JP2018078224A - Heat conduction device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat conduction device which can achieve a reduction in weight of a graphene sheet without impairing heat conductivity in an in-plane direction.SOLUTION: A heat conduction device 1 comprises: a heating member 2 which generates heat by energy supplied thereto; a heat dissipation member 3 which dissipates the heat of the heating member 2 to the outside; and a graphene sheet 10 which is a heat-conducting member connecting between the heating member 2 and the heat dissipation member 3 so as to enable heat-conduction therebetween. The graphene sheet 10 comprises: a heat-absorbing part 13 directly or indirectly brought into contact with the heating member 2 in a thickness direction of the graphene sheet 10; and a heat-conducting part 14 extending from the heat-absorbing part 13, and having a leading end directly or indirectly brought into contact with the heat dissipation member 3. The heat-conducting part 14 is formed in a substantially sheet-like shape having a predetermined thickness. The heat-absorbing part 13 has a plurality of faces substantially opposed to the heating member 2 in the thickness direction. The heat-absorbing part is folded in a three-dimensional shape having a length equal to or larger than a thickness of the heat-conducting part 14 in the thickness direction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a heat conduction device including a graphite sheet which is a heat conduction member that connects, for example, a heat generation member that generates heat by supplied energy and a heat dissipation member that radiates heat from the heat generation member.

  In recent years, a graphite sheet (also referred to as graphene sheet) is known as a heat conductive member having excellent heat conductivity. This graphite sheet is a hexagonal lattice structure in which a combination of carbon atoms bonded in a substantially hexagonal shape is connected along a two-dimensional plane, and is directed in an in-plane direction (also referred to as a plane direction or a plane direction). It has a feature of high thermal conductivity.

  As a heat conduction device using such a graphite sheet, Patent Document 1 discloses a heat conduction device using a heat conduction member formed by laminating a plurality of strips of graphite sheets coated with a film. Yes.

By the way, when the heat generating member and the graphite sheet are brought into contact with each other in the thickness direction of the graphite sheet so as to be able to conduct heat, most of the heat transferred from the heat generating member to the graphite sheet is not converted into heat transfer in the in-plane direction. It has been confirmed by the applicant that heat is released from the graphite sheet into the atmosphere along the thickness direction.
That is, the graphite sheet tends to have a lower thermal conductivity in the thickness direction or a lower thermal conductivity from the thickness direction to the in-plane direction than the thermal conductivity in the in-plane direction.

For this reason, for example, when a plurality of graphite sheets are laminated in the thickness direction in order to secure a desired amount of heat transfer in the in-plane direction, not only a large amount of graphite sheets are required, but also a factor of weight increase There was a problem of becoming.
Furthermore, since the graphite sheet is not an inexpensive heat conducting member, there has been a need to reduce the amount of graphite sheet used without impairing the amount of heat transfer in the in-plane direction.

Japanese Patent Laid-Open No. 2006-92357

  In view of the above problems, an object of the present invention is to provide a heat conduction device that can reduce the weight of a graphite sheet without impairing the thermal conductivity in the in-plane direction.

  The present invention provides a heat generating member that generates heat by supplied energy, a heat dissipating member that dissipates heat of the heat generating member to the outside, a heat conductive member that connects the heat generating member and the heat dissipating member so as to allow heat conduction. A heat conduction device provided with a graphite sheet, wherein the graphite sheet extends directly from the heat absorbing portion, directly or indirectly in contact with the heat generating member in the thickness direction of the graphite sheet. A heat conduction part that directly or indirectly contacts the heat radiating member, the heat conduction part is formed in a substantially sheet shape having a predetermined thickness, and the heat absorption part generates the heat in the thickness direction. It has a plurality of surfaces substantially opposite to the member and is folded into a three-dimensional shape having a length in the thickness direction that is equal to or greater than the thickness of the heat conducting portion.

The heat generating member can be, for example, a coil that generates a magnetic field when power is supplied, or an electrical component that operates when power is supplied.
The heat radiating member can be, for example, a housing case that houses and holds the heat generating member, or a heat radiating plate having thermal conductivity.
The indirect contact means that the graphite sheet is in contact with the heat generating member and the heat radiating member through, for example, a paste having insulating properties and thermal conductivity.

The graphite sheet may be a graphite sheet alone or a graphite sheet coated with a heat conductive film.
The three-dimensional shape is, for example, a substantially corrugated shape in which a substantially mountain shape projecting in the thickness direction continues along the in-plane direction in the heat conducting portion, or a substantially sheet-like developed shape is folded back so as to overlap in the thickness direction. It refers to the formed shape.

According to the present invention, the weight of the graphite sheet can be reduced without impairing the thermal conductivity in the in-plane direction.
Specifically, since the heat conduction part of the graphite sheet is formed in a substantially sheet shape, the heat conduction device is configured by integrally folding the heat absorption part and the heat conduction part by folding one graphite sheet. As compared with the above, the amount of graphite sheet used in the heat conducting part can be suppressed. For this reason, the heat conduction device can reduce the weight of the graphite sheet and can reduce the cost.

  On the other hand, for example, when the heat absorption part is formed in a substantially wave shape continuous in the in-plane direction of the heat conduction part, or in a shape overlapping in the thickness direction, the heat absorption part of the graphite sheet is a plurality of substantially opposite to the heat generating member in the thickness direction. The area of the surface can be ensured wider than that of the substantially sheet-like heat absorbing portion. For this reason, the heat conducting device can efficiently absorb the heat of the heat generating member as compared with the substantially sheet-like heat absorbing portion.

Furthermore, since the thermal conductivity in the thickness direction of the heat absorption part of the graphite sheet is low, the total amount of heat absorbed by the heat absorption part is unlikely to exceed the limit value of the amount of heat transfer in the in-plane direction of the heat conduction part.
Thereby, even if it suppresses the usage-amount of the graphite sheet in a heat conductive part, the heat conductive apparatus can carry out heat conduction stably to the heat radiating member to the heat radiating member.
Therefore, the heat conducting device can reduce the weight of the graphite sheet without impairing the heat conductivity in the in-plane direction.

