Heat sink

• US 5,390,734 A
• Filed: 05/28/1993
• Issued: 02/21/1995
• Est. Priority Date: 05/28/1993
• Status: Expired due to Term

• Current Assignee: Lytron, Inc. (LTI Flexible Products Inc.)
• Original Assignee: Lytron, Inc. (LTI Flexible Products Inc.)
• Inventors: Goldman, Richard D., Voorhes, David W., Lopez, Robert R.
• Primary Examiner(s): Hepperle, Stephen M.
• Application Number:
  US08/070,088
• Time in Patent Office: 634 Days
• Field of Search: 165/185, 165/80.3, 174/16.3, 361/690, 361/699, 361/704
• US Class Current: 165/185
• CPC Class Codes: F28F 13/00 Arrangements for modifying heat-transfer, e.g. increasing, decreasing F28F1/00 - F28F11/00 take precedence
• CPC Class Codes: H01L 23/3677 Wire-like or pin-like cooling fins or heat sinks
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H05K 7/20445 the coupling element being an additional piece, e.g. thermal standoff

Abstract

A heat sink is provided having a bundle of thermally conductive fibers that extend from a heat receiving end to a heat dissipating end where they are splayed as extremely numerous fins of one or plural coalesced fibers to enlarge the effective heat convecting area. The splayed fins are supported or maintained in a splayed array by a structure. Heat dissipation capability is augmented by forcing a cooling fluid such as air through the splayed fins. The fins are initially caused to separate or splay by various techniques including electrostatic spreading, layering, tape rolling, selective coating removal, and elastic rebound, and are maintained in the splayed position by a frame, adhesion, or elastomers.

Claims

1. A heat sink, comprising:

a fiber bundle expanded in a cooling region into a plurality of separate fins of one or more fibers each;

said fiber bundle including a plurality of thermally conductive fibers extending from a first fiber bundle end to a second expanded fiber bundle end forming said plurality of fins;

the fins at said second expanded fiber bundle end being spaced apart from adjacent ones of said fins in a splayed pattern; and

means for maintaining said plurality of fins in said splayed pattern, said means for maintaining being independent of said fins.

2. The heat sink of claim 1, wherein said fibers are graphite.

3. The heat sink of claim 1, wherein said fibers are aluminum.

4. The heat sink of claim 1, wherein said fibers are copper.

5. The heat sink of claim 1, wherein a portion of said first fiber bundle end is metal impregnated.

6. The heat sink of claim 5, wherein said metal includes aluminum.

7. The heat sink of claim 5, wherein said metal includes copper.

8. The heat sink of claim 1, wherein said fins have a circular cross-section.

9. The heat sink of claim 1, wherein said fins have an oval cross-section.

10. The heat sink of claim 1, wherein said fins have a rectangular cross-section.

11. The heat sink of claim 1, wherein said fins are flat.

12. The heat sink of claim 1, wherein a portion of said fiber bundle is compressed sufficiently to minimize air within said fiber bundle.

13. A heat sink, comprising:

a fiber bundle expanded in a cooling region into a plurality of separate fins of one or more fibers each and having a heat dissipation surface area in said cooling region that includes the total area of all fins;

said fiber bundle including a plurality of thermally conductive fibers extending from a first fiber bundle end to a second expanded fiber bundle end forming said plurality of fins;

the fins at said second expanded fiber bundle end being spaced apart from adjacent ones of said fins in a splayed pattern that freely admits a flow of an environmental fluid therebetween in said cooling region;

the fins thus splayed in the cooling region having a vast heat dissipation surface area; and

each said fin being parallel to an adjacent fin proximate said first fiber bundle end.

14. A heat sink, comprising:

a fiber bundle expanded in a cooling region into a plurality of separate fins of one or more fibers each and having a heat dissipation surface area in said cooling region that includes the total area of all fins;

said fiber bundle including a plurality of thermally conductive fibers extending from a first fiber bundle end to a second expanded fiber bundle end forming said plurality of fins;

the fins at said second expanded fiber bundle end being spaced apart from adjacent ones of said fins in a splayed pattern that freely admits a flow of an environmental fluid therebetween in said cooling region;

the fins thus splayed in the cooling region having a vast heat dissipation surface area; and

at least a portion of each said fiber proximate said first fiber bundle end separated from an adjacent fiber by a supplemental thermal conductor.

