided at the other end of each pipe member 12.

[0071] The cooling heat medium that flows into each cooling passage 16 of the multiple cooling heat exchangers 10 through the common pipe 40a flows through the cooling passage 16, cools the pipe members 12, and is then discharged to the outside through the common pipe 40b. One end opening of the common pipe 40a and one end opening of the common pipe 40b are each closed. The other end opening of the common pipe 40a and the other end opening of the common pipe 40b are mutually connected by an external flow path (not shown). As a result, a circulation path through which the cooling heat medium circulates is formed, including the cooling passages 16 in the middle portions of the pipe members 12. The external flow path is equipped with a compressor or the like for cooling the cooling heat medium.

[0072] The pipe member 12, cooled by the cooling heat medium flowing through the cooling passage 16, cools the heat transfer elastic body 14 covering the outside of the intermediate portion. Because the heat transfer elastic body 14 contains a large number of heat conductive fillers 24, the heat transfer action of the heat conduction path formed by these heat conductive fillers 24 efficiently realizes heat exchange between the pipe member 12 and cooling surfaces 26, 26, which are the front and rear surfaces of the heat transfer elastic body 14, and the cooling surfaces 26, 26 are cooled.

[0073] The battery packs 34 placed on the cooling surfaces 26, which have been set to a low temperature, are cooled by the cooling heat exchangers 10 that include the cooling surfaces 26, thereby preventing deterioration in charge / discharge performance, durability, and the like due to high temperatures of the battery packs 34. In this embodiment, both the front and rear surfaces of each battery pack 34 are placed on the cooling surfaces 26 of the cooling heat exchangers 10, 10, and therefore both the front and rear surfaces of each battery pack 34 are cooled.

[0074] When the battery pack 34 is pressed against the cooling surface 26 formed by the surface of the heat transfer elastic body 14, the cooling surface 26 is deformed to conform to the surface shape of the battery pack 34, and the cooling surface 26 is closely fitted over the battery pack 34 with no gaps. In this way, because the cooling surface 26 of the cooling heat exchanger 10 is formed by the surface of the heat transfer elastic body 14, the cooling surface 26 can be closely fitted to the battery pack 34 without the need for a thermally conductive material to fill the gap between the cooling surface 26 and the battery pack 34. As a result, efficient heat conduction between the cooling surface 26 and the battery pack 34 can be ensured with a simple structure with a small number of parts.

[0075] The heat conduction path is a path that easily transfers heat due to the mutual contact or proximity of a large number of heat conductive fillers 24, and is provided between the pipe member 12 and the cooling surfaces 26, 26. In this embodiment, the heat conductive fillers 24 are oriented so as to be aligned linearly in the front-to-rear direction between the pipe member 12 and the opposing cooling surfaces 26, 26 when the heat transfer elastic body 14 is molded. Therefore, the heat conduction path is configured to extend in the front-to-rear direction between the pipe member 12 and the opposing cooling surfaces 26, 26. Therefore, efficient heat exchange is achieved between the pipe member 12 and the opposing cooling surfaces 26, 26 due to the heat transfer action of the heat conduction path, and excellent cooling performance can be obtained.

[0076] Furthermore, in the portions of the heat transfer elastic body 14 that are laterally separated from the pipe member 12, the orientation rate of the heat conductive filler 24 is low, forming heat conduction paths that extend in multiple directions. As a result, the portions of the cooling surface 26 that are not facing the pipe member 12 in the front-to-rear direction are also cooled by the nearby pipe member 12, thereby achieving effective cooling performance.

[0077] In this embodiment, the heat passage member is formed of a pipe member 12, and a cooling heat medium flows through a cooling passage 16 formed by the inner hole of the pipe member 12. As a result, even if the pipe member 12 is heated by heat exchange with the battery pack 34, the heat of the pipe member 12 is quickly removed by the cooling heat medium flowing through the cooling passage 16, so that the pipe member 12 is maintained at a low temperature. Therefore, even when the cooling heat exchanger 10 is used continuously, deterioration of cooling performance is unlikely to be a problem, and the battery pack 34 can be stably cooled.

