Patent Application
20100116467
1. Field of the Invention
The present invention relates to a heat dissipation device incorporating heat pipes and fins, and more particularly to a combination structure of the fins which is used for combining the fins and the heat pipes together.
2. Description of Related Art
Computer electronic components, such as central processing units (CPUs), generate large amounts of heat during normal operation. If the heat is not properly dissipated, it can adversely affect operational stability of the electronic components and damage associated electronic devices. A heat dissipation device is often attached to a top surface of a CPU to dissipate heat therefrom.
Conventionally, a heat dissipation device as shown in
Due to a limited ductility of the fins 90 which are made of metallic material, a height of the collars 92, which is indicated by H1 in
What is needed, therefore, is an improved heat dissipation device which can overcome the described limitations.
A heat dissipation device includes a plurality of fins stacked together, a plurality of heat pipes extending through the fins, and solder filled in gaps between the fins and the heat pipes. Each fin includes a horizontal, flat plate defining a plurality of holes therein for extension of the heat pipes therethrough, respectively. A collar extends from a periphery of each of the holes. The collar includes a columned portion attached to an outer surface of the heat pipe, and a taper portion interconnecting the plate and the columned portion. A height of the collar approaches to a distance between two adjacent fins. The taper portion has an inner surface facing towards the heat pipe. A portion of the solder is retained in a space between the inner surface of the taper portion of the collar and the heat pipe to prevent the portion of the solder from overflowing to the horizontal, flat plate of the fin.
Other advantages and novel features of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
Many aspects of the present apparatus 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 apparatus. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
Referring to
Each fin 10 has a rectangular thin plate 11 and two flanges 12 bent downwardly from two long sides of the plate 11. The thin plate 11 is horizontal and flat. A channel 13 is defined between every two adjacent fins 10 by the flanges 12. The channel 13 has a height which is indicated by P in
Each heat pipe 20 has a round cross section. The heat pipe 20 has wick structures (not shown) formed in an inner surface thereof and working fluid (not shown) contained therein.
In assembly, the fins 10 are stacked together. The flanges 12 of each fin 10 abut against a lower, adjacent fin 10. Solder 30 is spread on inner surfaces of the columned portions 14 of the collars 16 of the fins 10. The heat pipes 20 are then inserted into the holes 19 of the fins 10. By the provision of the taper portions 15 which are located very close to the bottoms of the columned portions 14 of the corresponding upper collars 16, excessive solder 30 which is pushed out of the columned portions 14 is immediately received in the taper portions 15, thereby eliminating the possibility that the excessive solder 30 will drop on the flat plates 11. Then, the fins 10 together with the heat pipes 20 are put into an oven to be heated. The solder 30 on the heat pipes 20 and located corresponding to the columned portions 14 of the collars 16 is heated to flow. The flowed solder 30 evenly fills in gaps between the inner surfaces of the columned portions 14 of the collars 16 and the heat pipes 20. After cooled, the solidified solder 30 thermally and mechanically connects the heat pipes 20 and the columned portions 14 of the collars 16 together. The solder 30 on the heat pipes 20 and located between the columned portions 14 is heated to flow downwardly into spaces between inner surfaces of the taper portions 15 of the collars 16 and the heat pipes 20 as shown in
The formation of the taper portions 15 results in an increasing of a total height H of the collars 16 along the axial direction of the heat pipes 20. That is, the distance between bottoms of the columned portions 14 and the adjacent underlying fin 10 is decreased, which could prevent the solder 30 from spraying onto the horizontal, flat plate 11 of the adjacent underlying fin 10. Furthermore, the taper portions 15 connect to the outer surfaces of the heat pipes 20 by the solder 30 retained in the spaces therebetween. Therefore, a contact surface between the fins 10 and the heat pipes 20 is increased, which is an advantage of enhancing the heat dissipation efficiency of the heat dissipation device.
The heat pipes 20 are round in this embodiment, and the collars 16 form corresponding columned portions 14 to contact with the heat pipes 20. It is to be understood that the shape of the heat pipes 20 and the collars 16 could be potentially varied, as long as the collars 16 comprise a contacting portion attached to the heat pipes 20 and an intermediate portion interconnecting with the plate 11 and the contacting portion, wherein a cross section of the intermediate portion has a size larger than that of the contacting portion. In an alternative embodiment, the solder 30 can be replaced by thermally conductive glue. When the thermally conductive glue is used, the step of heating the fins and the heat pipes in the oven can be omitted.
It is believed that the present invention 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.
