JPH11163235A - Heat sink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a heat sink which is compact in structure, high in cooling performance, and superior in high volume production. SOLUTION: A fan 1 provided to the side of a box-shaped body 2, and a large number of plate fins 4 are laminated inside the body 2. A through-hole 3 is provided to the plate fins 4 respectively, where the through-holes 3 each provided to the plate fins 4 are aligned with each other, an a slight cylindrical burring 4a is formed of the peripheral edges of the through-hole 3. Small pieces 4b used as spacers are formed through cutting and lifting the plane fin 4 at the same height as that of the bar rings 4a, and a columnar body 6 is fitted in the through-hole 3, and a semiconductor mounting plane 5 is provided to the upside of the columnar body 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat sink for cooling a semiconductor device, which is compact and has a blower.

[0002]

2. Description of the Related Art A conventional heat sink has a base portion and a number of fin portions arranged at regular intervals perpendicular to the base portion. The base portion and the fin portion include one manufactured integrally by extrusion of aluminum and one formed by joining both by brazing. Then, the semiconductor element is brought into contact with the base portion, and the two are fastened and fixed with bolts or the like.

[0003]

In a conventional heat sink in which the edge of the fin material is brazed to the base member, the edge of the thin fin material and the surface of the base member are orthogonal to each other. Since the contact portion is brazed, there is a disadvantage that the brazing strength is weak. Further, in the extruded product, the distance between the fins could not be reduced. Therefore, there was a drawback that the cooling performance could not be improved. Accordingly, the present invention is to solve these problems and to provide a heat sink that is compact and easy to assemble.

[0004]

A heat sink according to the present invention has a box-shaped main body 2 having a pair of opposing side surfaces opened, and a cooling blower 1 connected to one of the side surfaces. Parallel to its bottom and slightly apart from each other,
A large number of plate fins 4 having a plurality of plate fins 4 provided therein and having through holes 3 aligned with each other, and
A burring portion 4a formed in a slightly cylindrical shape at the edge of the hole;
At the same height as the burring portion 4a, there are a plurality of small pieces 4b for a spacer cut and raised from the plane of the plate fin, and an outer periphery aligned with the through hole 3, and each of the through holes has a peripheral surface. The semiconductor mounting surface 5
And a columnar body 6 provided with.

According to this heat sink, the columnar body 6 serving as a base material and the respective plate fins 4 are densely stacked at the height of the burring portion 4a and the small piece portion 4b, so that the heat sink has a large heat capacity and a large cooling performance. Can be provided. In addition, a heat sink that is easy to assemble and has a large capacity can be provided. Further, a burring portion 4a and a small piece portion 4b are formed on the plate fin 4, and the heights of the burring portion 4a and the small piece portion 4b are the same. Therefore, when the columnar body 6 is inserted into the burring portion 4a, each of the portions of the adjacent plate fin 4 becomes The cooling effect of the semiconductor element can be improved as a whole by keeping the intervals constant and parallel, making the cross sections of the air passages uniform. Moreover, since a large number of plate fins 4 are substantially stacked up to the height of the main body 2, it is possible to provide a compact heat sink having a high cooling effect with uniform ventilation resistance of each part in the cross section of the ventilation path, uniform ventilation.

Next, a second aspect of the present invention is a preferred embodiment of the first aspect of the present invention, wherein each of the plate fins 4 is formed to be identical to each other, and the small piece portion 4b has a tip end. Is formed to have a narrow inverted trapezoidal shape at the base with its width wide, its leading edge being in contact with an adjacent plate fin, and the rising surface of the small piece portion 4b being parallel to the blowing direction of the blowing device 1. It is a disposed heat sink. According to the present invention, the small piece portion 4 of the plate fin 4 is provided.
Since the front end surface of b is wider than the root, when the plate fins 4 of the same shape are stacked, the front end of the small piece portion 4b is bridged to the opening at the base of the small piece portion 4b of the adjacent plate, and is reliably adjacent. The distance between the plate fins 4 can be maintained. In addition, since the rising surface of the small piece portion 4b is arranged parallel to the blowing direction, the ventilation resistance is reduced, the cooling air flows smoothly, and the heat dissipation is improved.

