JPH0573994U - 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 screw engagement portion 9 is formed at an end of a heat dissipation plate 1. The screw-threaded portion 9 is composed of push-bent portions 9 a and 9 b protruding from the plate surface of the heat dissipation plate 1. The heat sink 1 is fixed to the substrate 3 by inserting the screw 10 into the through hole 11 provided in the substrate 3 and screwing the screw 10 into the screw engagement portion 9. As the screw-engagement portion, a pair of bent pieces that are deformed in the direction in which they project from the plate surface of the heat dissipation plate 1 in opposite directions and that face each other may be provided. Further, instead of the push-bend portions 9a and 9b as the screw-threaded portions, a cutout may be formed at the end of the heat dissipation plate.

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. 4 (A) is a perspective view showing an example of a conventional mounting structure of the heat dissipation plate 1 mounting the element 2 on the printed wiring board 3, and FIG. 4 (B) 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. 4C shows another example of a conventional mounting structure for the heat sink 1, in which the mounting foot 1 a is provided on 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 into 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 sink for mounting an element is mounted on a printed wiring board. A hole is provided, and a screw is inserted into the through hole and screwed into the screw threaded portion to fix the heat dissipation plate to the substrate, and the screw threaded portion is formed from the plate surface of the heat dissipation plate. It is characterized by comprising a protruding push-bent portion. In the present proposal, instead of the push-bend portion, a pair of bending pieces may be provided which are deformed in a direction projecting from the plate surface of the heat dissipation plate and face each other, and the end of the heat dissipation plate is provided. The structure may have a notch formed in the portion.

[0008]

[Action]

 The present invention has the above-mentioned structure, and the heatsink is attached to the board by screwing the screw inserted into the through hole of the board to the screw-threaded portion formed integrally with the heatsink. It is tightened together while being pressed. In this structure, the space required for fixing is determined by the screw threaded portion or screw diameter.

[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 screw screwing portion 9 is provided at an end of the heat sink 1 made of a metal such as aluminum on the substrate 3 side. It is formed by punching and press molding. The screw-threaded portion 9 is composed of a plurality (two in this example) of press-bent portions 9a and 9b which are deformed in a direction in which the heat-dissipating plate 1 protrudes from the plate surface. A screw engagement portion is formed between the push-bend portions 9a and 9b.

A through hole 11 is provided in the substrate 3, and a tapping screw 10 is inserted into the through hole 11 as shown in FIGS. 1B and 1C, and the tapping portion 9 is tapped. The heat sink 1 is fixed to the substrate 3 by screwing in the screws 10.

In this structure, since the heat dissipation plate 1 is fixed to the base plate 3 by the screwing structure using the tapping screw 10, there is no problem such as peeling of the conductor pattern as in the case of only soldering, and the mounting strength is high. Is secured. Further, the required space for the attachment of the heat dissipation plate 1 in this embodiment is the area S of the head portion 10a of the screw 10 shown in FIG. 1 (B), which is compared with the foot portion 1a shown in FIG. 4 (C). And it takes a very small space. Further, the number of parts does not increase as compared with the conventional case.

When the screw-threaded portion 9 is formed by forming the push-bend portion, the push-bend portion 9c is formed to have a horizontal cross-sectional shape of a semi-circular arc or more, as shown in FIG. 1D. In this case, the number of push-bends 9c is one, and it is not necessary to form a plurality of push-bends. It should be noted that the present invention is not limited to the above non-soldering type, and the tapping screw 10 may be soldered to the substrate 3 to further increase the bonding strength or to establish an electrical connection. .

FIG. 2A is a partial perspective view of a heat dissipation plate showing another embodiment of the present invention, FIG. 2B is a front sectional view showing a mounting state, and FIG. It is a cross-sectional view. In the present embodiment, instead of the push-bend portion 9, a pair of bent pieces 12a, 12b which are deformed in a direction projecting from the plate surface of the heat dissipation plate 1 and are opposed to each other are provided to perform tapping. The threaded portion 12 of the screw 10 is used. Also in this embodiment, it is possible to save space and improve the bonding strength by the screwing structure.

FIG. 3A is a partial perspective view of a heat dissipation plate showing another embodiment of the present invention, FIG. 3B is a front sectional view showing a mounting state, and FIG. It is a cross-sectional view, and in the present embodiment, a cutout 13 is provided at an end of the heat dissipation plate 1 on the substrate mounting side instead of the push-bend portion 9, and the tapping screw 10 is screwed into the cutout 13. The present embodiment has a structure that is suitable when the thickness of the heat dissipation plate 1 is large, and has the advantages that the same effects as described above can be obtained and that the screw-threaded portion 13 can be easily processed. . Further, the thickness of the portion where the notch 13 is provided may be increased.

In the above-mentioned embodiment, a tapping screw having a good mounting workability is used as the screw 10, but a general screw can be used instead.

[0016]

[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. In addition, the number of parts will not increase compared to conventional products.

[Brief description of drawings]

FIG. 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 state, and FIG. Cross section,
(D) is a perspective view showing a modification of the present embodiment.

2A is a perspective view of a radiator plate showing another embodiment of a radiator plate mounting structure according to the present invention, FIG. 2B is a front sectional view showing the radiator plate mounting state, and FIG. ) F-
FIG.

3A is a perspective view of a radiator plate showing another embodiment of the radiator plate mounting structure according to the present invention, FIG. 3B is a front sectional view showing the radiator plate mounting state, and FIG. ) G-
It is a G sectional view.

FIG. 4A is a perspective view showing a conventional heat dissipation plate mounting structure, FIG. 4B is a front view showing a main part thereof, and FIG. 4C is a side view showing another example of the conventional structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat sink 2 Element 3 Printed wiring board 9 Screw screwing parts 9a, 9b Push bending part 10 Tapping screw 11 Through hole 12 Screw screwing part 12a, 12b Bent piece 13 Notch

Claims (3)

[Scope of utility model registration request] 1. A structure for mounting a heat dissipation plate on which an element is mounted to a printed wiring board, wherein a screw threaded portion is formed at an end portion of the heat dissipation plate on which the heat dissipation plate is attached to the board, and a through hole is provided in the board. By inserting a screw into the hole and screwing it into the screw threaded portion, there is a structure for fixing the heat dissipation plate to the substrate, and the screw threaded portion is formed from a pressing bent portion protruding from the plate surface of the heat dissipation plate. The heat sink mounting structure is characterized by: 2. A pair of bending pieces, which are deformed in a direction projecting from the plate surface of the heat radiating plate and are opposed to each other, in place of the push-bend part as the screw-threaded part. The heat sink mounting structure is characterized in that 3. The mounting structure for a heat radiating plate according to claim 1, wherein a notch is formed at an end of the heat radiating plate instead of the push-bend portion as the screw threaded portion.