[0078] The cooling heat exchanger 10 of this embodiment has multiple cooling surfaces 26, allowing multiple battery packs 34 to be cooled simultaneously. Furthermore, since the cooling heat exchanger 10 of this embodiment has cooling surfaces 26 on both the front and rear surfaces of the heat transfer elastomer 14, multiple heat transfer elastomers 14 and multiple battery packs 34 can be alternately stacked to cool any number of battery packs 34. Therefore, an effective cooling structure can be provided using a cooling heat exchanger 10 with a common structure for multiple types of electric vehicles, etc., with different numbers of battery packs 34. While this embodiment illustrates a battery module 36 capable of cooling four battery packs 34, the number of battery packs 34 may be three or less, or five or more, and this can be accommodated by increasing or decreasing the number of cooling heat exchangers 10 depending on the number of battery packs 34 to be cooled.

[0079] 8 and 9 show a cooling heat exchanger 50 according to a second embodiment of the present invention. The cooling heat exchanger 50 has a structure in which a heat transfer elastic body 14 is formed in intimate contact with the surface of a bag body 52 serving as a heat passage member. In the following description, members and parts that are substantially the same as those in the first embodiment are designated by the same reference numerals in the drawings, and description thereof will be omitted.

[0080] The bag body 52 has a structure in which, for example, two aluminum pouches each having a resin film bonded to both sides of an aluminum foil are stacked together, and the outer edges of the aluminum pouches are bonded together. The outer edges of the bag body 52 are sealed by, for example, heat sealing the outer edges together over almost the entire circumference. Note that the bag body 52 can also be formed from a laminate film in which another resin film is bonded to the aluminum film vapor-deposited on a resin film so as to cover the vapor-deposited surface.

[0081] A cooling passage 54 through which a heat transfer medium for cooling flows is formed inside the bag body 52. ​​As shown in Fig. 8, the cooling passage 54 extends in a serpentine shape, first extending linearly and then turning back, with both ends located at the right ends of the upper and lower sides of the bag body 52. ​​The cooling passage 54 is formed into a predetermined shape (path) by, for example, partially heat-sealing a pair of aluminum pouches that make up the bag body 52 in the middle between the upper and lower parts. The shape of the cooling passage 54 is not particularly limited, but a passage shape that has a large projected area in the front-to-rear direction and that makes it easy to control the flow of the heat transfer medium for cooling is desirable.

[0082] A supply port 56 and a discharge port 58 are provided at each end of the cooling passage 54. The supply port 56 and the discharge port 58 are both cylindrical members made of metal, hard synthetic resin, or the like, with one end (the left end) penetrating the bag body 52 and communicating with the cooling passage 54, and the other end (the right end) protruding rightward from the bag body 52 and connected to an external flow path (not shown). The supply port 56 and the discharge port 58 are inserted between the overlapping surfaces of a pair of aluminum pouches constituting the bag body 52 and penetrate the heat-sealed portions at the outer peripheral ends. The pair of aluminum pouches constituting the bag body 52 are fixed to the outer peripheral surfaces of the supply port 56 and the discharge port 58 at the penetrating portions of the supply port 56 and the discharge port 58 by means of welding, adhesive, or the like, thereby sealing the overlapping surfaces of the bag body 52 and the supply port 56 and the discharge port 58.

[0083] The heat transfer elastomer 14 is formed in close contact with the surface of the bag 52. In this embodiment, the heat transfer elastomer 14 has a rectangular plate-like outer shape similar to that of the first embodiment, and both the front and rear surfaces of the heat transfer elastomer 14 serve as cooling surfaces 26. The thermally conductive fillers 24 of the heat transfer elastomer 14 may be oriented, for example, linearly aligned in the front-rear direction, or may be dispersed without being oriented in a specific direction. As in the first embodiment, the orientation of the thermally conductive fillers 24 may be different between the portion where the cooling passage 16 and the cooling surface 26 face each other in the front-rear direction and the portion vertically offset from the cooling passage 54, such that the orientation rate in the portion vertically offset from the cooling passage 54 is lower than that in the portion that overlaps with the cooling passage 54 in the front-rear projection.