The present invention according to claim 3 is a preferred embodiment of the invention according to claim 1, wherein a plurality of the through holes 3 are formed in each of the plate fins 4 and each of the through holes 3 is formed. A fixing plate 8 having a plurality of mounting holes 7 aligned with the main body 2 is fixedly attached to an upper end opening of the main body 2, and a flange portion 9 is projected from an outer periphery of an upper end of the columnar body 6. This is a heat sink to which the columnar body 6 is attached so as to contact the fixing plate 8. According to the present invention, each of the plate fins 4 has a plurality of columnar members 6.
Are fixed in contact, and a plurality of semiconductor elements can be cooled in a small space.

Next, a fourth aspect of the present invention is a preferred embodiment of the third aspect of the present invention,
The plate fins 4 are mounted on the
After the fixing plate 8 is fixed, the columnar body 6 is a heat sink that is pressed into the through hole 3. According to the present invention, after the semiconductor element 15 is mounted on the column 6 in advance, the column 6 can be mounted on the through hole 3 of the plate fin 4. Thereby, the attachment property of the semiconductor is good. Further, since a required number of columnar bodies 6 can be mounted, when a smaller number of columnar bodies 6 than the number of through holes 3 are mounted, a higher cooling effect is obtained. .

According to a fifth aspect of the present invention, there is provided a preferred embodiment of the first aspect of the present invention, wherein a large number of the plate fins 4 are fixedly contacted to the outer periphery of the columnar body 6 to constitute the element 10. A plurality of mounting holes 7 substantially aligned with the outer periphery of the element 10 are provided on the upper surface of the main body 2 at a distance from each other, and the heat sink is provided with the element 9 in each of the mounting holes 7. According to the present invention, by mounting the required number of elements,
The cooling effect can be enhanced by increasing the amount of air blow.

[0010]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic exploded sectional view of a main part of a heat sink according to the present invention. FIG. 2 is a cross-sectional view of a main part showing the assembled state, and FIG. 3 is a partial explanatory view of a plate fin 4 of the heat sink. This heat sink includes a main body 2 obtained by bending a metal plate such as aluminum into a groove shape, a fixing plate 8 for closing the upper end thereof, a large number of plate fins 4 laminated in the main body 2, And a columnar body 6 to be inserted into the through hole 3 of the plate fin 4. The body 2 has a box shape in which a pair of opposing side surfaces are opened, and the blower 1 is connected to the bottom surface. Then, separate slightly in parallel with the side,
The plate fins 4 are stacked substantially up to the height of the main body 2. The plate fins 4 are provided with through holes 3 having the same shape and aligned with each other, and a burring portion 4 a formed in a slightly cylindrical shape is provided at the edge of the through hole 3.

A plurality of small pieces 4b for the spacer cut and raised from the plane of the plate fin 4 at the same height as the burring portion 4a are arranged at symmetric positions with respect to the through hole 3 as shown in FIGS. Have been. This small piece portion 4b
The tip is wide and the base is formed in a narrow inverted trapezoidal shape. That is, as shown in FIG. 3, the small pieces whose both sides and the bottom are cut are bent at right angles to the plane of the plate fin 4. And the plate fin 4 whose leading edge is adjacent
The small piece portion 4b is formed so as to be in contact with the root of the small piece portion 4b, and the rising surface of the small piece portion 4b is arranged parallel to the blowing direction of the blower 1. The thickness of the small piece portion 4b is
And, it is formed extremely thin as compared with the fixing plate 8.

