JP7441343B2 - Heat exchanger - Google Patents

Description

The present invention relates to a heat exchanger manufactured using a laminate material in which a resin layer is laminated on a metal foil layer.

As electronic devices such as smartphones and personal computers become smaller and more sophisticated, measures to prevent heat generation around the CPU of electronic devices have become important. Some models incorporate water-cooled coolers or heat pipes to reduce the heat load on electronic components such as the CPU. Many techniques have been proposed in the past to reduce the amount of heat generated and prevent heat from being trapped inside the housing, thereby avoiding the adverse effects of heat.

Furthermore, battery modules installed in electric vehicles and hybrid vehicles continuously perform large-capacity charging or discharging, which increases the heat generated by the battery pack. For this reason, techniques have been proposed for battery modules as well, similar to the above-mentioned electronic devices, to incorporate water-cooled coolers and heat pipes to avoid the adverse effects of heat.

Furthermore, measures have been proposed for power modules made of silicon carbide (SiC) and the like to prevent heat generation, such as installing a cooling plate or heat sink.

By the way, electronic devices such as the smartphones and personal computers mentioned above have thin casings, and many electronic components and coolers are built into the limited space within the thin casings, so the coolers themselves are also thin. It will be done.

Conventionally, thin coolers such as heat pipes that are built into small electronic devices have generally been made by machining metals with high heat conductivity, such as aluminum, and then joining multiple metal parts together by brazing or diffusion bonding. (Patent Documents 1 to 3, etc.).

However, in the conventional coolers for small electronic devices mentioned above, each component is manufactured by plastic processing such as casting or forging, or metal processing (machining) such as removal processing such as cutting, which is troublesome and has limitations. In particular, there are limits to thinning, and it is difficult to make the thickness any thinner than the current one.

Furthermore, the above-mentioned conventional coolers are difficult to manufacture because they must be manufactured using metal processing (metal-to-metal joining) such as brazing and diffusion bonding, which are highly difficult when joining each component. Not only that, but production efficiency decreases and costs increase.

JP 2015-59693 Publication Japanese Patent Application Publication No. 2015-141002 Japanese Patent Application Publication No. 2016-189415

Under these circumstances, the applicant of the present invention is conducting research on a technique for using a laminate material in which a resin layer is laminated on a metal foil layer as an exterior body of a heat exchanger.

However, when using laminate materials for the exterior body of equipment such as heat exchangers, there is a possibility that the heat exchange medium such as cooling liquid filled inside the exterior body may leak out, so it is necessary to reliably prevent this leakage. We are currently working on the development of technology that can do this.

This invention has been made in view of the above-mentioned problems, and aims to provide a heat exchanger that can be made thinner, can be easily and efficiently manufactured, can reduce costs, and can reliably prevent liquid leakage. purpose.

In order to solve the above problems, the present invention includes the following means.

[1] An exterior body through which a heat exchange medium flows, and an inner fin that has an uneven shape and is housed in the exterior body with a part of the fin in contact with the inner peripheral surface of the exterior body. A heat exchanger,
The exterior body is composed of a laminate material in which a resin protective layer and a resin sealant layer are laminated in this order on the inner surface side of a metal foil layer,
The inner fin is made of a laminate material in which resin coating layers are laminated on both sides of a metal foil layer,
A heat exchanger characterized in that the protective layer in the exterior body is configured to remain in the missing portion of the sealant layer to prevent exposure of the metal foil layer.

[2] The heat exchanger according to item 1, wherein the protective layer of the exterior body is made of a resin having a higher melting point than the sealant layer.

[3] The heat exchanger according to the above item 1 or 2, wherein the protective layer of the exterior body is constituted by a resin film or sheet laminated on the metal foil layer and the sealant layer.

[4] The heat exchanger according to any one of items 1 to 3 above, wherein the laminate material constituting the exterior body includes a resin heat-resistant layer laminated on the outer surface side of the metal foil layer.

[5] The heat exchanger according to any one of items 1 to 4 above, wherein the sealant layer of the exterior body and the coating layer of the inner fin are made of the same type of heat-sealing resin.

[6] The heating device according to any one of the preceding clauses 1 to 5, wherein the edge of the inner fin is provided with a resin coating part for preventing the metal foil layer from being exposed from the edge. exchanger.

[7] An extension portion is formed such that the edge of the coating layer on both sides of the inner fin extends in the edge extension direction, so that the edge of the metal foil layer extends from each side of the coating layer on both sides. 7. The heat exchanger according to any one of the preceding items 1 to 6, which is disposed so as to be recessed inward from the edge of the extension.

[8] Item 1 above, comprising a joint member having a pipe portion that is arranged to penetrate through an entrance/exit provided in the exterior body, and a mounting portion that is connected to the pipe portion and is housed inside the exterior body. The heat exchanger according to any one of items 1 to 7.

[9] The heat exchanger according to item 9, wherein at least the skin portion of the attachment portion of the joint member is made of the same type of heat-sealing resin as the sealant layer of the exterior body.

According to the heat exchanger of invention [1], since the protective layer is provided between the metal foil layer and the sealant layer in the laminate material for the exterior body, there is no possibility that the sealant layer may be missing due to excessive thermal adhesion, etc. However, the protective layer remains in the missing portion and covers the metal foil layer, thereby preventing the metal foil layer from being exposed. Therefore, the metal foil layer is not inadvertently exposed to the heat exchange medium, and it is possible to prevent liquid leakage due to corrosion of the metal foil layer. Furthermore, in the heat exchanger of the present invention, since the exterior body is manufactured using a laminate material, there is no need to use troublesome metal processing, and it can be manufactured easily and efficiently, reducing costs. It can also be made thinner.