[0084] As shown in Fig. 9 , the cooling heat exchanger 50 configured as described above cools the battery packs 34 by placing the battery packs 34 on the cooling surfaces 26 provided on both the front and rear sides. The heat transfer elastic body 14 is interposed between the bag 52, which is cooled by the cooling heat medium flowing through the cooling passage 54, and the battery pack 34 to be cooled. This allows the bag 52 and the battery pack 34 to be in close contact with each other via the heat transfer elastic body 14, which has excellent heat conductivity, thereby achieving efficient heat exchange between the bag 52 and the battery pack 34. In particular, in this embodiment, the heat passage member formed by the bag 52 itself is allowed to deform in response to an external force, so the cooling surfaces 26 can more easily conform to the surface of the battery pack 34, more reliably achieving close contact between the cooling surfaces 26 and the battery pack 34.

[0085] Furthermore, in the cooling heat exchanger 50 of this embodiment, the heat path member is formed of the bag 52, and therefore the heat path member is lighter and easier to manufacture than when the heat path member is formed of the pipe member 12. Note that the heat sealing for setting the shape of the cooling path 54 can be performed simultaneously with the heat sealing of the outer peripheral edge of the bag 52, and the bag 52 with the cooling path 54 can be obtained with fewer manufacturing steps.

[0086] Because the surface of the bag 52 is covered with the heat transfer elastic body 14, the bag 52 does not come into direct contact with the battery pack 34. Therefore, even if the heat passage member is made of the bag 52, which is more susceptible to damage due to friction and the like than the pipe member 12, a decrease in durability due to contact with the battery pack 34 is unlikely to be a problem.

[0087] 10 shows a cooling heat exchanger 70 according to a third embodiment of the present invention. The cooling heat exchanger 70 has a structure in which the surface of a heat passage member 72 for cooling is covered with a heat transfer elastic body 14.

[0088] The heat passage member 72 is generally rectangular in shape and includes a passage forming member 74 made of synthetic resin and a pair of heat-transfer lids 76, 76 superimposed on both sides in the thickness direction of the passage forming member 74. Fig. 10 corresponds to Fig. 9 in the second embodiment, and the cross section at the center of the front-to-rear direction perpendicular to the front-to-rear direction is generally the same as Fig. 8.

[0089] The passage forming member 74 is a thick, generally rectangular plate. The passage forming member 74 is made of a hard synthetic resin, such as polypropylene, polyamide, polyethylene, polyester, or polycarbonate. The passage forming member 74 may also be made of a fiber-reinforced resin.

[0090] A through-hole 78, which serves as a serpentine void, is formed through the passage forming member 74 in the thickness direction. One of the supply port 56 and one of the discharge port 58 are connected to both ends of the through-hole 78 in the longitudinal direction, and the supply port 56 and the discharge port 58 protrude rightward from the passage forming member 74.

[0091] The heat-conductive lid 76 has a higher heat transfer coefficient than the passage-forming member 74, and its outer shape when viewed from the front to back generally corresponds to that of the passage-forming member 74. The heat-conductive lid 76 may be a plate made of metal or synthetic resin. For example, it may be a laminated film in which resin films are bonded to both sides of a metal foil, such as the aluminum pouch constituting the bag body 52 of the second embodiment, or a laminated film in which a resin film is bonded to an aluminum vapor-deposited film. The heat-conductive lid 76 is thinner than the passage-forming member 74. The heat-conductive lid 76 is overlapped on the front and rear surfaces of the passage-forming member 74 and fixed to the passage-forming member 74 by means such as heat welding or adhesive. The overlapping surfaces of the passage-forming member 74 and the heat-conductive lid 76 are fluid-tightly sealed at least around the through-hole 78.

[0092] The front and rear openings of the through-hole 78 are covered with heat-transfer lids 76, 76, and a serpentine cooling passage 80 is formed between the heat-transfer lids 76, 76 by utilizing the through-hole 78. The supply port 56 and the discharge port 58 are connected to both ends of the cooling passage 80, and the heat medium for cooling supplied and discharged through the supply port 56 and the discharge port 58 flows through the cooling passage 80.

[0093] The heat passage member 72 is disposed in a buried state with the supply port 56 and the discharge port 58 protruding from the heat transfer elastic body 14. The heat transfer elastic body 14 is formed by tightly covering the front and rear outer surfaces of the heat transfer lids 76, 76, and these front and rear outer surfaces serve as the cooling surfaces 26, 26. Heat exchange occurs between the low-temperature heat medium flowing through the cooling passage 80 and the heat transfer elastic body 14 via the heat transfer lids 76, 76, thereby cooling the cooling surfaces 26, 26 and maintaining them at a low temperature.

