Self clamping heat sink

• US 5,381,041 A
• Filed: 04/05/1994
• Issued: 01/10/1995
• Est. Priority Date: 04/05/1994
• Status: Expired due to Fees

• Current Assignee: Wakefield Thermal Solutions, Inc. (The Heico Cos. LLC)
• Original Assignee: Wakefield Engineering, Inc.
• Inventors: Harmon, Ronald A.
• Primary Examiner(s): Jackson, Jerome
• Assistant Examiner(s): Kelley, Nathan K.
• Application Number:
  US08/222,843
• Time in Patent Office: 280 Days
• Field of Search: 257/718, 257/727, 257/675, 257/706, 165/80.2, 165/80.3
• US Class Current: 257/718
• 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

Abstract

A self clamping heat sink for releasable connection to an electrical component having a bottom surface and a top surface. The self clamping heat sink includes a base and a pair of inverted U-shaped spring arms at opposite sides of the base which extend upwardly from the base. A clamping finger extends inwardly from the outer leg portion of each spring arm to a free end which overlies the base. The free ends of the spring arms are raised to an upper position relative the base by applying external force to squeeze the outer leg portions of the spring arm toward each other. This enables an electrical component to be placed on the base and below the free ends of the clamping fingers. When external force is removed from the spring arms, the clamping fingers try to return to their normal lower position and engage the top surface of the electrical component so that the electrical component is clamped between the base and the fingers.

Claims

1. A self clamping heat sink for releasable connection to an electrical component having a bottom surface and a top surface, said self clamping heat sink comprising:

(a) a base having an upper horizontal surface;

(b) a cantilevered spring arm which is fixed to said base and which is located above and out of vertical alignment with the upper surface of said base, said spring arm normally occupying a clamping position relative to said base and being resiliently bendable to a non-clamping position toward the base upon the application of a predetermined external force to said spring arm; and

(c) a cantilevered clamping finger which is fixed to said spring arm and which extends toward said base said clamping finger having a free end which is vertically aligned with and spaced from the upper surface of said base so that when said spring arm is moved from said clamping position to said non-clamping position, the free end of said clamping finger is moved away from the upper surface of said base for enabling the free end of said clamping finger to be spaced from the upper surface of an electrical component which is placed on the upper surface of said base to enable said electrical component to be removed from and applied to the upper surface of said base, the free end of said clamping finger engaging the upper surface of said electrical component with spring pressure in the absence of said predetermined force due to the spring bias of said spring arm toward its clamping position.

2. A self clamping heat sink as recited in claim 1, wherein said spring arm is a first spring arm and said clamping finger is a first clamping finger, said self clamping heat sink further comprising a second spring arm which is identical to said first spring arm and a second clamping finger which is identical to said first clamping finger, said first spring arm being fixed to a first side of said base, said second spring arm being fixed to a second side of said base which is opposite said first side, said first clamping finger extending from said first spring arm toward said second side, said second clamping finger extending from said second spring arm toward said first side.

3. A self clamping heat sink as recited in claim 2, wherein said first and second clamping fingers are horizontally aligned and the free ends of said first and second clamping fingers are spaced from one another.

4. A self clamping heat sink as recited in claim 1, wherein said spring arm comprises:

(a) an inner leg portion which is fixed to said base and which extends upwardly from said base; and

(b) an outer leg portion which is fixed to said inner leg portion at a connecting point above said base and which extends downwardly from said connecting point, said clamping finger being fixed to said outer leg portion and extending toward said inner leg portion.

5. A self clamping heat sink as recited in claim 1, wherein the free end of said clamping finger has a convex lower surface for engaging the top surface of said electrical component.

6. A self clamping heat sink for releasable connection to an electrical component having a bottom surface and a top surface, said self clamping heat sink comprising:

(a) a base having an upper horizontal surface, a first side and a second side which is opposite said first side;

(b) an inverted U-shaped spring arm which has an inner leg portion which is fixed to said first side and which extends upwardly from said first side and an outer leg portion which is spaced from said inner leg portion and which extends downwardly from said inner leg portion to a free end, said outer leg portion being out of vertical alignment with the upper surface of said base and normally occupying a clamping position and being resiliently bendable toward said inner leg portion and said base to a non-clamping position upon application of a predetermined external force to said outer leg portion in the direction of said inner leg portion;

(c) a cantilevered clamping finger which is fixed to said outer leg portion and which extends toward said base, said clamping finger having a free end which is vertically aligned with the upper surface of said base and which is positioned above the upper surface of said base so that when said outer leg portion is in said non-clamping position, the free end of said clamping finger is spaced from the top surface of an electrical component which is placed on the upper surface of said base to enable said electrical component to be removed from and applied to the upper surface of said base, the free end of said clamping finger engaging the top surface of said electrical component with spring pressure in the absence of said predetermined external force to said outer leg portion due to the spring bias of said outer leg toward its clamping position.

