JP2019148373A - Cooling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling device which can be installed in a narrow space and can exhibit excellent heat dissipation performance. SOLUTION: A flat heat pipe having an actuated portion and a non-actuated portion, a cooling member thermally connected to the planar heat pipe, and a thermal connection portion between the flat heat pipe and the cooling member. A cooling device equipped with a provided graphite sheet. [Selection diagram] Fig. 1

Description

  The present invention relates to a cooling device that can be installed in a narrow space and can exhibit excellent heat dissipation performance.

  Electronic parts such as semiconductor elements and batteries mounted on electric / electronic devices have increased in calorific value due to high-density mounting associated with higher functionality, and in recent years, cooling has become more important. As a method for cooling electronic parts and batteries, a cooling device having a planar heat pipe may be used. In recent years, housings for storing electronic components, batteries, and the like have been required to be further reduced in size and weight, and it may be necessary to mount a cooling device in a narrow space.

  In addition, a temperature management system is used for a battery mounted on an electric vehicle or the like for stable operation of the battery. Further, in order to cope with an increase in heat generation accompanying an increase in battery output and to improve battery output and life, in recent years, temperature management systems have been required to further improve heat equalization performance and cooling performance. Further, in order to improve the soaking performance and cooling performance of the cooling device, a graphite sheet having excellent thermal conductivity may be used in combination with the flat heat pipe.

  As a battery system using a flat heat pipe and a graphite sheet in combination, a fuel cell, a heat insulator covering the fuel cell, and a heat transfer member covering the outer surface of the heat insulator, the flat heat pipe as the heat transfer member, It has been proposed to use a graphite sheet together (Patent Document 1).

  However, in the battery system of Patent Document 1, since the five surfaces of the battery are covered with the heat insulator and the heat transfer body, the thickness of the battery system cannot be reduced and cannot be installed in a narrow space. Moreover, in patent document 1, the edge part of the planar heat pipe and graphite sheet which are not thermally connected with a battery functions as a thermal radiation part. Therefore, in Patent Document 1, there is room for improvement in the heat transport characteristics of the flat heat pipe, and hence the heat dissipation characteristics.

JP 2006-202611 A

  In view of the above circumstances, an object of the present invention is to provide a cooling device that can be installed in a narrow space and can exhibit excellent heat dissipation performance.

  Aspects of the present invention include a planar heat pipe having an operating portion and a non-operating portion, a cooling member thermally connected to the planar heat pipe, and a thermal connection between the planar heat pipe and the cooling member. And a graphite sheet provided in the section.

  The working part of the planar heat pipe is a working fluid that exhibits a heat transport function by changing phase in a plan view of the planar heat pipe (when viewed from the vertical direction with respect to the main surface of the planar heat pipe). It means a part corresponding to the enclosed hollow part, and the non-operating part of the planar heat pipe means a part other than the operating part in a plan view of the planar heat pipe.

  An aspect of the present invention is the cooling device in which the cooling member is thermally connected to the operating unit.

  An aspect of the present invention is the cooling device in which the cooling member is thermally connected to the non-operation part.

  An aspect of the present invention is the cooling device in which the cooling member is made of aluminum.

  The aspect of the present invention is the dimension of the graphite sheet on the working part of the planar heat pipe in a direction parallel to the width direction of the working part of the planar heat pipe with respect to the width of the working part of the planar heat pipe. It is a cooling device whose ratio is 0.20 or more and 1.0 or less. In the said aspect, the said dimension ratio is satisfy | filled in at least any one main surface among the both main surfaces of a planar heat pipe.

  An aspect of the present invention is the cooling device in which the graphite sheet extends 20 mm or more from the edge of the operating portion of the planar heat pipe toward the center of the planar heat pipe.

  An aspect of the present invention is the cooling device in which the graphite sheet is provided on the entire main surface of at least one of the main surfaces of the planar heat pipe.

  An aspect of the present invention is a cooling device in which the graphite sheet is provided on the entire main surfaces of the planar heat pipe.

  An aspect of the present invention is the cooling device in which the total thickness of the planar heat pipe, the cooling member, and the graphite sheet is 0.60 mm or less.

  An aspect of the present invention is a cooling device further including a heat conductive plate that extends outward from the planar heat pipe and is thermally connected to the planar heat pipe.

  An aspect of the present invention is a cooling device in which the heat conducting plate is a graphite plate.

  An aspect of the present invention is the cooling device in which the planar heat pipe is provided above the heat conducting plate in the gravity direction.

  An aspect of the present invention is a cooling device in which the planar heat pipe is joined to the cooling member with a heat conductive adhesive.

  An aspect of the present invention is a cooling device installed so that a main surface of the planar heat pipe is disposed at an angle of 0 ° to 45 ° with respect to the direction of gravity.