According to the heat exchanger of inventions [2] and [3], the above effects can be obtained more reliably.

According to the heat exchanger of invention [4], corrosion of the metal foil layer due to external factors such as dew condensation can also be prevented.

According to the heat exchanger of invention [5], it is possible to thermally bond the sealant layer of the exterior body and the coating layer of the inner fin with sufficient attachment strength.

According to the heat exchanger of inventions [6] and [7], it is possible to prevent the edges of the metal foil layer in the inner fin from being exposed, and it is possible to avoid adverse effects on the exterior body due to the metal foil layer of the inner fin. .

According to the heat exchanger of inventions [8] and [9], the heat exchange medium can be smoothly flowed in and out of the exterior body through the pipe portion, improving heat exchange performance, and the mounting portion can be inserted into the exterior body. It can be thermally bonded to the surrounding surface in a stable state with sufficient mounting strength, and the sealing performance around the entrance and exit can be further improved.

FIG. 1 is a perspective view showing a heat exchanger according to an embodiment of the invention. FIG. 2 is an exploded perspective view of the heat exchanger of the embodiment. FIG. 3 is a partially cutaway perspective view of the heat exchanger of the embodiment. FIG. 4 is an enlarged cross-sectional view of a portion surrounded by a dashed line S1 in FIG. FIG. 5 is an enlarged cross-sectional view of a portion surrounded by a dashed line S2 in FIG. FIG. 6 is an enlarged cutaway perspective view showing the area around the contact portion between the edge portion of the inner fin and the bottom surface of the tray member in the heat exchanger of this embodiment. FIG. 7 is a sectional view taken along line DD in FIG. FIG. 8 is a diagram showing a laminate material for an inner fin according to a first modified example of the present invention, in which FIG. 8(a) is a plan view and FIG. 8(b) is a sectional view of the end portion. FIG. 9 is a sectional view of an end portion of a laminate material for an inner fin according to a second modification of the present invention. FIG. 10 is an enlarged sectional view showing a contact portion between an inner fin and the bottom surface of a tray member in a heat exchanger that deviates from the gist of the present invention, and is a sectional view of a portion corresponding to FIG. 5. FIG. 11 is a perspective view for explaining a corroded portion of a tray member in a heat exchanger that deviates from the gist of the present invention.

FIG. 1 is a perspective view showing a heat exchanger according to an embodiment of the present invention, FIG. 2 is an exploded perspective view showing the heat exchanger according to the embodiment, and FIG. 3 is a partially cutaway view of the heat exchanger according to the embodiment. FIG.

As shown in these figures, the heat exchanger of this embodiment is used as a heat transfer panel, a heat transfer tube, etc., and includes an exterior body 1 as a casing and inner fins housed inside the exterior body 1. (internal fins) 2 and a pair of joint members 3, 3 housed within both ends of the exterior body 1.

The exterior body 1 includes a tray member 10 that is rectangular in plan view and a cover member 15 that is rectangular in plan view.

In the tray member 10, the intermediate region excluding the outer peripheral edge is formed with a recess downward using a cold forming method such as deep drawing molding or extrusion molding, so that a recess 11 is formed and an opening of the recess 11 is formed. A flange portion 12 is integrally formed around the edge so as to protrude outward.

The tray member 10 and the cover member 15 are made of a laminate material L1 that is a flexible laminate sheet.

As shown in FIG. 4, the laminate material L1 for the exterior body is made of a metal foil layer 51 made of metal foil, and a resin film or resin sheet laminated on one surface (inner surface) of the metal foil layer 51 via an adhesive. a protective layer 55, a sealant layer 52 made of a resin film or resin sheet laminated on one surface (inner surface) of the protective layer 55 via an adhesive, and a sealant layer 52 laminated on the other surface (outer surface) of the metal foil layer 51 via an adhesive. A heat-resistant layer 53 made of a resin film or a resin sheet is provided. Note that in this embodiment, the term "foil" is used to include films, thin plates, and sheets.

As the metal foil layer 51 in the laminate material L1, 1000 series, 3000 series, 5000 series, 8000 series aluminum foil, copper foil, stainless steel foil, nickel foil, titanium foil, etc. can be suitably used. In this embodiment, the terms "aluminum," "copper," "nickel," and "titanium" are used to include alloys thereof.

The metal foil layer 51 is also referred to as a heat transfer layer or a heat collecting layer, and preferably has a thickness of 8 μm to 300 μm, more preferably 100 μm or less.

Moreover, by subjecting the metal foil layer 51 to surface treatment such as chemical conversion treatment, it is possible to further improve durability by preventing corrosion of the metal foil layer 51 and improving adhesiveness with resin.

For example, the chemical conversion treatment is performed as follows. That is, the surface of the metal foil that has been subjected to the degreasing treatment is coated with an aqueous solution of any one of the following 1) to 3) and then dried to perform the chemical conversion treatment.

1) An aqueous solution of a mixture containing phosphoric acid, chromic acid, and at least one compound selected from the group consisting of metal salts of fluoride and non-metal salts of fluoride.

2) Phosphoric acid, at least one resin selected from the group consisting of acrylic resins, chitosan derivative resins, and phenolic resins, and at least one compound selected from the group consisting of chromic acid and chromium (III) salts. , an aqueous solution of a mixture containing.