7. A self clamping heat sink for releasable connection to an electrical component having a bottom surface and a top surface, said self clamping heat sink comprising:

(a) a base having an upper horizontal surface, a first side and a second side which is opposite said first side;

(b) a first inverted U-shaped spring arm which has a vertical inner leg portion which is fixed to the first side of said base, and a vertical outer leg portion which is spaced from said inner leg portion and which terminates in a free end, said outer end portion being resiliently bendable toward said inner leg portion;

(c) a first cantilevered clamping finger which is fixed to the outer leg of said first spring arm and which extends toward said base, said first clamping finger having a free end which bears down with biasing pressure from said outer leg portion on the top surface of an electrical component which rests on the upper surface of said base;

(d) a second inverted U-shaped spring arm which has a vertical inner leg portion which is fixed to the second side of said base, and a vertical outer leg portion which is spaced from the inner leg portion of said second spring arm and which terminates in a free end, the outer end portion of said second spring arm being resiliently bendable toward the inner leg portion of said second spring arm; and

(e) a second cantilevered clamping finger which is fixed to the outer leg of said second spring arm and which extends toward said base, said second clamping finger having a free end which bears down with biasing pressure from the outer leg portion of said second spring arm on the upper surface of said electrical component, the free ends of said first and second clamping finger moving to a position above the top surface of said electrical component upon application of an external force to said outer leg portions to bend said outer leg portions of said first and second spring arm toward each other to enable said electrical component to be removed from and applied to the upper surface of said base, said first and second clamping fingers engaging the top surface of said electrical component upon removal of said external force to said outer leg portions.

8. A self clamping heat sink for releasable connection to an electrical component having a bottom surface and a top surface, said self clamping heat sink comprising:

(a) a base having an upper horizontal surface, a first side and a second side which is opposite said first side;

(b) a first inverted U-shaped spring arm which has a first inner leg portion which is fixed to said first side and which extends upwardly from said first side and a first outer leg portion which is spaced from said first inner leg portion and which extends downwardly from said first inner leg portion to a free end, said first outer leg portion normally occupying a clamping position and being resiliently bendable toward said first inner leg portion to a non-clamping position upon application of a predetermined external force to said first outer leg portion in the direction of said first inner leg portion;

(c) a cantilevered first clamping finger which is fixed to said first outer leg portion and which extends toward said base, said first clamping finger having a free end which is vertically aligned with the upper surface of said base and which is positioned above the upper surface of said base so that when said first outer leg portion is in said non-clamping position, the free end of said first clamping finger is spaced from the top surface of an electrical component which is placed on the upper surface of said base to enable said electrical component to be removed from and applied to the upper surface of said base, the free end of said first clamping finger engaging the top surface of said electrical component with spring pressure in the absence of said predetermined external force to said outer leg portion due to the spring bias of said first outer leg toward its clamping position;

(d) a second inverted U-shaped spring arm which has a second inner leg portion which is fixed to said second side and which extends upwardly from said second side and a second outer leg portion which is spaced from said second inner leg portion and which extends downwardly from said second inner leg portion to a free end, said second outer leg portion normally occupying a clamping position and being resiliently bendable toward said second inner leg portion to a non-clamping position upon application of a predetermined external force to said second outer leg portion in the direction of said second inner leg portion;

(e) a cantilevered second clamping finger which is fixed to said second outer leg portion and which extends toward said base, said second clamping finger having a free end which is vertically aligned with the upper surface of said base and which is positioned above the upper surface of said base so that when said second outer leg portion is in said non-clamping position, the free end of said second clamping finger is spaced from the top surface of an electrical component which is placed on the upper surface of said base to enable said electrical component to be removed from and applied to the upper surface of said base, the free end of said second clamping finger engaging the top surface of said electrical component with spring pressure in the absence of said predetermined external force to said second outer leg portion due to the spring bias of said second outer leg toward its clamping position, said first and second outer leg portions being horizontally opposed so that said first and second outer leg portions can be moved simultaneously to their respective non-clamping positions by grasping said clamping heat sink by said first and second outer leg portions and squeezing said first and second outer leg portions toward one another.

9. A self-clamping heat sink as recited in claim 8, wherein said first and second clamping fingers are horizontally aligned and the free ends of said first and second clamping fingers are spaced from one another.

10. A self-clamping heat sink for releasable connection to an electrical component having a bottom surface and a top surface, said self clamping heat sink comprising;

(a) a base having an upper horizontal surface, a first side and a second side which is opposite said first side;

(b) an inverted U-shaped spring arm which has an inner leg portion which is fixed to said first side and which extends upwardly from said first side and an outer leg portion which is spaced from said inner leg portion and which extends downwardly from said inner leg portion to a free end, said outer leg potion normally occupying a clamping position and being resiliently bendable toward said inner leg portion to a non-clamping position upon application of a predetermined external force to said outer leg potion in the direction of said inner leg portion, said inner leg portion having an aperture;

(c) a cantilevered clamping finger which is fixed to said outer leg portion and which extends through the aperture in said inner leg portion toward said base, said clamping finger having a free end which is vertically aligned with the upper surface of said base and which is positioned above the upper surface of said base so that when said outer leg portion is in said non-clamping position, the free end of said clamping finger is spaced from the top surface of an electrical component which is placed on the upper surface of said base to enable said electrical component to be removed from and applied to the upper surface of said base, the free end of said clamping finger engaging the top surface of said electrical component with spring pressure in the absence of said predetermined external force to said outer leg portion due to the spring bias of said outer leg toward its clamping position.

11. A self-clamping heat sink as recited in claim 10, wherein said clamping finger is an integral part of said outer leg portion, said clamping finger being formed from material from said outer leg portion and bent through said aperture toward said base.