JPH0573993U - Heat sink mounting structure - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a structure for mounting a heat dissipation plate on which a device is mounted, which can secure the mounting strength of the heat dissipation plate on the substrate and save space. [Structure] A tubular fixture 9 is fixed to an end portion of a heat dissipation plate 1 which is attached to a substrate 3, a through hole 11 is provided in the substrate 3, and the through hole 1
The heat radiating plate 1 was fixed to the substrate 3 by inserting the screw 12 into 1 and screwing it into the tubular fixture 9.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a structure for mounting a heat dissipation plate on which an element (electronic component) is mounted on a printed wiring board.

[0002]

[Problems to be solved by conventional techniques and devices]

 FIG. 3A is a perspective view showing an example of a conventional mounting structure of the heat dissipation plate 1 on which the element 2 is mounted on the printed wiring board 3, and FIG. 3B is a front view showing the main part thereof. As shown in these figures, conventionally, a notch 4 is provided at an edge of the heat sink 1 on which the heat sink 1 is attached to the substrate 3, and the head of the terminal 5 is fixed to the notch 4 by caulking. It was inserted into the hole 6 provided in the substrate 3 and fixed to the conductor of the substrate 3 by the solder 7.

However, according to this conventional structure, since the heat sink 1 is attached to the substrate 3 by the solder 7, the mechanical strength is weak, and when vibration or shock is applied to the heat sink 1 or the substrate 3, the solder is used. There is a problem in that the conductor attached with 7 may peel from the substrate 3. In particular, due to recent high-density mounting, the number of elements 2 mounted on the heat dissipation plate 1 is increased, so that the weight is increased and the peeling is likely to occur.

FIG. 3C shows another example of a conventional mounting structure for the heat sink 1, in which the mounting foot portion 1 a is provided at the edge of the heat sink 1 on the side where the heat sink 1 is mounted on the substrate 3. The structure is such that a screw 8 inserted in the hole of the substrate 3 is screwed into the hole provided in the foot portion 1a and tightened, or fixed by a rivet.

With this structure, although the mounting strength of the heat dissipation plate 1 can be secured, since the foot portion 1a is bent in a direction perpendicular to the plate surface of the heat dissipation plate 1, the foot portion 1a has a width shown by W. There is a problem that it takes up space and hinders high-density mounting.

In view of the above problems, it is an object of the present invention to provide a structure for mounting a heat dissipation plate to a substrate, which can secure the mounting strength of the heat dissipation plate to the substrate and save space.

[0007]

[Means for Solving the Problems]

 In order to achieve this object, the present invention has a structure in which a heat dissipation plate on which an element is mounted is mounted on a printed wiring board. The heat dissipation plate is fixed to the substrate by providing a through hole and inserting a screw into the through hole and screwing the screw into the tubular fixture.

[0008]

[Action]

 The present invention has the above-mentioned structure, and the heat sink is pressed against the board by screwing a screw inserted into the through hole of the board to a tubular fixture fixed to the heat sink and tightening the screw. It is tightened together in the state. In this structure, the space required for fixing is determined by the diameter of the tubular fixing device or screw.

[0009]

【Example】

 FIG. 1 (A) is an exploded perspective view showing an embodiment of a heat sink mounting structure according to the present invention, in which a cylindrical fixing member 9 is attached to the end of the heat sink 1 made of a metal such as aluminum on the substrate 3 side. A notch 10 for fitting is formed by punching. The tubular fixture 9 is made of brass, for example, and has a fixing head 9a. The notch 10 has such a shape that the body portion or the head portion of the tubular fixture 9 can be fitted from the lateral direction. Then, the tubular fixture 9 is fitted into the notch 10 and, as shown in FIG. 1 (C), for example, by pressing from both sides as shown by the arrow P, the head 9a is brought into contact with the notch 10 of the heat dissipation plate 1. Crimp. As a result, the tubular fixture 9 has a shape in which the head 9a is crushed as shown in FIGS. 1 (B) and 1 (C).