3) Phosphoric acid, at least one resin selected from the group consisting of acrylic resins, chitosan derivative resins, and phenolic resins, and at least one compound selected from the group consisting of chromic acid and chromium (III) salts. , at least one compound selected from the group consisting of metal salts of fluoride and non-metal salts of fluoride.

The amount of chromium deposited (per one side) in the chemical conversion film is preferably set to 0.1 mg/m ² to 50 mg/m ² , and more preferably 2 mg/m ² to 20 mg/m ² .

Regarding this surface treatment, the same applies to the metal foil layer 61 of the fin laminate material L2 described later.

As will be described later, when the sealant layer 52 is partially broken or melted and the sealant layer 52 is missing, the protective layer 55 remains in the missing part and protects the metal foil layer 51. By maintaining the coated state, the metal foil layer 51 is prevented from being exposed, thereby preventing corrosion of the metal foil layer 51. Therefore, it is preferable that the protective layer 55 be made of a resin having stronger strength and a higher melting point than the sealant layer 52.

As the protective layer 55, for example, a polyethylene terephthalate resin film, a polyamide resin film, a polyethylene naphthalate resin film, a polypropylene resin film, etc. can be suitably used.

Further, as the protective layer 55, as described above, it is preferable to use a resin having a higher melting point than the sealant layer 52, more preferably a resin having a melting point higher than 20°C. That is, when a resin with a high melting point is used as the protective layer 55, it is possible to prevent the protective layer 55 from melting when the heat-sealing layer 62 of the inner fin 2 is heat-sealed to the sealant layer 52 of the exterior body 1. , the metal foil layer 51 can be reliably protected.

Further, the protective layer 55 can be formed by dry lamination, which is formed in a dry state.

As the protective layer 55, it is preferable to use a stretched film. Further, as the protective layer 55, it is preferable to use one having a water vapor permeability of 50 g/(m ² ·24 h) or less according to JIS K7129.

Further, it is preferable to use a protective layer 55 having a thickness of 12 μm to 50 μm.

As the sealant layer 52, a film or sheet made of polyolefin (unoriented polypropylene (CPP), polyethylene (LDPE, LLDPE)) or modified resin thereof, fluorine resin, polyester resin, vinyl chloride resin, etc. is preferably used. be able to.

This sealant layer 52 can preferably have a thickness of 12 μm to 50 μm.

As the heat-resistant layer 53, a film or sheet made of polyethylene terephthalate resin, polyamide resin, polyethylene naphthalate resin, polypropylene resin, or the like can be suitably used.

In this embodiment, the basic structure is that the film or sheet as the heat-resistant layer 53 is adhered to the metal foil layer 51 via an adhesive, but if necessary, the heat-resistant layer may be formed without using an adhesive. The heat-resistant layer 53 may be laminated (film-formed) by coating the metal foil layer 51 with a resin.

The heat-resistant layer 53 is intended to avoid condensation on the metal foil layer 51 and adverse effects from corrosive components in the atmosphere, so if the metal foil layer 51 is protected, a heat-fusible resin is used. You can also do that.

Furthermore, since the heat-resistant layer 53 is in direct contact with a member to be cooled (a member to be heat exchanged) such as a battery, it is preferably thinner in order to improve heat exchange performance. Specifically, it is preferable to use a heat-resistant layer 53 having a thickness of 20 μm to 5000 μm.

In addition, as an adhesive layer for adhering the metal foil layer 51, the protective layer 55, the sealant layer 52, and the heat-resistant layer 53 that constitute the exterior body laminate material L1, a urethane adhesive with a thickness of 1 μm to 5 μm, Epoxy adhesives, olefin adhesives, and the like can be suitably used.

The tray member 10 and cover member 15 of the exterior body 1 are configured by the laminate material L1 having the above configuration. Then, as will be described later, the cover member 15 is arranged to close the recess opening of the tray member 10, and the outer peripheral edge of the cover member 15 is joined and integrated with the flange portion 12 of the tray member 10, thereby forming an exterior body. 1 is formed.

In this embodiment, entrances and exits 16 are formed at both ends of the cover member 15, respectively.

As shown in FIGS. 1 to 3, the inner fin 2 accommodated in the hollow portion (recess 11) of the exterior body 1 is made of a laminate material L2 that is a flexible laminate sheet. As shown in FIG. 4, the laminate material L2 includes a metal foil layer 61 made of metal foil, and coating layers 62, 62 made of resin films or resin sheets laminated on both sides of the metal foil layer 61 via an adhesive. It is equipped with

The metal foil layer 61 of the laminate material L2 for the inner fin includes copper foil, aluminum foil, stainless steel foil, nickel foil, plated copper foil, and nickel-copper clad metal in which nickel foil and copper foil are clad. Those selected from among them can be suitably used.

The metal foil layer 61 preferably has a thickness of 8 μm to 300 μm, more preferably 100 μm or less.

Further, as described above, the performance can be further improved by subjecting the metal foil layer 61 to the same surface treatment as the metal foil layer 51 of the exterior body 1.

As the covering layer 62, a heat-fusible film or sheet made of polyolefin (unoriented polypropylene (CPP), polyethylene (LDPE, LLDPE)), fluororesin, polyester resin, vinyl chloride resin, etc. is preferably used. be able to.

