Spring clip and heat sink assembly for electronic components

• US 5,436,798 A
• Filed: 01/21/1994
• Issued: 07/25/1995
• Est. Priority Date: 01/21/1994
• Status: Expired due to Fees

• Current Assignee: Wakefield Thermal Solutions, Inc. (The Heico Cos. LLC)
• Original Assignee: Wakefield Engineering, Inc.
• Inventors: Wieland, Howard N. Jr.
• Primary Examiner(s): Thompson, Gregory D.
• Application Number:
  US08/184,945
• Time in Patent Office: 550 Days
• Field of Search: 174/16.3, 165/80.2, 165/80.3, 165/185, 257/718-719, 257/726-727, 361/704, 361/707, 361/709-711, 361/717-718, 361/722
• US Class Current: 361/710
• CPC Class Codes: H01L 23/4093 Snap-on arrangements, e.g. clips
• 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 7/1084 pin grid array package carriers

Abstract

A spring clip for clamping a heat sink module which has a plurality of upwardly extending cooling elements to an electronic module. The spring clip includes a horizontal grid like foot portion which engages the upper surface of the heat sink module a vertical leg portion which extends along the side of the heat sink module and the electronic module and a bendable and resilient connecting portion which extends from the inner end of the foot portion to the upper end of the leg portion. The electronic module has a first latching element at its side surface for engaging a complementary second latching element which forms part of the vertical leg portion of the spring clip. The spring clip is rendered from a non-clamping position in which the latching element of the clip is above the latching element of the electronic module to a clamping position by bending the connecting portion downwardly from its inner end to lower the vertical leg portion so that the first and second latching elements are engaged.

Claims

1. A spring clip having a non-clamping position and a clamping position for clamping a heat sink module to an electronic component, so that the heat sink module is between the spring clip and the electronic component, said spring clip comprising:

(a) a horizontal foot portion which has an inner end and an outer end, said foot portion having a plurality of spaced ribs for engaging the upper surface of a heat sink module;

(b) a vertical leg portion having an upper end which is higher than said foot portion and a lower end which is lower than said foot portion, said leg portion being a flat strip of sheet metal having a broad side surface which faces said foot portion, the lower end of said leg portion having an outer inverted U-shaped cut, an outer projection which has an upwardly facing free end edge being formed from the portion of said leg portion which lies within said cut and which is bent along a horizontal line at the bottom of said cut so that said outer projection extends at an angle away from said foot portion, said leg portion having an inner inverted U-shaped cut within the area of said outer projection, an inner projection which has an upwardly facing free end edge being formed from the portion of said outer projection which lies within said inner cut, said inner projection being bent along a horizontal line at the bottom of said inner cut so that said inner projection extends at an angle toward said foot portion; and

(c) a bendable and resilient connecting portion which has an inner end which is fixed to said foot portion and an outer end which is fixed to the upper end of said leg portion so that said leg portion is spaced from the outer end of said foot portion, said spring clip being normally in its non-clamping position, said spring clip being rendered to its said clamping position upon application of downward pressure to said leg portion so as to cause said connecting portion to bend downwardly from the inner end of said connecting portion and to lower said leg portion relative to said foot portion for enabling said outer projection to engage a downwardly facing surface of an electronic component to which said spring clip is applied.

2. A spring clip having a non-clamping position and a clamping position for clamping a heat sink module to an electronic component, so that the heat sink module is between the spring clip and the electronic component, said spring clip comprising:

(a) a horizontal foot portion which has an inner end and an outer end, said foot portion having a plurality of spaced ribs for engaging the upper surface of a heat sink module;

(b) a vertical leg portion having an upper end which is higher than said foot portion and a lower end which is lower than said foot portion, the lower end of said vertical leg portion having a latching element for engaging a complementary latching element of an electronic component;

(c) a bendable and resilient connecting portion which has an inner end which is fixed to said foot portion and an outer end which is fixed to the upper end of said leg portion so that said leg portion is spaced from the outer end of said foot portion, said spring clip being normally in its non-clamping position, said spring clip being rendered to its clamping position upon application of downward pressure to said leg portion so as to cause said connecting portion to bend downwardly from the inner end of said connecting portion and to lower said leg portion relative to said foot portion for enabling said latching element to engage a complementary latching element of an electronic component to which said spring clip is applied; and

(d) a resilient finger which is fixed to said foot portion and which extends upwardly from said foot portion, said finger having a free upper end for engaging at least one of an upwardly extending cooling element of a heat sink to which said spring clip is applied to provide substantial resistance to the upward movement of said foot portion relative to the heat sink while providing minimal resistance to the downward movement of said foot portion relative to the heat sink.

