JPH1197594A - Heat sink fixing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat sink having improved durability and higher reliability with no problem as to electrical connection regardless of the weight and the use environment of the heat sink. SOLUTION: A heat sink base 1 is provided with a plurality of pins 4 on the lower part thereof and a component mounting hole 3 for object component 5 at nearly central part thereof, and a printed board 9 is provided with pin inserting holes 10 at the positions corresponding to a plurality of pins. Moreover, the object component 5 is provided with means 6 for fixing it to the heat sink base 1 and solder balls 7 on the side to which the printed board is to be mounted. Further, an above-mentioned plurality of pins 4 are threaded in the upper parts thereof and grooved for a driver or a wrench in the bottom surfaces thereof. Further, this plurality of pins 4 are tapered at the lower parts thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat sink fixing device for fixing a heat sink to a printed board having a mounting component such as a semiconductor.

[0002]

2. Description of the Related Art In recent years, with the advance of integrated circuit technology, LS
Although the integration and speed of I-chips are being promoted, the amount of heat generated tends to increase in high-performance processors and the like. Accordingly, it is essential to mount a heat sink for stable operation by heat radiation. Are coming.

Conventionally, there are three types of devices for fixing a heat sink of this type to a printed circuit board, namely, a first device.
A device for directly fixing a heat sink to a printed circuit board mounted part using screws, springs, adhesives, and the like; a second device for directly fixing a heat sink to a printed circuit board with screws; and a third device. There is a device for fixing a heat sink to a printed board using a metal spring-like material.

[0004]

However, only the fixing method using the above-described fixing device causes many problems in durability and electrical aspects.

For example, in the first fixing device, since the heat sink is simply fixed to the component by screws or the like, the weight of the heat sink is added to the weight of the component, and a solder portion for fixing the component to the printed circuit board is provided. All loads are applied to the

Accordingly, DIP (Dual In-lin)
e Package), PGA (Pin Grid)
In the case where the components are soldered to the printed board by the leads as in (Array), there is no problem.
SOS (Small Outline Package)
e) and QFP (Quad Flat Package)
In the case of soldering by surface mounting such as BGA (Ball Grid Array) and the like, since the bonding force by the solder portion is weak, especially when the printed circuit board is vertically mounted or used in an environment with a lot of vibration. Problems such as cracks occurring in the solder due to long-term use occur.

In the second fixing device, the weight of the heat sink is transmitted to the printed circuit board via the screw, so that the load on the component itself is reduced. The package of the component may be warped, and the solder fixing portion and the component itself have an influence on the electrical connection.

Further, in the third fixing device, the connection between the heat sink and the components and the printed board is weaker than other devices, and the heat sink is rarely used for a heavy heat sink.

SUMMARY OF THE INVENTION An object of the present invention is to provide a highly reliable heat sink fixing device which is excellent in durability and does not cause a problem in electrical connection irrespective of the weight and use environment of the heat sink.

[0010]

According to the heat sink fixing apparatus of the present invention, a plurality of fins are implanted on an upper surface of a base, and a plurality of pins are implanted on a lower surface of the base, respectively. A heat sink having holes formed therein, and a printed circuit board having pin insertion holes formed at positions corresponding to the plurality of pins are provided.

Further, in the heat sink fixing device of the present invention, the heat sink is attached to the target component by inserting fixing means provided at a position corresponding to the target component for mounting the heat sink into the component mounting hole of the heat sink base. It is characterized by being fixed.

Further, in the heat sink fixing device of the present invention, the target component is fixed to the printed circuit board side by a solder ball.

Further, in the heat sink fixing device of the present invention, the plurality of pins implanted in the heat sink base are threaded at an upper portion thereof, and a groove for a driver or a wrench is formed at a lower end surface thereof. It is characterized by the following.

Further, in the heat sink fixing device of the present invention, the plurality of pins implanted in the heat sink base are threaded at an upper part thereof, and a lower part is tapered. is there.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a top view showing an embodiment of a heat sink used in the present invention, and FIG. 2 is a side view of the heat sink shown in FIG.

In FIG. 1, a large number of fins (wings) 2 are erected on the upper surface of a base 1 constituting a heat sink, and the fins 2 may have various shapes. A columnar one is employed.

The diagonal line of the heat sink base 1 is
Each component mounting hole 3 is provided. These are used to pass screws for coupling to a component such as an IC to which a heat sink is attached, which will be described later.

Further, as shown in FIG. 2, four phone pins 4 are provided at four corners of the lower surface of the heat sink base 1.

A procedure for fixing the component to be mounted on the heat sink having such a configuration will be described with reference to FIGS.

FIG. 3 is an exploded perspective view of a heat sink (FIG. 1), components such as ICs, and a printed circuit board according to the present invention, and FIG. 4 shows a state in which the heat sink, the components, and the printed circuit board have been assembled. It is a side view.

In FIGS. 3 and 4, FIGS.
The same components as those described above are denoted by the same reference numerals, and detailed description is omitted.

In FIG. 3, two screws 6 are implanted on the upper surface of a target component 5 such as an IC for attaching a heat sink, and a solder ball 7 is fixed on the lower surface. The target component 5 is the heat sink base 1
The nut 8 is attached by tightening.

A printed circuit board 9 on which the target component 5 is mounted
A pin insertion hole 10 having the same diameter or a slight clearance as the pin 4 is formed in a portion where the pin 4 is inserted.

Next, a procedure for mounting the heat sink, the target component and the printed circuit board having such a configuration will be described.

First, the component 5 is soldered to the printed circuit board 9 by the solder ball 7.

Next, a screw 6 buried in the upper surface of the component 5 is inserted into the component mounting hole 3 formed in the heat sink base 1, and the screw 6 is tightened with a nut 8. Fixed to.

