US3760243A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Capacitive keyswitch
Assignee: General Electric Co
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Filing: 1972-09-21
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Granted: 1973-09-18
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Expires: 1992-09-21
Abstract
Abstract A variable capacitance keyswitch is disclosed in which a differential capacitor is formed by two fixed plates and a moveable plate therebetween. Each plate is in the shape of the frustum of a cone. Depression of the pushkey varies the capacitance between each fixed plate and the moveable plate over a range of about one order of magnitude, or greater. In addition, depression of the pushkey provides a push-pull capacitance variation between fixed and moveable plates, achieving an electrical snap action effect useful in typical bistable flipflop circuitry.
Inventors
- 👤 D Peroutky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:13
CPC Classifications
H; H01; H01G; H01G5/00; H01G5/04; H01G5/12
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
60 words
A variable capacitance keyswitch comprising: first and second fixed plates; a moveable plate; said fixed and moveable plates having a non-planar shape and nesting one in the other when the plates exhibit a high capacitance; and actuating means, mechanically coupled to said moveable plate, for differentially varying the capacitance between said moveable plate and said first and second fixed plates.
Claim 2
Dependent Claim
60 words
A variable capacitance keyswitch comprising: first and second fixed plates; a moveable plate; said fixed and moveable plates having a non-planar shape and nesting one in the other when the plates exhibit a high capacitance; and actuating means, mechanically coupled to said moveable plate, for differentially varying the capacitance between said moveable plate and said first and second fixed plates.
Claim 3
Dependent Claim
26 words
A variable capacitance keyswitch as set forth in claim 1 wherein said plates are in the shape of the surface of the frustum of a cone.
Claim 4
Dependent Claim
159 words
A variable capacitance keyswitch comprising: a first fixed plate; a second fixed plate; a moveable plate positioned between said first and second fixed plates; said first, second and moveable plate being in the shape of the frustum of a cone and capable of nesting one within the other; shaft means connected to said moveable plate for nesting said moveable plate with either of said first or second fixed plates; first and second electrical conductors connected to said first and second fixed plates respectively; base means having three apertures and having said first fixed plate attached thereto; cover means having the second fixed plate attached thereto and an aperture through which said shaft means moves; said base means and said cover means defining a volume in which said moveable plate moves; and electrically conductive resilient means connected to said moveable plate and connected to a third electrical conductor; said first, second and third electrical conductors passing through said three apertures.
Claim 5
Dependent Claim
159 words
A variable capacitance keyswitch comprising: a first fixed plate; a second fixed plate; a moveable plate positioned between said first and second fixed plates; said first, second and moveable plate being in the shape of the frustum of a cone and capable of nesting one within the other; shaft means connected to said moveable plate for nesting said moveable plate with either of said first or second fixed plates; first and second electrical conductors connected to said first and second fixed plates respectively; base means having three apertures and having said first fixed plate attached thereto; cover means having the second fixed plate attached thereto and an aperture through which said shaft means moves; said base means and said cover means defining a volume in which said moveable plate moves; and electrically conductive resilient means connected to said moveable plate and connected to a third electrical conductor; said first, second and third electrical conductors passing through said three apertures.
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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) | 1976-09-17 | 1977-03-19 | 1977-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-17 | 1981-03-19 | 1981-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-17 | 1985-03-19 | 1985-09-18 | $7700.00 | Window Closed / Lapsed |