JP7157591B2 - heatsink - Google Patents

Description

TECHNICAL FIELD The present invention relates to a heat sink for cooling a heating element, and more specifically to a heat sink for cooling electronic components mounted on moving bodies such as railway vehicles, aircraft, and automobiles, and electronic equipment.

As a conventional heat sink, a first end, a first straight portion that is a straight pipe continuing to the first end, a curved portion that is a curved pipe continuing to the first straight portion, and the curved portion a first heat pipe having a second straight portion that is a straight pipe following the first straight portion and parallel to the first straight portion; and a second end following the second straight portion; a first base having a first opposite surface of the circuit joined to the first straight portion; a flat plate perpendicular to the first straight portion and intersecting the second straight portion; a second base having a plurality of first fins provided on one surface and a second surface perpendicular to the first base and the first linear portion and joined to the first heat pipe; A heat dissipation device has been proposed that includes a plurality of second fins that are perpendicular to and provided on the second surface (Patent Document 1).

In the heat dissipation device of Patent Document 1, in addition to a first heat sink having a plurality of first fins, a second heat sink having a plurality of second fins arranged perpendicular to the first heat sink is also provided. It improves heat radiation efficiency.

However, in the heat dissipation device of Patent Document 1, since the flat first fins are arranged in parallel at a predetermined interval, a boundary layer is formed on the surface of the first fins in which the flow of the cooling air is stagnant. However, there is a problem that the heat radiation characteristic is degraded at the portion on the leeward side of the surface of the first fin.

Also, in the case of a heat sink in which a plate-like heat dissipation fin is attached to a U-shaped heat pipe when viewed from the side, and the heat pipe is installed so that the U-shape is parallel to the cooling air, the heat sink is located between the straight portions of the U-shape. Among the parts of the heat radiation fins, the vicinity of the central part thereof is far from the straight part of the heat pipe, so there is a problem that the heat radiation efficiency of the heat radiation fins is lowered.

JP 2011-94888 A

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a heat sink that suppresses the formation of a boundary layer on the surfaces of heat radiating fins and has excellent heat radiating performance even at portions other than the windward side of the cooling air.

Aspects of the present invention include a base plate, at least one first heat dissipation fin thermally connected to the base plate, adjacent to a side edge of the first heat dissipation fin and thermally connected to the base plate. and at least one second heat radiating fin, wherein the surface of the first heat radiating fin is not parallel to the surface of the second heat radiating fin but perpendicular to the surface of the base plate. At least one of the second heat radiation fins is a heat sink provided at a position lower than at least one of the first heat radiation fins.

In the above aspect, at least one of the second heat radiation fins is provided at a position lower than at least one of the first heat radiation fins, that is, at a position closer to the base plate. Further, in the above aspect, the surface of the first heat radiation fin and the surface of the second heat radiation fin are arranged in a state not parallel to each other. It is arranged at an angle of more than 0° and less than or equal to 90° with respect to the surface of the fin. Therefore, when the cooling air is supplied from the first heat radiation fin side or the second heat radiation fin side, turbulence occurs in the flow of the cooling air between the first heat radiation fins and the second heat radiation fins.

According to an aspect of the present invention, a plurality of the second heat radiation fins are arranged along the surface of the base plate to form a second heat radiation fin group, and the second heat radiation fin group is arranged at least in the center of the second heat radiation fin group. The second heat radiation fin is a heat sink provided at a position lower than at least one of the first heat radiation fins.

An aspect of the present invention is a heat sink in which the second heat radiating fins are thermally connected to the base plate by being in contact with the base plate at their lower ends.

Aspects of the present invention include a base plate, at least one first heat dissipation fin thermally connected to the base plate, adjacent to a side edge of the first heat dissipation fin and thermally connected to the base plate. and at least one second heat radiating fin, wherein the surface of the first heat radiating fin is not parallel to the surface of the second heat radiating fin but perpendicular to the surface of the base plate. At least one of the second heat radiating fins is provided at a position lower than at least one of the first heat radiating fins, and the free end of the second heat radiating fin faces the lower end of the second heat radiating fin. It is a heat sink provided with a shielding member that shields it from the environment.

An aspect of the present invention is a heat sink in which the first heat radiation fins are thermally connected to the base plate via a heat conducting member.

A "thermally conductive member" is a member having excellent thermal conductivity, and includes heat pipes and metals (eg, aluminum, copper, etc.) having a thermal conductivity of 100 W/(m·K) or more at 25°C.

Aspects of the present invention further include at least one third heat dissipating fin thermally connected to the base plate adjacent to the side edge of the second heat dissipating fin, the surface of the third heat dissipating fin is a heat sink that is not parallel to the surface of the second heat radiating fins.

In the above aspect, the surface of the second heat radiating fin and the surface of the third heat radiating fin are arranged in a non-parallel manner. It is arranged at an angle of more than 0° and less than or equal to 90° with respect to the surface. Therefore, when cooling air is supplied from the side of the third radiating fin or the side of the first radiating fin, turbulence occurs in the flow of the cooling air between the second radiating fin and the third radiating fin.

An aspect of the present invention is the heat sink, wherein at least one of the second heat dissipating fins is provided at a position lower than at least one of the third heat dissipating fins in a direction perpendicular to the surface of the base plate.

In the above aspect, at least one of the second heat radiation fins is provided closer to the base plate than at least one of the third heat radiation fins.

An aspect of the present invention is a heat sink in which the third heat dissipating fins are thermally connected to the base plate via a heat conducting member.

An aspect of the present invention is a heat sink in which the heat conducting member is a heat pipe.

An aspect of the present invention is a heat sink in which the shape of the heat pipe is U-shaped when viewed from the side, L-shaped when viewed from the side, or U-shaped when viewed from the side.

