JPH088562A - Method for fitting heat sink, and heat sink - Google Patents

Abstract

PURPOSE:To fit a heat sink to a printed board through a simple working process without inverting the printed board. CONSTITUTION:Notched grooves 20A and 20B are provided in both side face sections of a U-shaped heat sink 25A. The heat sink 25A is fitted to a printed board 15 by inserting the projections of the heat sink 25A into the holes 23A and 23B of the printed board 15 and bending deformed pieces 22A and 22B which are produced when the grooves 20A and 20B are formed around a straight line which is perpendicular to the board 15 and passes through the innermost parts of the grooves 20A and 20B so that the extensions 18A and 18B of the projections 13A and 13B can be shifted from the holes 23A and 23B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for mounting a heat dissipation component, for example, a heat sink for a power transistor, mounted on a printed circuit board, and a heat sink directly used for this method.

[0002]

2. Description of the Related Art Conventionally, as a method of attaching a heat sink to a printed circuit board, there is one shown in FIGS. When the heat sink 41A is attached to the printed circuit board 42, the printed circuit board 42 is attached to the edge 43 of the heat sink body 41B where the heat sink body 41B and the printed circuit board 42, which compose the heat sink 41A, come into contact with each other.
44A, 44B protruding with the same length as the thickness of the
And the projections 46A formed in an L shape by the fixed portions integrally formed at the tips of the protrusions 44A and 44B and the extension portions 45A and 45B extending from the tips along the plate surface of the printed circuit board 42. , 46B and a printed circuit board 42 having mounting holes 47A, 47B into which the protrusions 46A, 46B can be inserted, and the protrusions 46A, 46B are respectively inserted into the mounting holes 47A, 47B. By bending the extension portions 45A and 45B around the insertion direction (see FIG. 15) (see FIG. 16), the protrusions 46A and 46B are displaced from the positions of the attachment holes 47A and 47B, respectively, and the attachment holes 47 are attached.
The heat sink 41A is attached to the printed circuit board 42 without being separated from the A and 47B.

[0003]

By the way, in reality, many electronic components other than the heat sink 41A are inserted in the printed circuit board 42, and in this state, they are poured into a solder bath and soldered. However, the printed circuit board 42 into which a large number of electronic components have been inserted before being poured into the solder bath is in an unstable state because the electronic components are not fixed by solder. Therefore, the heat sink 41 is attached to the unstable printed circuit board 42 in which a large number of electronic components before being poured into the solder bath as described above are inserted.
When mounting A, the printed circuit board cannot be turned over, and the extension parts 45A and 45B must be bent from the surface opposite to the insertion surface of the printed circuit board 42, that is, the lower back surface, There was a problem that this work was very difficult. By the way, if the printed circuit board 42 before being poured into the solder bath is turned over, the inserted electronic parts will come off. There is also a method in which the heat sink is attached after the printed circuit board is poured into the solder bath, but this is troublesome because the power transistor attached to the heat sink must be manually re-soldered. SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems, and to provide a heat sink mounting method and a heat sink using this method, which can be mounted by a simpler working process without inverting the printed circuit board. .

[0004]

SUMMARY OF THE INVENTION The present invention for solving the above-mentioned problems is a method of attaching a heat sink to a printed circuit board, wherein the heat sink body and the printed circuit board are attached to the printed circuit board. A rigid heat sink configured by two or more protrusions protruding from an edge portion of the heat sink body in contact with the heat sink body, wherein at least one of the protrusions is printed on the edge portion of the heat sink body. A protrusion formed to have a length substantially the same as the thickness of the substrate, and an extension formed integrally with the protrusion in a direction along the plate surface of the printed substrate with the heat sink attached to the printed substrate. And a heat sink configured in an L shape,
A printed circuit board in which the projections are fitted, and holes are formed in the printed circuit board to prevent movement of the heat sink along the plate surface by the fitting, and the projections have the extension portions. A hole into which the extension is inserted, a protrusion of the protrusion having the extension and a portion along the insertion direction of the protrusion into the hole of the printed circuit board in the heat sink body. A printed circuit board having an arc-shaped portion having a radius approximately equal to the distance from the straight line between the center of the portion and the protrusion next to the protrusion to the protrusion having the extension portion is provided, and the straight line is the center, By bending the heat sink body, the extension portion is displaced from the hole through which the extension portion is inserted, so that the heat sink can be attached to the printed circuit board. A. Further, the heat sink is provided with a notch groove in a direction along the printed circuit board surface in the vicinity of the protrusion having the extension portion in the heat sink body, and the innermost part of the notch groove is a protrusion portion forming the protrusion. It is possible to reach a position slightly beyond the side edge on the side opposite to the extension direction of the extension part and form an extension groove extending from the innermost part toward the printed circuit board, or the extension part It may be omitted. Further, as the heat sink, a thin portion may be provided on the heat sink body along the straight line.

