GB2184887A

GB2184887A - Heat sink

Info

Publication number: GB2184887A
Application number: GB8629541A
Authority: GB
Inventors: Peter Martin Law
Original assignee: Marston Palmer Ltd
Current assignee: Marston Palmer Ltd
Priority date: 1985-12-21
Filing date: 1986-12-10
Publication date: 1987-07-01
Also published as: GB8629541D0; GB8531565D0

Abstract

A heat sink for cooling electronic devices, the heat sink being formed in two parts 2, 3, each part being an aluminium extrusion, the two parts being adapted to interlock together and to trap the electronic device 1 between them to co-operate together to form the heat sink. As shown the part 3 has a pair of hook members 15, 16 which lock onto detents 13, 14 by snap action. Part 2 has fins 7, 8. In an alternative embodiment the two parts lock together by a ratchet action. <IMAGE>

Description

SPECIFICATION Heat sink This invention relates to heat sinks and has particular, but not exclusive, reference to heat sinks for cooling electronic devices.

Heat sinks are well known for cooling electronic devices which generate heat during operation. In many cases the amount of heat generated is such that the device would be damaged or cease to operate accurately if it were not cooled. Most electronic devices which require cooling are attached to a metallic conductor, which conductor dissipates heat by conduction, convection or radiation.

Numerous types of heat sinks have been devised and many types are formed of aluminium extrusion. Thus there is disclosed in British Patent Application 2 079 052 a heat sink comprising a base member with a series of upstanding fins which enhance the surface area of the heat sink to enhance the effectiveness of the heat sink in removing heat from an electronic device.

There has also been proposed the concept of an aluminium extruded heat sink connected to an electronic device by means of a spring clip which may be formed of a plastics material, see for example British Patent Specification 1 316 086.

By the present invention there is provided a heat sink for cooling an electronic or other device, the heat sink including two sections, both sections being formed of aluminium or an aluminium alloy by extrusion, the two sections being adapted and arranged to interlock together and to trap between them the device to be cooled.

The two sections may snap together or may lock together by a ratchetting action.

One at least of the sections may include at least one resilient member adapted to maintain pressure on the device and to maintain it in full contact with the other section.

One or both of the sections may be provided with a plurality of fins to increase the surface area of the device and to enhance heat exchange relationship. One or both of the sections may be provided with means to permit that section to be secured to a support board. The means may comprise a hole or a tab.

By way of example embodiments of the present invention will now be described with reference to the accompanying drawings of which: Figure 1 is a cross-section of one embodiment of the invention; Figure 2 is a cross-section of a second embodiment of the invention showing a device in situ; Figure 3 is a cross-section of a third embodiment of the invention showing a device in situ; and Figure 4 is a cross section of a fourth embodiment of the invention showing a device in situ.

Referring to Fig. 1 this shows an electronic device such as an integrated circuit 1 trapped between two parts of the heat sink assembly 2 and 3. The section 2 forms the main body of the heat sink and has a planar central region 4 with end regions 5 and 6. The end regions include a number of upstanding fins 7, 8. A pair of fins 9, 10 are provided with a camming surface 11, 12 and a detent locking surface 13, 14. The second section 3 has a pair of hooks 15, 16 which run down the camming surfaces 11, 12 and lock onto the detent surfaces 13, 14. The section 3 includes a pair of longitudinally extending leg members 17, 18 which co-operate with the central region 4 to trap the electronic device 1.

It can be seen that both sections 2 and 3, which are formed of aluminium by extrusion, may be easily manufactured by a suitable die and may be easily attached to the device 1.

Holes 19, 20 can be provided in the section 2 to enable it to be attached to a suitable support board.

Numerous pairs of sections may be provided as is shown in Figs. 2, 3 and 4. Thus referring to Fig. 2 the main section 21 has a pair of inwardly formed ribs or fins 22, 23 which have a curved surface so as to be capable of locking in a second section 24 to trap an electronic device 25.

As shown in Fig. 3 the curved fins may be provided on the section 26 in the outer position 27, 28. The second section 29 then is provided with an inwardly directed V shaped portion 30 to trap the electronic component 31 when the legs 32, 33 are sprung over the fins 28, 27.

Rather than using a snap lock system as shown in Figs. 1 to 3 a ratchet type system may be provided as is illustrated in Fig. 4. In this case the fins 34, 35, 36, 37 of Section 38 form parallel channels into which the legs 39, 40 of the second section 41 are pushed.

The legs 39, 40 carry inclined angular portions 42, 43 which ratchet down between the fins of section 38 to lock sections 38 and 41 together. Again as electronic device 44 is trapped between the two sections so as to be maintained fully in contact with the section 38.

It will be appreciated that with the devices illustrated in Figs. 1 and 2 two electronic devices may be connected back to back on the same heat sink.

Claims

1. A heat sink for cooling an electronic or other device, the heat sink including two sections, both sections being formed of aluminium or an aluminium alloy by extrusion, the two sections being adopted and ranged to in terlock together and to trap between them the device to be cooled.

2. A heat sink as claimed in claim 1 in which the two sections snap together.

3. A heat sink as claimed in claim 1 in which the two sections lock together by a ratchetting action.

4. A heat sink as claimed in any one of claims 1 to 3 in which at least one of the sections includes at least one resilient member adopted to maintain pressure on the device and to maintain it in full contact with the other section.

5. A heat sink as claimed in any one of claims 1 to 4 in which one or both sections are provided with a pulurality of fins to increase the surface area of the device and to enhance heat exchange relationship.

6. A heat sink as claimed in any one of claims 1 to 5 in which one or both of the sections is or are provided with means to permit that section to be secured to a support board.

7. A heat sink as claimed in claim 6 in which the means comprises a hole or tab.

8. A heat sink for cooling an electronic or other device substantially as herein described with reference to and as illustrated by Fig. 1 or Fig. 2 or Fig. 3 or Fig. 4 of the accompanying drawings.