According to the aspect of the present invention, since at least one of the second heat radiation fins is provided at a position lower than at least one of the first heat radiation fins, the heat density of the second heat radiation fins is improved. , the second heat-dissipating fins exhibit excellent heat-dissipating efficiency. Furthermore, since at least one of the second heat radiation fins is provided at a position lower than at least one of the first heat radiation fins, the air flows through the second heat radiation fins and the downwind side of the second heat radiation fins. Cooling air pressure loss is reduced. Therefore, in the aspect of the present invention, excellent heat dissipation performance can be exhibited even at a portion other than the windward side of the cooling air. Moreover, according to the aspect of the present invention, at least one of the second heat radiation fins is provided at a position lower than at least one of the first heat radiation fins, so that the weight of the heat sink can be reduced.

Further, according to the aspect of the present invention, since the surface of the first heat radiation fin and the surface of the second heat radiation fin are arranged in a state not parallel to each other, Since the formation of a boundary layer between the first and second heat radiating fins is suppressed when the cooling air is supplied from the 2 heat radiating fins, the heat radiating efficiency of the heat radiating fins can be prevented from decreasing. Furthermore, the flow of the cooling air is disturbed between the first and second radiating fins, that is, the cooling air is agitated, so that the heat transfer rate between the fins and the cooling air can be improved. .

According to the aspect of the present invention, the second heat radiation fins arranged at least in the central portion of the second heat radiation fin group are provided at a position lower than at least one of the first heat radiation fins, Since the cooling air supplied to the heat sink can flow more efficiently to the leeward side of the second heat radiation fin group, the heat radiation performance is further improved.

According to the aspect of the present invention, the shielding member is further provided on the free end side of the second heat radiating fins, so that the cooling air supplied to the heat sink is directed to the outside from the free ends of the second heat radiating fins. Since it is possible to prevent the cooling air from flowing out, the cooling air can be efficiently circulated to the leeward side of the second heat radiation fin group, and as a result, the heat radiation performance is further improved.

According to the aspect of the present invention, further comprising a third heat radiation fin adjacent to the side edge side of the second heat radiation fin, the surface of the second heat radiation fin and the surface of the third heat radiation fin are mutually In addition, since they are arranged in a non-parallel state, when supplying the cooling air from the first or third heat radiation fin side, only between the first heat radiation fin and the second heat radiation fin In addition, since the formation of the boundary layer is also suppressed between the second heat radiating fin and the third heat radiating fin, it is possible to further prevent the deterioration of the heat radiation efficiency of the heat radiating fins. Furthermore, the flow of cooling air is disturbed not only between the first and second heat radiation fins, but also between the second and third heat radiation fins. can further improve the heat transfer coefficient of

1 is a perspective view of a heat sink according to a first embodiment of the invention; FIG. 1 is a front view of a heat sink according to a first embodiment of the invention; FIG. FIG. 5 is a perspective view of a heat sink according to a second embodiment of the invention; FIG. 11 is a perspective view of a heat sink according to a third embodiment of the invention; FIG. 11 is a perspective view of a heat sink according to a fourth embodiment of the invention; FIG. 11 is a perspective view of a heat sink according to a fifth embodiment of the present invention; FIG. 11 is a perspective view of a heat sink according to a sixth embodiment of the present invention; FIG. 21 is a perspective view of a heat sink according to a seventh embodiment of the present invention; FIG. 21 is a perspective view of a heat sink according to an eighth embodiment of the present invention;

A heat sink according to a first embodiment of the present invention will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, the heat sink 1 according to the first embodiment includes a flat plate-shaped base plate 10 thermally connected to a heating element (not shown) to be cooled on the back side, and a base plate 10 A heat pipe 14 erected in the surface side direction, a first heat radiation fin 11 thermally connected to the base plate 10 via the heat pipe 14, a side end portion of the first heat radiation fin 11 and the first heat radiation fin 11 second heat radiation fins 12 adjacent to each other with a gap 15 therebetween; there is

The second heat radiation fins 12 are thermally connected to the base plate 10 by being in direct contact with the front surface of the base plate 10 . The third heat radiation fins 13 are thermally connected to the base plate 10 via heat pipes 14 .

A first heat radiation fin group 17 is formed from the plurality of first heat radiation fins 11 , a second heat radiation fin group 18 is formed from the plurality of second heat radiation fins 12 , and a third heat radiation fin group is formed from the plurality of third heat radiation fins 13 . Three radiation fin groups 17 are formed. Also, the first heat radiation fin group 17, the second heat radiation fin group 18, and the third heat radiation fin group 19 are mutually arranged linearly on the base plate 10. As shown in FIG.

In the heat sink 1, the first heat radiation fins 11 are flat. A plurality of first heat radiation fins 11 are arranged substantially vertically with respect to the surface of the base plate 10 at approximately equal intervals. A first radiation fin group 17 is formed so as to be arranged substantially parallel to each other. That is, the first radiation fin group 17 is provided on the surface of the base plate 10 with a predetermined height dimension, and the fin pitches of the first radiation fin group 17 are approximately equal. Therefore, a first space 11 ′ having a constant width extends substantially parallel to the surface of the base plate 10 between the respective first radiation fins 11 .

In the heat sink 1 , a plurality of (two in the figure) heat pipes 14 are erected substantially parallel and parallel in the surface side direction of the base plate 10 . The shape of the heat pipe 14 is U-shaped when viewed from the side. Therefore, the U-shaped heat pipe 14 when viewed from the side has two straight portions facing each other, that is, one straight portion 14a and the other straight portion 14b. It has a bottom portion 14c between it and 14b.

The bottom portion 14 c of the U-shaped heat pipe 14 in side view is in direct contact with the base plate 10 , so that the U-shaped heat pipe 14 in side view is thermally connected to the base plate 10 . In the heat sink 1, the bottom portion 14c of the U-shaped heat pipe 14 when viewed from the side is fitted into a groove (not shown) formed on the back side of the base plate 10, thereby forming the U-shaped heat pipe 14 when viewed from the side. are thermally connected to the base plate 10 .

The first heat radiation fin 11 is attached to one linear portion 14a of the U-shaped heat pipe 14 when viewed from the side. The first heat dissipating fin 11 is in direct contact with one straight portion 14a of the U-shaped heat pipe 14 when viewed from the side, so that the first heat dissipating fin 11 is thermally connected to the U-shaped heat pipe 14 when viewed from the side. Furthermore, the first heat radiation fins 11 are thermally connected to the base plate 10 via a U-shaped heat pipe 14 when viewed from the side. Therefore, the first heat radiation fin group 17 is arranged on one end side of the heat sink 1 .

