BACKGROUND
1. Technical Field
The disclosure relates to heat dissipation devices and, more particularly, to a heat dissipation device with a fastener for fastening the heat dissipation device on a printed circuit board.
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, 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, a fastener extends through the heat sink and a printed circuit board where the electronic device is located to fasten the heat sink to the electronic device. However, before the heat sink mounted on the electronic device, the fastener is usually pre-assembled on the heat sink by an annular collar which snaps with an end of the fastener extending beyond the heat sink, for facilitating transportation. However, the collar is prone to disengage from the fastener when subjected to an outer force during transportation, resulting in falling of the fastener from the heat sink.
What is needed, therefore, is a heat dissipation device with a fastener which can overcome the limitations described.
BRIEF DESCRIPTION OF THE DRAWINGS
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.
FIG. 1 is an isometric, exploded view of a heat dissipation device in accordance with a first embodiment of the disclosure.
FIG. 2 is an assembled view of the heat dissipation device of FIG. 1, wherein a fastener of the heat dissipation device is in a released position.
FIG. 3 is a cross-sectional view of the heat dissipation device of FIG. 2, taken along line thereof.
FIG. 4 is an assembled view of the heat dissipation device of FIG. 1, wherein a fastener of the heat dissipation device is in a locked position.
FIG. 5 is a cross-sectional view of the heat dissipation device of FIG. 4, taken along line V-V thereof.
FIG. 6 is a schematic view of a conductive plate of a heat dissipation device in accordance with a second embodiment of the disclosure.
FIG. 7 is a schematic view of a conductive plate of a heat dissipation device in accordance with a third embodiment of the disclosure.
FIG. 8 is a schematic view of a conductive plate of a heat dissipation device in accordance with a fourth embodiment of the disclosure.
DETAILED DESCRIPTION
Referring to FIGS. 1-3, a heat dissipation device 100 in accordance with a first embodiment of the disclosure is shown. The heat dissipation device 100 is for dissipating heat generated by an electronic device (not shown) mounted on a printed circuit board (not shown). The heat dissipation device 100 includes a conductive plate 10, and a fastener 20 for fastening the heat dissipation device 100 on the printed circuit board.
The conductive plate 10 defines a supporting portion 14 through the conductive plate 10. The supporting portion 14 includes a hole 142, a first groove 144, and a second groove 146 communicating with the hole 142 and the first groove 144. The hole 142 extends through the conductive plate 10 and is spaced from an outer edge of the conductive plate 10. The second groove 146 is located above and coaxial with the first groove 144. The hole 142 has a diameter smaller than that of the second groove 146 but larger than that of the first groove 144. A step portion 148 is formed at a joint of the first and second grooves 144, 146.
The fastener 20 comprises a fastening element 21, and an elastic element circling the fastening element 21. In this embodiment, the elastic element is a spring 23. The fastening element 21 comprises a column-shaped pole portion 212, a circular head portion 211 extending from a top end of the pole portion 212, and a column-shaped engaging portion 210 extending from an opposite bottom end of the pole portion 212.
The pole portion 212 has a diameter smaller than that of the first groove 144. The head portion 211 has a diameter larger than the inner diameter of the spring 23. A flange 213 protrudes horizontally and outwardly from a periphery of the pole portion 212 adjacent to the engaging portion 210. The flange 213 has a diameter smaller than a diameter of the hole 142 and an inner diameter of the spring 23 but larger than a diameter of the first groove 144 of the supporting portion 14. The flange 213 extends through the spring 23. The spring 23 is sleeved on the pole portion 212 of the fastening element 21. The spring 23 has an outer diameter larger than the diameter of the hole 142 but smaller than the diameter of the second groove 146. A limiting portion 214 protrudes from the circumference of the pole portion 212 adjacent to the head portion 211. The limiting portion 214 has a diameter smaller than the inner diameter of the spring 23.
Also referring to FIGS. 4-5, in assembly, the flange 213 extends through the spring 23, so that the spring 23 is sleeved on the pole portion 212 of the fastening element 21. The flange 213 of the fastening element 21 then extends down through the hole 142 from a top side of the conductive plate 10, so that the spring 23 and the flange 213 are respectively located at top and bottom sides of the conductive plate 10, the spring 23 elastically abuts the top side of the conductive plate 10 located at a periphery of the hole 142. The fastening element 21 is then moved horizontally towards the first groove 144, whereby the pole portion 212 enters the first groove 144, the flange 213 abuts the bottom side of the conductive plate 10 located at a periphery of the first groove 144, the spring 213 is received in the second groove 146 and elastically abuts against the step portion 148. Thus, the fastener 20 is securely fastened on the conductive plate 10.
Referring to FIG. 6, a conductive plate 10a of a heat dissipation device in accordance with a second embodiment of the disclosure is shown. The conductive plate 10a defines a supporting portion 14a through the conductive plate 10a. The supporting portion 14a includes a hole 142a, a first groove 144a, and a second groove 146a communicating with the hole 142a and the first groove 144a. The second groove 146a is located above and coaxial with the first groove 144a. The hole 142a extends through the conductive plate 10a. The differences between the first embodiment and the second embodiment are in that: the hole 142a communicates with an outer edge of the conductive plate 10a.
Referring to FIG. 7, a conductive plate 10b of a heat dissipation device in accordance with a third embodiment of the disclosure is shown. The conductive plate 10b defines a supporting portion 14b through the conductive plate 10b. The supporting portion 14b includes a hole 142b, a first groove 144b, and a second groove 146b communicating with the hole 142b and the first groove 144b. The second groove 146b is located above and coaxial with the first groove 144b. The differences between the first embodiment and the third embodiment are in that: a protrusion 12b protrudes from a bottom of the conductive plate 10b corresponding to the supporting portion 14b, a concave portion 16b is defined in a top of the conductive plate 10b corresponding to the protrusion 12b, the hole 142b and the first groove 144b extend through the protrusion 12b.
Referring to FIG. 8, a conductive plate 10c of a heat dissipation device in accordance with a fourth embodiment of the disclosure is shown. The conductive plate 10c defines a supporting portion 14c through the conductive plate 10c. The supporting portion 14c includes a hole 142c, a first groove 144c, and a second groove 146c communicating with the hole 142c and the first groove 144c. The second groove 146c is located above and coaxial with the first groove 144c. The differences between the second embodiment and the fourth embodiment are in that: a protrusion 12c protrudes from a bottom of the conductive plate 10c corresponding to the supporting portion 14c, a concave portion 16c is defined in a top of the conductive plate 10c corresponding to the protrusion 12c, the hole 142c and the first groove 144c extend through the protrusion 12c.
It is believed that the disclosure 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 examples hereinbefore described merely being preferred or exemplary embodiments of the invention.