As an aspect of the present invention, the endothermic portion of the graphite sheet is formed to be bent into a substantially corrugated shape or a substantially bellows shape continuous in the in-plane direction of the heat conducting portion.
According to the present invention, the heat conduction device can suppress the amount of graphite sheet used in the heat conduction part, while ensuring a larger area of the surface of the heat absorption part facing the heat generating member than the substantially sheet-like heat absorption part. can do.

  Further, for example, when the heat absorption part is formed in a substantially waveform shape, an inclined part inclined with respect to the thickness direction in the unfolded state is formed in the heat absorption part, so the heat absorption part of the graphite sheet is a part of the heat in the heat generating member. Can be absorbed along the in-plane direction of the inclined portion. For this reason, the heat conduction device can increase the amount of heat transfer in the in-plane direction.

  In addition, since the endothermic part can be easily configured by bending one end side of the substantially band-shaped developed shape, the heat conduction device uses a graphite sheet molded from a sheet-like material with a high yield as the heat conduction member. be able to. Thereby, the heat conduction apparatus can efficiently use an inexpensive graphite sheet.

  Therefore, the heat conduction device reduces the weight of the graphite sheet and efficiently uses the graphite sheet without impairing the thermal conductivity in the in-plane direction by the heat absorption part bent into a substantially corrugated shape or a substantially bellows shape. Can be compatible.

  Further, as an aspect of the present invention, the heat absorbing portion of the graphite sheet extends from the contact portion in the in-plane direction of the contact portion, and a contact portion that directly or indirectly contacts the heat generating member. A first extended portion folded back to overlap with the contact portion, and extended from the first extended portion in an in-plane direction of the first extended portion and folded back toward the contact portion. And the second extended portion.

  According to the present invention, the heat conduction device can suppress the amount of graphite sheet used in the heat conduction part, while ensuring a larger area of the surface of the heat absorption part facing the heat generating member than the substantially sheet-like heat absorption part. can do.

  Further, the graphite sheet absorbs heat radiated in the thickness direction from the contact portion of the heat absorbing portion at the second extending portion, and absorbs heat radiated from the second extending portion in the thickness direction at the first extending portion. can do. For this reason, the heat conduction device can increase the total amount of heat absorbed by the endothermic portion of the graphite sheet as compared to the case where the endothermic portion of the graphite sheet is configured only by the contact portion.

  In addition, since the endothermic part can be easily configured by bending one end side of the substantially band-shaped developed shape, the heat conduction device uses a graphite sheet molded from a sheet-like material with a high yield as the heat conduction member. be able to. Thereby, the heat conduction apparatus can efficiently use an inexpensive graphite sheet.

  Therefore, the heat conduction device achieves both weight reduction of the graphite sheet and efficient use of the graphite sheet without impairing the thermal conductivity in the in-plane direction by the heat absorption part folded in the thickness direction. Can do.

  As an aspect of the present invention, the endothermic portion of the graphite sheet extends from the contact portion in at least two directions in the in-plane direction of the contact portion, and a contact portion that directly or indirectly contacts the heat generating member. And a plurality of extended portions each folded so as to overlap with the contact portion.

  According to the present invention, the heat conduction device can suppress the amount of graphite sheet used in the heat conduction part, while ensuring a larger area of the surface of the heat absorption part facing the heat generating member than the substantially sheet-like heat absorption part. can do.

Furthermore, since the extending portion is formed in at least two directions in the in-plane direction at the contact portion, the path from the extending portion to the heat conducting portion via the contact portion is substantially omitted from any extending portion. Same distance.
In addition, the graphite sheet can absorb the heat radiated from the contact portion of the heat absorbing portion in the thickness direction at the plurality of extending portions.

  For this reason, the heat conduction device can not only increase the total amount of heat absorbed by the endothermic portion of the graphite sheet, but also each extending portion can be compared with the case where the endothermic portion of the graphite sheet is configured only by the contact portion. The absorbed heat can be efficiently conducted to the heat conducting portion.

Furthermore, for example, when one extended portion is folded back multiple times and folded into a contact portion, there is a possibility that lattice defects may occur in the hexagonal lattice structure in the heat absorbing portion due to multiple folding.
On the other hand, since the extension part can be folded into the contact part by one folding per one extension part, the heat conduction device has a lattice defect in the hexagonal lattice structure in the heat absorption part. Can be prevented.

  Therefore, the heat conduction device is intended to reduce the weight of the graphite sheet without impairing the thermal conductivity in the in-plane direction by the heat absorption part configured by folding a plurality of extending portions extending in the in-plane direction. Can do.

  According to the present invention, it is possible to provide a heat conduction device capable of reducing the weight of the graphite sheet without impairing the thermal conductivity in the in-plane direction.

FIG. 3 is an external perspective view illustrating an external appearance of a heat conduction device according to the first embodiment. The side view which shows the side view of a heat conductive apparatus. Explanatory drawing explaining the formation process of a heat absorption part. The side view which shows the side view of another graphene sheet. FIG. 6 is an external perspective view showing an external appearance of a heat conduction device in Example 2. Explanatory drawing explaining the heat absorption part in Example 2. FIG. FIG. 6 is an external perspective view showing an external appearance of a heat conduction device in Example 3. Explanatory drawing explaining the heat absorption part in Example 3

  An embodiment of the present invention will be described below with reference to the drawings.

The heat conduction device 1 according to the first embodiment will be described in detail with reference to FIGS. 1 to 3.
1 is an external perspective view of the heat conduction device 1 in the first embodiment, FIG. 2 is a side view of the heat conduction device 1, and FIG. 3 is an explanatory view for explaining a molding process of the heat absorbing portion 13. Yes.

In addition, in order to clarify illustration in FIG. 1, illustration of the heat absorption side pressing member 4 and the heat radiation side pressing member 5 is abbreviate | omitted.
Further, in FIG. 1, an arrow X indicates the front-rear direction (hereinafter referred to as “front-rear direction X”), and an arrow Y indicates the width direction (hereinafter referred to as “width direction Y”). Further, the upper side in FIG. 1 is the upper side, and the lower side in FIG. 1 is the lower side.

  As shown in FIGS. 1 and 2, the heat conduction device 1 is disposed at a position spaced apart from the heat generating member 2 that generates heat by supplying predetermined energy, and a predetermined distance rearward from the heat generating member 2, and the heat generating member 2. A heat radiating member 3 that radiates the heat of the outside, a graphene sheet 10 that is a heat conductive member having a front end placed on the heat generating member 2 and a rear end placed on the heat radiating member 3, and a front portion of the graphene sheet 10 The heat absorption side pressing member 4 to be pressed and the heat radiation side pressing member 5 to press the rear part of the graphene sheet 10 are configured.

The heat generating member 2 is a member in which a part of predetermined energy supplied from the outside is converted into heat energy, and is, for example, a coil wound around a stator of an electric motor.
In addition, as shown in FIG. 2, the heat conductive paste 6 which fills the clearance gap with the graphene sheet 10 is apply | coated to the upper surface of the heat generating member 2. As shown in FIG. This heat conductive paste 6 is a paste material having insulating properties and heat conductivity, and is produced by, for example, a hydrolysis reaction of an alkoxide compound and a silanol dehydration condensation reaction.

The heat radiating member 3 is a metal member having good thermal conductivity and heat radiating properties, and is, for example, a housing case that houses and holds a rotor and a stator in an electric motor. As shown in FIG. 1, the heat radiating member 3 is integrally formed with a placement portion 3 a on which the rear end of the graphene sheet 10 is placed and a side wall portion 3 b erected upward from the placement portion 3 a. .
Further, as shown in FIG. 2, a heat conductive paste 6 that fills a gap with the graphene sheet 10 is applied to the upper surface of the mounting portion 3 a and the front surface of the side wall portion 3 b in the heat radiating member 3.

  In addition, the graphene sheet 10 is a hexagonal lattice structure in which a combination of carbon atoms bonded in a substantially hexagonal shape is connected along a two-dimensional plane, and is formed in a thin film sheet shape with a thickness of 10 μm to 100 μm. ing. This graphene sheet 10 has good thermal conductivity in the in-plane direction (the front-rear direction X and the width direction Y in the figure) in a state of being developed in a substantially sheet shape, for example, when the thickness is 50 μm It has a thermal conductivity in the in-plane direction of about 1300 W / m · k.

  And the graphene sheet 10 in a present Example is cut out and formed in the strip | belt-shaped body long in the front-back direction X from the substantially sheet-like raw material, as shown in FIG. Further, the graphene sheet 10 is formed such that the front part of the cut strip is bent into a three-dimensional shape having a height equal to or greater than the thickness of the graphene sheet 10 in the vertical direction.

  Specifically, as shown in FIG. 1, the graphene sheet 10 includes a heat dissipating part 11 placed on the heat dissipating member 3, a heat transfer part 12 extending forward from the heat dissipating part 11, and the heat generating member 2. It is mounted and integrally formed with the heat absorbing portion 13 that absorbs the heat of the heat generating member 2.

  As shown in FIGS. 1 and 2, the heat radiating portion 11 is formed in a substantially rectangular shape in plan view that is long in the front-rear direction X. As shown in FIG. 2, the heat dissipating part 11 has a heat conductive paste on the upper surface of the mounting part 3a of the heat dissipating member 3 with its rear end in contact with the side wall part 3b of the heat dissipating member 3 in the front-rear direction X. 6 is placed.

As shown in FIGS. 1 and 2, the heat transfer unit 12 is formed in a substantially rectangular shape in plan view that extends forward from the front end of the heat dissipation unit 11.
That is, the graphene sheet 10 is a substantially band-shaped part formed by the heat dissipation part 11 and the heat transfer part 12 described above, and constitutes a heat conduction part 14 that conducts heat absorbed by the heat absorption part 13 to the heat dissipation member 3. ing.

As shown in FIG. 1 and FIG. 2, the endothermic part 13 folds the portions extending forward from the front end of the heat transfer part 12 alternately at a plurality of positions at a predetermined interval in the front-rear direction X. It is formed into a three-dimensional shape folded in the valley.
In addition, the heat absorption part 13 is mounted through the heat conductive paste 6 on the upper surface of the heat generating member 2, as shown in FIG.

  More specifically, as shown in FIG. 2, the heat absorbing portion 13 is bent substantially upward, and a substantially chevron shape in which a front portion is further bent downward is repeated from the rear toward the front. It is formed in a corrugated shape.

  Furthermore, as shown in FIG. 2, the top 13a and the valley 13b of the heat absorbing part 13 are each bent and formed in a substantially arc shape having a predetermined radius in order to prevent the occurrence of lattice defects in the hexagonal lattice structure. .

  As shown in FIG. 2, the endothermic portion 13 formed in such a substantially wave shape has a lower surface of the inclined portion 13 c inclined in the vertical direction in the state of being placed on the heat generating member 2 in the front-rear direction. While facing substantially each other, facing the upper surface of the heat generating member 2 in the direction along the thickness of the inclined portion 13c, the top surface 13a of the heat absorbing portion 13 and the lower surface of the valley portion 13b face the upper surface of the heat generating member 2 in the vertical direction. doing.

  As shown in FIG. 3, the endothermic portion 13 guides a substantially round bar-shaped bending jig 15 that is long in the width direction Y when the three-dimensional endothermic portion 13 is formed from the developed shape developed in a substantially band shape. Thus, the substantially strip-shaped apex portion 13a and trough portion 13b are formed by bending the unfolded belt-like body.