A second heat radiating fin 12 is arranged on the surface side of the base plate 10 in a region where the bottom portion 14 c of the heat pipe 14 having a U shape in side view is attached, that is, in the central portion of the heat sink 1 . The second radiation fins 12 are flat, and their lower ends are attached to the surface of the base plate 10 . The lower ends of the second heat radiation fins 12 are in direct contact with the base plate 10 , so that the second heat radiation fins 12 are thermally connected to the base plate 10 . The end of the second heat radiation fin 12 facing the lower end, that is, the tip is a free end.

The method of attaching the second heat radiation fins 12 to the surface side of the base plate 10 is not particularly limited. A method of fitting into a concave groove formed on the surface side of the .

In the heat sink 1, a plurality of second heat radiation fins 12 are arranged along the surface of the base plate 10 at approximately equal intervals. A single second radiation fin group 18 is formed so as to be arranged substantially vertically with respect to them. Each of the second heat radiation fins 12 is arranged so as to be substantially parallel to the arrangement direction of the first heat radiation fin group 17, the second heat radiation fin group 18, and the third heat radiation fin group 19. ing. The fin pitches of the second radiation fin group 18 are substantially equal. Therefore, a second space 12 ′ having a constant width extends substantially vertically with respect to the surface of the base plate 10 between the respective second radiation fins 12 .

Since the second heat radiation fins 12 are arranged in the region where the bottom portion 14c of the heat pipe 14 having a U shape in side view is attached, the second heat radiation fin group 18 is arranged in the central portion of the heat sink 1. there is Also, the second heat radiation fins 12 are arranged such that the second space 12 ′ formed between the second heat radiation fins 12 faces the first space 11 ′ formed between the first heat radiation fins 11 . are placed in The side end portion of the first heat radiation fin 11 on the side of the second heat radiation fin group 18 and the side end portion of the second heat radiation fin 12 on the side of the first heat radiation fin group 17 are separated by the first gap 15 . facing each other.

Since the lower end of the second heat radiation fins 12 is in direct contact with the surface side of the base plate 10, when a heating element is thermally connected to the back side of the central portion of the base plate 10, the base plate of the second heat radiation fins 12 is 10 side, namely the bottom side of the second heat dissipating fins 12, heat is transferred to the opposite side of the base plate 10, namely the free end side of the second heat dissipating fins 12, so that the second heat dissipating fins 12 can achieve the desired heat dissipation. Effective.

Further, as shown in FIGS. 1 and 2, the height of the second heat radiation fins 12 from the surface of the base plate 10 is lower than the height of the first heat radiation fin group 17 from the surface of the base plate 10 . That is, the free ends of the second heat radiation fins 12 are positioned lower than the height of the first heat radiation fin group 17 from the surface of the base plate 10 . Therefore, the free end of the second heat dissipating fin 12 is positioned closer to the base plate 10 than at least the uppermost first heat dissipating fin 11 among the plurality of first heat dissipating fins 11 constituting the first heat dissipating fin group 17 . located on the side. The "height of the first heat radiation fin group 17 from the surface of the base plate 10" is the dimension between the surface of the base plate 10 and the first heat radiation fin 11 positioned at the top of the first heat radiation fin group 17. means Also, the “height of the second radiation fins 12 from the surface of the base plate 10 ” means the dimension between the surface of the base plate 10 and the free ends of the second radiation fins 12 .

At least one of the plurality of second heat radiation fins 12 should be lower than the height of the first heat radiation fin group 17 from the surface of the base plate 10, and is lower than the height of the first heat radiation fin group 17 from the surface of the base plate 10. Although the number of low second heat radiation fins 12 is not particularly limited, in the heat sink 1, all of the plurality of second heat radiation fins 12 are lower than the height of the first heat radiation fin group 17 from the surface of the base plate 10. It has become. Further, in the heat sink 1, the heights of the plurality of second heat radiation fins 12 from the surface of the base plate 10 are substantially the same. Therefore, in the heat sink 1 , the height of the second radiation fin group 18 from the surface of the base plate 10 is lower than the height of the first radiation fin group 17 from the surface of the base plate 10 .

Since the height of the second heat radiation fins 12 from the surface of the base plate 10 is lower than the height of the first heat radiation fin group 17 from the surface of the base plate 10, the second heat radiation fin group 18 and the second heat radiation fins The pressure loss of the cooling air flowing downwind of the group 18 can be reduced. Therefore, the heat sink 1 can exhibit excellent heat dissipation performance even at a portion on the leeward side of the cooling air from the second heat dissipation fin group 18 . Further, since the height of the second radiation fins 12 from the surface of the base plate 10 is lower than the height of the first radiation fin group 17 from the surface of the base plate 10, the heat density of the second radiation fins 12 is improved. As a result, the heat dissipation efficiency per unit area of the second heat dissipation fins 12 is improved. Furthermore, the height of the second radiation fins 12 from the surface of the base plate 10 is lower than the height of the first radiation fin group 17 from the surface of the base plate 10, so that the weight of the heat sink 1 can be reduced.

The ratio of the height of the second radiation fins 12 from the surface of the base plate 10 to the height of the first radiation fin group 17 from the surface of the base plate 10, that is, the uppermost part of the first radiation fin group 17 from the surface of the base plate 10 The ratio of the height of the second heat radiation fins 12 from the surface of the base plate 10 to the dimension up to the first heat radiation fins 11 located at the pressure loss of the cooling air flowing on the leeward side of the second heat radiation fin group 18 0.20 to 0.80 is preferable, 0.30 to 0.70 is more preferable, and 0.35 to 0.60 is particularly preferable from the viewpoint of the balance between the reduction of .