  An aspect of the present invention is a cooling system in which a heating element is thermally connected to the cooling device and a cooling mechanism is thermally connected to a cooling member to cool the heating element.

  According to the aspect of the cooling device of the present invention, the planar heat pipe is thermally connected to the cooling member, thereby increasing the thickness at the thermal connection portion between the planar heat pipe and the cooling member and the entire cooling device. Since the increase in thickness can be prevented, it can be installed in a narrow space. On the other hand, when the planar heat pipe is thermally connected to the cooling member, a large temperature difference is generated between the heat receiving portion and the heat radiating portion of the planar heat pipe. If a large temperature difference occurs between the heat receiving part and the heat radiating part of the flat heat pipe, the heat transport characteristics of the flat heat pipe may be reduced because the liquid working fluid is easily stored in the heat radiating part. There is sex. However, by providing a graphite sheet at the thermal connection between the planar heat pipe and the cooling member, it is possible to prevent an increase in thickness at the thermal connection, while maintaining the thermal conductivity and thermal diffusion characteristics of the graphite sheet. A temperature difference generated between the heat receiving portion and the heat radiating portion of the planar heat pipe can be reduced. Therefore, according to the aspect of the cooling device of the present invention, excellent heat radiation performance can be exhibited while enabling installation in a narrow space.

  According to the aspect of the present invention, since the cooling member is made of aluminum, it is possible to impart thermal conductivity and rigidity while reducing the weight of the cooling device.

  According to the aspect of the cooling device of the present invention, the ratio of the size of the graphite sheet on the working part in the direction parallel to the width direction of the working part to the width of the working part of the planar heat pipe is 0.20. By being 1.0 or less, the temperature difference generated between the heat receiving portion and the heat radiating portion of the planar heat pipe can be more reliably reduced. Therefore, the cooling device of the present invention can exhibit further excellent heat dissipation performance.

  According to the aspect of the cooling device of the present invention, the graphite sheet extends from the edge of the working portion of the flat heat pipe by 20 mm or more toward the center portion of the flat heat pipe. A temperature difference generated between the heat receiving portion and the heat radiating portion can be further reliably reduced. Therefore, the cooling device of the present invention can exhibit further excellent heat dissipation performance.

  According to the aspect of the cooling device of the present invention, since the graphite sheet is provided on both main surfaces of the flat heat pipe, the heat receiving portion of the flat heat pipe The temperature difference generated between the heat radiating portion and the heat radiating portion can be further reliably reduced. Therefore, the cooling device of the present invention can exhibit further excellent heat dissipation performance even for a cooling target having a high calorific value.

  According to the aspect of the cooling device of the present invention, the main surface of the planar heat pipe is extended from the planar heat pipe in the outward direction by the heat conduction plate thermally connected to the planar heat pipe. Even if the cooling device is installed in a state where the heat sink is erected, the dimension in the height direction of the planar heat pipe can be reduced by the extent that the heat conduction plate extends. Therefore, even if the flat heat pipe is used in a top heat state, dry-out of the flat heat pipe can be prevented. Further, since the graphite plate is extended as the heat conductive plate, the cooling device can be reduced in weight as compared with the case where the graphite plate portion is also a flat heat pipe while having heat conductivity.

It is a top view of the cooling device concerning the example of a 1st embodiment of the present invention. It is explanatory drawing which decomposed | disassembled the cooling device which concerns on the example of 1st Embodiment of this invention. It is side surface sectional drawing of the cooling device which concerns on the example of 1st Embodiment of this invention. It is side surface sectional drawing of the cooling device which concerns on the 2nd Embodiment of this invention. It is side surface sectional drawing of the cooling device which concerns on the example of 3rd Embodiment of this invention. (A) A figure is a top view of the cooling device concerning the example of a 4th embodiment of the present invention, and (b) figure is an AA sectional view of (a) figure. It is a disassembled perspective view before sealing of the flat type heat pipe used with the cooling device concerning the example of an embodiment of the present invention. It is an example of how to use the cooling device according to the first embodiment of the present invention.

  Hereinafter, a cooling device according to a first embodiment of the present invention will be described with reference to the drawings. As shown in FIGS. 1, 2, and 3, the cooling device 1 according to the first embodiment of the present invention includes a planar heat pipe 10 having an operating part 11 and a non-operating part 12, and an operation of the planar heat pipe 10. The cooling member 30 thermally connected to the part 11 and the non-actuating part 12, and the graphite sheet provided in the thermal connecting part 40 between the actuating part 11 and the non-actuating part 12 of the planar heat pipe 10 and the cooling member 30 50.