  Further, as shown in FIG. 2, the heat absorption side pressing member 4 is a flat plate having a predetermined thickness in the vertical direction, and the top portion of the heat absorption portion 13 of the graphene sheet 10 in a state where the heat conductive paste 6 is applied. 13a. The heat absorption side pressing member 4 is fixed so as to press the heat absorption part 13 with a pressing load that does not crush the heat absorption part 13 formed in a three-dimensional shape.

  Further, as shown in FIG. 2, the heat radiation side pressing member 5 is a flat plate having a predetermined thickness in the vertical direction, and a heat radiation portion 11 of the graphene sheet 10 is applied in a state where a heat radiation paste (not shown) is applied. Is placed. The heat radiation side pressing member 5 is fixed so as to press the heat radiation part 11 with a pressing load that does not crush the heat radiation part 11.

The heat conduction device 1 that realizes the above configuration can reduce the weight of the graphene sheet 10 without impairing the thermal conductivity in the in-plane direction.
Specifically, since the heat conducting portion 14 of the graphene sheet 10 is formed in a substantially sheet shape, the heat conducting device 1 folds one graphene sheet so that the heat absorbing portion and the heat conducting portion are integrated. Compared with the case where it comprises, the usage-amount of the graphene sheet 10 in the heat conductive part 14 can be suppressed. For this reason, the heat conduction apparatus 1 can reduce the weight of the graphene sheet 10 and can reduce the cost.

  On the other hand, by forming the heat absorbing portion 13 in a substantially waveform shape that is continuous in the in-plane direction of the heat conducting portion 14, the heat absorbing portion 13 of the graphene sheet 10 has an area of the lower surface that substantially faces the heating member 2 in the vertical direction. Compared with the substantially sheet-like heat absorption part 13, it can ensure widely. For this reason, the heat conduction device 1 can absorb the heat of the heat generating member 2 more efficiently than the substantially sheet-like heat absorption part 13.

  Furthermore, since the heat conductivity in the thickness direction of the heat absorbing portion 13 of the graphene sheet 10 is low, the total heat absorbed by the heat absorbing portion 13 exceeds the limit value of the amount of heat transfer in the in-plane direction of the heat conducting portion 14. Hateful.

Thereby, even if the heat conductive apparatus 1 suppresses the usage-amount of the graphene sheet 10 in the heat conductive part 14, it can carry out the heat conduction to the heat radiating member 3 stably to the heat radiating member 3 even if it absorbs heat.
Therefore, the heat conducting device 1 can reduce the weight of the graphene sheet 10 without impairing the heat conductivity in the in-plane direction.

  Moreover, the heat-absorbing part 13 of the graphene sheet 10 is formed in a substantially waveform shape that is continuous in the in-plane direction, so that the heat conduction device 1 can suppress the amount of the graphene sheet 10 used in the heat conduction part 14. On the other hand, the area of the lower surface of the heat absorbing portion 13 facing the heat generating member 2 can be secured larger than that of the substantially sheet-like heat absorbing portion.

  Furthermore, since the inclined part 13c inclined with respect to the up-down direction is formed in the heat absorbing part 13, the heat absorbing part 13 of the graphene sheet 10 passes a part of the heat in the heating member 2 along the in-plane direction in the inclined part 13c. Can absorb heat. For this reason, the heat conducting apparatus 1 can increase the amount of heat transfer in the in-plane direction.

  In addition, since the endothermic portion 13 can be easily configured by bending one end side of the substantially band-shaped developed shape, the heat conduction device 1 can conduct heat conduction to the graphene sheet 10 formed from a sheet-like material with high yield. It can be used as a member. Thereby, the heat conductive apparatus 1 can utilize the graphene sheet 10 which is not cheap efficiently.

  Therefore, the heat conducting device 1 is configured to reduce the weight of the graphene sheet 10 and to efficiently use the graphene sheet 10 without impairing the thermal conductivity in the in-plane direction by the heat absorbing portion 13 bent into a substantially waveform shape. Can be compatible.

  Further, the heat conduction device 1 conducts heat from the heat transfer part 12 of the graphene sheet 10 to the heat dissipation part 11 by bringing the rear end of the heat dissipation part 11 in the graphene sheet 10 into contact with the side wall part 3 b of the heat dissipation member 3. The generated heat can be directly transferred to the side wall 3b of the heat radiating member 3. Thereby, the heat conducting apparatus 1 can efficiently conduct heat of the heat generating member 2 to the heat radiating member 3 through the graphene sheet 10.

  In addition, in Example 1 mentioned above, although the heat absorption part 13 of the graphene sheet 10 was formed in the solid shape bent in the substantially waveform shape continuous in the front-back direction X, it is not limited to this, For example, another graphene sheet 10 As shown in FIG. 4 showing a side view of the heat transfer portion 12, a heat absorbing portion 16 having a substantially bellows shape that continues from the front end toward the front may be used.

  More specifically, as shown in FIG. 4, in the heat absorbing portion 16, only the bottom surfaces of the top portion 16 a and the valley portion 16 b are opposed to the top surface of the heat generating member 2 in the vertical direction, and the other portions are spaced in the front-rear direction X by a predetermined interval. Are formed in a substantially bellows shape facing each other.

  Thereby, the graphene sheet 10 can directly transmit the heat of the heat generating member 2 to the in-plane directions of the portions facing each other in the front-rear direction X via the valley portions 16 b of the heat absorbing portion 16. For this reason, since the heat absorption part 16 of the graphene sheet 10 can eliminate the conversion of the heat transfer direction from the thickness direction to the in-plane direction, it can efficiently absorb the heat of the heat generating member 2.

