JPH06177554A - Fixing method for heat dissipating plate to printed board - Google Patents

Abstract

PURPOSE:To provide a method of surely and firmly fixing a heat dissipating plate to a printed board even if the heat dissipating plate is formed of material which can not be soldered. CONSTITUTION:A square hole 10 is provided to a printed board 3, and an engaging pawl 8 provided to a heat dissipating plate 7 is inserted into the square hole 10 to mount the heat dissipating plate 7 on the printed board 3, wherein an auxiliary hole 11 is provided to the square hole 10 of the printed board 3 crossing it at a right angle. An engaging pawl 8, which is provided with a cutout 9 at its root and whose tip is tapered and tilted inwards or outwards, is provided to the lower part of the heat dissipating plate 7, the engaging pawl 8 is fitted to the square hole 10 of the printed board 3 and pressed against it, whereby the engaging pawl 8 is elastically deformed and inserted into the square hole 10, then the pawl 8 is made to recover its original shape, and the cutout 9 provided to the engaging pawl 8 is fitted to the auxiliary hole 11 of the square hole 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for fixing a heat dissipation plate and a printed circuit board, and more particularly to a method for fixing the heat dissipation plate and the printed circuit board which is effective when a heat dissipation plate which cannot be soldered is used.

[0002]

2. Description of the Related Art As an example of a conventional method for fixing a heat dissipation plate to a printed circuit board, as shown in FIG. Claw 2
Is inserted into the square hole 4 of the printed circuit board 3, and the locking claw 2
The heat sink 1 is attached to the printed circuit board 3 by pressing the hole wall of
The lead terminals 6 of the heat-generating component 5 such as a power transistor fixed to the heat sink 1 are soldered to the pattern of the printed circuit board 3 to make them conductive. In addition, a method of screwing and fixing a heat dissipation plate to a printed circuit board with screws or the like is also performed.

[0003]

By the way, among the above-mentioned conventional fixing methods, in the method of fixing the heat radiating plate by using the locking claws, the number of parts is small and the number of man-hours for fixing the heat radiating plate is small. If you use iron, copper, etc. that can be soldered as the material, you can achieve strong fixation by fixing it to the printed board with solder via the locking claws, but if you use copper for the heat sink, the cost will increase, If iron is used,
Both of them are unsuitable because they have poor thermal conductivity. On the other hand, when aluminum is used, it is suitable in terms of cost and thermal conductivity, but it cannot be fixed by soldering, and the heat radiation plate shown in FIG. When a force is applied in the direction, there is a problem that it will come off from the printed circuit board. Further, in the case of fixing the heat dissipation plate to the printed circuit board by using screws or the like, there is a problem that the number of parts increases, the number of steps for fixing is increased, and the cost increases.

The present invention has been made in view of the above problems of the prior art. When the heat sink is made of a material such as low-cost aluminum that cannot be soldered, the heat sink and the printed circuit board are fixed to each other. The purpose of the present invention is to provide a fixing method that securely and firmly secures.

[0005]

A method of fixing a heat dissipation plate and a printed circuit board according to the present invention comprises providing a rectangular hole in the printed circuit board,
In a method of fixing a heat dissipation plate and a printed board by inserting a locking claw provided on the heat dissipation plate into the square hole to attach the heat dissipation plate to the printed board, an orthogonal auxiliary hole is formed in the square hole of the printed board, On the lower part of the heat dissipation plate, there is provided a locking claw with a tip inclined inward or outward and tapered, and having a notch on the base side, and the locking claw is fitted in the square hole of the printed circuit board. The pressing claw is elastically deformed to be inserted into the square hole, and thereafter the deformation is restored, and the notch provided in the locking claw is fitted to the auxiliary hole of the square hole.

[0006]

According to the method of fixing the heat dissipation plate and the printed circuit board of the present invention, the rectangular auxiliary holes are formed in the rectangular holes of the printed circuit board, and the tip end portion is inclined inward or outward at the lower part of the heat dissipation plate. , And provided with a locking claw that is formed in a tapered shape and has a notch on the base side, and the locking claw is elastically deformed by inserting the locking claw into the square hole of the printed board and pressing it, and then inserting into the square hole. , The deformation is restored, and the notch of the locking claw is fitted into the auxiliary hole of the square hole. In this way, by pressing the heat dissipation plate against the printed circuit board, the locking claws were restored and fitted into the auxiliary holes, and the locking claws of the heat dissipation plate were locked to the printed circuit board. As a result, the heat radiating plate is fixed to the printed circuit board, and the heat radiating plate is less likely to come off without being fixed with solder, and the locking claws are less likely to come off even if the heat radiating plate is pulled upward or the upper portion is pushed laterally. On the other hand, the heat radiating plate can be removed from the printed circuit board by elastically deforming the locking claws, lifting them upward, and removing the locking claws.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 are views for explaining a first embodiment of a method for fixing a heat sink and a printed board according to the present invention. As shown in FIGS. 1 and 2, the heat dissipation plate 7 is formed by bending a plate made of aluminum, for example, and forming a planar shape into a U shape, and inward at the lower parts of the U-shaped legs (direction surrounded by the U shape). The locking claw 8 is formed in a tapered shape by inclining the tip to a circular arc shape, and a notch 9 is provided on the base side of the locking claw 8. The printed circuit board 3 is provided with a square hole 10 into which the locking claw 8 is inserted.
The auxiliary hole 11 is formed in an orthogonal shape by providing a step to widen the width. The size of the auxiliary hole 11 in the longitudinal direction is larger than the width of the locking claw 8 of the heat dissipation plate 7 and smaller than the base portion excluding the notch 9.

