US4078187A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Piezoelectric switching device
Assignee: Oki Electric Industry Co Ltd
•
Filing: 1976-08-18
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Granted: 1978-03-07
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Expires: 1996-08-18
Abstract
Abstract A contactless switching device in which a mechanical displacement is converted into an electric signal by a piezoelectric element so that make and break of the circuit is effected by this electric signal.
Inventors
- 👤 Hajime Kanisawa
- 👤 Korzi Tanagawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:52
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/94; H03K17/96; H03K17/964
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
79 words
A contactless switching device comprising an operating key, a piezo-electric element for converting the mechanical displacement made by said operating key into an electric signal, a complementary MOS integrated circuit for shaping and amplifying the electric signal generated from said piezo-electric element, a permanent magnet arranged movable along with said operating key, and a floating permanent magnet arranged movable in response to the first-said permanent magnet and adapted to impinge against said piezo-electric element to generate said electric signal.
Claim 2
Dependent Claim
79 words
A contactless switching device comprising an operating key, a piezo-electric element for converting the mechanical displacement made by said operating key into an electric signal, a complementary MOS integrated circuit for shaping and amplifying the electric signal generated from said piezo-electric element, a permanent magnet arranged movable along with said operating key, and a floating permanent magnet arranged movable in response to the first-said permanent magnet and adapted to impinge against said piezo-electric element to generate said electric signal.
Claim 3
Dependent Claim
52 words
A contactless switching device claimed in claim 1, wherein said piezo-electric element is disposed at an upper part while said floating permanent magnet is disposed at a lower part, and wherein said floating permanent magnet is arranged to jump up in response to said permanent magnet to impinge against said piezo-electric element.
Claim 4
Dependent Claim
28 words
A contactless switching device claimed in claim 1, wherein said permanent magnet is ring-shaped and said floating permanent magnet is disposed within the ring of said permanent magnet.
References Cited (Backward Citations)
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US3586888A
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US3725908A
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US3898534A
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US3935485A
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US4015151A
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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) | 1981-03-06 | 1981-09-05 | 1982-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-03-06 | 1985-09-05 | 1986-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-03-06 | 1989-09-05 | 1990-03-07 | $7700.00 | Window Closed / Lapsed |