As shown in FIG. 2, the surface of the second heat radiating fins 12 is provided substantially perpendicular to the surface of the first heat radiating fins 11, so that the first heat radiating fins 11 and the second heat radiating fins 12 are They are arranged in a grid pattern when viewed from the front. Also, the direction in which the first space 11' formed between the first heat radiation fins 11 extends is substantially orthogonal to the direction in which the second space 12' formed between the second heat radiation fins 12 extends. direction. Moreover, since the height of the second heat radiation fins 12 from the surface of the base plate 10 is lower than the height of the first heat radiation fin group 17 from the surface of the base plate 10 , the upper portion of the free end of the second heat radiation fins 12 is , the second heat radiating fins 12 are not present, and the first heat radiating fins 11 and the second heat radiating fins 12 are not arranged in a grid pattern.

In FIG. 2, in order to improve the thermal connectivity between the heating element installed in the central portion of the base plate 10 and the U-shaped heat pipe 14 when viewed from the side, the bottom portion of the U-shaped heat pipe 14 when viewed from the side is 14 c is curved toward the central portion of the base plate 10 .

As shown in FIG. 1, the third heat radiation fin 13, which is a flat plate-shaped heat radiation fin, is attached to the other straight portion 14b of the heat pipe 14 which is U-shaped when viewed from the side. Accordingly, a third heat radiation fin 13 is arranged on the other end side of the heat sink 1 . The third heat dissipating fin 13 is in direct contact with the other straight portion 14b of the U-shaped heat pipe 14 when viewed from the side, so that the third heat dissipating fin 13 is thermally connected to the U-shaped heat pipe 14 when viewed from the side. Furthermore, the third heat radiating fins 13 are thermally connected to the base plate 10 via a U-shaped heat pipe 14 when viewed from the side.

In the heat sink 1, a plurality of third heat radiation fins 13 are arranged substantially vertically with respect to the surface of the base plate 10 at approximately equal intervals. A single third radiation fin group 19 is formed so as to be arranged substantially parallel to the surface. That is, the third heat radiation fin group 19 is provided on the surface of the base plate 10 with a predetermined height dimension, and the fin pitch of the third heat radiation fin group 19 is approximately equal. Therefore, third spaces 13 ′ of constant width extend substantially parallel to the surface of the base plate 10 between the respective third heat radiation fins 13 .

Since the third heat radiation fins 13 are provided on the other end side of the heat sink 1 , the third heat radiation fin group 19 is arranged on the other end side of the heat sink 1 . Further, the third heat radiation fins 13 are arranged so that the third space 13 ′ formed between the third heat radiation fins 13 faces the second space 12 ′ formed between the second heat radiation fins 12 . are placed in The side end portion of the second heat radiation fin 12 on the side of the third heat radiation fin group 19 and the side end portion of the third heat radiation fin 13 on the side of the second heat radiation fin group 18 are separated from each other with the second gap 16 therebetween. facing each other.

As shown in FIG. 1, the height of the second radiation fins 12 from the surface of the base plate 10 is lower than the height of the third radiation fin group 19 from the surface of the base plate 10 . Therefore, the free end of the second heat dissipating fin 12 is positioned closer to the base plate 10 than at least the third heat dissipating fin 13 positioned at the top among the plurality of third heat dissipating fins 13 constituting the third heat dissipating fin group 19 . located on the side. Further, in the heat sink 1, the height of the third radiation fin group 19 from the surface of the base plate 10 is substantially the same as the height of the first radiation fin group 17 from the surface of the base plate 10. As shown in FIG. The "height of the third heat radiation fin group 19 from the surface of the base plate 10" is the dimension between the surface of the base plate 10 and the third heat radiation fin 13 positioned at the top of the third heat radiation fin group 19. means

In the heat sink 1, the pressure loss of the cooling air flowing through the second heat radiation fin group 18 and the downwind side of the second heat radiation fin group 18 can be reduced. The third heat dissipating fin group 19, which can be the part of (1), can also exhibit excellent heat dissipating performance.

Since the surface of the third heat radiating fin 13 is provided in a direction substantially perpendicular to the surface of the second heat radiating fin 12, the second heat radiating fin 12 and the third heat radiating fin 13 are arranged in a grid pattern when viewed from the rear. are placed. Further, the extending direction of the second space 12' formed between the second heat radiating fins 12 is substantially orthogonal to the extending direction of the third space 13' formed between the third heat radiating fins 13. direction. Moreover, since the height of the second heat radiation fins 12 from the surface of the base plate 10 is lower than the height of the third heat radiation fin group 19 from the surface of the base plate 10 , the upper portion of the free end of the second heat radiation fins 12 is , the third radiating fins 13 and the second radiating fins 12 are not arranged in a grid pattern.

Furthermore, the surface of the third heat dissipating fins 13 is provided substantially parallel to the surface of the first heat dissipating fins 11 . Further, the extending direction of the third space 13' formed between the third heat dissipating fins 13 and the extending direction of the first space 11' formed between the first heat dissipating fins 11 are substantially parallel. ing.

The first heat radiation fin 11, the second heat radiation fin 12, the third heat radiation fin 13, and the base plate 10 are all flat plates made of a metal material with good thermal conductivity, such as aluminum, aluminum alloy, copper, or copper alloy. manufactured. The container material of the U-shaped heat pipe 14 in side view is also made of the same metal material as the first heat radiation fin 11 , the second heat radiation fin 12 , the third heat radiation fin 13 and the base plate 10 . As the working fluid of the U-shaped heat pipe 14 when viewed from the side, a fluid compatible with a container, which is a closed container, is sealed in a decompressed state. Examples of working fluids include water, CFC substitutes, perfluorocarbons, cyclopentane, and the like.

The cooling air is directed substantially parallel to the arrangement direction of the first heat radiation fin group 17, the second heat radiation fin group 18, and the third heat radiation fin group 19 and the surface of the base plate 10. The cooling air is supplied to the heat sink 1 from the 17 side or the third radiating fin group 19 side. In FIG. , is fed from one end of the heat sink 1 toward the other end. In the heat sink 1, formation of a boundary layer between the first heat radiation fin 11 and the second heat radiation fin 12 and between the second heat radiation fin 12 and the third heat radiation fin 13 is suppressed. It is possible to prevent the deterioration of the heat radiation efficiency. Furthermore, since the cooling air is agitated between the first heat radiation fins 11 and the second heat radiation fins 12 and between the second heat radiation fins 12 and the third heat radiation fins 13, Heat transfer coefficient can be improved.