In the method of fixing the heat dissipation plate 7 and the printed circuit board 3 of this embodiment, first, the locking claws 8 and 8 provided on the lower part of the heat dissipation plate 7.
The tip of the is fitted into the square holes 10, 10 of the printed circuit board 3 and pushed. As a result, the locking claw 8 is pressed against the wall of the square hole 10 and pushed in while elastically deforming, and when the lower surface of the main body of the heat dissipation plate 7 reaches the surface of the printed circuit board 3, the deformation of the locking claw 8 is restored. The base of the locking claw 8 fits into the auxiliary hole 11 of the square hole 10 (FIG. 2). By simply pressing the heat radiating plate 7 in this way, the locking claws 8 are elastically deformed, fit into the auxiliary holes 11 of the square holes 10 of the printed circuit board 3, and the notches 9 are fitted into the lower surface of the printed circuit board 3, so that the solder Even if it is not attached, if it is pulled up as it is, it will be difficult to pull it out, and if the upper part is pushed laterally, the locking claw 8 will not easily come off, and the heat dissipation plate 7 can be prevented from tilting and coming off. When removing the locking claws 8 of the heat radiating plate 7, as shown in FIG. 3, a force in the direction (Y, Y direction) opposite to the inclination of the locking claws 8 is applied to the heat radiating plate 7. In addition, the locking claw 8 may be elastically deformed, displaced from the step, and pulled out.

As described above, according to this embodiment, when the heat sink 7 is attached to the printed circuit board 3, the locking claws 8 are simply pushed into the square holes 10 of the printed circuit board 3 without slipping. Also, the locking claws 8 of the heat sink 7 are locked to the printed circuit board 3, and can be easily fixed to the printed circuit board 3 by the clinch type.
The heat dissipation plate 7 can be securely fixed without using solder.
On the other hand, the heat radiating plate 7 can be removed from the printed circuit board 3 by elastically deforming the locking claws 8 to lift the heat radiating plate 7 upward and releasing the fitting of the locking claws 8.

FIG. 4 is a diagram showing another embodiment of the method of fixing the heat dissipation plate and the printed circuit board according to the present invention. In the heat dissipation plate 12 of the present embodiment, the locking claws 13 are formed so that the lower parts of the U-shaped legs are outwardly inclined (the direction away from the portion surrounded by the U-shape) and the tips are thinned in an arc shape. The locking claw 13 is provided with a notch 14 on the base side thereof. The printed circuit board 3 is provided with a square hole 15, and an auxiliary hole 16 is formed in the square hole 15 in an orthogonal manner. The auxiliary hole 16 narrows the portion where the notch 14 of the locking claw 13 of the heat dissipation plate 12 fits. According to this embodiment, similarly to the first embodiment, when the locking claw 13 is inserted into the square hole 15 of the printed circuit board 3, it is elastically deformed and inserted. It restores its shape and fits into the stepped portion of the square hole, making it difficult to pull out.

The present invention is not limited to the above embodiment. For example, the locking claw may have a polygonal shape such as a polygonal shape, instead of an arcuate tip. The point is that the locking claws extend obliquely downward, elastically deform during mounting, and then the shape restores, so that the base side of the locking claws fits into the auxiliary holes of the square holes, and at the same time the notches are formed in the printed circuit board. It only has to be fitted.

[0012]

As described above, according to the method of fixing the heat dissipation plate and the printed circuit board according to the present invention, the heat dissipation plate can be fixed to the printed circuit board by one-touch with the clinch method, which is easy and the fixation is strong. It can be more difficult to pull out than the one-touch type fixing method.

[Brief description of drawings]

FIG. 1 is a perspective view for explaining an embodiment of a method of fixing a heat dissipation plate and a printed board according to the present invention.

2A and 2B are views showing the main part of the embodiment, in which FIG. 2A is a sectional view taken along line AA in FIG. 1, FIG. 2B is a sectional view taken along line BB, and FIG. FIG.

FIG. 3 is a plan view showing a direction of force when the heat dissipation plate of the above embodiment is removed.

FIG. 4 is a view for explaining another embodiment of the method of fixing the heat sink and the printed circuit board according to the present invention, in which (a) is a plan view,
(B) is a front view and (c) is a side view of the locking claw.

FIG. 5 is a perspective view showing a conventional method of fixing a heat sink.

FIG. 6 is a side view for explaining a state in which a heat dissipation plate is removed by a conventional fixing method.

[Explanation of symbols]

3 Printed circuit board 7,12 Heat sink 8,13 Locking claw 9,14 Notch 10,15 Square hole 11,16
Auxiliary hole

Claims (1)

[Claims] 1. A method of fixing a heat dissipation plate and a printed circuit board, wherein the heat dissipation plate is attached to the printed circuit board by inserting a locking claw provided in the heat dissipation plate into the square circuit board. An orthogonal auxiliary hole is formed in the square hole, and a locking claw having a notch on the base side is formed at the lower end of the heat dissipation plate, the tip of which is inclined inward or outward, and which is tapered. The locking claw is elastically deformed by inserting the locking claw into the square hole of the printed circuit board and pressing it into the square hole, and then the deformation is restored, and the notch provided in the locking claw in the auxiliary hole of the square hole. A method for fixing a heat dissipation plate and a printed circuit board, characterized in that: