JPH08111480A - Cooling fin and its forming method - Google Patents

Abstract

PURPOSE: To cope with the increase of an board parts and required quantity of heat radiation by forming a frame part on which a to-be-cooled material such as a semiconductor device is in-stalled and a cooling rib part of a thin metal board, individually, and making them into an integral construction by caulking. CONSTITUTION: A frame 1 an which a semiconductor, etc., is installed and a cooling rib 2 which acts as a heat radiation part for radiating conducted heat from the frame 1 are formed of an aluminum thin board. A projected bass whose cross section is a circle and a circular hole for allowing the projected bass to pass through are formed an the frame 1 and the cooling rib 2, respectively, with press working. The frame 1 and the cooling rib 2 are, after the projected bass 3 is engaged with the circular hole 4, caulked with the use of a pair of dies whose upper die is projected shape, and the lower die recessed shape, so that, a cooling fin of an integral construction is formed. Thus, the increase of on board parts and required quantity of heat radiation are easily coped with.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling fin for mounting a semiconductor element or the like or a module forming an integrated body thereof for heat radiation cooling and a method for forming the cooling fin.

[0002]

2. Description of the Related Art As a conventional cooling fin of this type, there is known an aluminum material formed into a desired shape by an extrusion method or a die casting method.

[0003]

However, cooling fins manufactured by the conventional extrusion method or die casting method can be manufactured due to problems such as mechanical strength of the mold or warpage distortion due to heat shrinkage. Regarding the size of the fins, or regarding the complexity of the fin structure mainly including the cooling rib portion for increasing the heat radiation area, there is a restriction on the tong ratio that forms the ratio of the height of the cooling rib to the pitch, and The cooling fins have been rapidly increased in price in response to the increase in size and the increase in complexity required due to an increase in the required heat radiation amount.

In view of the above, an object of the present invention is to provide a lightweight and inexpensive cooling fin which can easily cope with an increase in the number of mounted parts or an increase in the required heat radiation amount.

[0005]

To achieve the above object, in the cooling fin and the method for forming the same according to the present invention, 1) according to claim 1, a semiconductor element or the like or a module forming an integrated body thereof is attached. In a cooling fin for cooling by radiative cooling, a frame portion to which a body to be cooled such as the semiconductor element and a cooling rib portion are separately formed by thin metal plates, and both are joined by caulking to form an integral structure. To do.

2) According to a second aspect, in the cooling fin according to the first aspect, the metal plates forming the frame portion and the cooling rib portion are aluminum thin plates. 3) According to claim 3, in the cooling fin according to claim 1, the shape of each cooling rib forming the cooling rib portion is a wavy shape formed by a combination of linear portions or arc portions.

4) According to a fourth aspect, in the cooling fin according to the first aspect, the cooling rib forming the cooling rib portion is provided with a plurality of heat radiating portions that are bent and projected on a metal plate, and the heat radiating portions are concentric with each other. It is made up of a plurality of metal plates that are stacked in a shape that fits each other. 5) According to claim 5, in the cooling fin according to claim 1, the frame part is extended so as to circulate around the cooling rib part, and at this extension part, a mounting part of the cooling fin at a predetermined position in a switchboard is formed. Shall be allowed.

6) According to a sixth aspect of the present invention, in the method for forming a cooling fin according to the first aspect, a convex boss is formed on the frame portion by pressing, and a convex boss is formed on the frame portion on each cooling rib. Through holes, and after fitting the frame-shaped convex bosses into the corresponding cooling rib holes, the frame is formed by using a pair of molds in which the upper mold is convex and the lower mold is concave. The part and each cooling rib are caulked and joined.

[0009]

According to the present invention, as described in claim 1, the cooling fin is provided with a frame portion which forms a mounting portion for a heat-generating component such as a semiconductor element and forms a good heat conducting portion, and a heat radiation portion for conducting heat from the frame portion. The cooling rib portion is formed separately from a thin metal plate such as an aluminum thin plate according to claim 2, and further, according to claim 6, a convex boss is formed on the frame portion by pressing and the cooling rib portion structure is formed. Each cooling rib is provided with a through hole of a convex boss formed in the frame portion, and after fitting each convex boss of the frame portion into the corresponding cooling rib hole, the upper die is convex. The cooling fin is formed by caulking and joining the frame portion and the cooling ribs using a pair of metal molds in which the lower mold is concave.