Moreover, although the heat absorption part 13 of the graphene sheet 10 was formed in the three-dimensional shape bent in the substantially waveform shape which continues in the front-back direction X, it does not limit to this, It forms in the substantially rectangular wave shape continuous in the front-back direction X. Also good.
Further, the upper surface of the heat generating member 2 may be formed in an uneven shape corresponding to the unevenness in the heat absorbing portion 13 of the graphene sheet 10.

Next, a heat conduction device 7 having a graphene sheet shape different from that of the heat conduction device 1 according to the first embodiment will be described with reference to FIGS. 5 and 6.
The same configurations as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  5 shows an external perspective view of the heat conducting device 7 in the second embodiment, FIG. 6 shows an explanatory view for explaining the heat absorbing portion 23 in the second embodiment, and FIG. 6A shows the heat absorbing portion 23 in the unfolded state. 6 (b) shows an external perspective view of the heat absorbing part 23 in the first molding process, and FIG. 6 (c) shows an external perspective view of the heat absorbing part 23 in the second molding process. .

  Moreover, in order to clarify illustration in FIG. 5, illustration of the heat absorption part pressing member and the heat radiating part pressing member is abbreviate | omitted. Further, in FIG. 6A, the boundary between the heat transfer part 22 and the contact part 23a of the heat absorption part 23 is indicated by a two-dot chain line L1, and the boundary between the contact part 23a and the first extension part 23b is indicated by two points. It is illustrated by a chain line L2, and a boundary between the first extending part 23b and the second extending part 23c is illustrated by a two-dot chain line L3.

  As shown in FIGS. 5 and 6A, the graphene sheet 20 of the heat conduction device 7 in Example 2 is formed by cutting a substantially sheet-like material into a strip-like body that is long in the front-rear direction X. Further, the graphene sheet 20 is formed such that the front portion in the developed shape is bent into a three-dimensional shape having a height equal to or greater than the thickness of the graphene sheet 20 in the vertical direction.

  Specifically, as illustrated in FIG. 5, the graphene sheet 20 includes a heat dissipating part 21 placed on the heat dissipating member 3, a heat transfer part 22 extending forward from the heat dissipating part 21, and the heat generating member 2. The heat-absorbing part 23 is integrally formed with the heat-absorbing part 23 that absorbs the heat of the heat-generating member 2.

  In addition, the heat conduction part 24 comprised by the thermal radiation part 21 and the heat transfer part 22 of the graphene sheet 20 in Example 2 is comprised by the thermal radiation part 11 and the heat transfer part 12 of the graphene sheet 10 in Example 1 mentioned above. Since the configuration is the same as that of the heat conduction unit 14, detailed description thereof is omitted.

  As shown in FIG. 6A, the heat absorbing portion 23 of the graphene sheet 20 has a substantially rectangular shape in plan view, a contact portion 23a continuous from the front end of the heat transfer portion 22, and a front end of the contact portion 23a. The first extending portion 23b extends and the second extending portion 23c extends from the front end of the first extending portion 23b.

Then, as shown in FIG. 5, the heat absorbing portion 23 is folded back so that the contact portion 23a, the second extending portion 23c, and the first extending portion 23b are folded in this order from below, and has a height in the vertical direction. It is formed in a three-dimensional shape having
In addition, between the contact part 23a and the 1st extension part 23b, the thermal radiation paste which abbreviate | omitted illustration shall be filled.

  More specifically, as shown in FIGS. 5 and 6A, the contact portion 23 a of the heat absorbing portion 23 is formed in a substantially rectangular shape in plan view having a size corresponding to the upper surface of the heat generating member 2. The lower surface of the contact portion 23a is indirectly in contact with the upper surface of the heat generating member 2 through a heat radiation paste (not shown).

  As shown in FIG. 5, the first extending portion 23b of the heat absorbing portion 23 extends in a substantially rectangular shape in plan view having a size substantially equal to that of the contact portion 23a. The first extended portion 23b is located at a predetermined distance above the contact portion 23a, and the upper surface in the unfolded state is the upper surface of the heat generating member 2 with the contact portion 23a and the second extended portion 23c interposed therebetween. It is folded so as to face.

  As shown in FIG. 5, the second extending portion 23c of the heat absorbing portion 23 is extended in a substantially rectangular shape in plan view in which the length in the front-rear direction X is slightly shorter than the contact portion 23a. The second extending portion 23c is located between the contact portion 23a and the first extending portion 23b, and is folded back so that the lower surface in the unfolded state faces the upper surface of the heat generating member 2 with the contact portion 23a interposed therebetween. ing.

Subsequently, in the graphene sheet 20 described above, a process of forming the heat absorbing portion 23 having a height in the vertical direction by folding the first extending portion 23b and the second extending portion 23c in the unfolded state will be described.
In addition, the 1st extension part 23b and the 2nd extension part 23c shall each be return | folded using the bending jig which abbreviate | omitted illustration similarly to Example 1 mentioned above.

  First, as shown in FIGS. 6 (a) and 6 (b), the second extending portion 23c of the heat absorbing portion 23 in the graphene sheet 20 cut out in a substantially rectangular strip in plan view is shown in FIG. 6 (a). It is folded back upward and rearward at the position of the middle two-dot chain line L3 and is folded on the upper surface of the first extending portion 23b.

Thereafter, as shown in FIGS. 6B and 6C, the first extending portion 23b is folded at the position of the two-dot chain line L2 in FIG. It is folded and folded on the upper surface of the contact portion 23a.
Thus, the heat absorption part 23 is a three-dimensional object having a height equal to or greater than the thickness of the graphene sheet 20 in the vertical direction by folding the first extension part 23b and the second extension part 23c with respect to the contact part 23a. It is formed into a shape.

  Since the heat conduction device 7 having the above-described configuration can suppress the amount of the graphene sheet 20 used in the heat conduction part 24 as in the first embodiment, the heat conductivity in the in-plane direction is impaired. In addition, the weight of the graphene sheet 20 can be reduced.