In addition, as the adhesive layer for adhering the metal foil layer 61 and the coating layers 62, 62 constituting the inner fin laminate material L2, urethane adhesive or epoxy adhesive with a thickness of 1 μm to 5 μm is used as described above. Adhesives, olefin adhesives, etc. can be suitably used.

In this embodiment, the resin layers 62, 62 on both sides of the laminate material L2 constituting the inner fin 2 are made of the same type of thermal adhesive resin (same thermal adhesive resin) as the sealant layer 53 of the laminate material L1 constituting the exterior body 1. (including adhesive resin, the same applies hereinafter).

The inner fin 2 is formed by processing the sheet material made of the laminate material L2 to form irregularities.

The uneven processing may be any process as long as it can provide three-dimensional unevenness to the laminate material L2. A processing method that can provide unevenness can be suitably used.

Corrugating is, for example, forming a corrugated three-dimensional shape in one direction by passing a workpiece such as laminate material L2 between a pair of rolls with axial grooves formed on the outer periphery at equal intervals in the circumferential direction. This is a processing method that

Pleating is a processing method in which a workpiece such as the laminate material L2 is alternately folded front and back to form folds (pleats).

Embossing is a processing method of imparting unevenness to a work such as the laminate material L2 using an embossing roll having an uneven pattern formed on the outer peripheral surface. In this embodiment, the uneven pattern formed on the embossing roll is not particularly limited, and uneven patterns such as a diamond pattern, a silky texture, a cloth texture, a satin texture, a polka dot shape, a blind pattern, a striped pattern, etc. Can be adopted.

In this embodiment, the inner fin 2 is manufactured by corrugating a sheet material made of the laminate material L2 to form a wavy uneven shape.

This inner fin 2 is accommodated in the middle part of the recess 11 of the tray member 10 excluding both ends. The housed inner fins 2 are arranged so that their ridge and valley directions (left and right directions when viewed from the page of FIG. 2) match the length direction of the tray member 10 (left and right directions when viewed from the page of FIG. 2). It is located in As a result, the tunnel portions and groove portions formed along the mountain and valley portions of the inner fin 2 are arranged along the length direction of the tray member 10, and heat is exchanged through the tunnel portions and groove portions. It is configured so that the medium can smoothly flow from one end of the exterior body 1 in the length direction to the other end.

As shown in FIG. 2, a pair of joint members 3, 3 disposed within both ends of the exterior body 1 are made of a molded article of hard synthetic resin.

The joint member 3 includes a box-shaped mounting box portion 31 having an opening 32 on one side, and a pipe portion 33 provided on the upper wall of the mounting box portions 31, 31. The pipe portion 33 communicates with the inside of the mounting box portion 31, and is configured so that a heat exchange medium can pass between the inside of the pipe portion 33 and the inside of the mounting box portion 31. In this embodiment, the mounting box portion 31 of the joint member 3 constitutes a mounting portion.

In this embodiment, as the material for the joint member 3, for example, polyolefin resins such as polyethylene and polypropylene, modified resins thereof, and heat-sealing resins such as fluororesins, polyester resins, and vinyl chloride resins can be suitably used. In particular, it is preferable to use a heat-sealing resin such as high-density polyethylene (HDPE). In this embodiment, at least the outer surface (skin part) of the joint member 3 is made of the same or the same heat-sealing resin as the sealant layer 52 of the laminate material L1 that constitutes the exterior body.

The mounting box portion 31 of the joint member 3 is arranged on both sides of the inner fin 2 in the recess 11 of the tray member 10. In this case, the pipe portion 33 of the joint member 3 is disposed upward, and the opening 32 of the mounting box portion 31 is disposed inward, that is, facing the inner fin 2 side.

In this way, the inner fin 2 and the joint members 3, 3 are accommodated in the tray member 10, and the cover member 15 is placed on the tray member 10 so as to close the opening thereof. In this case, the upwardly directed pipe portions 33, 33 of the joint members 3, 3 are inserted into the entrance/exit 16 of the cover member 15.

By heating the heat transfer panel P temporarily assembled in this way under reduced pressure, the contacting members are thermally fused and integrated.

That is, the sealant layer 52 on the flange portion 12 of the tray member 10 and the sealant layer 52 on the outer peripheral edge portion of the cover member 15 are joined and integrated by thermal adhesion (thermal fusion) to seal in a liquid-tight or air-tight state. Here, since the sealant layer 52 of the tray member 10 and the sealant layer 52 of the cover member 15 are made of the same type of heat-sealing resin, both can be reliably fixed with sufficient attachment strength.

Furthermore, the coating layers 62, 62 at the top and bottom of the inner fin 2 are joined and integrated with the bottom wall of the tray member 10 and the sealant layer 52 of the cover member 15 by thermal bonding (thermal fusion). Here, since the coating layers 62, 62 of the inner fin 21 and the sealant layer 52 of the tray member 10 and cover member 15 are made of the same type of heat-sealing resin, both can be reliably fixed with sufficient mounting strength. be able to.

Further, the outer circumferential surfaces of the mounting box parts 31, 31 of the joint members 3, 3 and the sealant layers 52, 52 of the tray member 10 and cover member 15 are joined and integrated by thermal bonding (thermal fusion). Here, since the joint members 3, 3 and the sealant layer 52 of the tray member 10 and cover member 15 are made of the same type of resin, both can be reliably fixed with sufficient mounting strength. Therefore, the peripheral parts of the pipe parts 33, 33 of the joint members 3, 3 are bonded to the peripheral parts of the entrances and exits 16, 16 of the cover member 15 in a liquid-tight or airtight state, and liquid leakage from the entrances and exits 16, 16 occurs. problems can be reliably prevented.