  The planar heat pipe 10 has a flat plate shape in plan view, and the main surface 13 extends in the heat transport direction of the planar heat pipe 10. A surface connecting both main surfaces 13 of the planar heat pipe 10 is a side surface 14 of the planar heat pipe 10. As shown in FIGS. 1 and 3, the planar heat pipe 10 includes a planar container 20 having a hollow cavity 23 and a working fluid (not shown) sealed in the cavity 23. Yes. A wick structure 25 having a capillary force is accommodated in the cavity 23. The wick structure 25 extends along the cavity 23. The hollow portion 23 in which the working fluid and the wick structure 25 are accommodated is the working portion 11 of the planar heat pipe 10. A heating element to be cooled is thermally connected to the outer surface of the container 20.

  The container 20 having the hollow portion 23 is formed by laminating two opposing plate-like members, that is, one plate-like member 21 and the other plate-like member 22 opposite to the one plate-like member 21. . Therefore, the container 20 has a two-layer structure. One plate-like member 21 and the other plate-like member 22 are laminated at positions where they overlap each other in plan view. One plate-like member 21 is provided with a plastic deformation portion which is a concave portion as viewed from the other plate-like member 22 and which is a convex portion in a side view. By laminating one plate-like member 21 and the other plate-like member 22, the plastic deformation portion forms a cavity portion 23. The cavity 23 extends along the main surface 13 of the planar heat pipe 10.

  Around the hollow portion 23, a closed portion 32 is formed by contacting the peripheral portion of one plate-like member 21 with the peripheral portion of the other plate-like member 22. The blocking part 32 is the non-actuating part 12 of the planar heat pipe 10.

  As shown in FIGS. 1 and 2, the non-actuating part 12 is a peripheral part of the planar heat pipe 10 and is formed on the outer periphery of the actuating part 11. Therefore, as shown in FIG. 3, a step portion 33 corresponding to the amount of deformation of the plastic deformation portion is formed on one plate-like member 21 at the boundary between the non-operation portion 12 and the operation portion 11. The thickness of the non-actuating part 12 is an aspect that is thinner than the thickness of the actuating part 11 by the level difference of the step part 33.

  In the flat heat pipe 10, the outer peripheral portion of the hollow portion 23, that is, the peripheral portion of one plate-like member 21 and the peripheral portion of the other plate-like member 22 are, for example, heat welding means such as laser welding or seam welding. The closed portion 32 is formed by bonding using ultrasonic welding, brazing welding, or the like. By forming the blocking portion 32, the cavity portion 23 is sealed, and airtightness is imparted to the cavity portion 13 that has been subjected to the decompression process. The shape of the cavity 13 in plan view is not particularly limited, and the planar heat pipe 10 has a substantially rectangular shape.

  The material of the container 20 is not particularly limited, and examples thereof include copper, copper alloy, aluminum, aluminum alloy, and stainless steel. The working fluid sealed in the cavity 23 can be appropriately selected according to the compatibility with the material of the container 20, and examples thereof include water, fluorocarbons, cyclopentane, ethylene glycol, and mixtures thereof. it can.

  As shown in FIGS. 1, 2, and 3, the cooling member 30 is thermally connected to the non-operation part 12 of the planar heat pipe 10 and the edge 15 of the operation part 11. In the cooling device 1, the cooling member 30 is provided at a position where the cooling member 30 overlaps the non-operation part 12 of the planar heat pipe 10 and the edge 15 of the operation part 11 in a plan view. The edge part 15 of the part 12 and the action | operation part 11 and the cooling member 30 are thermally connected. In the cooling device 1, a cooling member 30 is attached on the non-operation part 12 and the edge 15 of the operation part 11. A portion where the non-actuating part 12 of the planar heat pipe 10 and the edge 15 of the actuating part 11 overlap with the cooling member 30 in plan view is a thermal connection part 40 of the cooling device 1.

  In the cooling device 1, the cooling member 30 is not provided at a position overlapping with a portion other than the edge portion 15 (that is, the central portion of the operating portion 11) in the operating portion 11 of the planar heat pipe 10 in plan view. Further, in the cooling device 1, the thickness of the cooling member 30 in the non-operating portion 12 is suppressed to be slightly thicker than the step portion of the step portion 33. The main surface 13 and the surface of the cooling member 30 in the operating portion 11 of the planar heat pipe 10 are located in a substantially planar shape. From the above, in the cooling device 1, since it is possible to prevent an increase in the thickness of the thermal connection portion 40 between the planar heat pipe 10 and the cooling member 30, and consequently an increase in the thickness of the entire cooling device 1, the cooling device 1 It can be installed in a small space.

  As shown in FIGS. 1 and 2, in the cooling device 1, cooling members 30 are provided on two of the four sides of the planar heat pipe 10. The cooling members 30 are arranged so as to face each other. Although the shape of the cooling member 30 is not particularly limited, the cooling device 1 is a long flat plate material, and corresponds to the shape of the non-operating portion 12 and the edge portion 15 of the operating portion 11 in plan view. It is a rectangle. The material of the cooling member 30 is not particularly limited as long as it is a material having thermal conductivity, and examples thereof include metals such as aluminum, aluminum alloy, copper, copper alloy, and stainless steel. Aluminum is preferable from the viewpoint of imparting thermal conductivity and rigidity while reducing the weight of 1.

  As a thermal connection means between the planar heat pipe 10 and the cooling member 30, for example, there is a means for bonding the cooling member 30 to the non-operation part 12 and the edge 15 of the operation part 11 using a heat conductive adhesive. Can be mentioned. By joining the planar heat pipe 10 and the cooling member 30 using the thermally conductive adhesive, the heat transfer property between the planar heat pipe 10 and the cooling member 30 is improved. Moreover, the gap formed between the planar heat pipe 10 and the cooling member 30 is bonded by the thermally conductive adhesive by joining the planar heat pipe 10 and the cooling member 30 using the thermally conductive adhesive. Can be filled. Therefore, the heat transfer property between the planar heat pipe 10 and the cooling member 30 is also improved. Examples of the heat conductive adhesive include an epoxy type and an acrylic type.

  In the cooling device 1, the fin portion 31 is provided in the cooling member 30. The fin portion 31 is integrated with the cooling member 30. The fin portion 31 extends from the cooling member 30 in the vertical direction with respect to the main surface 13 of the planar heat pipe 10. The heat transmitted from the planar heat pipe 10 to the cooling member 30 is transmitted from the cooling member 30 to the fin portion 31 and released from the fin portion 31 to the outside.

  In addition, as shown in FIGS. 1, 2, and 3, a graphite sheet 50 is provided at the thermal connection portion 40 between the cooling member 30 and the non-operation portion 12 of the planar heat pipe 10 and the edge portion 15 of the operation portion 11. It has been. The graphite sheet 50 is provided on one plate-like member 21. That is, in the thermal connection part 40, the non-actuating part 12 and the actuating part 11 of the planar heat pipe 10 are arranged in the order of the non-actuating part 12 and actuating part 11 of the planar heat pipe 10, the cooling member 30, and the graphite sheet 50. The cooling member 30 and the graphite sheet 50 are laminated. Therefore, in the thermal connection portion 40, the graphite sheet 50 forms the outermost layer.

  When the planar heat pipe 10 is thermally connected to the cooling member 30, a heat receiving portion (a region thermally connected to a heating element to be cooled) and a heat radiating portion (planar heat pipe) of the planar heat pipe 10. 10, a large temperature difference occurs between the cooling member 30 and the region thermally connected to the cooling member 30. When a large temperature difference occurs between the heat receiving portion and the heat radiating portion of the flat heat pipe 10, it becomes easy to store the liquid-phase working fluid in the heat radiating portion, and the heat transport characteristics and the heat equalization characteristics of the flat heat pipe 10. May be reduced. However, by providing the graphite sheet 50 in the thermal connection portion 40 between the planar heat pipe 10 and the cooling member 30, the thermal conductivity of the graphite sheet 50 can be prevented while preventing an increase in the thickness of the thermal connection portion 40. The temperature difference generated between the heat receiving part and the heat radiating part of the planar heat pipe 10 can be reduced by the heat diffusion characteristics. Therefore, the cooling device 1 can exhibit excellent heat dissipation performance while enabling installation in a narrow space.

  The graphite sheet 50 may be provided on the thermal connection portion 40 between the planar heat pipe 10 and the cooling member 30, but extends further from the thermal connection portion 40 toward the working portion 11 of the planar heat pipe 10. It is preferable. The ratio of the size of the graphite sheet 50 on the working part 11 in the direction parallel to the width direction of the working part 11 with respect to the width of the working part 11 is the temperature generated between the heat receiving part and the heat radiating part of the flat heat pipe 10. From the point that the difference can be more reliably reduced and excellent heat dissipation performance can be exhibited, 0.20 to 1.0 is preferable, 0.40 to 1.0 is more preferable, and 0.60 to 1.0. The following are particularly preferred: In the cooling device 1, the graphite sheet 50 is provided from the thermal connection portion 40 to the entire operation portion 11 of the main surface 13 of the planar heat pipe 10 on one plate-like member 21 side. That is, the entire main surface 13 on the one plate-like member 21 side is covered with the graphite sheet 50. Therefore, in the cooling device 1, the ratio of the above dimensions of the graphite sheet 50 is 1.0. In addition, the ratio of the said dimension of the graphite sheet 50 adds up the said dimension of the divided | segmented graphite sheet 50, when the graphite sheet 50 is divided | segmented and provided in the different position on the action | operation part 11. FIG. This is a calculated value.

