US4054901A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Index mounting unitary heat sink apparatus with apertured base
Assignee: Thermalloy Inc
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Filing: 1975-10-14
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Granted: 1977-10-18
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Expires: 1995-10-14
Abstract
Abstract Disclosed is a unitary heat sink apparatus in the form of a U-shaped body of thermally conductive material adapted for use in connection with semiconductor device packages having a thermally conductive transfer plate adjacent one major face of the device package. Typical of such device packages is the TO-220 plastic power package. One leg of the U-shaped clip urges the thermal transfer plate into intimate contact with a flat portion of the opposite leg by the spring action provided by the base of the U. An aperture in the base of the U allows the leads to extend from the heat sink. Fins are included on one leg of the heat sink and means for attaching the heat sink apparatus to printed circuit boards are also disclosed.
Inventors
- 👤 Steven F. Edwards
- 👤 James A. Johnson
- 👤 William D. Jordan
- 👤 James D. Pritchett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:39
CPC Classifications
H; H10; H10W; H10W40/00; H10W40/60; H10W40/641
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
134 words
Unitary heat sink apparatus comprising a substantially U-shaped body of thermally conductive material, one leg of said U-shaped body providing a relatively broad area flat surface adapted to mate with the thermal transfer plate of a semiconductor encapsulation device and including indexing means protruding from said flat surface of said one leg for mating with indexing means provided in said encapsulation device, the opposite leg of said U-shaped body providing means for urging the thermal transfer plate of said encapsulation device into intimate contact with said one leg, and the base of said U-shaped body providing spring means for urging said opposite leg of said U-shaped body toward said one leg of said U-shaped body, said base further having an aperture therein for permitting the leads extending from said encapsulation device to extend therethrough.
Claim 2
Dependent Claim
134 words
Unitary heat sink apparatus comprising a substantially U-shaped body of thermally conductive material, one leg of said U-shaped body providing a relatively broad area flat surface adapted to mate with the thermal transfer plate of a semiconductor encapsulation device and including indexing means protruding from said flat surface of said one leg for mating with indexing means provided in said encapsulation device, the opposite leg of said U-shaped body providing means for urging the thermal transfer plate of said encapsulation device into intimate contact with said one leg, and the base of said U-shaped body providing spring means for urging said opposite leg of said U-shaped body toward said one leg of said U-shaped body, said base further having an aperture therein for permitting the leads extending from said encapsulation device to extend therethrough.
Claim 3
Dependent Claim
33 words
Apparatus as defined in claim 2 wherein said indexing means on said flat surface is a raised dimple adapted to mate with a hole in the heat transfer plate of said encapsulation device.
Claim 4
Dependent Claim
24 words
Apparatus as defined in claim 1 wherein said one leg is wider than said opposite leg and includes fins extending from the edges thereof.
Claim 5
Dependent Claim
22 words
Apparatus as defined in claim 3 wherein said fins extend in a direction substantially normal to the plane of said flat surface.
Claim 6
Dependent Claim
28 words
Apparatus as defined in claim 1 including a first tab extending from said one leg substantially in the plane of said flat surface and extending past said base.
Claim 7
Dependent Claim
63 words
Apparatus as defined in claim 4 including a first tab extending from said one leg substantially in the plane of said flat surface and extending past said base, and further including fins extending from the edges of said one leg at the end thereof nearest said base and including a tab extending from each of such fins and parallel with said first tab.
Claim 8
Dependent Claim
20 words
Apparatus as defined in claim 1 including parallel ridges in said one leg defining the edges of said flat surface.
Claim 9
Dependent Claim
70 words
Apparatus as defined in claim 1 including parallel ridges in said first leg defining the lateral edges of said flat surface, and having parallel notches in said flat surface between and parallel with said ridges, said notches extending from the end of said one leg opposite said base toward said base, and wherein said indexing means is a raised dimple on the portion of said flat surface between said notches.
Claim 10
Dependent Claim
38 words
Apparatus as defined in claim 1 wherein said means for urging the thermal transfer plate of an encapsulation device into intimate contact with said one leg is a tab extending from said opposite leg toward said one leg.
Claim 11
Dependent Claim
151 words
The combination comprising: a. a semiconductor encapsulation package including a plastic body having leads extending from one end thereof and a thermal transfer plate adjacent and forming one major face of said body and having indexing means in said thermal transfer plate, and b. a unitary heat sink comprising a substantially U-shaped body of thermally conductive material, the inner surface of one leg of said U-shaped body mating with said thermal transfer plate and including indexing means protruding from said inner surface of said one leg and mating with said indexing means in said thermal transfer plate, the opposite leg of said U-shaped body providing means for urging said thermal transfer plate into intimate contact with said one leg; the base of said U-shaped body providing spring means for urging said opposite leg toward said one leg, said base further having an aperture therein; and said leads extending through said aperture.
Claim 12
Dependent Claim
151 words
The combination comprising: a. a semiconductor encapsulation package including a plastic body having leads extending from one end thereof and a thermal transfer plate adjacent and forming one major face of said body and having indexing means in said thermal transfer plate, and b. a unitary heat sink comprising a substantially U-shaped body of thermally conductive material, the inner surface of one leg of said U-shaped body mating with said thermal transfer plate and including indexing means protruding from said inner surface of said one leg and mating with said indexing means in said thermal transfer plate, the opposite leg of said U-shaped body providing means for urging said thermal transfer plate into intimate contact with said one leg; the base of said U-shaped body providing spring means for urging said opposite leg toward said one leg, said base further having an aperture therein; and said leads extending through said aperture.
Claim 13
Dependent Claim
24 words
The combination defined in claim 10 wherein said one leg is wider than said opposite leg and includes fins extending from the edges thereof.
Claim 14
Dependent Claim
19 words
The combination defined in claim 11 wherein said fins extend in a direction substantially normal to said first leg.
Claim 15
Dependent Claim
28 words
The combination defined in claim 10 including a first tab extending from said one leg substantially in the plane of said first leg and extending beyond said base.
Claim 16
Dependent Claim
56 words
The combination defined in claim 12 including a first tab extending from said one leg substantially in the plane of said one leg and extending parallel with said leads, and further including a fin tab extending from each of said fins nearest the base, said fin tabs extending beyond said base and parallel with said leads.
Claim 17
Dependent Claim
26 words
The combination defined in claim 10 including parallel ridges on the inner face of said one leg parallel with the edges of said thermal transfer plate.
Claim 18
Dependent Claim
41 words
The combination defined in claim 10 wherein the base of said U-shaped body is substantially wider than the thickness of said plastic body, and including flap means depending from said opposite leg for urging said plastic body toward said first leg.
Claim 19
Dependent Claim
20 words
The combination defined in claim 16 wherein said one leg and said opposite leg are of substantially the same width.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-10-17 | 1981-04-18 | 1981-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-17 | 1985-04-18 | 1985-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-17 | 1989-04-18 | 1989-10-18 | $7700.00 | Window Closed / Lapsed |