The thus assembled heat exchanger is arranged such that the pipe portions 33, 33 of the joint members 3, 3 protrude upward from the upper wall (cover member 15) at both ends of the exterior body 1.

The heat exchanger having the above configuration is used as a cooler (cooling device) that cools a battery or the like as a member to be cooled (a member to be heat exchanged). That is, one pipe section 33 of the heat exchanger is connected with an inflow pipe for inflowing a cooling liquid (cooling water, antifreeze, etc.) as a heat exchange medium (refrigerant), and the other pipe section 33 is connected with a cooling liquid (cooling water, antifreeze, etc.). An outflow pipe for outflowing the liquid is connected. Furthermore, a battery as a member to be cooled is placed in contact with the upper and lower walls of the exterior body 1 of the heat exchanger. In this state, the cooling liquid flows into the exterior body 1 from one pipe part 33 via one joint member 3, and the cooling liquid is circulated through the inner fin 2 part to open the other joint member 3. The water flows out from the other pipe section 33 through the pipe section 33. By circulating the coolant through the exterior body 1 in this manner, heat is exchanged between the coolant and the battery via the inner fins 2 and the upper and lower walls of the exterior body 1, thereby cooling the battery. .

The heat exchanger of this embodiment is characterized in that a protective layer 55 is provided between the metal foil layer 51 and the sealant layer 52 in the laminate material L1 constituting the exterior body 1. Due to its unique structure, it has excellent corrosion resistance. The mechanism will be explained in detail below.

According to research conducted by the present applicant, it has been found that the portion of the metal foil layer 51 of the exterior body 1 that is likely to be corroded is the portion where it contacts the edge portion of the inner fin 2. For example, the part surrounded by the dashed line S2 in FIG. Corrosion is likely to occur at the contact portion with the edge portion of the inner fin 2, but corrosion is less likely to occur at portions other than the edge portion of the inner fin 2.

That is, as shown in FIG. 10, when the exterior body 1 is made of a laminate material L3 that does not have a protective layer, that is, a laminate material L3 in which a sealant layer 52 is adhered to the inner surface of a metal foil layer 51, Even if excessive heat or pressure is applied at the time of attachment, the resin constituting the molten sealant layer 52 and coating layer 62 will be extruded to cover the metal foil layer 51 in areas other than the edge portions of the inner fin 2. The metal foil layer 51 is not exposed. Therefore, the metal foil layer 51 is not exposed to the cooling liquid, and corrosion in the metal foil layer 51 is prevented. Therefore, no pinholes occur in the metal foil layer 51, and no liquid leakage occurs.

In particular, in the heat exchanger of this embodiment, as shown in FIG. Since the protective layer 55 remains without being melted, exposure of the metal foil layers 51 and 61 can be more reliably prevented, and corrosion and liquid leakage can be more reliably prevented from occurring.

However, as described above, it has been found that corrosion is likely to occur at the edge portions of the inner fins 2 where they come into contact with the exterior body 1. For example, FIG. 6 is an enlarged cutaway perspective view showing the contact portion between the edge portion 21 of the inner fin 2 and the bottom surface of the recess of the exterior body 1 (tray member 10), and the portion indicated by the dashed line S3 in FIG. FIG. 7 is a cross-sectional view taken along the line DD in FIG. 6. As shown in these figures, when the exterior body 1 and the inner fins 2 are thermally bonded under reduced pressure, the exterior body 1 contracts. 7, the lower wall of the exterior body 1 is bent so that the outer side of the contact point with the edge portion 21 (the right side in FIG. 7) is lifted upward, as shown by the imaginary line in FIG. transform. During this deformation, stress is concentrated at the contact point with the edge portion 21 on the lower wall of the outer fin 2, and the edge of the metal foil layer 61 of the inner fin 2 causes the melted resin (sealant layer 52) of the outer fin 1 to As a result of extrusion, an interrupted portion (missing portion) of the sealant layer 52 occurs. Here, if the exterior body 1 is made of a laminate material (see laminate material L3 in FIG. 10) in which a protective layer is not provided between the sealant layer 52 and the metal foil layer 51, the sealant layer The metal foil layer 51 is exposed at the missing portion 52, and the exposed portion is exposed to the cooling liquid in the exterior body 1, causing corrosion to occur in the metal foil layer 51. In this case, pinholes are formed in the metal foil layer 51 due to the corrosion, resulting in liquid leakage.

For reference, when the exterior body 1 made of the laminate material L3 without a protective layer and the inner fins 2 are thermally bonded under reduced pressure, the inner fins 2 on the bottom wall of the concave portion of the exterior body 1 are bonded together under reduced pressure. A corroded portion 4 was confirmed in the metal foil layer 51 of the exterior body 1 at the contact portion with the edge portion 21 .

In contrast, in the heat exchanger of this embodiment, a protective layer 55 with high strength and a high melting point is provided between the metal foil layer 51 and the sealant layer 52 of the exterior body 1. Even if the melted sealant layer 52 of the exterior body 1 is extruded by the edge of the metal foil layer 61 of the inner fin 2 after being thermally bonded, and a defect occurs in the sealant layer 52, in the defect, The metal foil layer 51 is kept covered by the protective layer 55. Therefore, the metal foil layer 51 can be prevented from being corroded, and the occurrence of pinholes and liquid leakage can be reliably prevented.