According to a third aspect of the present invention, the shape of each cooling rib is formed in a corrugated shape such as a triangular shape or a semicircular shape formed by an appropriate combination of straight line portions or circular arc portions, and the shape is within an allowable space in the arrangement. In order to expand the effective heat radiation surface area. Further, according to claim 4, the cooling rib forming the cooling rib portion is provided with a plurality of heat dissipating portions which are bent and protruded on a metal plate, and the heat dissipating portions are stacked in a concentric manner so as to be stacked on each other. When it is formed of a plate, it is possible to cope with an increase in heat radiation without changing the cooling rib pitch formed on the frame.

Further, according to a fifth aspect of the present invention, the frame portion is extended so as to go around the cooling rib portion, and the extension portion forms a mounting portion of the cooling fin at a predetermined position in the switchboard.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. In each of the following figures, components having the same function are designated by the same reference numeral. First, FIG. 1 and FIG.
2 is a sectional view of a basic portion of a cooling fin showing a first embodiment of a method for forming a cooling fin according to the present invention.

In FIG. 1, reference numeral 1 is a frame for mounting a semiconductor element or the like or a module or the like forming an integrated body thereof, 2
Is a cooling rib that forms a heat radiation portion for the conduction heat from the frame 1, both of which are formed of an aluminum thin plate. Also, 3
Is a convex boss having a circular cross section formed by pressing the frame 1, and 4 is a round hole provided in the cooling rib 2 for penetrating the convex boss.

Here, both the frame 1 and the cooling rib 2 are
As shown in FIG. 2, after the convex boss 3 is fitted into the round hole 4, the upper mold is crimped using a pair of molds having a convex lower mold and the lower mold is concave. Form the cooling fins. Next, FIG. 3 is an outline view showing the basic form of the cooling fin formed as described above, and shows a second embodiment of the present invention. As shown in the drawing, a U-shaped cooling rib 2 and a plurality of L-shaped cooling ribs 2a are joined to the frame 1 by caulking as described above to form a cooling fin.

Further, FIGS. 4 to 7 are outline views of cooling fins showing the third to sixth embodiments of the present invention, respectively, and regarding the shape of the cooling ribs, respectively, in the allowable space in the arrangement. This is to expand the effective heat radiation surface area. FIG. 4 shows a state in which both ends of the cooling rib are bent 90 degrees in opposite directions to form a cooling rib 2b, and the heat radiation surface area is enlarged.

In FIG. 5, a triangular bent portion is provided in the intermediate portion of the cooling rib 2b to form the cooling rib 2c, and the heat radiation surface area is enlarged. Further, in FIG. 6, a semicircular curved portion is provided in place of the triangular bent portion provided in the middle portion of the cooling rib 2c, and this is used as the cooling rib 2d to expand the heat radiation surface area. is there.

Further, in FIG. 7, a rectangular bent portion is provided in place of the triangular bent portion provided in the middle portion of the cooling rib 2c, and this is used as a cooling rib 2e to increase the heat radiation surface area. It is a thing. Further, FIG. 8 is an outline view of a cooling fin showing a seventh embodiment of the present invention. As shown in the drawing, a module mounting hole 5 is provided in the frame 1 and the cooling ribs 2 and 2a are circulated around the frame. Both ends of the cooling fin are extended, and mounting holes 6 are provided in the extended portions at predetermined positions in the switchboard, and the cooling fin is formed into a box shape by using the frame, and the cooling fin is stored. This is a convenient way to install the switchboard.

Further, FIG. 9 is an external view of a cooling fin showing an eighth embodiment of the present invention. In the drawing, 7 is a cooling rib, and a plurality of heat radiating portions 7 bent and projected in a rectangular shape.
It is composed of three metal plates having a, 7b, and 7c, and is formed by the heat dissipation portion 7a having a protruding height 7d and a width 7e and the heat dissipation portions 7b and 7c having different protruding heights and widths. The three metal plates are stacked so that the heat radiating portions 7a, 7b and 7c are concentrically fitted to each other, and the round holes 4 provided between the heat radiating portions are inserted into the boss 3 of the frame 1 to be integrated. It is attached to the frame 1 in a crimped form.

In this structure, the amount of heat can be increased by stacking the cooling ribs 7 without changing the cooling rib pitch.