  From the above, in the cooling device 1, the graphite sheet 50 forms the outermost layer not only in the thermal joining portion 40 but also in the central portion of the operating portion 11 on the one plate-like member 21 side. Moreover, in the center part of the thermal junction part 40 and the action | operation part 11, the graphite sheet 50 is extended along substantially planar shape. Therefore, in the cooling device 1, the thickness of the part corresponding to the center part of the thermal junction part 40 and the action | operation part 11 is equalized. In the cooling device 1, the graphite sheet 50 extends from the operating portion 11 of the planar heat pipe 10 to the fin portion 31.

  Further, when the graphite sheet 50 extends further from the thermal connection portion 40 toward the operation portion 11 of the planar heat pipe 10, the temperature generated between the heat receiving portion and the heat radiating portion of the planar heat pipe 10. From the point of further reliably reducing the difference, it is preferable that the edge portion 15 of the operating portion 11 of the planar heat pipe 10 extends 20 mm or more toward the central portion of the operating portion 11, and extends 30 mm or more. It is more preferable that, as in the cooling device 1, it is particularly preferable to extend over the entire main surface 13 of the planar heat pipe 10.

  The graphite sheet 50 is either one of the main surfaces 13 of the planar heat pipe 10, that is, the main surface 13 on the one plate member 21 side and the main surface 13 on the other plate member 22 side. 13 may be provided only on both main surfaces 13. As shown in FIG. 3, in the cooling device 1, the graphite sheet 50 is provided not only on the outer surface of one plate-like member 21 but also on the outer surface of the other plate-like member 22. From the above, the graphite sheet 50 extends over both main surfaces 13. Since the graphite sheet 50 is provided on the entire operating portion 11 of both the main surfaces 13, a temperature difference generated between the heat receiving portion and the heat radiating portion of the planar heat pipe 10 even if the heat generation amount to be cooled increases. Can be more reliably reduced. Therefore, the cooling device 1 can exhibit further excellent heat dissipation performance even for a cooling target with a high calorific value.

  The total thickness of the planar heat pipe 10, the cooling member 30, and the graphite sheet 50 is not particularly limited, but is 0.60 mm or less from the viewpoint that the cooling device 1 is securely installed in a narrow space by limiting the thickness. Is preferably 0.50 mm or less. The lower limit of the total thickness of the planar heat pipe 10, the cooling member 30, and the graphite sheet 50 is preferably 0.20 mm from the viewpoint of mechanical strength.

  The means for attaching the graphite sheet 50 to the main surface 13 of the flat heat pipe 10 and the cooling member 30 is not particularly limited. For example, the graphite sheet 50 is heated to a flat heat using a known adhesive such as an acrylic adhesive. The method of adhering to the main surface 13 of the pipe 10 and the cooling member 30 is mentioned.

  Next, a cooling device according to a second embodiment of the present invention will be described with reference to the drawings. In addition, about the same component as the cooling device which concerns on 1st Embodiment, it demonstrates using the same code | symbol.

  In the cooling device according to the first embodiment, the graphite sheet is provided not only on the outer surface of one plate-like member but also on the outer surface of the other plate-like member. As shown in FIG. 4, in the cooling device 2 according to the second embodiment, the graphite sheet 50 is provided on the outer surface of one plate-like member 21, but is not provided on the outer surface of the other plate-like member 22. . From the above, the graphite sheet 50 extends over the entire main surface 13 of one plate-like member 21, but is not provided on the main surface 13 of the other plate-like member 22.

  Even if the graphite sheet 50 is provided only on one of the main surfaces 13, even if the heat generation amount of the cooling target increases, a temperature difference generated between the heat receiving portion and the heat radiating portion of the flat heat pipe 10 is ensured. Can be reduced. Therefore, the cooling device 1 can exhibit excellent heat dissipation performance even for a cooling target with a high calorific value.

  Next, a cooling device according to a third embodiment of the present invention will be described with reference to the drawings. The same components as those of the cooling device according to the first and second embodiments will be described using the same reference numerals.

  In the cooling device according to the first and second embodiments, at least one main surface 13 of the graphite sheet is covered with the graphite sheet 50, and accordingly, in the width direction of the operating portion with respect to the width of the operating portion. On the other hand, the ratio of the size of the graphite sheet on the working part in the parallel direction was 1.0. Instead, as shown in FIG. 5, in the cooling device 3 according to the third embodiment, not the entire main surface 13 of one plate-like member 21 but a part thereof is covered with a graphite sheet 50. In the cooling device 3, the graphite sheet 50 is not provided at the center of the main surface 13 in the direction parallel to the width direction of the operating portion 11. In the cooling device 3, the graphite sheet 50 is provided only on the outer surface of one plate-like member 21, and is not provided on the outer surface of the other plate-like member 22.