In this embodiment, if the edge of the metal foil layer 61 at the edge portion 21 of the inner fin 2 is not exposed to the outside, there will be an adverse effect on the exterior body 1 and the metal foil layer 61 itself of the inner fin 2 will be damaged. Corrosion can be prevented. For example, as shown in FIG. 8(a), as the laminate material L2 constituting the inner fin 2, the resin film for the coating layers 62 on both sides is one size larger than the metal foil for the metal foil layer 61. Adopt something. As a result, as shown in FIG. 8(b), at the edge of the laminate material L2 for the inner fin 2, the coating layers 62, 62 on both sides are extended, and the metal foil layer is further extended than the edge of the extended portion 66. The end edge of 61 is recessed inward. If the inner fins 2 are manufactured by processing such a laminate material L2 into irregularities, the edges of the metal foil layer 61 of the inner fins 2 will not be exposed, so that adverse effects on the exterior body 1 can be avoided. .

Furthermore, as shown in FIG. 9, as the laminate material L2 for the inner fin 2, the edge is coated with resin to form a coating part 65, and the edge of the metal foil layer 61 is covered with the coating part 65. I'll keep it. Also in the inner fin 2 made of the laminate material L2, the edges of the metal foil layer 61 are not exposed, so that adverse effects on the exterior body 1 can be avoided.

Further, as shown in FIGS. 8(a) and 8(b), the coating layers 62, 62 may be formed into extensions 66 at the edges of the inner fins 2, or the edges of the coating layers 62, 62 may be formed as shown in FIG. When the coating part 65 is formed in between, the coating layer extension part 66 and the coating part 65 function as a cushioning material for the inner surface of the exterior body 1, and when the sealant layer 52 of the exterior body 1 melts excessively, Since it functions as a replenishing material, it is possible to prevent the metal foil layer 51 of the exterior body 1 from being exposed from this point of view, and the occurrence of corrosion and pinholes can be more reliably prevented, thereby further improving durability. I can do it.

As described above, according to the heat exchanger of the present embodiment, since the protective layer 55 is provided between the metal foil layer 51 and the sealant layer 52 in the laminate material L1 constituting the exterior body 1, the sealant layer 52 Even if the protective layer 55 is missing due to excessive thermal adhesion or the like, the protective layer 55 remains in the missing part and covers the metal foil layer 51, thereby preventing the metal foil layer 55 from being exposed. Therefore, the metal foil layer 55 is not inadvertently exposed to the cooling liquid, and corrosion and pinholes in the metal foil layer 55 can be prevented, thereby providing a high-quality heat exchanger free from problems such as liquid leakage. can do.

Furthermore, according to the heat exchanger of this embodiment, since the exterior body 1 is manufactured using the laminate materials L1 and L2, there is no need to use troublesome metal processing, and it can be manufactured efficiently and easily, reducing costs. In addition, since it is manufactured by joining the exterior body 1 and the inner fin 2, which are the laminate materials L1 and L2, it is possible to sufficiently reduce the thickness.

Furthermore, in the heat exchanger of this embodiment, the sealant layer 52 of the exterior body 1 and the coating layer 62 of the inner fin 2 that is heat-sealed to the sealant layer 52 are made of the same type of heat-sealing resin. , the two layers 52 and 62 can be thermally bonded with sufficient attachment strength, peeling etc. can be prevented and sufficient durability can be obtained. Furthermore, since the materials are thermally bonded, the adhesiveness is good and excessive thermal bonding can be effectively prevented. From this point of view, the metal foil layers 51 and 61 can be prevented from being exposed, and the metal foil layers can be bonded more reliably. Corrosion of 51 and 61 can be prevented.

Furthermore, in the heat exchanger of this embodiment, since the heat-resistant layer 53 is laminated on the outer surface of the exterior body 1, corrosion of the metal foil layer 51 due to external factors such as dew condensation can be more reliably prevented. Durability can be further improved.

Furthermore, in the heat exchanger of this embodiment, since the pipe portions 33 of the joint members 3 provided at both ends of the exterior body 1 are arranged to penetrate through the entrance/exit port 16, the exterior body The cooling liquid can flow in and out smoothly and stably, and the cooling performance (heat exchange performance) can be improved.

Furthermore, since the mounting box portion 31 of the joint member 3 housed inside the exterior body 1 is made of the same type of heat-sealing resin as the sealant layer 52 of the exterior body 1, the mounting box portion 31 of the exterior body 1 is It can be thermally bonded to the inner circumferential surface with sufficient mounting strength, further improving the sealing performance around the entrance and exit, and reliably preventing liquid leakage from around the entrance and exit.

In the above embodiment, the case where the heat exchanger is used as a cooler (cooling device) by circulating a cooling heat medium (refrigerant) inside the heat exchanger has been described as an example, but the present invention is not limited thereto. It is also possible to use the heat exchanger as a heater (heating device) or a heat generator (heat generating device) by circulating a heating medium (thermal medium) inside the heat exchanger.

Further, in the above embodiment, when manufacturing the exterior body 1, the three-dimensionally molded tray member 10 and the sheet-like cover member 15 are pasted together, but in the present invention, the three-dimensionally molded member (Laminate materials) You can also paste them together. Furthermore, the constituent members of the exterior body 1 do not necessarily need to be three-dimensionally molded. For example, if three-dimensional molding is not performed, a bag-shaped exterior body made of laminate material may be manufactured by bonding the outer peripheral edges of two sheets of laminate material to each other by heat fusion, etc. .