Next, the main body 2 has a claw portion 11 cut and raised on a flange at an upper edge thereof. A hole is formed in the fixing plate 8 attached to the upper end of the main body 2 at a position corresponding to the claw portion 11, and the claw portion 11 is inserted there and caulked to fix the fixing plate 8 on the upper surface of the main body 2. Is fixed. The fixing plate 8 is provided with a mounting hole 7 at a position corresponding to the through hole 3 of the plate fin 4. next,
The columnar body 6 has a height equal to the sum of the depth of the main body 2 and the thickness of the mounting hole 7, a flange portion 9 is integrally provided on the outer periphery of the upper end, and the semiconductor mounting surface 5 is formed on the upper surface thereof. The semiconductor element 15 is fixed to the semiconductor mounting surface 5 via bolts or the like. On the lower surface side of the columnar body 6, a convex portion 12 for caulking is slightly provided in a projecting manner. And the convex part for the caulking
A hole 16 is pre-drilled in the bottom surface of the main body 2 so as to match the position of the body 12.

In this example, as shown in FIG. 1, a large number of plate fins 4 are stacked in the main body 2, a fixing plate 8 is fixedly fixed to the upper end thereof, and the blower 1 is fixed to one side of the main body 2. You. Thereafter, the columnar body 6 is lightly pressed into the mounting hole 7 of the fixing plate 8 and the through hole 3 of the plate fin 4, and the outer peripheral surface of the columnar body 6 and the burring portion 4a of the plate fin 4 are pressed. After that, the outer peripheral surface of the columnar body 6 and the burring portion 4a of the through hole 3 can be fixed by brazing. These components are preferably made of a good heat conductive material such as aluminum. After the columnar body 6 is fitted into the mounting hole 7 and the through hole 3 and the caulking convex portion 12 is inserted into the hole 16, the edge of the caulking convex portion 12 is caulked outward as shown in FIG. Thereby, it can be fixed to the main body 2.

FIG. 4 is an exploded perspective view of a second heat sink according to the present invention. In the heat sink of this example, a plurality of mounting holes 7 are formed in the upper surface of the cylindrical main body 2 whose both sides in the longitudinal direction are open. The blower 1 is disposed on one side of the main body 2 in the longitudinal direction. Elements 10 are arranged in the mounting holes 7 of the main body 2 respectively. The element 10 has a large number of plate fins 4, a fixed plate 8 disposed at the uppermost position thereof, and a columnar body 6. As shown in FIG. 5, a through hole 3 is formed at the center of the plate fin 4, and a burring portion 4a is raised at the edge of the hole. At the same time, a small piece portion 4b is formed by being cut and raised at the periphery. These points are the same as in the example of FIG. Then, the columnar body 6 is pressed into the mounting holes and the through holes of the fixing plate 8 and the plate fins 4, and the semiconductor element 15 is fixed to the semiconductor mounting surface 5 of the columnar body 6 via bolts 14 or the like.
The edge of the fixing plate 8 is fastened to the edge of the mounting hole 7 of the main body 2 via another bolt 14. In addition,
Also in this example, a case where the columnar body 6 is used while being lightly pressed into the through hole 3 of the plate fin 4, and a case where the columnar body 6 and the burring portion 4 a of the plate fin 4 are then brazed and fixed. Exists.

[0015]

According to the heat sink of the first aspect of the present invention, when the height of the small piece portion 4b for the spacer coincides with that of the burring portion 4a and the columnar body 6 is inserted,
The intervals between the adjacent portions of the plate fins 4 are kept constant and parallel, and the cross sections of the air passages are made uniform, so that the cooling effect of the semiconductor element is improved as a whole. At the same time, a heat sink having a large capacity can be provided. In addition, since a large number of plate fins 4 are stacked substantially up to the height of the main body 2, the ventilation resistance of each section in the cross section of the ventilation path is made uniform, and the ventilation is uniformly guided without waste, and the cooling effect of the semiconductor element is improved. It becomes a high compact heat sink. In the heat sink according to the second aspect, since the tip end surfaces of the small piece portions 4b are wider than the roots, in the plate fins having shapes matching with each other, the tip ends of the small piece portions 4b are openings at the bases of the small piece portions 4b of the adjacent plate fins. Located on a narrow portion of the bridge, which can bridge and ensure that the adjacent plate fins 4 are supported. This is because the tip of the small piece portion 4b is formed to be longer than the base length, so that the tip can straddle the cut and raised opening. Furthermore, since the rising surface of the small piece portion 4b is arranged in parallel to the blowing direction, the ventilation resistance is reduced, the cooling air is smoothly circulated, and the heat dissipation is improved.

