Heat Sink

Abstract

The heat sink includes a fin set and a heat pipe. The fin set is composed of a plurality of fins and has an exposed area formed on one side thereof. The heat pipe penetrates through the fin set and the exposed area. A portion of the heat pipe is exposed and flattened in the exposed area. The exposed and flattened portion is used for connecting a heat generating device as a thermal junction surface.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent application Ser. No. 11/492,660, filed Jul. 26, 2006.

BACKGROUND OF THE INVENTION

1. Technical Field

The invention relates to heat sinks, particularly to heat sinks for electronic components.

2. Related Art

FIG. 1 shows a typical heat sink for an electronic component. This heat sink 1 includes a heat pipe 11, a seat 13 and a fin set 12. The heat generated by the electronic component 2 is transferred to the fin set 12 via the seat 13 and heat pipe 11. In further detail, the seat 13 is penetrated by the heat pipe 13 and the heat pipe 13 is not in direct contact with the electronic component 2. The heat transferred by the heat pipe 11 must be conducted through the seat 13. Thus the heat transfer efficiency is not good enough.

FIG. 2 shows another typical heat sink. The seat 14 of the heat sink is provided with grooves 15 and slots 16 orthogonal thereto. The grooves 15 and slots 16 accommodate the heat pipes 17 and fins 18, respectively. Similarly, this heat sink also uses a seat to be a medium between heat pipes and a heat generating device. There is the same problem as the heat sink shown in FIG. 1.

SUMMARY OF THE INVENTION

An object of the invention is to provide an improved heat sink, which makes a heat pipe be in direct contact with a heat generating device. Thus the heat from the device may be directly conducted to the heat pipe and the heat transfer efficiency can be increased.

To accomplish the above object, the heat sink of the invention includes a fin set and a heat pipe. The fin set is composed of a plurality of fins and has an exposed area formed on one side thereof. The heat pipe penetrates through the fin set and the exposed area. A portion of the heat pipe is exposed and flattened in the exposed area. The exposed and flattened portion is used for connecting a heat generating device as a thermal junction surface.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a conventional heat sink;

FIG. 2 shows another conventional heat sink;

FIG. 3 is an exploded view of the first embodiment of the invention;

FIG. 4 is a schematic view of the invention and an electronic component;

FIG. 5 is a side plan view of FIG. 4;

FIG. 6 is a side plan view of the second embodiment of the invention; and

FIG. 7 is a side plan view of the third embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Please refer to FIGS. 3 and 4. The heat sink of the invention includes a fin set 3 and at least one heat pipe 4.

The fin set 3 is composed of a plurality of fins. These fins are of two types: the first type fins 31 and the second type fins 32. All of the fins 31, 32 are spaced combined by spacers 33, 34. The second type fins 32 are smaller than the first type fins 31 in size and a group of the second type fins 32 are sandwiched by two groups of the first type fins 31. Therefore, an exposed area 30 may be formed on one side of the fin set 3.

The first type fins 31 are provided with at least one circular hole 311 for being penetrated by the heat pipe 4. The second type fins 32 are provided with at least one semicircular hole 321 for being penetrated by the heat pipe 4. The semicircular hole 321 is formed by the shortened fin size. Thus the exposed area 30 is formed. Preferably, the circular hole 311 or semicircular hole 321 may be provided with a surrounding wall 312, 322 for increasing thermo-conductivity between the heat pipe 4 and the fin set 3.

FIGS. 4 and 5 show the heat sink of the invention and an electronic component 5 to be mounted thereby. As can be seen in FIG. 4, the exposed area 30 exposes a portion of the heat pipe 4. And the portion of the heat pipe 4, which is exposed, is flattened to be a flat thermojunction plane 40. Furthermore, if a plurality of heat pipes 4 are disposed, then the flattened portions of the heat pipes 4 are coplanar. The exposed area 30 is sized to fit the electronic component 5 to be mounted, i.e. the exposed area 30 is slightly larger than the electronic component 5 in size. Therefore, the heat sink can be directly mounted on the electronic component 5 by attaching the exposed portion of the thermo-junction plane 40 onto the electronic component 5. The heat generated by the electronic component 5 can be directly conducted to the heat pipe 4 without any other intermediates.

Please refer to FIG. 6, which shows the second embodiment of the invention. The second embodiment differs from the first embodiment by protruding the exposed area 30′. As shown, the exposed portion of the heat pipe 4′ is bent outwards so that the flat thermojunction plane 40′ slightly protrudes from the fin set 3′.

Please refer to FIG. 7, which shows the third embodiment of the invention. The third embodiment differs from the first embodiment by extending length of the flattened portion of the heat pipe 4″. That is, the flattened portion of the heat pipe 4″ extends towards two ends of the exposed area 30″. As shown, all the fins 31″, 32″ do not protrude from the flat thermo-junction plane 40″ so that the flat thermo-junction plane 40″ is coplanar to one side of the fin set 3″.

Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the spirit and the scope of the present invention. Accordingly, the foregoing description is by way of example only and is not intended to be limiting. The present invention is limited only as defined in the following claims and the equivalents thereto.

Claims

1. A heat sink comprising:

a fin set composed of a plurality of fins, having an exposed area formed on one side thereof; and

at least one heat pipe, penetrating through the fin set and the exposed area, wherein a portion of the at least one heat pipe is exposed and flattened in the exposed area for directly attaching an electronic component to be mounted.

2. The heat sink of claim 1, wherein the at least one heat pipe is two or more in number, and the flattened portions of the heat pipes are coplanar.

3. The heat sink of claim 1, wherein the fins are of two types, the first type fins are separately provided with circular holes for being passed through by the at least one heat pipe, the second type fins are separately provided with semicircular holes for accommodating the at least one heat pipe, and the exposed portion of the at least one heat pipe is formed by the second type fins.

4. The heat sink of claim 3, wherein the second type fins are sandwiched between two groups of the first type fins.

5. The heat pipe of claim 3, wherein each of the circular holes and the semicircular holes is provided with a circular surrounding wall and a semicircular wall, respectively.

6. The heat sink of claim 1, wherein the exposed area is dented to form a recess in the fin set.

7. The heat sink of claim 1, wherein the exposed area is protrudent from the fin set.

8. The heat sink of claim 1, wherein the exposed area occupies a whole side of the fin set.