  Therefore, in the cooling device 3, the ratio of the said dimension is less than 1.0. Specifically, in the cooling device 3, the ratio of the above dimensions is about 0.60. Even if the graphite sheet 50 is not provided on the entire main surface 13, the temperature difference generated between the heat receiving portion and the heat radiating portion of the planar heat pipe 10 can be reduced by the heat conduction characteristics and heat diffusion characteristics of the graphite sheet 50. Therefore, the cooling device 3 can also exhibit excellent heat dissipation performance.

  Next, a cooling device according to a fourth embodiment of the present invention will be described with reference to the drawings. In addition, about the same component as the cooling device which concerns on the 1st-3rd embodiment, it demonstrates using the same code | symbol.

  As shown in FIGS. 6A and 6B, in the cooling device 4 according to the fourth embodiment, the edge of the planar heat pipe 60 is substantially flush with the main surface 63 of the planar heat pipe 60. Further, from 64, a graphite plate 65 extends. In the cooling device 4, a partial region of the operating portion 11 of the planar heat pipe 10 in the cooling device 1 is replaced with a graphite plate 65. Therefore, in the cooling device 4, the planar heat pipe 60 and the graphite plate 65 have the function of the planar heat pipe 10 in the cooling device 1 described above.

  In the cooling device 4, the cooling member 30 extends from the planar heat pipe 60 to the graphite plate 65. Further, the graphite sheet 50 is provided on both the main surfaces 63 of the flat heat pipe 60 and the entire surface of the graphite plate 65.

  The thermal connection method of the graphite plate 65 and the planar heat pipe 60 is not particularly limited. For example, the non-operation part 62 of the planar heat pipe 60 and the edge 66 of the graphite plate 65 are connected, and the above-mentioned connection part is connected to the above-mentioned connection part. A method of joining the graphite plate 65 and the planar heat pipe 60 by applying a heat conductive adhesive can be mentioned.

  Since graphite is a material having a high thermal conductivity, the planar heat pipe 60 and the graphite plate 65 can be replaced by the graphite plate 65 even if a partial region of the operating portion 11 of the planar heat pipe 10 in the cooling device 1 is replaced with the graphite plate 65. Excellent soaking performance and cooling performance.

  In the cooling device 4, even if the main surface 63 of the flat heat pipe 60 is installed upright, the plane of the graphite plate 65 extends from the edge 64 of the flat heat pipe 60. The dimension in the height direction of the mold heat pipe 60 itself can be reduced. Therefore, even when the planar heat pipe 60 is used in a top heat state, the liquid-phase working fluid (not shown) enclosed in the planar heat pipe 60 is likely to return from the heat radiating section to the heat receiving section. As a result, even if the flat heat pipe 60 is erected and installed, the dry heat pipe 60 can be prevented from being dried out. Further, since the graphite plate 65 is extended, the cooling device 2 can be reduced in weight as compared with the case where the portion of the graphite plate 65 is a planar heat pipe.

  In the cooling device 4, it is preferable that the heating element to be cooled by the cooling device 4 is connected to a portion of the planar heat pipe 60. In the cooling device 4, when the planar heat pipe 60 is installed with the main surface 63 substantially parallel to the gravity direction, the planar heat pipe 60 may be disposed above the graphite plate 65 in the gravity direction. preferable.

  Next, a cooling system using a cooling device according to an embodiment of the present invention will be described with reference to the drawings. Here, using the cooling device 1 according to the first embodiment, the main surface 13 of the planar heat pipe 10 is substantially parallel to the direction of gravity (that is, an angle of about 0 ° to the direction of gravity). The cooling system will be described for the case where the cooling device 1 is installed.

  First, details of the wick structure 25 housed in the cavity 23 of the planar heat pipe 10 will be described with reference to FIG. The wick structure 25 has a substantially rectangular sheet shape corresponding to the shape of the container 20 and the cavity 23 in a plan view being substantially rectangular. The longitudinal direction X of the wick structure 25 corresponds to the longitudinal direction X of the container 20 and the cavity 23, and the transverse direction Y of the wick structure 25 corresponds to the lateral direction Y of the container 20 and the cavity 23.

  A plurality of steam flow paths 26 are formed in the wick structure 25. Further, a portion other than the steam flow path 26 of the wick structure 25 is a wick portion 27 having a capillary force. The steam channel 26 is a hole that penetrates the wick structure 25 in the thickness direction. The steam flow path 26 that is a through hole extends from the central portion in plan view in the longitudinal direction X of the wick structure 25 toward the edge portion in plan view. Therefore, the longitudinal direction of the steam channel 26 corresponds to the longitudinal direction X of the wick structure 25.