3. A spring clip as recited in claim 2, wherein at least the upper portion of said finger is at an angle to the vertical.

4. A spring clip having a non-clamping position and a clamping position for clamping a heat sink module to an electronic component, so that the heat sink module is between the spring clip and the electronic component, said spring clip comprising:

(a) a horizontal foot portion which has an inner end and an outer end, said foot portion having a plurality of spaced ribs for engaging the upper surface of a heat sink module;

(b) a vertical leg portion having an upper end which is higher than said foot portion and a lower end which is lower than said foot portion, the lower end of said vertical leg portion having a latching element for engaging a complementary latching element of an electronic component;

(c) a bendable and resilient connecting portion which has an inner end which is fixed to said foot portion and an outer end which is fixed to the upper end of said leg portion so that said leg portion is spaced from the outer end of said foot portion, said spring clip being normally in its non-clamping position, said spring clip being rendered to its clamping position upon application of downward pressure to said leg portion so as to cause said connecting portion to bend downwardly from the inner end of said connecting portion and to lower said leg portion relative to said foot portion for enabling said latching element to engage a complementary latching element of an electronic component to which said spring clip is applied;

(d) a resilient first finger which is fixed to the inner end of said foot portion and which extends upwardly from said foot portion, said first finger having a free upper end for engaging at least one of an upwardly extending cooling element of a heat sink to which said spring clip is applied; and

(e) a resilient second finger which is fixed to the outer end of said foot portion and which extends upwardly from said foot portion, said second finger having a free upper end for engaging at least one of an upwardly extending cooling element of a heat sink, said first and second fingers providing substantial resistance to the upward movement of said foot portion relative to the heat sink while providing minimal resistance to the downward movement of said foot portion relative to the heat sink.

5. A spring clip as recited in claim 4;

wherein at least the upper end of each of said first and second fingers is at an angle to the vertical.

6. A spring clip as recited in claim 5;

wherein the upper ends of said first and second fingers extend away from each other.

7. A spring clip as recited in claim 6, wherein the upper end of said first finger extends upwardly at an angle toward said leg portion and the upper end of said second finger extends upwardly at an angle away from said leg portion.

8. A spring clip having a non-clamping position and a clamping position for clamping a heat sink module to an electronic component, so that the heat sink module is between the spring clip and the electronic component, said spring clip comprising:

(a) a horizontal foot portion which has an inner end and an outer end, said foot portion having a plurality of spaced ribs for engaging the upper surface of a heat sink module;

(b) a vertical leg portion having an upper end which is higher than said foot portion and a lower end which is lower than said foot portion, the lower end of said vertical leg portion having a latching element for engaging a complementary latching element of an electronic component;

(c) a bendable and resilient connecting portion which has an inner end which is fixed to said foot portion and an outer end which is fixed to the upper end of said leg portion so that said leg portion is spaced from the outer end of said foot portion, said spring clip being normally in its non-clamping position, said spring clip being rendered to its clamping position upon application of downward pressure to said leg portion so as to cause said connecting portion to bend downwardly from the inner end of said connecting portion and to lower said leg portion relative to said foot portion for enabling said latching element to engage a complementary latching element of an electronic component to which said spring clip is applied; and

(d) a substantially horizontal finger tab which is fixed to said leg portion, said finger tab extending outwardly away from said leg portion.