[0005]

By adopting such a method, the heat sink can be attached to the printed circuit board by the operation of bending the heat sink body only from the insertion surface without inverting the printed circuit board. Further, by providing the cutout groove, the extension groove, and the thin portion as in the heat sink, the heat sink body can be easily bent.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a U-shaped heat sink 1A and a printed circuit board 2, FIG. 2 is a side view, and FIGS. 3A and 3B are top views of the heat sink body 1B before and after bending, respectively. 4A and 4B
5A and 5B are views showing the positions of the holes 7A, 7B and the projections 4A, 4B before and after bending the heat sink body 1B, respectively, and FIG. 5 is a perspective view in a state where the heat sink 1A is attached to the printed board 2. Heat sink body 1B
And a heat sink 1A attached to the printed circuit board 2, and a rigid heat sink 1A constituted by projections 4A and 4B protruding from the edge 3 of the heat sink body 1B in contact with the printed circuit board 2. The protrusion 4
A and 4B are the protrusions 5A and 5B protruding from the edge 3 of the heat sink body 1B and having a length substantially the same as the thickness of the printed circuit board 2, and the heat sink 1A is attached to the printed circuit board 2. In this state, the heat sink 1A having an L-shape is formed in the direction along the plate surface of the printed circuit board 2 by the extension portions 6A and 6B integrally formed with the protrusions 5A and 5B. The projections 4A and 4B are fitted into the printed circuit board 2 and holes 7A and 7B are formed in the printed circuit board 2 to prevent movement of the heat sink along the plate surface of the printed circuit board 2 by the fitting. The holes 7A and 7B into which the projections 4A and 4B having the extension portions 6A and 6B are fitted are respectively inserted portions 8A and 8B into which the extension portions 6A and 6B are inserted.
And the protrusions 5A, 5B of the protrusions 4A, 4B along the insertion direction of the protrusions 4A, 4B into the holes 7A, 7B of the printed circuit board 2 in the heat sink body 1B and having the extension portions 6A, 6B. From the straight lines 11A, 11B (11B not shown) between the center of the projection and the projections 4A, 4B next to these projections 4A, 4B to the projections 4A, 4B having the extensions 6A, 6B. A printed circuit board 2 including arc-shaped portions 9A and 9B having a radius substantially equal to the distance is prepared. And the holes 7A, 7B
By bending the heat sink body 1B about the straight lines 11A and 11B with the extension portions 6A and 6B inserted through the insertion portions 8A and 8B, the extension portions 6A and 6B are inserted into the extension portions 6A and 6B. The heat sink 1A is attached to the printed circuit board 2 by being displaced from the inserted portions 8A and 8B. Incidentally, 1C is a power transistor attached to the heat sink 1A as is well known.

FIG. 6 is for explaining the second embodiment. The U-shaped heat sink 1D having substantially the same structure as the heat sink 1A shown in FIGS. 1 to 5 has the straight lines 11A and 11B. Along the side 10 of this heat sink
A, 10B (10B is not shown) and thin portions 12A, 12
B (12B is not shown) is provided to facilitate bending when bending. Therefore, by providing the thin portions 12A and 12B on the heat sink 1A, the attachment to the printed circuit board 2 becomes easier. Note that, in FIG. 6, the same reference numerals as those in FIGS. 1 to 5 denote the same components.