Further, in the above embodiment, the case where the exterior body 1 is manufactured using two laminate materials has been described as an example, but the present invention is not limited to this. A bag-shaped exterior body may be manufactured by bonding the outer peripheral edge portions of the overlapping laminate materials, excluding the folded portions, by heat fusion or the like. Needless to say, in the present invention, the exterior body may be manufactured using three or more laminate materials.

Further, in the above embodiment, the laminate materials L1 and L2 have a three-layer or four-layer structure, but the present invention is not limited to this. Also good. In short, it is sufficient that the protective layer 55 is provided between the metal foil layer 51 and the sealant layer 52 in the laminate material for the exterior body.

Further, in the above embodiment, the case where the heat exchanger of the present invention is used as a cooler for a battery pack for an automobile etc. has been described as an example, but in the present invention, a heat exchanger other than a cooler for a battery pack is used. It can also be applied to For example, heat exchangers for heating automobile battery packs, heat for cooling power semiconductor elements (power modules) for controlling the main power of power-driven equipment such as automobile electric motors, industrial machinery, home appliances, and information terminals. Exchangers, heat exchangers for cooling the CPU (central processing unit) of personal computers, heat exchangers for cooling/heating storage batteries for household or commercial use, heat exchangers for cooling the battery packs (battery modules) of personal computers. It can also be used as a heat exchanger for cooling LCD TVs, organic EL TVs, and plasma TV displays, floor heating equipment, and snow melting equipment for roofs, walkways, roads, etc. in cold regions. can.

<Example>
Based on the heat exchanger of the above embodiment shown in FIGS. 1 to 3, a heat exchanger of an example was manufactured as follows.

1. Preparation of laminate material L1 (LLDPE40/adhesive/PET25/adhesive/AL120/adhesive/PET25) for exterior body 1 (1) Chromate on JIS H4160 A8021 aluminum foil (thickness 120 μm) as a metal foil layer Treatment is carried out to coat both sides with a base layer (chromium coverage 10 g/m ² per side).

(2) A PET film (thickness: 25 μm) is laminated as a heat-resistant layer 53 on one surface (outer surface) of the aluminum foil via a urethane adhesive (thickness: 2 μm).

(3) A biaxially oriented polyethylene terephthalate (PET) film (25 μm thick) as a protective layer 55 is laminated on the other surface (inner surface) of the aluminum foil via a urethane adhesive (2 μm thick).

(4) LLDPE (40 μm thick) as the sealant layer 52 is laminated on the other surface (inner surface) of the biaxially stretched PET film as the protective layer 55 via a urethane adhesive (2 μm thick).

2. Preparation of laminate material L2 (LLDPE40/adhesive/AL120/adhesive/LLDPE40) for fin 2 (1) Perform chromate treatment on JIS H4160 A8021 aluminum foil (thickness 120 μm) and coat both sides with a base layer. (The amount of chromium deposited is 10 g/m ² per side).

(2) LLDPE (40 μm thick) is laminated as coating layers 62, 62 on one side and the other side of the aluminum foil via a urethane adhesive (2 μm thick), respectively.

3. Preparation of Joint Member 3 (HDPE) A joint member 3 made of HDPE was prepared, in which a pipe portion 33 was integrally molded into a mounting box portion 31 measuring 100 mm long x 12 mm wide x 3 mm high. The pipe portion 33 has an inner diameter of 10 mm, an outer diameter of 12 mm, and a length of 3 mm.

4. Preparation of heat exchanger components (1) Preparation of tray member 10 A sheet material obtained by cutting the laminate material L1 for the exterior material 1 into 230 mm in length x 160 mm in width is wrapped in Al foil (metal foil layer 51). On the other hand, the concave portion 11 was formed by embossing to a depth of 3 mm using a mold measuring 169 mm in length x 104 mm in width and with a corner R4 so that the PET film (heat-resistant layer 53) side was the convex side (outside). Furthermore, the periphery of the flange portion 12 formed at the opening periphery of the recessed portion 11 was cut to have a width of 5 mm, thereby producing the tray member 10.

(2) Production of the cover member 15 A sheet material obtained by cutting the laminate material L1 for the exterior body 1 into a size of 180 mm in length x 115 mm in width, and the joint members 3, The cover member 15 was manufactured by forming openings 16, 16 for inserting the pipe portions 33, 33 of No. 3.

(3) Fabrication of inner fin 2 The sheet material obtained by cutting the laminate material L2 for the inner fin 2 into 145 mm long x 210 mm wide is corrugated so that it is folded back alternately at a width (pitch) of 3.5 mm in the horizontal direction. By processing, a meander-shaped inner fin 21 with each peak having a height of 3 mm was produced.

5. Assembling and Joining Components (1) The joint members 3, 3 are housed at both ends of the recess 11 of the tray member 10 in the vertical direction (lengthwise direction), with the pipe portions 33, 33 facing upward. Further, the inner fin 2 was accommodated between both the joint members 3 in the recess 11 of the tray member 10. Note that the openings 32, 32 of the joint members 3, 3 were arranged inward so as to face the ends of the inner fins 2.