Further, as shown in FIGS. 1 and 2, the first heat radiating fins 11 are attached to the curved portion between one straight portion 14a and the bottom portion 14c of the U-shaped heat pipe 14 when viewed from the side. The third heat radiation fin 13 is not attached to the curved portion between the other straight portion 14b and the bottom portion 14c. Therefore, the cooling air is smoothly supplied to the bottom side of the second heat radiation fin 12 and its vicinity.

Furthermore, in the heat sink 1, the formation of a boundary layer is suppressed, and a decrease in the heat dissipation efficiency of the heat dissipation fins between the straight portion 14a on one side and the straight portion 14b on the other side of the heat pipe 14 can be prevented. As a result, the thermal resistance between the base plate 10 and the U-shaped heat pipe 14 when viewed from the side can be reduced.

Next, a heat sink according to a second embodiment of the invention will be described with reference to the drawings. The same components as those of the heat sink according to the first embodiment will be described using the same reference numerals.

As shown in FIG. 3 , the heat sink 2 according to the second embodiment further includes a shielding member 60 at the portion of the second radiation fin group 18 . In the heat sink 2 , both lateral side portions of the second heat radiation fin group 18 and free ends of the second heat radiation fins 12 are covered with shielding members 60 . Therefore, both lateral side portions of the second radiation fin group 18 and the free ends of the second radiation fins 12 are shielded from the external environment by the shielding member 60 . On the other hand, the side end portion of the second heat radiation fin group 18 on the first heat radiation fin group 17 side and the side end portion on the third heat radiation fin group 19 side are both covered with the shield member 60 . It is open.

In the heat sink 2, the shielding member 60 is a U-shaped member composed of three plane portions when viewed from the front. By covering the second heat radiation fin group 18 with the shielding member 60, both lateral side portions of the second heat radiation fin group 18 and the free ends of the second heat radiation fins 12 are shielded from the external environment. The height of the shield member 60 is substantially the same as the height of the first radiation fin group 17 from the surface of the base plate 10 and the height of the third radiation fin group 19 from the surface of the base plate 10 .

Examples of the material of the shielding member 60 include metal materials with good thermal conductivity, such as aluminum, aluminum alloys, copper, and copper alloys.

The height of the second radiation fin group 18 from the surface of the base plate 10 is lower than the height of the first radiation fin group 17 from the surface of the base plate 10 and the height of the third radiation fin group 19 from the surface of the base plate 10. Therefore, the shielding member 60 can prevent the cooling air from flowing out of the heat sink 2 from both lateral side portions and free ends of the second heat radiation fin group 18 . Therefore, the cooling air can be efficiently supplied to the leeward side of the second heat radiation fin group 18, and as a result, the heat radiation performance of the heat sink 2 is further improved.

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

In the heat sink 1 according to the first embodiment, all of the plurality of second heat radiation fins 12 have substantially the same height, but instead of this, as shown in FIG. In the heat sink 3 according to this embodiment, only the second heat radiation fins 12 arranged in the central portion of the second heat radiation fin group 18 are lower than the height of the first heat radiation fin group 17 from the surface of the base plate 10. there is That is, the second heat radiation fins 12 arranged at the center in the arrangement direction of the second heat radiation fins 12 are lower than the height of the first heat radiation fin group 17 from the surface of the base plate 10, and the height of the second heat radiation fins 12 The second heat radiation fins 12 arranged at the ends in the arrangement direction (that is, the ends of the second heat radiation fin group 18) have substantially the same height as the height of the first heat radiation fin group 17 from the surface of the base plate 10. have.

The second heat radiating fins 12 arranged at the center of the second heat radiating fin group 18 with respect to the height of the second heat radiating fins 12 arranged at the ends of the second heat radiating fin group 18 from the surface of the base plate 10 . from the surface of the base plate 10 is 0.00, from the viewpoint of the balance between the reduction in the pressure loss of the cooling air flowing on the leeward side of the second radiation fin group 18 and the heat dissipation characteristics of the second radiation fins 12 . 20 to 0.80 is preferred, 0.30 to 0.70 is more preferred, and 0.35 to 0.60 is particularly preferred.

In the heat sink 3 as well, the pressure loss of the cooling air flowing through the second heat radiation fin group 18 and the downwind side of the second heat radiation fin group 18 can be reduced. The third heat dissipating fin group 19, which can be the part of (1), can also exhibit excellent heat dissipating performance.

Next, a heat sink according to a fourth embodiment of the invention will be described with reference to the drawings. The same components as those of the heat sinks according to the first to third embodiments will be described using the same reference numerals.

As shown in FIG. 5, in the heat sink 4 according to the fourth embodiment, a shielding member 60 is further provided at the second radiation fin group 18 of the heat sink 3 according to the third embodiment. It has become. In the heat sink 4 , free ends of the second heat radiation fins 12 are covered with the shielding member 60 . Therefore, the free ends of the second radiation fin group 18 are shielded from the external environment by the shielding member 60 . On the other hand, the side end portion on the first heat radiation fin group 17 side, the side end portion on the third heat radiation fin group 19 side, and both lateral side portions of the second heat radiation fin group 18 are all covered with shielding members 60. not covered with

In the heat sink 4, the shielding member 60 is a flat member. By placing the shielding member 60 on the free end of the second heat radiating fin 12 arranged at the end of the second heat radiating fin group 18, the free end of the second heat radiating fin 12 is shielded from the external environment. . In the heat sink 4 , the shape and dimensions of the shielding member 60 in plan view are substantially the same as those of the second radiation fin group 18 in plan view.