  The steam flow path 26 is disposed so as to face each other via a linear imaginary line L that crosses the wick structure 25 at a central portion in plan view in the longitudinal direction X of the wick structure 25. The wick structure 25 is divided by a virtual line L into a first region R1 and a second region R2 having substantially the same shape and area as the first region R1. As shown in FIG. 7, in the first region R1, a plurality of steam channels 26 are arranged in parallel along the virtual line L, and in the second region R2, the other plurality of steam channels 26 are the same. Are arranged in parallel along the virtual line L. Further, in the first region R1 and the second region R2, the respective steam flow paths 26 extend in a direction orthogonal to the virtual line L.

  The steam channel 16 in the first region R1 and the steam channel 16 in the second region R2 are arranged to face each other via an imaginary line L. Correspondingly, the wick portion 27 extends along the imaginary line L. One extended first wick 28 is provided. The first wick 28 is a central portion in plan view in the longitudinal direction X of the wick structure 25, and the other edge that faces the one edge from one edge that forms the longitudinal direction X of the wick structure 25. It extends to. Corresponding to the plurality of steam channels 26 being arranged in parallel along the imaginary line L, the wick portion 27 extends between the steam channels 26 along the longitudinal direction of the steam channel 26. A second wick 29 is provided.

  When the cooling device 1 is installed so that the main surface 13 of the planar heat pipe 10 is substantially parallel to the direction of gravity, the first wick 28 is installed so as to be substantially parallel to the direction of gravity. The working fluid in the liquid phase can flow back from the lower side to the upper side in the direction of gravity along the extending direction of the first wick 28 along the first wick 28 (that is, the central portion in plan view in the longitudinal direction X of the wick structure 25). Further, the vapor channel 26 extends from the central portion in plan view in the longitudinal direction X of the wick structure 25 toward the edge. Therefore, the gas-phase working fluid can flow from the central portion in plan view in the longitudinal direction X of the wick structure 25 toward the edge.

  From the above, in the state where the main surface 13 of the planar heat pipe 10 is installed in the vertical direction, the center of the planar heat pipe 10 is the heat receiving portion and the edge (in FIG. 7, the edge forming the short direction Y). As a heat radiating part, the working fluid whose phase has changed from the liquid phase to the gas phase in the heat receiving part flows in the vapor channel 26 from the central part in plan view in the longitudinal direction X of the wick structure 25 to the edge part. it can. Further, even if the working fluid phase-changed from the gas phase to the liquid phase at the edge of the planar heat pipe 10 flows downward in the gravitational direction due to the action of gravity, the liquid-phase working fluid that flows downward in the gravitational direction is The first wick 28 is refluxed from below to above in the direction of gravity. Also, the liquid-phase working fluid that has not flowed downward in the gravity direction or the liquid-phase working fluid that has not flowed downward in the gravity direction is wicked along the longitudinal direction of the steam flow path 26 by the second wick 29. The structure 25 is refluxed from the edge of the planar portion toward the center. As a result, the liquid-phase working fluid can return from the edge of the wick structure 25 toward the center.

  As shown in FIG. 8, the heating element 100 is thermally connected to the cooling device 1 by thermally connecting the heating element 100 to be cooled to one of the main surfaces 13 of the flat heat pipe 10. . Heating element 100 is mounted on graphite sheet 50 provided on main surface 13. The heating element 100 is installed in a state of being erected in the vertical direction. Correspondingly, the main surface 13 of the planar heat pipe 10 is installed substantially parallel to the direction of gravity (that is, an angle of about 0 ° with respect to the direction of gravity), and corresponds to the center of the main surface 13 and its vicinity. The heating element 100 is thermally connected to the portion to form a heat receiving portion of the flat heat pipe 10. In the cooling device 1, both edge portions of the operating portion 11 and both edge portions of the operating portion 11 (in FIG. 8, both edge portions forming the short direction Y of the planar heat pipe 10 and the short direction Y of the wick structure). The cooling member 30 is attached to the non-actuating part 12 extending from (). Further, if necessary, a cooling mechanism (not shown) such as a water cooling jacket may be thermally connected to the cooling member 30 to further improve the cooling effect on the heating element 100.

  As described above, even when the cooling device 1 is installed in a state where the flat heat pipe 10 is erected, the working fluid in the gas phase smoothly flows through the center of the flat heat pipe 10 by the action of the wick structure 25. The working fluid in the liquid phase can smoothly flow from both edges of the working part of the planar heat pipe 10 to the central direction. Therefore, the cooling device 1 can exhibit excellent soaking and cooling performance with respect to the heating element 100.