In the heat sink according to the third aspect, the plurality of columnar bodies 6 are fixedly contacted to the respective plate fins 4, so that the plurality of semiconductor elements can be cooled in a small space. According to the heat sink of the present invention, the columnar body 6 is press-fitted into the through-hole 3 of the plate fin after a large number of plate fins 4 are mounted on the main body 2 in advance. Later, the columnar body 6 can be mounted in the through hole of the plate fin. Thereby, assemblability is good.
Also, since a required number of columnar bodies 6 can be mounted, when a smaller number of columnar bodies 6 than the number of through holes 3 are mounted, the cooling effect is higher. The heat sink of claim 5 is
Since the element 10 is removably mounted in the mounting hole 7 of the main body 2, by mounting the required number of elements 10, the air flow rate can be increased and the cooling effect can be enhanced.

[Brief description of the drawings]

FIG. 1 is a schematic exploded sectional view of a main part of a heat sink according to the present invention.

FIG. 2 is a cross-sectional view of a main part showing an assembled state of the heat sink.

FIG. 3 is a partial explanatory view of a plate fin 4 of the heat sink.

FIG. 4 is an exploded perspective view of a second heat sink according to the present invention.

FIG. 5 is a cross-sectional view of a main part of the heat sink.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 blower 2 main body 3 through hole 4 plate fin 4 a burring portion 4 b small piece portion 5 semiconductor mounting surface 6 columnar body 7 mounting hole 8 fixing plate 9 flange portion 10 element 11 claw portion 12 convex portion for caulking 14 bolt 15 semiconductor element 16 hole

Claims (5)

[Claims] 1. A box-shaped main body 2 having a pair of opposing side surfaces opened and a cooling air blower 1 connected to one of the side surfaces, and the main body 2 being slightly attached to each other in parallel with its bottom surface. A large number of plate fins 4 which are spaced apart from each other and are substantially stacked to the height of the main body 2 and which have through holes 3 aligned with each other, and holes of the through holes 3 of the plate fins 4; A burring portion 4a formed in a slightly cylindrical shape at an edge; a plurality of small pieces 4b for a spacer cut and raised from the plane of the plate fin 4 at the same height as the burring portion 4a; And a columnar body 6 having a peripheral surface in contact with each of the through holes 3, the peripheral surface of which is fitted into contact with each of the through holes 3, and a semiconductor mounting surface 5 provided on the upper surface. 2. The method according to claim 1, wherein each of the plate fins is formed identically to each other.
The small piece portion 4b is formed in an inverted trapezoidal shape with a wide end and a narrow one at the root, and a tip edge thereof is formed so as to be in contact with an adjacent plate fin. A heat sink arranged in parallel to the air blowing direction of the device 1. 3. The main body according to claim 1, wherein a plurality of the through holes are formed in each of the plate fins, and a plurality of fixing holes having a plurality of mounting holes aligned with the respective through holes are provided in the main body. 2 and a flange 9 is projected from the outer periphery of the upper end of the columnar body 6, and the columnar body 6 is attached so that the flange 9 contacts the fixing plate 8. heatsink. 4. The pillar according to claim 3, wherein the plurality of plate fins are mounted on the main body, and the columnar body is pressed into the through hole after the fixing plate is fixed. heatsink. 5. The element according to claim 1, wherein a number of said plate fins are fixedly contacted to an outer periphery of said columnar body to form an element, and each of said mounting holes is substantially aligned with an outer periphery of said element.
A plurality of heat sinks are provided on the upper surface of the main body 2 apart from each other, and the elements 10 are mounted in the respective mounting holes 7.