  In addition, the heat absorption part 23 of the graphene sheet 20 is in contact with the heat generating member 2 indirectly, a contact part 23a, a first extension part 23b that is folded back to overlap with the contact part 23a, and a first extension part The heat conducting device 7 can suppress the amount of the graphene sheet 20 used in the heat conducting unit 24 by being configured with the second extending portion 23c folded back from the 23b toward the contact portion 23a, The area of the surface facing the heat generating member 2 in the heat absorbing part 23 can be ensured larger than that of the substantially sheet-like heat absorbing part.

  Further, the graphene sheet 20 absorbs heat radiated upward from the contact portion 23a of the heat absorbing portion 23 by the second extending portion 23c, and heat radiated upward from the second extending portion 23c to the first extending portion. The portion 23b can absorb heat. For this reason, compared with the case where the heat absorption part of a graphene sheet is comprised only by the contact part, the heat conductive apparatus 7 can increase the total calorie | heat amount which the heat absorption part 23 of the graphene sheet 20 absorbs heat.

  In addition, since the endothermic portion 23 can be easily configured by bending one end side of the substantially band-shaped developed shape, the heat conduction device 7 is capable of conducting heat transfer of the graphene sheet 20 formed from a sheet-like material with a high yield. It can be used as a member. Thereby, the heat conductive apparatus 7 can utilize the graphene sheet 20 which is not cheap efficiently.

  Therefore, the heat conduction device 7 can reduce the weight of the graphene sheet 20 and efficiently use the graphene sheet 20 without impairing the thermal conductivity in the in-plane direction by the heat absorption part 23 folded in the vertical direction. Can be compatible.

  In the second embodiment described above, the first extending portion 23b and the second extending portion 23c are folded back to form the heat absorbing portion 23. However, the present invention is not limited to this. For example, the second extending portion 23c is further provided. While extending, the extended portion may be folded back so as to be positioned between the first extended portion 23b and the second extended portion 23c.

  Moreover, although the part extended ahead from the heat transfer part 22 of the graphene sheet 20 was folded up and it was set as the heat absorption part 23, it is not limited to this, With respect to the contact part 23a extended ahead from the heat transfer part 22 The heat absorption part may be configured by folding the first extension part and the second extension part extending in the width direction Y from the contact part 23a.

Next, the heat conduction device 8 of Example 3 in which the shape of the graphene sheet 20 is different from the heat conduction device 1 of Example 1 described above will be described with reference to FIGS. 7 and 8.
The same configurations as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 7 is an external perspective view of the heat conducting device 8 in the third embodiment, FIG. 8 is a plan view of the graphene sheet 30 in the unfolded state, and FIG. 8 is an explanatory diagram for explaining the heat absorbing portion 33 in the third embodiment. 8A shows an external perspective view of the heat absorbing portion 33 in the unfolded state, FIG. 8B shows an external perspective view of the heat absorbing portion 33 in the first molding process, and FIG. 2 shows an external perspective view of the heat absorbing part 33 in the molding process, and FIG. 8D shows an external perspective view of the heat absorbing part 33 in the third molding process.

  Moreover, in order to clarify illustration in FIG. 7, illustration of the heat-absorbing part pressing member and the heat-radiating part pressing member is omitted. Further, in FIG. 8A, the boundary between the heat transfer part 32 and the contact part 33a of the heat absorption part 33 is indicated by a two-dot chain line L4, and the boundary between the contact part 33a and the first extension part 33b is indicated by two points. Illustrated by a chain line L5, a boundary between the contact portion 33a and the second extending portion 33c is illustrated by a two-dot chain line L6, and a boundary between the contact portion 33a and the third extending portion 33d is illustrated by a two-dot chain line L7. Yes.

  As shown in FIGS. 7 and 8A, the graphene sheet 30 of the heat conduction device 8 in Example 3 is formed in a thin film body cut out from a substantially sheet-like material into a substantially cross shape in plan view. Further, the graphene sheet 30 is formed such that a substantially T-shaped portion in plan view in a developed shape is bent into a three-dimensional shape having a height equal to or greater than the thickness of the graphene sheet 30 in the vertical direction.

  Specifically, as illustrated in FIG. 7, the graphene sheet 30 includes a heat dissipating part 31 placed on the heat dissipating member 3, a heat transfer part 32 extending forward from the heat dissipating part 31, and the heat generating member 2. The heat-absorbing part 33 that is mounted and absorbs the heat of the heat-generating member 2 is integrally formed.

  In addition, the heat conduction part 34 comprised by the heat radiating part 31 of the graphene sheet 30 and the heat transfer part 32 is the heat conduction comprised by the heat radiating part 11 and the heat transfer part 12 of the graphene sheet 10 in Example 1 mentioned above. Since it is the same structure as the part 14, the detailed description is abbreviate | omitted.

  As shown in FIG. 8A, the heat absorbing portion 33 of the graphene sheet 30 has a developed T-shape in plan view, and a contact portion 33a continuous from the front end of the heat transfer portion 32, and a contact portion 33a. A first extending portion 33b extending from the front end, a second extending portion 33c extending from the contact portion 33a in one of the width directions Y, and a second extending portion from the contact portion 33a to the other in the width direction. 3 extending portions 33d.

  Then, as shown in FIG. 7, the heat absorbing portion 33 is folded back so that the contact portion 33a, the first extending portion 33b, the second extending portion 33c, and the third extending portion 33d are folded in this order from below. Thus, it is formed in a three-dimensional shape having a height in the vertical direction.

  Note that, between the contact portion 33a and the first extension portion 33b, between the first extension portion 33b and the second extension portion 33c, and between the second extension portion 33c and the third extension portion 33d. Is filled with a heat radiation paste (not shown).

