US4455494A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electret device
Assignee: Toshiba Corp
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Filing: 1983-06-03
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Granted: 1984-06-19
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Expires: 2003-06-03
Abstract
Abstract An electret device having its electric charges introduced to a remote electrode. A conductive electrode is secured to one surface of a polarized dielectric body. A cover body made of conductive material is attached to the opposite surface of the dielectric body, and a remote electrode is connected through a conductive wire to the cover body.
Inventors
- 👤 Masamichi Tanaka
- 👤 Hiroto Wada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 09:39
CPC Classifications
H; H01; H01G; H01G7/00; H01G7/02
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
78 words
An electret device comprising: a dielectric body provided with electric charges, a conductive electrode secured on one surface of said dielectric body, a cover body comprised of a conductive material and attached on the opposite surface of said dielectric body, and a remote electrode electrically connected to said cover body through a conductive wire, said remote electrode comprising part of a transducing capacitor responsive to physical variations, but said dielectric body not being part of said transducing capacitor.
Claim 2
Dependent Claim
78 words
An electret device comprising: a dielectric body provided with electric charges, a conductive electrode secured on one surface of said dielectric body, a cover body comprised of a conductive material and attached on the opposite surface of said dielectric body, and a remote electrode electrically connected to said cover body through a conductive wire, said remote electrode comprising part of a transducing capacitor responsive to physical variations, but said dielectric body not being part of said transducing capacitor.
Claim 3
Dependent Claim
36 words
An electret device according to claim 1, where said dielectric body, conductive electrode and cover body are formed into a rolled figure, and further comprising an insulator situated between said cover body and said conductive electrode.
Claim 4
Dependent Claim
67 words
An electret device comprising: a dielectric body provided with electric charges, a conductive electrode secured on one surface of said dielectric body, a cover body comprised of a conductive material and attached on the opposite surface of said dielectric body, and a transducing capacitor located remote from said dielectric body, said transducing capacitor including a remote electrode electrically connected to said cover body through a conductive wire.
Claim 5
Dependent Claim
67 words
An electret device comprising: a dielectric body provided with electric charges, a conductive electrode secured on one surface of said dielectric body, a cover body comprised of a conductive material and attached on the opposite surface of said dielectric body, and a transducing capacitor located remote from said dielectric body, said transducing capacitor including a remote electrode electrically connected to said cover body through a conductive wire.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-06-19 | 1987-12-19 | 1988-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-06-19 | 1991-12-19 | 1992-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-06-19 | 1995-12-19 | 1996-06-19 | $7700.00 | Window Closed / Lapsed |