15. The heat sink of claim 14, wherein said supplemental thermal conductor is a metallic film.

16. The heat sink of claim 15, wherein said metallic film includes copper.

17. The heat sink of claim 14, wherein said supplemental thermal conductor includes a plurality of graphite fibers.

18. A heat sink, comprising:

a fiber bundle expanded in a cooling region into a plurality of separate fins of one or more fibers each and having a heat dissipation surface area in said cooling region that includes the total area of all fins;

said fiber bundle including a plurality of thermally conductive fibers extending from a first fiber bundle end to a second expanded fiber bundle end forming said plurality of fins;

the fins at said second expanded fiber bundle end being spaced apart from adjacent ones of said fins in a splayed pattern that freely admits a flow of an environmental fluid therebetween in said cooling region;

the fins thus splayed in the cooling region having a vast heat dissipation surface area; and

said fiber bundle being provided with an insulating layer.

19. A heat sink, comprising:

a fiber bundle expanded in a cooling region into a plurality of separate fins of one or more fibers each and having a heat dissipation surface area in said cooling region that includes the total area of all fins;

said fiber bundle including a plurality of thermally conductive fibers extending from a first fiber bundle end to a second expanded fiber bundle end forming said plurality of fins;

the fins at said second expanded fiber bundle end being spaced apart from adjacent ones of said fins in a splayed pattern that freely admits a flow of an environmental fluid therebetween in said cooling region;

the fins thus splayed in the cooling region having a vast heat dissipation surface area;

means for retaining each fin in spaced apart relation from an adjacent fin; and

said means for retaining including a plurality of strips separating said plurality of fins into layers.

20. The heat sink of claim 19, wherein each of said plurality of strips includes a plurality of depressions, each said depression positioning a single fin therein.

21. A heat sink, comprising:

a fiber bundle expanded in a cooling region into a plurality of separate fins of one or more fibers each and having a heat dissipation surface area in said cooling region that includes the total area of all fins;

said fiber bundle including a plurality of thermally conductive fibers extending from a first fiber bundle end to a second expanded fiber bundle end forming said plurality of fins;

the fins at said second expanded fiber bundle end being spaced apart from adjacent ones of said fins in a splayed pattern that freely admits a flow of an environmental fluid therebetween in said cooling region;

the fins thus splayed in the cooling region having a vast heat dissipation surface area;

means for retaining each fin in spaced apart relation from an adjacent fin; and

said means for retaining including an adhesive.

22. A heat sink, comprising:

a fiber bundle expanded in a cooling region into a plurality of separate fins of one or more fibers each and having a heat dissipation surface area in said cooling region that includes the total area of all fins;

said fiber bundle including a plurality of thermally conductive fibers extending from a first fiber bundle end to a second expanded fiber bundle end forming said plurality of fins;

the fins at said second expanded fiber bundle end being spaced apart from adjacent ones of said fins in a splayed pattern that freely admits a flow of an environmental fluid therebetween in said cooling region;

the fins thus splayed in the cooling region having a vast heat dissipation surface area;

means for retaining each fin in spaced apart relation from an adjacent fin; and

said means for retaining including an elastomer.

23. A heat sink, comprising:

a fiber bundle expanded in a cooling region into a plurality of separate fins of one or more fibers each and having a heat dissipation surface area in said cooling region that includes the total area of all fins;

said fiber bundle including a plurality of thermally conductive fibers extending from a first fiber bundle end to a second expanded fiber bundle end forming said plurality of fins;

the fins at said second expanded fiber bundle end being spaced apart from adjacent ones of said fins in a splayed pattern that freely admits a flow of an environmental fluid therebetween in said cooling region;

the fins thus splayed in the cooling region having a vast heat dissipation surface area;

means for retaining each fin in spaced apart relation from an adjacent fin; and

said means for retaining includes a plurality of pins.