In this caulking structure, as shown in FIG. 2 (A), the portion 13 near the head 9a of the cylindrical fixing member 9 of the heat dissipation plate 1 is pressed from both sides of the plate surface to fix the cylindrical shape. As shown in FIG. 2 (B), a structure for fixing the tool 9 is provided, and caulking pieces 1b are provided on both sides below the head portion 9a of the heat dissipation plate 1, and these caulking pieces 1b are indicated by arrows. In the structure of caulking toward the head 9a, or as shown in FIG. 2 (C), the protrusion 1c is provided on the heat dissipation plate 1 and the cylindrical fixing member 9 is inserted into the protrusion 1c, and then, as shown in FIG. There are various forms such as caulking as in B), and the structure is not limited to the above.

After fixing the tubular fixing member 9 to the end portion of the heat dissipation plate 1 as described above, the tapping screw 12 is inserted into the through hole 11 provided in the substrate 3, and then, as shown in FIGS. As shown, the tapping screw 12 is screwed into the tubular fixture 9. The tapping screw 12 is deformed so as to form a thread groove on the tubular fixing member 9 and is coupled to the tubular fixing member 9, and the substrate 3 is fastened together with the heat radiating plate 1.

In this co-fastening structure, as shown in FIG. 2D, the diameter of the through hole 11 provided in the substrate 3 is set to be approximately the same as or slightly larger than the outer diameter of the tubular fixture 9. 2 (E), the tapping screw 12 is screwed into the tubular fixing tool 9 so that the tubular fixing tool 9 is clamped between the tapping screw 12 and the inner surface of the through hole 11. With such a structure, the attachment strength of the heat dissipation plate 1 to the substrate 3 becomes large.

As described above, by adopting a structure in which the heat dissipation plate 1 is fixed to the base plate 3 by the screwing structure using the tapping screw 12, problems such as peeling of a conductor pattern are caused as in the case of fixing only by soldering. Nonetheless, the mounting strength is secured. In addition, the required space for the attachment of the heat sink 1 in this embodiment is the area S of the head 12a of the screw 12 shown in FIG. 1 (B), which is in comparison with the foot 1a shown in FIG. 3 (C). It takes a very small space.

It should be noted that the present invention is not limited to the above non-soldering type, and the tapping screw 12 may be soldered to the substrate 3 to further increase the bonding strength or to establish an electrical connection. In some cases. Further, although a tapping screw having a good mounting workability is used as the screw 12, a general screw can be used instead.

[0015]

[Effect of the device]

 According to the present invention, it is not necessary to provide a mounting foot on the heat sink, the space for the conventional soldering structure of the terminal is required, and space saving can be achieved, which is a structure suitable for high-density mounting. This is especially effective for thin heat sinks that cannot be tapped in the thickness direction of the heat sink. Further, since the screw has a coupling structure, the heat sink can be firmly attached to the printed wiring board.

[Brief description of drawings]

1A is an exploded perspective view showing an embodiment of a heat sink mounting structure according to the present invention, FIG. 1B is a front sectional view showing the mounting structure, and FIG. 1C is a tubular fixture mounting structure thereof. FIG. 3D is a side sectional view showing FIG.

2 (A), (B) and (C) are front views showing another example of the mounting structure of the tubular fixing device according to the present invention;
(D), (E) is a front view showing an example of a suitable connection structure of the tubular fixture and the tapping screw in the present invention.

3A is a perspective view showing a conventional heat dissipation plate mounting structure, FIG. 3B is a front view showing a main part thereof, and FIG. 3C is a side view showing another example of the conventional structure.

[Explanation of symbols]

 1 heat sink 2 element 3 printed wiring board 9 tubular fixture 10 notch 11 through hole 12 tapping screw

Claims (1)

[Scope of utility model registration request] 1. A structure for mounting a heat dissipation plate on which a device is mounted to a printed wiring board, wherein a cylindrical fixture is fixed to an end of the heat dissipation plate on the side where the heat dissipation plate is attached to the board, and a through hole is provided in the board. A heat dissipation plate mounting structure, wherein the heat dissipation plate is fixed to the substrate by inserting a screw into the hole and screwing the screw into the tubular fixture.