7 to 10 show a third embodiment of the present invention, and FIG. 7 is a perspective view of a heat sink 25A,
8 is a side view showing a state where the heat sink 25A is inserted in the printed circuit board, FIG. 9 is a plan view showing a state where the heat sink 25A is attached to the printed circuit board 15, and FIG. 10 is a state where the heat sink 25A is attached to the printed circuit board 15. It is a perspective view. 13A and 13B are U-shaped heat sinks 25
Projections 17A and 17B, which are projections formed on the side surfaces 14A and 14B of A, are provided on the edge portion 16 that comes into contact with the printed circuit board 15 when the printed circuit board 15 is mounted on the printed circuit board 15, which will be described later. The projections 17A and 17B are integrally fixed to the tips of the printed board 1 from the tips.
It is formed in an L-shape by the extension portions 18A and 18B extended along the plate surface of No. 5. Reference numerals 20A and 20B denote edge portions 19A and 19B which are near the protrusions 13A and 13B on the side surfaces 14A and 14B of the heat sink 25A and which intersect the edge portion 16 of the heat sink 25A.
Is a notch groove provided at a predetermined distance from the edge portion 16 and in parallel with the plate surface of the printed circuit board 15 in a state of being attached to the printed circuit board 15. The innermost portions of the cutout grooves 20A, 20B are the protrusions 13A, 13B.
The extension 1 in the protrusions 17A and 17B that form the
Side edges 24A, 24 opposite to the extension direction of 8A, 18B
An extension groove 21 extending to a position slightly beyond B or extending from the innermost portion toward the printed circuit board 15
A and 21B are formed respectively. The cutout grooves 20A and 20B and the extension grooves 21A and 21B form deformation pieces 22A and 22B, respectively. Also,
The printed board 15 is provided with mounting holes 23A and 23B slightly larger than the bottom surfaces of the protrusions 13A and 13B so that the protrusions 13A and 13B can be inserted in advance.
The operation of the above embodiment will be described. First, the mounting holes 23A, 2 which are previously opened in the printed circuit board 15.
3B, the protrusions 13A and 13B are respectively inserted, and then the deformation pieces 22A and 22B are attached to the protrusions 17A and
Bend about the line along the above-mentioned side edges 24A and 24B of 17B. As a result, the heat sink 12 can be attached to the printed board 15. By the way, in FIG. 10, the deformable pieces 22A and 22B are bent toward the outside of the heat sink 25, but it is preferable to bend the deformed pieces 22A and 22B toward the inside because the space of the substrate is small. Here, even when the extension grooves 21A and 21B are not provided, the deformation pieces 22A and
It is possible to bend 22B as described above. Figure 10
In the figure, reference numeral 25C is a power transistor, which is attached to the heat sink 25C as is well known.
11 to 12 are for explaining the fourth embodiment, in which a protrusion 35A, 35B is provided on a heat sink 34A substantially similar to the U-shaped heat sink 1A of FIG.
The printed circuit board in the state of being attached to the printed circuit board 29 at a predetermined distance from the edge portion 36 at the edge portions 37A and 37B near the protrusions 35A and 35B and intersecting the edge portion 36 of the heat sink 34A. Notch grooves 38A and 38B are provided in parallel with the plate surface of 29. The innermost portions of these cutout grooves 38A and 38B are the same as the projection 35
The protrusions 39A and 39B forming the protrusions A and 35B reach substantially the same positions as the side edges 26A and 26B in the extension direction of the extension portions 40A and 40B that intersect the extension line perpendicular to the printed board 29. Further, the side edge 27 on the side opposite to the extension direction of the extension portions 40A, 40B of the protrusions 35A, 35B.
Notch grooves 28A and 28B are also provided in a direction perpendicular to the printed circuit board 29 from A and 27B. The cutout grooves 28A and 28B extend to the extension lines of the cutout grooves 38A and 38B. The deformation piece 31 is formed by these two kinds of notch grooves.
A and 31B are formed. The operation of the above-described embodiment will be described. First, the protrusions 35A and 30B are respectively formed in the holes 30A and 30B previously formed in the printed circuit board 29.
35B is inserted, and then the deformation pieces 31A, 31B are formed by providing the cutout grooves 28A, 28B, 38A, 38B, and the base portion 3 of the deformation pieces 31A, 31B.
Bent at the center lines perpendicular to the plate surface of the printed circuit board 29 in 2A and 32B. As a result, the protrusion 35
The heat sink 34A is attached to the printed circuit board 29 with the A and 35B displaced from the holes 30A and 30B. The reference numerals 26B, 27B, 28B, 30B, 31B, 32
B, 35B, 37B, 38B, 39B, 40B are not shown. By the way, in the first embodiment, when the distance is set to zero or approaches zero, the arcuate portions 9A and 9B are substantially eliminated, and the mounting holes 7A and 7B are Only the insertion holes 8A and 8B are provided. That is,
The mounting hole of the printed circuit board is as in the third or fourth embodiment. Further, in each of the above embodiments, the case where the number of protrusions is two has been described, but a larger number of protrusions may be provided.
Further, the extension does not necessarily have to be provided on all of these protrusions.

[0009]

As described above, according to the present invention, by bending the heat sink body, the extension portion of the heat sink is displaced from the mounting hole, whereby the protrusion of the heat sink is prevented from coming off the mounting hole of the printed circuit board, and the heat sink is mounted on the printed circuit board. To be Therefore, it is possible to mount the heat sink on the printed circuit board without turning over the printed circuit board with a large number of electronic components inserted. Also, since the printed circuit board can be flowed into the solder bath with the heat sink attached to the printed circuit board, it is not necessary to attach the heat sink afterwards and solder the power transistor etc. to be attached to the heat sink. Can be done.

[Brief description of drawings]

FIG. 1 is a perspective view for explaining a first embodiment of the present invention.

FIG. 2 is a side view for explaining the first embodiment of the present invention.

FIG. 3 is a plan view of an essential part for explaining the first embodiment of the present invention.

FIG. 4 is a bottom view of an essential part for explaining the first embodiment of the present invention.