[0094] According to the cooling heat exchanger 70 of this embodiment, the cooling passage 80 is formed using the through holes 78 provided in the hard passage-forming member 74, which stabilizes the passage shape of the cooling passage 80 and makes it easier to obtain stable cooling performance.

[0095] Furthermore, since the passage-forming member 74 is made of synthetic resin, which has a lower specific gravity than metals such as aluminum alloys, an increase in the weight of the cooling heat exchanger 70 is suppressed. Moreover, the heat-conducting lid 76, whose thermal conductivity significantly affects cooling performance, is a separate component from the passage-forming member 74. Therefore, it is possible to use a component made of a different material from the passage-forming member 74, making it easy to set a high thermal conductivity. In addition, the heat-conducting lid 76 of this embodiment is film-shaped and is significantly thinner than the passage-forming member 74, thereby achieving more efficient heat exchange between the cooling heat medium flowing through the cooling passage 80 and the heat-conducting elastomer 14.

[0096] In this embodiment, the cooling passages 80 are formed by the through holes 78 that penetrate the passage-forming member 74. However, for example, a recessed groove that opens on only one surface of the passage-forming member 74 can be covered with a heat-transfer lid 76 to form the cooling passage by utilizing the recessed groove. In this case, the cooling surface 26 is set only on the surface of the heat-transfer elastic body 14 on the opening side of the recessed groove.

[0097] The heat-conductive lid may be, for example, a metal plate made of aluminum alloy, stainless steel, etc., and is not necessarily limited to a sheet shape. Furthermore, for example, the sealing between the overlapping surfaces of the passage-forming member and the heat-conductive lid may be realized by providing a seal member between the overlapping surfaces of the passage-forming member and the heat-conductive lid, and may be a structure separate from the fixing structure between the passage-forming member and the heat-conductive lid, such as welding or bonding.

[0098] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the specific descriptions. For example, the heat path member may be capable of maintaining a low temperature at least in part by allowing heat transfer, and the heat path member is not limited to the structure illustrated in the above embodiment, which includes a cooling path 16 through which a cooling heat medium flows. Specifically, for example, the heat path member may be configured as a heat pipe, and cooling performance may be achieved by heat exchange between the low-temperature portion of the heat pipe and the cooling surface. It is also possible to combine multiple types of heat path members with different structures, such as the heat path members 12, 52, and 72 shown in the first to third embodiments and heat path members made of heat pipes.

[0099] In the first embodiment, both ends of the pipe member 12 protruded from the heat transfer elastic body 14 to the same side (right side) in the left-right direction, but they may protrude, for example, to one side each, or to both sides or either side in the up-down direction.

[0100] In the first embodiment, a pipe member 12 having a flattened middle portion embedded in the heat transfer elastic body 14 is exemplified, but when the heat passage member is constructed from a pipe member, the pipe member may have a uniform cross-sectional shape as a whole, for example, a circular cross-section as a whole.

[0101] A single heat transfer elastic body 14 can also be formed on the surfaces of multiple pipe members. That is, by arranging multiple linearly extending pipe members in parallel and forming a single heat transfer elastic body 14 on the surfaces of the multiple pipe members, multiple cooling passages can be provided that extend linearly through a single heat transfer elastic body 14.

[0102] The cooling surfaces 26 do not necessarily have to be provided on both surfaces of the heat transfer elastomer 14, but may be provided on the front and top surfaces, for example. Also, separate cooling surfaces 26 may be provided in multiple locations on one surface of the heat transfer elastomer 14. Note that the up-down, front-rear, and left-right directions in the above-described embodiments are set merely for the convenience of explanation and do not limit the orientation of the cooling heat exchanger 10 in use. Specifically, for example, the cooling heat exchanger 10 may be used with the cooling surfaces 26 superimposed on the bottom surface of the battery pack 34.