[0020]

According to the present invention, there is provided a cooling fin for mounting a semiconductor element or a module or the like, which is an integrated body thereof, for heat radiation and cooling, and relates to a frame portion for mounting a cooled body and a cooling rib. And the cooling ribs that form the cooling ribs are caulked to form an integral structure. As a result, no special processing equipment according to the conventional extrusion method or die casting method is required, and the required equipment cost can be reduced.

Further, it becomes easy to increase the physical size of the frame portion and the cooling rib portion in conjunction with each other to cope with an increase in the number of mounted parts or an increase in the required heat radiation amount. Also, as long as the shapes are such that they can be crimped together, Even if the cooling fins that are integrated with each other have a complicated shape, they can be mass-produced at low cost. Also, it is not necessary to prepare a special mold for trial manufacture, and it is possible to carry out low-cost and early trial manufacture. .

Further, according to the present invention, according to the present invention, the restriction of the tong ratio forming the ratio of the height to the pitch of the cooling rib as described above is alleviated, and the cooling is greater than the conventional cooling rib. The area can be secured. Further, according to the fourth aspect, the cooling rib is formed of a plurality of metal plates by providing a plurality of heat radiating portions that are bent and protruded on the metal plate, and stacking the heat radiating portions in a concentric fit. It is possible to easily deal with an increase in the amount of heat only by stacking the cooling ribs without changing the cooling rib pitch.

Further, according to the fifth aspect, by forming the frame portion itself as a part of the box body to form the mounting portion to the switchboard, it is possible to reduce the size and weight of the entire cooling fin for the same cooling capacity. As described above, according to the present invention, it is possible to easily cope with an increase in the number of mounted parts or an increase in the required heat radiation amount, the relative cooling capacity can be increased, and a lightweight and inexpensive cooling fin can be obtained. You can

[Brief description of drawings]

FIG. 1 is a sectional view of a basic portion of a cooling fin showing a first embodiment of the present invention.

FIG. 2 is a sectional view of a basic portion of a cooling fin corresponding to FIG.

FIG. 3 is an external view of a cooling fin showing a second embodiment of the present invention.

FIG. 4 is an external view of a cooling fin showing a third embodiment of the present invention.

FIG. 5 is an external view of a cooling fin showing a fourth embodiment of the present invention.

FIG. 6 is an external view of a cooling fin showing a fifth embodiment of the present invention.

FIG. 7 is an external view of a cooling fin showing a sixth embodiment of the present invention.

FIG. 8 is an external view of a cooling fin showing a seventh embodiment of the present invention.

FIG. 9 is an external view of a cooling fin showing an eighth embodiment of the present invention.

[Explanation of symbols]

 1 Frame 2 Cooling Ribs 2a to 2e Cooling Ribs 3 Boss 4 Round Hole 5 Module Mounting Hole 6 Cooling Fin Mounting Hole 7 Cooling Ribs 7a to 7c Heat Dissipator

Claims (6)

[Claims] 1. A cooling fin for mounting a semiconductor element or the like or a module forming an integrated body thereof for radiative cooling, wherein a frame portion and a cooling rib portion to which a cooled body such as the semiconductor element is mounted are thin. A cooling fin, which is formed separately from the metal plate and is joined by caulking to form an integral structure. 2. The cooling fin according to claim 1, wherein each of the metal plates forming the frame portion and the cooling rib portion is a thin aluminum plate. 3. The cooling fin according to claim 1, wherein each of the cooling ribs forming the cooling rib portion has a wavy shape formed by a combination of straight line portions or arc portions. 4. The cooling fin according to claim 1, wherein the cooling rib forming the cooling rib portion is provided with a plurality of heat radiating portions that are bent and protruded on a metal plate, and the heat radiating portions are concentrically fitted to each other. A cooling fin, which is made up of a plurality of metal plates stacked on top of each other. 5. The cooling fin according to claim 1, wherein the frame portion is extended so as to surround a cooling rib portion, and the extension portion forms a mounting portion of the cooling fin at a predetermined position in a switchboard. A cooling fin. 6. The method for forming a cooling fin according to claim 1, wherein a convex boss is formed on the frame portion by pressing, and the convex rib formed on the frame portion is formed on each of the cooling ribs. A hole is formed through the boss, and after the convex boss of the frame is fitted into the corresponding cooling rib hole, a pair of dies having an upper die convex and a lower die concave is used. A method for forming a cooling fin, characterized in that the frame portion and the cooling ribs are caulked and joined.