  More specifically, as shown in FIG. 7, the contact portion 33 a of the heat absorbing portion 33 is formed in a substantially rectangular shape in plan view having a size corresponding to the upper surface of the heat generating member 2. The lower surface of the contact portion 33a is indirectly in contact with the upper surface of the heat generating member 2 through a heat radiation paste (not shown).

  As shown in FIG. 7, the first extending portion 33b of the heat absorbing portion 33 extends in a substantially rectangular shape in plan view having a size substantially equal to that of the contact portion 33a. The first extending portion 33b is folded back toward the contact portion 33a so that the upper surface in the unfolded state faces the upper surface of the heat generating member 2 with the contact portion 33a interposed therebetween.

  As shown in FIG. 7, the second extending portion 33c of the heat absorbing portion 33 is a plane whose length in the front-rear direction X is slightly shorter than that of the contact portion 33a and whose length in the width direction Y is substantially equal to that of the contact portion 33a. It extends in a generally rectangular shape. The second extended portion 33c is folded back toward the first extended portion 33b so that the upper surface in the unfolded state faces the upper surface of the heat generating member 2 with the first extended portion 33b and the contact portion 33a interposed therebetween. ing.

  As shown in FIG. 7, the third extending portion 33d of the heat absorbing portion 33 has a length in the front-rear direction X substantially equal to that of the second extending portion 33c and a length in the width direction Y substantially equal to that of the contact portion 33a. Is extended in a substantially rectangular shape in plan view. The third extending portion 33d has a second extending portion so that the upper surface in the unfolded state faces the upper surface of the heat generating member 2 with the second extending portion 33c, the first extending portion 33b, and the contact portion 33a interposed therebetween. It is folded back toward the upper surface of the installation portion 33c.

Subsequently, in the graphene sheet 30 described above, the first extending portion 33b, the second extending portion 33c, and the third extending portion 33d in the unfolded state are folded to form the heat absorbing portion 33 having a height in the vertical direction. The process will be described.
In addition, the 1st extension part 33b, the 2nd extension part 33c, and the 3rd extension part 33d are each folded back using the bending jig which abbreviate | omitted illustration similarly to Example 1 mentioned above. Shall.

  First, as shown in FIGS. 8A and 8B, the first extending portion 33b of the heat absorbing portion 33 in the graphene sheet 30 cut out in a substantially cross shape in plan view is shown in FIG. It is folded upward and rearward at the position of the two-dot chain line L5 and is folded on the upper surface of the contact portion 33a.

  Further, as shown in FIGS. 8B and 8C, the second extending portion 33c is folded back at the position of the two-dot chain line L6 in FIG. 8A, and the first extending portion 33b Fold it to the top. Thereafter, as shown in FIG. 8C and FIG. 8D, the third extending portion 33d is folded at the position of the two-dot chain line L7 in FIG. Fold it to the top.

  In this way, the heat absorbing portion 33 is folded up so that the first extending portion 33b, the second extending portion 33c, and the third extending portion 33d are folded with respect to the contact portion 33a. The sheet 30 is formed in a three-dimensional shape having a height equal to or higher than the thickness.

  Since the heat conduction device 8 configured as described above can suppress the amount of the graphene sheet 30 used in the heat conduction part 34 as in the first embodiment, the heat conductivity in the in-plane direction is impaired. In addition, the weight of the graphene sheet 30 can be reduced.

  Further, the heat absorbing portion 33 of the graphene sheet 30 is in contact with the heat generating member 2 indirectly, and the first extending portion 33b and the second extending portion that are folded so as to overlap the contact portion 33a. Since the heat conducting device 8 can suppress the amount of the graphene sheet 30 used in the heat conducting part 34, the heat conducting device 2 in the heat absorbing part 33 and The area of the opposing surface can be ensured larger than that of the substantially sheet-like heat absorbing portion.

Furthermore, since each extending part is formed toward three directions in the in-plane direction in the contact part 33a, the contact part from the first extending part 33b, the second extending part 33c, and the third extending part 33d. The path reaching the heat conducting part 34 through 33a is substantially the same distance from any extending part.
In addition, the graphene sheet 30 can absorb the heat radiated upward from the contact portion 33a of the heat absorbing portion 33 by the first extending portion 33b, the second extending portion 33c, and the third extending portion 33d. .

  For this reason, the heat conduction device 8 can not only increase the total amount of heat absorbed by the endothermic portion 33 of the graphene sheet 30 as compared to the case where the endothermic portion of the graphene sheet is configured only by the contact portion, The heat absorbed by the installed portion can be efficiently conducted to the heat conducting portion 34.

Furthermore, for example, when one extended portion is folded back multiple times and folded into a contact portion, there is a possibility that lattice defects may occur in the hexagonal lattice structure in the heat absorbing portion due to multiple folding.
On the other hand, since the 1st extension part 33b, the 2nd extension part 33c, and the 3rd extension part 33d can be made to fold to the contact part 33a by the frequency | count of one folding, the heat conductive apparatus 8 Can prevent the occurrence of lattice defects in the hexagonal lattice structure in the endothermic portion 33.

  Therefore, the heat conducting device 8 has a surface by the heat absorbing portion 33 configured by folding the plurality of first extending portions 33b, second extending portions 33c, and third extending portions 33d extending in the in-plane direction. The weight reduction of the graphene sheet 30 can be achieved without impairing the thermal conductivity in the inward direction.

  In the above-described third embodiment, the first extending portion 33b, the second extending portion 33c, and the third extending portion 33d that extend in the in-plane three directions of the contact portion 33a are folded. However, the present invention is not limited to this, and the graphene sheet may be a graphene sheet configured by folding an extended portion extending in at least two directions in the in-plane direction. That's fine.

For example, it is good also as a graphene sheet which folded two extension parts extended in the width direction Y from the contact part 33a to the contact part 33a, and comprised the heat absorption part. Or it is good also as a graphene sheet which folded the three or more extended parts extended from the polygonal contact part in planar view, and comprised the heat absorption part.
Even in such a case, the same effects as those of the third embodiment described above can be obtained.

In correspondence between the configuration of the present invention and the above-described embodiment,
The graphite sheet of the present invention corresponds to the graphene sheets 10, 20, and 30 of the embodiment,
Similarly,
The thickness direction corresponds to the vertical direction,
The plurality of surfaces substantially facing the heat generating member in the thickness direction are the lower surfaces of the inclined portion 13c, the top portion 13a, and the trough portion 13b in the heat absorbing portion 13, the bottom surfaces of the top portion 16a and the trough portion 16b in the heat absorbing portion 16, and the heat absorbing portion 23. The lower surface of the contact portion 23a, the surface of the first extended portion 23b that is the upper surface in the expanded state, the surface of the second extended portion 23c that is the lower surface in the expanded state, and the lower surface of the contact portion 33a in the heat absorbing portion 33, the expanded state Corresponding to the surfaces of the first extending portion 33b, the second extending portion 33c, and the third extending portion 33d, which are upper surfaces in FIG.
The in-plane direction corresponds to the front-rear direction,
The plurality of extending portions correspond to the first extending portion 33b, the second extending portion 33c, and the third extending portion 33d,
The present invention is not limited only to the configuration of the above-described embodiment, and many embodiments can be obtained.

  For example, in the embodiment described above, the heat generating member 2 is a coil wound around the stator of the electric motor. However, the present invention is not limited to this, and any member that generates heat by the supplied energy may be used. It may be an electrical component that operates in response to the operation.

  Moreover, although the heat radiating member 3 is a housing case that houses and holds the rotor and stator in the electric motor, the heat radiating member 3 is not limited to this, and any member having good heat conductivity and heat radiating property may be used. Or a heat radiating fin.

  Further, the heat absorbing portions 13, 16, 23, and 33 of the graphene sheets 10, 20, and 30 are indirectly in contact with the heat generating member 2 through the heat radiating paste, and the heat radiating portions 11, 21, and 31 are radiated through the heat radiating paste. However, the present invention is not limited to this, and the heat absorbing portion and the heat radiating portion of the graphene sheet may be in direct contact with the heat generating member 2 and the heat radiating member 3.

  Further, although the heat conduction device using the graphene sheets 10, 20, and 30 as the heat conduction member is used, the present invention is not limited to this, and the heat conduction using the member in which the graphene sheet 10 is covered with the heat conduction film is used as the heat conduction member. It may be a device.

  Moreover, although it was set as the graphene sheet | seat 10,20,30 cut out from one raw material, it is not limited to this, The graphene sheet | seat 10,20 comprised by the laminated body which laminated | stacked the several graphene sheet cut out in the same shape , 30 may be used.

  Moreover, although the heat-absorbing parts 13, 23, and 33 in contact with the heat-generating member 2 are graphene sheets 10, 20, and 30 formed in a three-dimensional shape, the heat-dissipating part in contact with the heat-dissipating member 3 is also formed in a three-dimensional shape. It is good also as a graphene sheet. Thereby, the improvement of the thermal conductivity between the thermal radiation member 3 and the thermal radiation part of a graphene sheet can be aimed at.

  The present invention can be applied to a device that is desired to radiate the heat of the heat generating member to the outside via a heat radiating member, such as a rotating electrical machine, an inverter, or various control devices.

DESCRIPTION OF SYMBOLS 1 ... Heat conduction apparatus 2 ... Heat generating member 3 ... Heat radiating member 7 ... Heat conduction apparatus 8 ... Heat conduction apparatus 10 ... Graphene sheet 13 ... Heat absorption part 13a ... Top part 13b ... Valley part 13c ... Inclination part 14 ... Heat conduction part 16 ... Heat absorption Part 16a ... Top part 16b ... Valley part 20 ... Graphene sheet 23 ... Heat absorption part 23a ... Contact part 23b ... First extension part 23c ... Second extension part 24 ... Heat conduction part 30 ... Graphene sheet 33 ... Heat absorption part 33a ... Contact Part 33b ... 1st extension part 33c ... 2nd extension part 33d ... 3rd extension part 34 ... heat conduction part

Claims (4)

A heat generating member that generates heat by the supplied energy;
A heat radiating member for radiating the heat of the heat generating member to the outside;
A heat conduction device comprising the heat generating member and a graphite sheet that is a heat conducting member that connects the heat radiating member so as to allow heat conduction,
The graphite sheet is
An endothermic part in contact with the heat generating member directly or indirectly in the thickness direction of the graphite sheet;
The tip extended from the heat absorbing part is composed of a heat conducting part that directly or indirectly contacts the heat radiating member,
The heat conducting part is
Formed in a substantially sheet shape having a predetermined thickness,
The endothermic part is
A heat conduction device that has a plurality of surfaces substantially opposite to the heat generating member in the thickness direction and is folded into a three-dimensional shape having a length in the thickness direction equal to or greater than the thickness of the heat conduction portion. The endothermic part of the graphite sheet is
The heat conduction device according to claim 1, wherein the heat conduction device is bent into a substantially waveform shape or a substantially bellows shape continuous in an in-plane direction of the heat conduction portion. The endothermic part of the graphite sheet is
A contact portion that directly or indirectly contacts the heat generating member;
A first extending portion extending from the contact portion in an in-plane direction of the contact portion and folded back so as to overlap the contact portion;
2. The heat according to claim 1, comprising: a second extending portion that extends from the first extending portion in an in-plane direction of the first extending portion and is folded back toward the contact portion. Conduction device. The endothermic part of the graphite sheet is
A contact portion that directly or indirectly contacts the heat generating member;
The contact portion according to claim 1, wherein the contact portion extends from the contact portion in at least two directions in an in-plane direction of the contact portion and includes a plurality of extension portions each folded so as to overlap the contact portion. Heat conduction device.

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