FIG. 5 is a perspective view of a main part for explaining the first embodiment of the present invention.

FIG. 6 is a side view for explaining the second embodiment of the present invention.

FIG. 7 is a perspective view for explaining a third embodiment of the present invention.

FIG. 8 is a side view of an essential part for explaining a third embodiment of the present invention.

FIG. 9 is a plan view of an essential part for explaining a third embodiment of the present invention.

FIG. 10 is a perspective view of a main part for explaining a third embodiment of the present invention.

FIG. 11 is a side view for explaining the fourth embodiment of the present invention.

FIG. 12 is a bottom view for explaining the fourth embodiment of the present invention.

FIG. 13 is a perspective view for explaining a conventional example.

FIG. 14 is a side view for explaining a conventional example.

FIG. 15 is a bottom view for explaining a conventional example.

[Explanation of symbols]

 1A heat sink 1B heat sink body 1C power transistor 1D heat sink 2 printed circuit board 3 edge of heat sink 4A, 4B protrusion 5A, 5B protrusion 6A, 6B extension of protrusion 7A, 7B mounting hole 8A, 8B insertion portion 9A, 9B arc-shaped portion 10A, 10B Side surface of heat sink 11A, 11B Straight line 12A, 12B Thin portion 13A, 13B Projection 14A, 14B Side surface of heat sink 15 Printed board 16 Edge of heat sink 17A, 17B Projection portion 18A, 18B Projection 19A, 19B Edge of heat sink 20A , 20B Notched groove 21A, 21B Extended groove 22A, 22B Deformation piece 23A, 23B Mounting hole 24A, 24B Side edge 25A Heat sink 25B Heat sink body 25C Power transistor 26A, 26B, 27 , 27B Side edge 28A, 28B Cutout groove 29 Printed circuit board 30A, 30B Mounting hole 31A, 31B Deformation piece 32A, 32B Root 34A Heat sink 35A, 35B Projection 36 Edge 37A, 37B Edge 38A, 38B Cutout groove 39A, 39B Protrusions 40A, 40B Extensions 41A Heatsink 41B Heatsink body 42 Printed circuit board 43 Edges 44A, 44B Protrusions 45A, 45B Extensions 46A, 46B Protrusions 47A, 47B Mounting holes

Claims (4)

[Claims] 1. A method of attaching a heat sink to a printed circuit board, comprising: a heat sink main body; and two or more protrusions protruding from an edge of the heat sink main body that are in contact with the printed circuit board when the heat sink is attached to the printed circuit board. A rigid heat sink configured by, wherein at least one of the protrusions is a protrusion that is provided at the edge of the heat sink body and has a length substantially the same as the thickness of the printed circuit board. A heat sink formed in an L shape by an extension portion integrally formed with the protrusion in a direction along the plate surface of the printed circuit board with the heat sink attached to the printed circuit board, and the protrusion. Are fitted together, and this fitting prevents movement of the heat sink along the plate surface with respect to the printed circuit board. A printed circuit board having a hole formed therein, wherein a hole into which a protrusion having the extension is fitted is formed in a portion through which the extension is inserted and in the hole of the printed circuit board in the heat sink body. A circle along the insertion direction of the protrusion and having a radius substantially equal to the distance from the straight line between the center of the protrusion of the protrusion having the extension and the protrusion next to the protrusion to the protrusion having the extension. A printed circuit board having an arc-shaped portion is prepared, and by bending the heat sink body about the straight line, the extension portion is displaced from the hole through which the extension portion is inserted, and the heat sink is attached to the printed circuit board. A method for attaching a heat sink to a printed circuit board, which is characterized in that the heat sink can be attached. 2. A heat sink attached to the printed circuit board, wherein a notch groove is provided in a direction along a plate surface of the printed circuit board in the vicinity of the protrusion having the extension portion in the heat sink body, and the notch is provided. The innermost part of the groove reaches a position slightly beyond the side edge on the opposite side to the extension direction of the extension part forming the protrusion, and extends from this innermost part toward the printed circuit board. The heat sink used in the method for attaching a heat sink to a printed circuit board according to claim 1, wherein the extended groove is formed. 3. A heat sink attached to the printed circuit board, wherein a notch groove is provided in a direction along a plate surface of the printed circuit board in the vicinity of the protrusion having the extension, and the deepest part of the notch groove. 2. The method for mounting a heat sink on a printed circuit board according to claim 1, wherein the portion reaches a position slightly beyond a side edge of the protrusion forming the protrusion, the side edge being opposite to the extension direction of the extension. Heat sink used for. 4. The heat sink used in the method of attaching a heat sink to a printed circuit board according to claim 1, wherein a thin portion is provided on the heat sink body along the straight line to facilitate bending.