9. A spring clip having a non-clamping position and a clamping position for clamping a heat sink module to an electronic component, so that the heat sink module is between the spring clip and the electronic component, said spring clip comprising:

(a) a horizontal foot portion which has an inner end and an outer end, said foot portion having a plurality of spaced ribs for engaging the upper surface of a heat sink module;

(b) a vertical leg portion having an upper end which is higher than said foot portion and a lower end which is lower than said foot portion, the lower end of said vertical leg portion having a projection for engaging a downwardly facing surface of an electronic module, said leg portion being a flat strip of sheet metal having a broad side surface which faces said foot portion, said fiat strip having an inverted U-shaped cut, said projection being formed from the portion of said strip which lies within said cut and which is bent along a horizontal line at the bottom of said cut so that said projection extends at an angle toward said foot portion; and

(c) a bendable and resilient connecting portion which has an inner end which is fixed to said foot portion and an outer end which is fixed to the upper end of said leg portion so that said leg portion is spaced from the outer end of said foot portion, said spring clip being normally in its non-clamping position, said spring clip being rendered to its clamping position upon application of downward pressure to said leg portion so as to cause said connecting portion to bend downwardly from the inner end of said connecting portion and to lower said leg portion relative to said foot portion for enabling said projection to engage a downwardly facing surface of an electronic component to which said spring clip is applied.

10. A spring clip and heat sink assembly for application to an electronic component having a downwardly facing edge surface, said spring clip and heat sink assembly comprising:

(a) a heat sink module having a base which has a first end, a second end which is opposite and first end, an upper surface and a bottom surface for abutting the upper surface of an electronic component, said heat sink module having a plurality of spaced upwardly extending vertical cooling elements which are fixed to the upper surface of said heat sink module;

(b) a first spring clip having a non-clamping position and a clamping position for clamping the first end of said heat sink module to an electronic component, said first spring clip comprising;

(1) a horizontal first foot portion which has an inner end and an outer end, said first foot portion having a plurality of spaced ribs which extend between said vertical cooling elements, said ribs engaging the upper surface of said heat sink module;

(2) a vertical first leg portion having an upper end which is higher than said horizontal first foot portion and a lower end which is below said horizontal foot portion, said first leg portion having a first projection which extends away from said first foot portion, said first projection having a free end edge; and

(3) a bendable and resilient first connecting portion which is spaced from the upper surface of said base, said first connecting portion having an inner end which is fixed to said first foot portion and an outer end which is fixed to the upper end of said first leg portion so that said first leg portion is spaced from the outer end of said first foot portion, said spring clip being normally in its non-clamping position, said first spring clip being rendered to its clamping position upon application of downward pressure to said first leg portion so as to cause said first connecting portion to bend downwardly from the inner end of said first connecting portion and to lower said first leg portion relative to said foot portion for enabling the free end edge of said first projection to engage a downwardly facing surface of an electronic component to which said spring clip and heat sink assembly is applied; and

(c) a second spring clip having a non-clamping position and a clamping position for clamping the second end of said heat sink module to an electronic component, said second spring clip comprising;

(1) a horizontal second foot portion which has an inner end and an outer end, said second foot portion having a plurality of spaced ribs which extend between said vertical cooling elements, said ribs engaging the upper surface of said heat sink module;

(2) a vertical second leg portion having an upper end which is higher than said horizontal second foot portion and a lower end which is below said horizontal second foot portion, said second leg portion having a second projection which extends away from said second foot portion, said second projection having a free end edge; and

(3) a bendable and resilient second connecting portion which is spaced from the upper surface of said base, said second connecting portion having an inner end which is fixed to said second foot portion and an outer end which is fixed to the upper end of said second leg portion so that said second leg portion is spaced from the outer end of said second foot portion, said spring clip being normally in its non-clamping position, said second spring clip being rendered to its clamping position upon application of downward pressure to said second leg portion so as to cause said second connecting portion to bend downwardly from the inner end of said second connecting portion and to lower said second leg portion relative to said foot portion for enabling the free end edge of said first projection to engage a downwardly facing surface of an electronic component to which said spring clip and heat sink assembly is applied.

11. A spring clip and heat sink assembly as recited in claim 10, wherein each of said first and second projection extends upwardly at an acute angle to the vertical toward said heat sink module.

12. A spring clip and heat sink assembly as recited in claim 10, wherein each of said first and second spring clips is made of metal.

13. A spring clip and heat sink assembly as recited in claim 10, wherein each of said first and second spring clips further comprises a resilient finger which is fixed to the foot portion of the clip and which extends upwardly from the foot portion, each of said resilient fingers having a free upper end which engages at least one of said vertical cooling elements to provide substantial resistance to the upward movement of its corresponding spring clip relative to the upper surface of the base of said heat sink module while providing minimal resistance to the downward movement of said corresponding spring clip relative to said upper surface.

14. A spring clip and heat sink assembly as recited in claim 13, wherein at least the upper end of each of said fingers is at an angle to the vertical toward the vertical cooling element which is engaged by the finger.

15. A spring clip and heat sink assembly as recited in claim 10, wherein each of said spring clips further comprises:

(a) a resilient first finger which is fixed to the inner end of the foot portion of its corresponding spring clip and which extends upwardly from the foot portion of said corresponding spring clip, said first finger having a free upper end which engages at least one of said vertical cooling elements; and

(b) a resilient second finger which is fixed to the outer end of the foot portion of said corresponding spring clip and which extends upwardly from the foot portion of said corresponding spring clip, said second finger having a free upper end which engages at least one of said vertical cooling elements, said first and second fingers providing substantial resistance to the upward movement of said corresponding spring clip relative to the upper surface of said base while providing minimal resistance to the downward movement of said corresponding spring clip relative to the upper surface of said base.

16. A spring clip and heat sink assembly as recited in claim 15, wherein at least the upper end of each of said first and second fingers is at an angle to the vertical.

17. A spring clip and heat sink assembly as recited in claim 16, wherein the upper ends of the first and second fingers of each of said spring clips extend away from each other.

18. A spring clip and heat sink assembly as recited in claim 17, wherein the upper end of said first finger extends upwardly at an angle toward the portion of said corresponding spring clip and the upper end of said second finger extends upwardly at an angle away from the leg portion of said corresponding spring clip.

19. A spring clip and heat sink assembly as recited in claim 10, wherein each of said first and second spring clips further comprises a substantially horizontal finger tab which is fixed to the leg portion of its corresponding spring clip, said finger tab extending outwardly away from said heat sink module.

20. A spring clip and heat sink assembly as recited in claim 10, wherein the leg portion of each of said first and second spring clips has at least one aperture which is horizontally aligned with said vertical cooling elements.

21. A spring clip and heat sink assembly as recited in claim 10, wherein the inner end of the connecting portion of each of said first and second spring clips is fixed to the inner end of the foot portion of its respective spring clip, each of said connection portions having spaced ribs which extend between said vertical cooling elements so that said vertical cooling elements extend upwardly above said connecting portions.

22. A spring clip and heat sink assembly as recited in claim 10, wherein the projection for each of said first and second spring clips is an inner projection, each of said first and second spring clips further comprising an outer projection which is fixed to the foot portion of its respective spring clip and which extends away from said heat sink module, said inner and outer projections being located below said heat sink module, so that an applied downward pressure against each of said outer projections will cause the foot portion of its corresponding spring clip to move downwardly for disengaging the inner projection of its corresponding spring clip from a downwardly facing edge surface of an electronic component to which said spring clip and heat sink assembly is applied.

23. A spring clip and heat sink assembly as recited in claim 22, wherein said outer projection extends upwardly at an acute angle to the leg portion of its corresponding spring clip.

24. A spring clip having a non-clamping position and a clamping position for clamping a heat sink module to an electronic component so that the heat sink module is between the spring clip and the electronic component, said spring clip comprising:

(a) a horizontal foot portion which has a first component for engaging an upper surface of a heat sink module and a second component for frictionally engaging cooling elements which extend vertically from the upper surface of a heat sink module for holding the spring clip on the upper surface of a heat sink module;

(b) a vertical leg portion having an upper end which is higher than said foot portion and a lower end which is lower than said foot portion, the lower end of said vertical leg portion having a latching element for engaging a complementary latching element of an electronic component; and

(c) a bendable and resilient connecting portion which has an inner end which is fixed to said foot portion and an outer end which is fixed to the upper end of said leg portion so that said leg portion is spaced from said foot portion, said spring clip being normally in its non-clamping position, said spring clip being rendered to its clamping position upon application of downward pressure to said leg portion so as to cause said connecting portion to bend downwardly from the inner end of said connecting portion and to lower said leg portion relative to said foot portion for enabling said latching element to engage a complementary latching element of an electronic component to which said spring clip is applied.