  Next, another embodiment of the cooling device of the present invention will be described. In the cooling device according to each of the above-described embodiments, the cooling member that is a long flat plate material is provided on two of the four sides of the planar heat pipe. The frame cooling member may be attached to the non-operating portion of the planar heat pipe. In this case, a cooling member is provided on the four sides of the planar heat pipe. In the cooling device according to each embodiment described above, the cooling member, which is a long flat plate material, is mounted on the non-operating part. Instead, the block-shaped cooling member is provided on the non-operating part. It may be attached to. Moreover, a block-shaped cooling member may be joined to a non-operation part by providing a groove part in a block-shaped cooling member, inserting a non-operation part in this groove part, and crimping a cooling member.

  Moreover, in each said embodiment, the cooling member was thermally connected from the non-operation part of the planar heat pipe to the edge part of the operation part, and the thermal connection part was formed. That is, the non-actuating part of the planar heat pipe, the edge of the actuating part, and the cooling member overlap each other in plan view, so that the thermal connection part is formed. Alternatively, only the non-operating part of the planar heat pipe may be thermally connected to the cooling member, or only the operating part of the planar heat pipe may be thermally connected to the cooling member. That is, only the non-operating part of the planar heat pipe and the cooling member may overlap in a plan view so that a thermal connection part may be formed, and only the operating part of the planar heat pipe and the cooling member overlap in a plan view. A thermal connection may be formed.

  Moreover, in each said embodiment, although the fin part was provided in the cooling member which is a long flat plate material, it replaces with this and it is good also as a cooling member by extending further a non-operation part outside. Furthermore, it is good also as an aspect by which the site | part which extended the non-operation part further outside was bent in the perpendicular direction, and the fin part was provided in the cooling member.

  In the above usage example, the main surface of the planar heat pipe is installed at an angle of approximately 0 ° with respect to the direction of gravity. Instead, it is installed at an angle of greater than 0 ° and less than 45 ° with respect to the direction of gravity. Alternatively, it may be installed at more than 45 ° and less than 90 ° with respect to the gravitational direction, and may be installed at 90 ° with respect to the gravitational direction (that is, the main surface of the planar heat pipe is in the horizontal direction).

  Further, in the cooling device according to the fourth embodiment, the graphite plate further extends from the edge of the flat heat pipe. However, the plate is not limited to the graphite plate as long as it is a plate material having thermal conductivity. For example, a metal plate such as copper or aluminum may be used.

  Since the cooling device of the present invention can be installed even in a narrow space and can exhibit excellent cooling performance, it can be used, for example, in the field of cooling battery cells.

DESCRIPTION OF SYMBOLS 10, 60 Planar type heat pipe 11, 61 Operation part 12, 62 Non-operation part 13 Main surface 30 Cooling member 40 Thermal connection part 50 Graphite sheet 65 Graphite plate

Claims (15)

  A planar heat pipe having an operating part and a non-operating part, a cooling member thermally connected to the planar heat pipe, and graphite provided at a thermal connection part between the planar heat pipe and the cooling member And a cooling device.   The cooling device according to claim 1, wherein the cooling member is thermally connected to the operating portion.   The cooling device according to claim 1, wherein the cooling member is thermally connected to the non-operation part.   The cooling device according to any one of claims 1 to 3, wherein the cooling member is made of aluminum.   The dimensional ratio of the graphite sheet on the working part of the planar heat pipe in the direction parallel to the width direction of the working part of the planar heat pipe to the width of the working part of the planar heat pipe is 0.20. The cooling device according to any one of claims 1 to 4, wherein the cooling device is 1.0 or more and 1.0 or less.   The cooling device according to any one of claims 1 to 5, wherein the graphite sheet extends from an edge of an operating portion of the planar heat pipe by 20 mm or more toward a central portion of the planar heat pipe.   The cooling device according to any one of claims 1 to 6, wherein the graphite sheet is provided on at least one main surface of both main surfaces of the planar heat pipe.   The cooling device according to any one of claims 1 to 7, wherein the graphite sheet is provided on both main surfaces of the planar heat pipe.   The cooling device according to any one of claims 1 to 8, wherein a total thickness of the planar heat pipe, the cooling member, and the graphite sheet is 0.60 mm or less.   The cooling device according to any one of claims 1 to 9, further comprising a heat conduction plate that extends outward from the planar heat pipe and is thermally connected to the planar heat pipe.   The cooling device according to claim 10, wherein the heat conductive plate is a graphite plate.   The cooling device according to claim 10 or 11, wherein the planar heat pipe is provided above the heat conducting plate in the gravity direction.   The cooling device according to any one of claims 1 to 12, wherein the planar heat pipe is joined to the cooling member by a thermally conductive adhesive.   The cooling device according to any one of claims 1 to 13, wherein the main surface of the planar heat pipe is installed so as to be disposed at an angle of 0 ° to 45 ° with respect to the direction of gravity.   A cooling system that cools the heating element by thermally connecting the heating element to the cooling device according to claim 1 and thermally connecting a cooling mechanism to the cooling member.

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