Clip for heat sink

1. Field of the Invention

The present invention relates to a clip for a heat sink, and more particularly to a clip which can readily and securely attach a heat sink to an electronic device.

2. Description of Related Art

A heat sink is usually placed in thermal contact with an electronic package such as a central processing unit (CPU), and transfers heat through conduction away from the electronic package so as to prevent over-heating of the electronic package. Usually, a heat sink is secured to an electronic package by using a clip.

Chinese patent No. 01242181.2 shows a heat sink assembly including a heat sink and a clip securing the heat sink to an electronic component mounted on a circuit board. The heat sink includes a base and a plurality of fins extending from the base. A plurality of grooves is defined between adjacent fins. Two neighboring fins located at two lateral sides of the groove in the middle of the heat sink project a pair of bulges on opposite inner walls thereof. The clip spans across the groove in the middle of the heat sink with a positioning coil received in the groove in a manner such that the positioning coil abuts against the bulges and the base of the heat sink. Two arms extending from two ends of the positioning coil have a pair of hooks engaging with the circuit board, thereby securing the heat sink to the circuit board.

When the aforementioned clip is retained in the heat sink, the clip can not move relative to the heat sink. However, there may be times when it is desirable for the clip to move relative to the heat sink.

What is needed is to provide a clip which is movably engaged with a heat sink.

In one embodiment, a clip for mounting a heat sink on a circuit board includes a positioning coil for rotatably interferingly engaging with the heat sink. Two elongated arms extend from two ends of a line bisecting the portion respectively, and a pair of hooks formed at distal portions of the two arms respectively for engaging with the circuit board.

Other advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which:

FIG. 1 is an assembled, isometric view of a clip, a heat sink, and a circuit board in accordance with a preferred embodiment of the present invention;

FIG. 2 is an isometric view of the clip of FIG. 1 ;

FIG. 3 is an exploded, isometric view of the heat sink and the circuit board of FIG. 1 ; and

FIG. 4 is a perspective view of the clip of FIG. 1 mounted to the heat sink of FIG. 1 .

Referring to FIGS. 1 and 3 , a clip 10 used for securing a heat sink 20 to a circuit board 40 in accordance with an embodiment of the present invention is shown.

The circuit board 40 includes an electronic component 42 mounted thereon and a pair of securing members 30 located adjacent opposite lateral sides of the electronic component 42 respectively. Each of the securing members 30 includes an arched catch 34 . The securing members 30 are fixed to the circuit board 40 by any means known to those familiar with the art.

The heat sink 20 includes a base 22 having a bottom face thermally contacting with the electronic component 42 , and a plurality of fins 24 extending upwardly and perpendicularly from a top face of the base 22 . The plurality of fins 24 is cut to form a closed annular slot 25 therein. Two hooked flanges 26 are formed on the top face of the base 22 at opposite sides of the slot 25 . The two hooked flanges 26 extend up from the base 22 and then bent toward the base 22 . The two hooked flanges extend up from the top face of the base 22 and then bent toward the top face of the base 22 .

The clip 10 is a wire with a positioning coil 12 bent from a middle portion thereof and the end portions of the wire are two elongated arms 14 extending from opposite points of the positioning coil 12 . The arms 14 includes a straight portion 141 directly connected to the positioning coil 12 and extending straight up relative to a plane formed by the positioning coil 12 a predetermined distance generally equal to the depth of the annular slot 25 , and a slant portion 143 extending from a distal end of straight portion in a way slantingly upwardly relative to the plane formed by the positioning coil 12 , projecting lines of the arms 14 on the plane formed by the positioning coil 12 extend away from the coil 12 in opposite directions on parallel paths. A pair of hooks 16 is formed at distal portions of the slant portions 143 of the two arms 14 for engaging with the catches 34 of the securing members 30 respectively.

Referring to FIG. 4 , in use, the clip 10 is aligned with the slot 25 of the heat sink 20 , with the two hooks 16 being positioned above corresponding securing members 30 of the circuit board 40 . The clip 10 moves downwardly towards the heat sink 20 and the positioning coil 12 is rotatably retained in the slot 25 by the protruding portions 26 . The clip 10 is rotated around the heat sink 20 until the arms 14 are generally in alignment with the securing members 30 on the circuit board 40 . The two arms 14 are deformed toward the heat sink 20 to press the heat sink 20 tightly against the circuit board 40 via the position coil 12 , then the two arms 14 are extended through the corresponding catches 34 , and the two hooks 16 engage with corresponding catches 34 to hold the clip 10 in place.

It is believed that the present embodiment and its advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the example hereinbefore described merely being a preferred or exemplary embodiment.