US3676815A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermally sensitive controls for electric circuits
Assignee: Lear Corp EEDS and Interiors
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Filing: 1969-07-28
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Granted: 1972-07-11
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Expires: 1989-07-28
Abstract
Abstract A control for an electric circuit of the kind having switching means adjustable between circuit making and breaking relations and wherein the adjustment of the switching means is effected by a thermally sensitive force applying member acting on the switching means, the force exerted by the force applying member being substantially instantaneously variable in response to changes in its temperature to and from a predetermined critical temperature. The force applying member is dimensionally stable until it is heated to or cooled below its critical temperature whereupon it either expands or contracts suddenly and with the ability to do substantial work. The force applying member may either expand or contract in response to an increase in temperature depending upon the manner in which the member is formed.
Inventors
- 👤 Gideon A Du Rocher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 00:26
CPC Classifications
H; H01; H01H; H01H61/00; H01H61/01; H01H61/0107
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
107 words
Thermally sensitive control apparatus for an electric circuit comprising switching means adjustable from conductive condition to non-conductive condition and vice versa; thermally sensitive self-restoring force applying means acting on said switching means and responsive to a change in temperature to and from a predetermined temperature to change dimensions, thereby to vary the force exerted on said switching means and effect adjustment of said switching means from one of said conditions to the other, and return, said force applying means being substantially stable dimensionally at ambient temperatures below said predetermined temperature; and means for varying the temperature of said force applying means to and from saId predetermined temperature.
Claim 2
Dependent Claim
107 words
Thermally sensitive control apparatus for an electric circuit comprising switching means adjustable from conductive condition to non-conductive condition and vice versa; thermally sensitive self-restoring force applying means acting on said switching means and responsive to a change in temperature to and from a predetermined temperature to change dimensions, thereby to vary the force exerted on said switching means and effect adjustment of said switching means from one of said conditions to the other, and return, said force applying means being substantially stable dimensionally at ambient temperatures below said predetermined temperature; and means for varying the temperature of said force applying means to and from saId predetermined temperature.
Claim 3
Dependent Claim
17 words
The apparatus set forth in claim 1 wherein the normal condition of said switching means is non-conductive.
Claim 4
Dependent Claim
21 words
The apparatus set forth in claim 1 including yieldable biasing means for yieldably maintaining said switching means in said non-conductive condition.
Claim 5
Dependent Claim
30 words
The apparatus set forth in claim 3 wherein said biasing means is operable yieldably to bias said contact means toward said conductive condition following adjustment thereof from said non-conductive condition.
Claim 6
Dependent Claim
24 words
The apparatus set forth in claim 1 wherein said force applying means expands in response to an increase in temperature to said predetermined temperature.
Claim 7
Dependent Claim
24 words
The apparatus set forth in claim 5 wherein said force applying means contracts in response to a decrease in temperature from said predetermined temperature.
Claim 8
Dependent Claim
24 words
The apparatus set forth in claim 1 wherein said force applying means contracts in response to an increase in temperature to said predetermined temperature.
Claim 9
Dependent Claim
24 words
The apparatus set forth in claim 7 wherein said force applying means expands in response to a decrease in temperature from said predetermined temperature.
Claim 10
Dependent Claim
15 words
The apparatus set forth in claim 1 wherein said force applying means is electrically conductive.
Claim 11
Dependent Claim
32 words
The apparatus set forth in claim 9 wherein the means for changing the temperature of said force applying means comprises an electric circuit of which said force applying means is a part.
Claim 12
Dependent Claim
25 words
The apparatus set forth in claim 10 including means for electrically bypassing said force applying means when said switching means is in said conductive condition.
Claim 13
Dependent Claim
21 words
The apparatus set forth in claim 1 wherein said force applying means comprises an electrical conductor formed by a tensile process.
Claim 14
Dependent Claim
14 words
The apparatus set forth in claim 12 wherein said conductor is formed of nitinol.
Claim 15
Dependent Claim
21 words
The apparatus set forth in claim 1 wherein said force applying means comprises an electrical conductor formed by a compression process.
Claim 16
Dependent Claim
14 words
The apparatus set forth in claim 14 wherein said conductor is formed of nitinol.
Claim 17
Dependent Claim
31 words
The apparatus set forth in claim 1 wherein said switching means comprises first and second contacts at least one of which is movable into and out of engagement with the other.
Claim 18
Dependent Claim
43 words
The apparatus set forth in claim 1 including spring means interposed between said force applying means and said switching means and exerting a force on said force applying means in one condition of said switching means tending to elongate said force applying means.
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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) | 1975-07-11 | 1976-01-10 | 1976-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-11 | 1980-01-10 | 1980-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-11 | 1984-01-10 | 1984-07-11 | $7700.00 | Window Closed / Lapsed |