(2) Place the cover member 15 on the flange portion 12 of the tray member 10 with its inner side (the side where the biaxially stretched PET film as the protective layer 55 is present) facing down so as to cover the recess 11 of the tray member 10 from above. It was placed in At this time, the upwardly directed pipe parts 33, 33 of the joint members 3, 3 in the tray member 10 were inserted through the entrances and exits 16, 16 of the cover member 15, and were arranged so as to protrude above the cover member 15. In this way, a heat exchanger temporary assembly in a non-bonded state was produced, and the flange portion 12 of the tray member 10 was set at 200° C. while the heat exchanger temporary assembly was depressurized to 200 mmHg in a chamber-type pressure reducing machine. The heat exchanger of the example was produced by sealing with a hot plate for 5 seconds and thermally adhering (thermal fusion) the respective parts. By heating under reduced pressure, thermal bonding can be achieved between the tray member 10 and the cover member 15, and between the tray member 10 and cover member 15 and the inner fin 2 and joint members 3, 3 that are in contact with them. can be strongly performed.

<Comparative example>
1. Preparation of laminate material L3 (LLDPE40/adhesive/AL120/adhesive/PET25) for exterior body 1 (1) Perform chromate treatment on JIS H4160 A8021 aluminum foil (thickness 120 μm) as a metal foil layer, and The formation is coated on both sides (chromium coverage 10 g/m ² per side).

(2) A PET film (thickness: 25 μm) is laminated as a heat-resistant layer 53 on one surface (outer surface) of the aluminum foil via a urethane adhesive (thickness: 2 μm).

(3) LLDPE (40 μm thick) as the sealant layer 52 is laminated on the other surface (inner surface) of the aluminum foil via a urethane adhesive (2 μm thick).

2. A heat exchanger of a comparative example was manufactured in the same manner as in the above example except that the exterior body 1 (tray member 10 and cover member 15) was manufactured using the laminate material L3. That is, the heat exchanger of the comparative example is similar to the heat exchanger of the above-mentioned example, except that the protective layer 55 is not provided on the exterior body 1.

<Accelerated test for corrosion resistance>
As a corrosive liquid, an OY liquid (a pH 3 corrosive liquid containing Cl ⁻ : 195 ppm, SO ₄ ²⁻ : 60 ppm, Cu ²⁺ : 1 ppm, and Fe ³⁺ : 30 ppm) was prepared.

The corrosive liquid was introduced into the heat exchangers of Examples and Comparative Examples through one pipe section 33, circulated therein, and circulated so as to flow out from the other pipe section 33. As test conditions during this circulation, the temperature of the corrosive liquid was 60° C., the flow rate was 1 L/min, and the circulation time was 250 hours continuously.

After the test, the external appearance of the heat exchangers of Examples and Comparative Examples was visually observed and evaluated. As a result, the heat exchanger of the example had no liquid leakage and no particular change in appearance. On the other hand, in the heat exchanger of the comparative example, the portions of the bottom surface of the lower wall of the exterior body 1 (the bottom surface of the tray member 10) and the bottom surface of the upper wall (the inner surface of the cover member 15) are in contact with the edges of the inner fins 2. A white corroded area 4 (see FIG. 11) was observed.

As is clear from the test results, the heat exchangers of the examples related to the present invention are found to have excellent corrosion resistance.

The heat exchanger of the present invention can be suitably used as a cooler for power modules and batteries in automobiles, a cooler for stationary batteries, a cooler for supercomputers, and the like.

1: Exterior body 2: Inner fin 3: Joint member 33: Pipe section 51: Metal foil layer 52: Sealant layer 53: Heat resistant layer 55: Protective layer 61: Metal foil layer 62: Covering layer 63: Covering layer 65: Coating section 66: Extension L1: Laminate material for exterior body L2: Laminate material for inner fin

Claims (6)

A heat exchanger comprising an exterior body through which a heat exchange medium flows, and an inner fin that has an uneven shape and is housed in the exterior body with a part of the fin in contact with the inner peripheral surface of the exterior body. And,
The exterior body is composed of a laminate material in which a resin sealant layer is laminated on the inner surface side of a metal foil layer,
The inner fin is made of a laminate material in which resin coating layers are laminated on both sides of a metal foil layer,
A heat exchanger characterized in that a coating portion is provided on an edge of the inner fin to prevent a metal foil layer from being exposed from the edge. A heat exchanger comprising an exterior body through which a heat exchange medium flows, and an inner fin that has an uneven shape and is housed in the exterior body with a part of the fin in contact with the inner peripheral surface of the exterior body. And,
The exterior body is composed of a laminate material in which a resin sealant layer is laminated on the inner surface side of a metal foil layer,
The inner fin is made of a laminate material in which resin coating layers are laminated on both sides of a metal foil layer,
The extension portions are formed such that the edges of the coating layer on both sides of the inner fin extend in the edge extension direction, and the edges of the metal foil layer are aligned with each extension portion of the coating layer on both sides. A heat exchanger characterized in that the heat exchanger is disposed inwardly with respect to an edge. 3. The heat exchanger according to claim 1 , wherein the laminate material constituting the exterior body includes a resin heat-resistant layer laminated on the outer surface side of the metal foil layer. The heat exchanger according to any one of claims 1 to 3, wherein the sealant layer of the exterior body and the coating layer of the inner fin are made of the same type of heat-sealing resin. Claims 1 to 4 further include a joint member having a pipe portion that is disposed to penetrate through an entrance and exit provided in the exterior body, and a mounting portion that is connected to the pipe portion and that is housed inside the exterior body. The heat exchanger according to any one of the above. The heat exchanger according to claim 5, wherein at least a skin portion of the attachment portion of the joint member is made of the same type of heat-sealing resin as the sealant layer of the exterior body.

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