When the screw 6 is inserted into the component mounting hole 3, the four pins 4 are inserted while being adjusted so as to enter the pin insertion hole 10 formed in the printed circuit board 9.

FIG. 4 shows a state where the component 5 is mounted on the heat sink in the above procedure.

As is apparent from FIG. 4, even when the printed circuit board 9 is vertically mounted on an electronic device (not shown), the load of the heat sink base 1 and the component 5 is distributed to the pins 4 and the printed circuit board 9 is mounted. Is hardly applied to the solder balls 7 and the surface 9 of the printed circuit board 9
A is less affected by horizontal vibration and impulses.

Next, another embodiment of the present invention will be described with reference to FIGS.

FIG. 5 is a top view of the heat sink, FIG. 6 is a configuration diagram of the pins, (A) is a side view, and (B) is a bottom view.

In FIGS. 5 and 6, FIGS.
The same components as those described above are denoted by the same reference numerals, and detailed description is omitted.

In FIG. 5, a tap is cut in the pin fixing hole 11 of the heat sink base 1, and the pin 4 is shown in FIG.
The upper part 4A is a screw as shown in FIG. Further, as shown in FIG. 6B, a groove 4B like a screwdriver or a wrench is cut in the lower part of the pin 4.

As described above, the pin fixing hole 1 with the tapped
If a plurality of pin insertion holes 10 (FIG. 3) are provided on the heat sink substrate 1 at a plurality of locations and the printed circuit board (FIG. 3) side is also provided so as to correspond to component mounting conditions, component mounting can be achieved. The pins 4 can be inserted only into the portions corresponding to the condition (1), and the heat sink 1 can be freely mounted, and the degree of freedom in mounting the heat sink 1 increases accordingly.

Next, the improvement of the matching between the pins 4 and the pin insertion holes 10 of the printed circuit board 9 (FIG. 3) will be described.

7 and 8 show another embodiment of the pin 4. FIGS. 7 and 8 show (A) a side view and (B) a bottom view, respectively.

The pin 12 shown in FIG.
The lower part 12B of the pin 13 shown in FIG.
Has a tapered shape whose diameter decreases downward.

The grooves 12C and 1C shown in FIGS.
3C is the same type as the groove 4B in FIG.

Thus, the lower wide tapered pin 12
And the lower narrow tapered pin 13 can be used to adjust the diameter error between the pin 4 and the pin insertion hole 10 (FIG. 3) of the printed circuit board 9 (FIG. 3). The consistency has been improved.

[0041]

According to the present invention described above, the printed circuit board is vertically mounted on the electronic device by separating the means for mounting and fixing the heat sink and the printed circuit board from the means for mounting and fixing the printed circuit board and components. Even
The load applied to the solder joint of the component can be greatly reduced, and the same effect can be obtained in the solder joint of the component by dispersing the influence of the impact on the pins in front and back and left and right vibrations. In addition, the electrical life of the solder joint can be extended and its reliability can be improved.

Further, since the position and the number of pins can be changed by separating the heat sink from the pins, one kind of heat sink can be used for a plurality of printed circuit boards.

Further, by making the shape of the pin tapered, it is possible to easily adjust the error with the hole diameter of the printed circuit board, and it is possible to further increase the degree of freedom in mounting.

[Brief description of the drawings]

FIG. 1 is a top view showing an embodiment of a heat sink used in the present invention.

FIG. 2 is a side view of the heat sink shown in FIG.

FIG. 3 is an exploded perspective view of the heat sink fixing device according to the embodiment of the present invention.

FIG. 4 is a side view of the heat sink fixing device according to the embodiment of the present invention.

FIG. 5 is a top view showing another embodiment of the heat sink fixing device of the present invention.

6A and 6B are diagrams showing a configuration of a pin used in the embodiment of FIG. 5, wherein FIG. 6A is a side view and FIG. 6B is a bottom view.

7A and 7B are diagrams showing another configuration of the pin used in the heat sink fixing device of the present invention, wherein FIG. 7A is a side view and FIG. 7B is a bottom view.

8A and 8B are diagrams showing still another configuration of the pins used in the heat sink fixing device of the present invention, wherein FIG. 8A is a side view and FIG. 8B is a bottom view.

[Explanation of symbols]

 1 ………………… Heat sink base 2 ………………… Fins 3, 10 …………… Pin insertion holes 4 ………………… … Pins 4B, 12C, 13C… Grooves 5 ………………………… Parts 6 …………………………… Screws 7 ……………………………… Solder ball 8 ……………………… Nut 9 ……………………… Printed circuit board 12 ……………………… Tapered pin 13 ……………… ………… Tapered pin

Claims (5)

[Claims] 1. A heat sink having a plurality of fins implanted on an upper surface of a substrate, a plurality of pins implanted on a lower surface of the substrate, and a component mounting hole formed substantially at a center of the substrate.
A printed circuit board having pin insertion holes formed at positions corresponding to the plurality of pins. 2. The heat sink is fixed to the target component by inserting fixing means provided at a position corresponding to the target component to which the heat sink is to be mounted into the component mounting hole of the heat sink base. 1
The heat sink fixing device as described in the above. 3. The heat sink fixed printing apparatus according to claim 2, wherein the target component is fixed to the printed circuit board side by a solder ball. 4. The plurality of pins implanted in the heat sink base are threaded at an upper portion thereof, and a groove for a driver or a wrench is formed at a lower end surface thereof. Heat sink fixing device. 5. The heat sink fixing device according to claim 4, wherein the plurality of pins implanted in the heat sink base are threaded at an upper part thereof, and a lower part thereof is tapered.