The height of the second heat radiation fins 12 arranged in the center of the second heat radiation fin group 18 from the surface of the base plate 10 is equal to the height of the first heat radiation fin group 17 from the surface of the base plate 10 and the height of the third heat radiation fin group 17 from the surface of the base plate 10 Since the height of the fin group 19 from the surface of the base plate 10 is lower than that of the base plate 10 , the cooling air flows outward from the heat sink 4 from the free end at the center of the second heat radiation fin group 18 . The outflow of wind can be prevented. Therefore, cooling air can be efficiently supplied to the downwind side of the second heat radiation fin group 18, and as a result, the heat radiation performance of the heat sink 4 is further improved.

Next, a heat sink according to a fifth embodiment of the invention will be described with reference to the drawings. The same components as those of the heat sinks according to the first to fourth embodiments will be described using the same reference numerals.

As shown in FIG. 6, in the heat sink 5 according to the fifth embodiment, instead of the U-shaped heat pipe 14 in side view used in the heat sink 4 according to the fourth embodiment, A heat pipe 24 is used. The U-shaped heat pipe 24 when viewed from the side has two straight portions facing each other, that is, a top side straight portion 24a and a bottom side straight portion 24b. It has a linear side portion 24c between. The heat sink 5 is provided with a plurality of (four in the drawing) heat pipes 24 that are U-shaped when viewed from the side. In addition, two U-shaped heat pipes 24 in a side view are erected substantially parallel and side by side in the surface side direction of the base plate 10, and are arranged to face each other. Therefore, the side portion 24 c is not erected at the central portion of the heat sink 5 , but is erected at one end and the other end of the heat sink 5 .

The U-shaped heat pipe 24 is thermally connected to the base plate 10 by directly contacting the bottom straight portion 24b of the U-shaped heat pipe 24 in side view with the base plate 10 . In the heat sink 5, the bottom straight portion 24b of the heat pipe 24, which is U-shaped when viewed from the side, is fitted into a groove (not shown) formed on the back side of the base plate 10, thereby forming a U-shaped when viewed from the side. A heat pipe 24 is thermally connected to the base plate 10 .

A plurality of first radiation fins 11 are attached to a side portion 24c erected on one end of the heat sink 5 to form a first radiation fin group 17. As shown in FIG. A plurality of third heat radiation fins 13 are attached to a side portion 24c erected on the other end of the heat sink 5 to form a third heat radiation fin group 19. As shown in FIG.

Further, in the second heat radiation fin group 18 formed by attaching a plurality of second heat radiation fins 12, the free end of the second heat radiation fin 12 arranged at the end of the second heat radiation fin group 18 is , is thermally connected to the top straight portion 24a of the heat pipe 24, which is U-shaped when viewed from the side, via a flat shielding member 60. As shown in FIG. Accordingly, the free ends of the second heat radiation fins 12 arranged at the ends of the second heat radiation fin group 18 are thermally connected to the base plate 10 via the U-shaped heat pipes 24 when viewed from the side.

In the heat sink 5, heat transmitted from a heating element (not shown) to the base plate 10 is not only transmitted from the base plate 10 to the bottom side of the second heat radiation fin group 18, but also is transmitted by the U-shaped heat pipe 24 when viewed from the side. It is also transported from the base plate 10 to the free end side of the second radiation fin group 18 . Therefore, even with the second heat dissipating fin group 18 having the second heat dissipating fins 18 with a small fin area, excellent heat dissipating performance can be obtained.

Next, a heat sink according to a sixth embodiment of the invention will be described with reference to the drawings. The same components as those of the heat sinks according to the first to fifth embodiments will be described using the same reference numerals.

In the heat sink 1 according to the first embodiment, the surfaces of the third heat radiation fins 13 are arranged substantially parallel to the surface of the base plate 10. Instead of this, as shown in FIG. In the heat sink 6 according to the sixth embodiment, the third space 33' formed between the third heat dissipating fins 33 faces the second space 12' formed between the second heat dissipating fins 12. However, the surfaces of the third heat radiation fins 33 are arranged so as not to be parallel to the surface of the base plate 10 . In the third heat dissipating fin 33 of the heat sink 6, the side end 33-1 on the side facing the second heat dissipating fin group 18 is positioned further than the side end 33-2 on the side opposite to the side end 33-1. A higher position, that is, the side end portion 33-2 of the third heat radiation fin 33 is positioned closer to the base plate 10 than the side end portion 33-1.

The angle of the surface of the third heat radiation fins 33 with respect to the surface of the base plate 10 is not particularly limited. is about 30°.

In the heat sink 6 , a plurality of third heat radiation fins 33 are arranged substantially vertically with respect to the surface of the base plate 10 at substantially equal intervals to form one third heat radiation fin group 39 . The third heat dissipating fin group 39 is provided on the surface of the base plate 10 with a predetermined height dimension, and the fin pitch of the third heat dissipating fin group 39 is approximately equal. A constant-width third space 33 ′ formed between the respective third radiation fins 33 extends toward the surface side of the base plate 10 as the distance from the second radiation fin group 18 increases. The heat sink 6 is provided with five U-shaped heat pipes 14 when viewed from the side. The U-shaped heat pipes 14 in side view include two types of heat pipes 14-1 having a long bottom portion 14c and U-shaped heat pipes 14-2 having a short bottom portion 14c. A long U-shaped heat pipe 14-1 on the bottom portion 14c and a short U-shaped heat pipe 14-2 on the bottom portion 14c are erected substantially parallel and side by side so as to be adjacent to each other. It is Accordingly, one linear portion 14a of the heat pipe 14 is arranged in a staggered manner, and the other linear portion 14b is also arranged in a staggered manner.

The third space 33 ′ extends toward the surface side of the base plate 10 as it separates from the second radiation fin group 18 . Therefore, when cooling air is supplied from the first heat radiation fin group 17 side toward the third heat radiation fin group 39 and a short member to be cooled is arranged on the leeward side of the heat sink 6, the base plate 10 is heated. Not only the thermally connected heating element (not shown) but also a short member to be cooled arranged on the lee side of the heat sink 6 can be cooled by the cooling air flowing through the heat sink 6 .

Next, a heat sink according to a seventh embodiment of the present invention will be described with reference to the drawings. The same components as those of the heat sinks according to the first to sixth embodiments will be described using the same reference numerals.

As shown in FIG. 8, in the heat sink 7 according to the seventh embodiment, an L-shaped heat pipe 44 in side view is used instead of the U-shaped heat pipe 14 in side view. Therefore, the heat sink 7 does not have the third heat radiation fin group unlike the above embodiments. In addition, the surface of the second heat radiation fins 12 of the heat sink 1 according to the first embodiment is aligned with respect to the arrangement direction of the first heat radiation fin group 17, the second heat radiation fin group 18, and the third heat radiation fin group 19. In the heat sink 7 according to the seventh embodiment, the second space formed between the second heat radiating fins 42 instead of the second heat radiating fins 12 being arranged so as to be substantially parallel to each other. While 42 ′ faces the first space 11 ′ formed between the first heat radiating fins 11 , the surface of the second heat radiating fins 42 is formed between the first heat radiating fin group 17 and the second heat radiating fin group. 48 are positioned in a direction that is not parallel to the alignment direction.

The angle of the surfaces of the second heat radiation fins 42 with respect to the arrangement direction is not particularly limited. is about 30°.

In the heat sink 7 , a plurality of (two in the figure) L-shaped heat pipes 44 in a side view are erected substantially in parallel in the direction of the surface of the base plate 10 . The L-shaped heat pipe 44 when viewed from the side has one linear portion 44a and one bottom portion 44c.

The bottom portion 44 c of the L-shaped heat pipe 44 in side view is in direct contact with the base plate 10 , so that the L-shaped heat pipe 44 in side view is thermally connected to the base plate 10 . In the heat sink 7, the bottom portion 44c of the L-shaped heat pipe 44 when viewed from the side is fitted into a groove (not shown) formed on the back side of the base plate 10, whereby the L-shaped heat pipe 44 when viewed from the side is fitted. are thermally connected to the base plate 10 .

The first heat radiating fin 11 is attached to a linear portion 44a of an L-shaped heat pipe 44 when viewed from the side. The first heat radiation fin group 17 is formed by attaching a plurality of the first heat radiation fins 11 to the linear portion 44a of the L-shaped heat pipe 44 when viewed from the side. In the heat sink 7 , the first heat radiation fin group 17 is arranged from the central portion of the heat sink 7 to one end portion.

Also, in the heat sink 7 , each of the second heat radiating fins 42 is provided such that its surface is substantially perpendicular to the surface of the base plate 10 . The second radiation fin group 48 is arranged from the central portion of the heat sink 7 to the other end portion.

In the heat sink 7 as well, the height of the second heat radiation fins 42 from the surface of the base plate 10 is lower than the height of the first heat radiation fin group 17 from the surface of the base plate 10 . The pressure loss of the cooling air flowing on the leeward side of the radiation fin group 48 can be reduced. Therefore, when the cooling air is supplied from the first heat radiation fin group 17 side toward the second heat radiation fin group 48 and the member to be cooled is arranged on the oblique leeward side of the heat sink 7, the base plate 10 is thermally cooled. Not only the connected heating element (not shown) but also the member to be cooled arranged on the oblique leeward side of the heat sink 7 can be cooled by the cooling air.

Further, even if the number of heat radiation fin groups is two and the surface of the second heat radiation fin 42 is not substantially parallel to the arrangement direction of the first heat radiation fin group 17 and the second heat radiation fin group 48, Since the formation of a boundary layer is suppressed between the first heat radiating fin 11 and the second heat radiating fin group 42, it is possible to prevent the heat radiating efficiency of the heat radiating fins from being lowered. Furthermore, the flow of the cooling air is disturbed between the first heat radiation fins 11 and the second heat radiation fins 42, so that the heat transfer rate between the heat radiation fins and the cooling air can be improved.

Next, a heat sink according to an eighth embodiment of the present invention will be described with reference to the drawings. The same components as those of the heat sinks according to the first to seventh embodiments will be described using the same reference numerals.

As shown in FIG. 9, the heat sink 8 according to the eighth embodiment is not provided with heat pipes, and the first heat radiation fins 51 and the third heat radiation fins 53 serve as heat transfer members such as heat pipes. It is directly thermally connected to the base plate 10 without an intermediary.

The first radiation fin 51 is composed of a flat fin portion 51a and leg portions 51b and 51c erected at both ends of the flat fin portion 51a. A first radiation fin group 57 is formed by stacking a plurality of first radiation fins 51 . The first heat radiation fin group 57 is arranged so that cooling air flows between the leg portions 51b and 51c. The legs 51 b and 51 c of the first heat radiation fin 51 allow the cooling air flowing through the first heat radiation fin group 57 to flow out of the first heat radiation fin group 57 from the lateral side surfaces of the first heat radiation fin group 57 . It also functions as a shielding wall that blocks out the Therefore, the first heat radiation fin group 57 can more reliably supply the cooling air to the second heat radiation fin group 18 .

The flat plate-like fin portions 51a are arranged substantially vertically with respect to the surface of the base plate 10 at substantially equal intervals (that is, the intervals corresponding to the length of the leg portions 51b and 51c). Furthermore, all flat plate-like fin portions 51a are arranged such that their surfaces are substantially parallel to the surface of the base plate 10. As shown in FIG. In the heat sink 8 , the legs 51 b and 51 c of the first heat radiation fins 51 are thermally connected to the base plate 10 .

The third radiating fin 53 is composed of a flat plate-like fin portion 53a and leg portions 53b and 53c erected at both ends of the flat plate-like fin portion 53a. A third heat dissipating fin group 59 is formed by stacking a plurality of third heat dissipating fins 53 . The third heat dissipating fin group 59 is arranged so that cooling air flows between the leg portions 53b and 53c. The legs 53b and 53c of the third heat dissipating fin 53 allow the cooling air flowing through the third heat dissipating fin group 59 to flow out of the third heat dissipating fin group 59 from the lateral side surfaces of the third heat dissipating fin group 59. It also functions as a shielding wall that blocks out the Therefore, the third heat radiation fin group 59 can more reliably supply cooling air to the downstream side of the heat sink 8 .

The flat plate-like fin portions 53a are arranged substantially vertically with respect to the surface of the base plate 10 at substantially equal intervals (that is, the intervals corresponding to the length of the leg portions 53b and 53c). Further, all flat plate-like fin portions 53a are arranged such that their surfaces are substantially parallel to the surface of the base plate 10. As shown in FIG. In the heat sink 8 , the legs 53 b and 53 c of the third heat radiation fins 53 are thermally connected to the base plate 10 .

Next, an example of how to use the heat sink of the present invention will be described. Here, an example of usage will be described using the heat sink 1 according to the first embodiment. When cooling air is supplied to the heat sink 1 from the first heat radiation fin group 17 side, the heat sink 1 is installed so that the direction of circulation of the cooling air is substantially parallel to the surface of the first heat radiation fins 11 . Also, the portion of the base plate 10 to which the heating element (not shown) is thermally connected is not particularly limited. A position corresponding to the portion where the bottom portion 14c of the letter-shaped heat pipe 14 is attached can be mentioned.

Next, another embodiment of the heat sink of the present invention will be described. In the sixth and seventh embodiments, no shielding member is provided, but if necessary, a shielding member may be provided on the second radiation fin group. As the shielding member, for example, a U-shaped member in a front view consisting of three plane portions can be mentioned. The height from the base plate surface of the radiating fin group No. 3 can be mentioned as being substantially the same height.

In the above embodiments, the second heat radiation fins, which are lower than the height of the first heat radiation fin group from the base plate surface, have substantially the same height. Different heights may be used as long as they are lower than the height of the group from the base plate surface.

Further, in each of the above-described embodiments, the surfaces of the second heat radiation fins are provided in a direction substantially perpendicular to the surfaces of the first heat radiation fins. , and may not be parallel to each other, for example, the surface of the second heat radiating fin is at an angle other than vertical with respect to the base plate surface, that is, at an angle of more than 0° to less than 90° (for example, 70° to less than 90°). ), and the surface of the first heat radiating fin and/or the surface of the third heat radiating fin are parallel to the surface of the base plate in the arrangement direction of the second heat radiating fin. , that is, an angle of more than 0° to less than 90° with respect to the base plate surface (for example, an angle of more than 0° to 30° with respect to the base plate surface) in the arrangement direction of the second heat radiating fins You may

In addition, in the heat sinks according to the first to fifth and seventh embodiments, the straight portions of the heat pipes having the same shape and the same size are arranged in parallel on the base plate. Alternatively, three or more heat pipes may be provided, and the linear portions of the heat pipes may be arranged in a zigzag arrangement in order to facilitate the flow of cooling air in the heat sink.

In the above first to seventh embodiments, heat pipes were used, but instead of the heat pipes or together with the heat pipes, a metal (for example, aluminum , copper, etc.) may be used. In each of the above-described embodiments, the fin pitches of each heat radiation fin group are equal intervals, but the arrangement of the heat radiation fins of the heat radiation fin group may not be equal, and may be arranged at equal intervals. It is also possible to arrange the heat radiation fins in such a manner that some of the plurality of heat radiation fins are thinned out. A larger amount of cooling air can be supplied to the leeward side by thinning out some of the radiation fins.

In addition, in each of the embodiments described above, the shape of the second heat radiation fins is flat, but may be L-shaped or U-shaped for bonding to the base plate, if necessary.

INDUSTRIAL APPLICABILITY The heat sink of the present invention suppresses the formation of a boundary layer on the surface of the heat radiating fins and has excellent heat radiation performance even in areas other than the windward side of the cooling air, so it can be used in a wide range of fields. It has high utility value in the field of cooling electronic parts mounted on moving bodies such as aircraft and automobiles and electronic equipment.

1, 2, 3, 4, 5, 6, 7, 8 heat sink 10 base plate 11, 51 first radiation fin 12, 42 second radiation fin 13, 33, 53 third radiation fin 14, 24, 44 heat Pipes 17, 57 First radiation fin group 18, 48 Second radiation fin group 19, 39, 59 Third radiation fin group 60 Shielding member

Claims (5)

a base plate, at least one first heat dissipating fin thermally connected with the base plate, and at least one second heat dissipating fin adjacent to a side edge of the first heat dissipating fin and thermally connected with the base plate radiating fins, and
the surface of the first heat radiation fin is not parallel to the surface of the second heat radiation fin,
At least one of the second heat radiation fins is provided at a position lower than at least one of the first heat radiation fins in a direction perpendicular to the surface of the base plate,
A first heat dissipating fin group is formed from a plurality of the first heat dissipating fins, and the height of the second heat dissipating fins from the base plate surface relative to the height of the first heat dissipating fins from the base plate surface is 0.35 to 0.60 ,
the first heat radiation fins are thermally connected to the base plate only through a thermally conductive member that is thermally connected to the base plate;
the thermally conductive member is a heat pipe,
A heat pipe is not attached to the second heat dissipating fins, and the second heat dissipating fins are thermally connected by being in contact with the base plate at their lower ends,
at least one third heat radiation fin adjacent to the side end of the second heat radiation fin and thermally connected to the base plate, which is positioned on the leeward side of the cooling air relative to the second heat radiation fin; Further comprising, the surface of the third heat radiating fin is not parallel to the surface of the second heat radiating fin,
A heat sink provided with a shielding member for shielding the free end from the external environment on the side of the free end facing the lower end of the second heat radiation fin. A plurality of the second heat radiation fins are arranged along the surface of the base plate to form a second heat radiation fin group, and the second heat radiation fin is arranged at least in the center of the second heat radiation fin group. is located lower than at least one of said first heat radiating fins. 3. The heat sink according to claim 1 , wherein at least one of said second heat dissipating fins is provided at a position lower than at least one of said third heat dissipating fins in a direction perpendicular to said base plate surface. 4. The heat sink according to any one of claims 1 to 3, wherein said third heat radiation fins are thermally connected to said base plate via a heat conducting member. The heat sink according to any one of claims 1 to 4, wherein the shape of the heat pipe is U-shaped when viewed from the side, L-shaped when viewed from the side, or U-shaped when viewed from the side.

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