Patent Application
20100000715
1. Field of the Invention
The present invention relates to a heat dissipation device, and particularly to a heat dissipation device with a fastener for fastening the heat dissipation device to an electronic device.
2. Description of Related Art
It is well known that, during operation of a computer, electronic devices such as central processing units (CPUs) frequently generate large amounts of heat. The heat must be quickly removed from the electronic device to prevent it from becoming unstable or being damaged. Typically, heat dissipation device including a heat sink is attached to an outer surface of the electronic device to absorb heat from the electronic device. The heat absorbed by the heat sink is then dissipated to ambient air.
In order to keep the heat sink in intimate contact with the electronic device, the heat dissipation device includes a fastener engaging with a printed circuit board where the electronic device is located to fasten the heat sink to the electronic device. Generally, the heat sink comprises a base defining a through hole therein. The fastener comprises a pole portion, a head portion extending from an end of the pole portion and an engaging portion extending from another end of the pole portion for engaging with the printed circuit board. A spring circles the pole portion. When fastening the heat sink to the electronic device, the engaging portion of the fastener extends through the through hole of the base of the heat sink and a corresponding aperture of the printed circuit board to engage with a back plate located at a bottom side of the printed circuit board. The spring is compressed between the base and the head portion of the fastener and presses the heat sink to the electronic device. However, when the engaging portion engages with the back plate, a compressed length of the spring is invariable; thus, a spring force produced by the compressed spring is invariable and can not be adjust to meet different electronic devices or a same electronic device under different circumstances with different pressure requirements.
What is needed, therefore, is a heat dissipation device capable of producing a fastening force which is adjustable to meet different requirements.
The present invention relates to a heat dissipation device. According to a preferred embodiment of the present invention, the heat dissipation device comprises a base, a sleeve coupling with the base, and a fastener engaging with the base and the sleeve. The base defines a thread hole extending therethrough. The sleeve comprises a first portion coupling with the hole of the base and a second portion extending upwardly from an end of the first portion. The second portion is located at a first side of the base. A through hole extends through the sleeve. The fastener comprises a body portion extending through the through hole of the sleeve, a head portion extending upwardly from an end of the body portion, a foot portion extending downwardly from another end of the body portion. The head portion is located at the first side of the base. The foot portion is located at a second side of the base. A spring member is compressed between the head portion and the second portion of the sleeve. A compressed length of the spring member is capable of being varied by adjusting a coupling length of the first portion of the sleeve with the thread hole of the base.
Many aspects of the present embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
Referring to
The heat sink 10 comprises a base 11, a fin set 15 arranged on the base 11 and four heat pipes 18 connecting the base 11 and the fin set 15. The base 11 is a substantially rectangular plate having good heat conductivity. The base 11 defines two thread holes 112 in middles of two lateral opposite portions thereof. The base 11 defines four parallel grooves 118 for receiving the heat pipes 18. A cutout 115 is defined in a front side of the base 11, adjacent to front ends of the four grooves 118. The fin set 15 comprises a plurality of fins 151 assembled together. Each of the fins 151 extends a top flange (not labeled) and a bottom flange (not labeled) from top and bottom edges thereof. The bottom flanges of the fins 151 interconnect one by one to form a flat bottom face (not labeled) contacting the base 11. The fin set 15 defines two cutouts 153 corresponding to the thread holes 112, which avoid interference between the fin set 15 and the fasteners 20 when the fasteners 20 are used to secure the heat sink 10 to the printed circuit board. The fin set 15 defines four receiving slots 158 extending through each fin 151 of the fin set 15. The four slots 158 radially extend from a middle of the bottom face of the fin set 15 toward a top portion of the fin set 15. The four slots 158 have converged bottoms and diverged tops. The bottoms of the four slots 158 are opened to and in communication with corresponding grooves 118 of the base 11.
Each heat pipe 18 comprises an evaporating section (not labeled), a condensing section (not labeled) parallel to the evaporating section, and a connecting section (not labeled) connecting the evaporating section and the condensing section. The evaporating sections of the heat pipes 18 are received in the corresponding grooves 118 of the base 11 and the bottoms of the slots 158 of the fin set 15. The evaporating sections of the heat pipes 18 are parallel to each other and converged in the base 18 and the bottom of the slots 158. The condensing sections of the heat pipes 18 are parallel to each other and received in the tops of the slots 158 of the fin set 15. The connecting sections of the heat pipes 18 extend from the bottoms to the tops of the slots 158 of the fin set 15.
Referring also to
The sleeve 25 is a one-piece member and comprises an abutting portion 250 and a thread portion 255 extending downwardly from a bottom end of the abutting portion 250. A through hole 258 extends through the abutting portion 250 and the thread portion 255. In this embodiment, the abutting portion 250 has a regular-hexagonal-prism profile. The abutting portion 250 has a flat top face (not labeled) for supporting the spring 23. The thread portion 255 has a cylinder profile. The thread portion 255 is machined with a plurality of threads on a circumferential periphery thereof, for coupling with the thread hole 112 of the base 11. The through hole 258 has an upper portion surrounded by the abutting portion 250 and having a hexagonal profile, and a lower portion surrounded by the thread portion 255 and having a cylindrical profile.
Referring also to
The foot portions 218 further extend through corresponding through apertures defined in the printed circuit board and engage with a back plate located under the printed circuit board. Here, as shown by
Referring also to
It is believed that the present embodiments and their 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 examples hereinbefore described merely being preferred or exemplary embodiments of the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 200810068321.X | Jul 2008 | CN | national |