[0103] In the first embodiment, an example was shown in which a magnetic field is formed in the front-rear direction, which is the plate thickness direction, during molding of the heat transfer elastic body 14, thereby orienting the heat conductive filler 24 in the front-rear direction, but the direction in which the heat conductive filler 24 is oriented is not necessarily limited to the direction perpendicular to the cooling surface 26 of the heat transfer elastic body 14. Specifically, as in the case of a heat transfer elastic body 90 constituting a cooling heat exchanger shown in Figure 11, for example, during the molding process of the heat transfer elastic body 90, a magnetic field can be applied in a direction inclined (the direction of the arrow in Figure 11) with respect to the direction perpendicular to the cooling surface 26 of the heat transfer elastic body 90 (the front-rear direction, which is the plate thickness direction), so that the heat conductive filler 24 is oriented in a direction inclined with respect to the direction perpendicular to the cooling surface 26.

[0104] A cooling heat exchanger including a heat transfer elastomer 90 with the heat conductive fillers 24 oriented in an oblique direction makes it possible to adjust the heat transfer characteristics, for example, by taking into account compressive deformation of the heat transfer elastomer 90. Specifically, when an object to be cooled (not shown) is pressed against the cooling surface 26 and the heat transfer elastomer 90 is compressed in a direction perpendicular to the cooling surface 26, the distance between the heat conductive fillers 24 decreases not only in the direction perpendicular to the cooling surface 26 but also in a direction parallel to the cooling surface 26. This achieves high heat exchange efficiency between the pipe member 12 and the cooling surface 26, and also makes it easier for the pipe member 12 to cool portions of the cooling surface 26 that are outside the pipe member 12 in front-to-back projection, allowing the object to be effectively cooled over a wider area of ​​the cooling surface 26. Furthermore, for example, by utilizing the fact that the compression rate in the direction perpendicular to the cooling surface 26 of the heat transfer elastic body 90 differs between the area where the pipe member 12 is present and the area outside of it due to the partial presence of the pipe member 12, it is possible to create a more efficient heat transfer path by bringing the heat conductive fillers 24 closer together in the area where the pipe member 12 is present not only in the arrangement direction but also between adjacent arrangements.

[0105] The thermally conductive filler may be any material capable of transferring heat between the heat path member and the cooling surface, and is not necessarily limited to being made of a magnetic material. Thermally conductive fillers made of non-magnetic materials can be oriented in a specific direction by means other than the action of a magnetic field, such as by controlling the injection direction of the material forming the thermally conductive elastomer 14 into the cavity. While it is desirable for the thermally conductive filler to be oriented in a specific direction from the perspective of efficient heat transfer, the thermally conductive filler may also be randomly dispersed without being oriented in a specific direction. Even in this case, an effective thermal conduction path can be formed by shortening the distance between the thermally conductive fillers, for example, by increasing the thermally conductive filler content in the thermally conductive elastomer or by pressing the cooling target against the cooling surface to compress the thermally conductive elastomer in a specific direction.

[0106] The object to be cooled is not limited to the battery pack 34 exemplified in the above embodiment, but may be, for example, a control device that includes an electronic circuit or the like as a heat generating element.

[0107] REFERENCE SIGNS LIST 10 Cooling heat exchanger (first embodiment) 12 Pipe member (heat passage member) 14 Heat-transferring elastic body 16 Cooling passage 18 Straight portion 20 Folded portion 22 Elastic base material 24 Heat-conducting filler 26 Cooling surface 28 (28a, 28b) Molding die 30 Cavity 32 Shield member 34 Battery pack (cooling target) 36 Battery module 38 (38a, 38b) Connecting pipe 40 (40a, 40b) Common pipe 50 Cooling heat exchanger (second embodiment) 52 Bag body (heat passage member) 54 Cooling passage 56 Supply port 58 Discharge port 70 Cooling heat exchanger (third embodiment) 72 Heat passage member 74 Passage-forming member 76 Heat-transferring lid 78 Through-hole 80 Cooling passage 90 Heat-transfer elastic body (another embodiment)

Claims

1. A cooling heat exchanger for cooling an object, comprising: a heat transfer elastomer, which is made of an elastic base material and a number of heat conductive fillers mixed therein, and which is formed in intimate contact with the surface of a heat passage member for cooling; a cooling surface is formed in the heat transfer elastomer, which is allowed to deform in accordance with the object to be cooled and is superimposed on the object to be cooled; and a heat conduction path between the cooling surface and the heat passage member for cooling is formed by the number of heat conductive fillers in the heat transfer elastomer.

2. A cooling heat exchanger as described in claim 1, wherein the numerous thermally conductive fillers are oriented in a straight line extending in the opposing direction between the thermal passage member for cooling and the cooling surface, so that the thermal conduction path is formed by the numerous thermally conductive fillers in a form extending in the opposing direction between the thermal passage member for cooling and the cooling surface.

3. A heat exchanger for cooling as described in claim 1 or 2, wherein the thermally conductive filler is formed of a magnetic material, and a large number of the thermally conductive fillers are oriented in a form that forms a magnetic path in a specific direction inside the heat-transfer elastomer.

4. A heat exchanger for cooling as claimed in any one of claims 1 to 3, wherein the heat passage member for cooling includes a pipe member, and the cooling passage through which the heat transfer medium for cooling flows is constituted by the inner hole of the pipe member.

5. A heat exchanger for cooling according to claim 4, wherein said pipe member is made of a non-magnetic material and said thermally conductive filler is made of a magnetic material.

6. A cooling heat exchanger as described in claim 4 or 5, wherein the portion of the pipe member fixed to the heat transfer elastomer is in the shape of a wide flat tube when projected in a direction perpendicular to the cooling surface.

7. A heat exchanger for cooling as described in any one of claims 1 to 6, wherein the heat passage member for cooling includes a bag body having a cooling passage therein through which a heat medium for cooling flows.

8. A heat exchanger for cooling as claimed in any one of claims 1 to 7, wherein the heat passage member for cooling has a structure in which a heat conductive lid is fixed in a laminated state to the surface of a passage forming member made of synthetic resin, the passage forming member is provided with a void that opens to the surface, the opening of the void is covered with the heat conductive lid to form a cooling passage through which a heat medium for cooling flows, and the heat conductive elastomer is formed in intimate contact with the surface of the heat conductive lid.

9. A heat exchanger for cooling according to any one of claims 1 to 8, wherein the thermal passage member for cooling includes a heat pipe.

10. A cooling heat exchanger as claimed in any one of claims 1 to 9, wherein the heat transfer elastomer is provided with a plurality of cooling surfaces, and a plurality of objects to be cooled are respectively superimposed on the plurality of cooling surfaces.

11. A cooling heat exchanger as described in claim 10, wherein the heat transfer elastomer is plate-shaped, a pair of cooling surfaces are provided on both sides of the heat transfer elastomer in the thickness direction, and different cooling objects are superimposed on each of the pair of cooling surfaces.

12. A heat exchanger for cooling as described in any one of claims 1 to 11, wherein the heat passage members for cooling are arranged in parallel at least in part, and the orientation rate of the heat conductive filler in the heat transfer direction in the heat transfer elastomer arranged between adjacent heat passage members for cooling is lower than the orientation rate of the heat conductive filler in the heat transfer direction in the heat transfer elastomer arranged between the opposing heat passage members for cooling and the cooling surface.

13. A heat exchanger for cooling according to any one of claims 1 to 12, wherein the heat transfer elastic body is a foam.

14. A method for manufacturing a cooling heat exchanger for cooling an object to be cooled, comprising: a preparation step for preparing a heat passage member for cooling; and a molding step for insert molding a heat transfer elastomer having a cooling surface to be superimposed on the object to be cooled so that it is in intimate contact with the surface of the heat passage member for cooling, by applying a magnetic field between the heat passage member for cooling and the cooling surface in the molding step, thereby orienting the heat transfer filler in the opposing direction between the heat passage member for cooling and the cooling surface.

15. A method for manufacturing a cooling heat exchanger for cooling an object to be cooled, comprising: a preparation step of preparing a heat passage member for cooling; and a molding step of filling a molding material in which a large number of heat conductive fillers made of a magnetic material are mixed into an elastic base material into a cavity of a molding die in which the heat passage member for cooling is set, and insert molding a heat transfer elastomer having a cooling surface to be superimposed on the object to be cooled so that it is in close contact with the surface of the heat passage member for cooling, wherein in the molding step, a magnetic field inclined with respect to the opposing direction of the heat passage member for cooling and the cooling surface is applied to the heat conductive filler, thereby orienting the large number of heat conductive fillers in a direction inclined with respect to the opposing direction of the heat passage member for cooling and the cooling surface.

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