Patent US5487521A successfully refreshed from Google Patents.
Patent US3740496A successfully refreshed from Google Patents.
US3740496A
Expired / Lapsed
US
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Diaphragm assembly for electret transducer
Assignee: Knowles Electronics LLC
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Filing: 1971-11-08
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Granted: 1973-06-19
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Expires: 1991-11-08
Abstract
Abstract A diaphragm assembly for an electret transducer wherein the diaphragm comprises a movable plate, and a compliant surround on the periphery of the plate. The diaphragm rests on supporting members of a backplate and is positioned to obtain a suitable stiffness of the vibrating portions without the use of a taut or tensioned diaphragm.
Inventors
- 👤 E Carlson
- 👤 Clifford Killion Mead
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:27
CPC Classifications
H; H04; H04R; H04R19/00
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
65 words
A diaphragm assembly for an electret transducer comprising in combination, a central vibratable plate portion, a compliant surround on the periphery of said plate, a backplate having spaced supports on its surface on which said plate rests, said surround locating said diaphragm plate in proper position on said backplate and enabling the operation of said plate to be independent of temperature, humidity or aging parameters.
Claim 2
Dependent Claim
65 words
A diaphragm assembly for an electret transducer comprising in combination, a central vibratable plate portion, a compliant surround on the periphery of said plate, a backplate having spaced supports on its surface on which said plate rests, said surround locating said diaphragm plate in proper position on said backplate and enabling the operation of said plate to be independent of temperature, humidity or aging parameters.
Claim 3
Dependent Claim
28 words
An apparatus as in claim 1 wherein said electret transducer includes at least two principal sound cavities and said surround acoustically seals one cavity from the other cavity.
Claim 4
Dependent Claim
32 words
An apparatus as in claim 1 wherein said surround comprises a roll portion which extends upwardly then extends downwardly from the plane of said plate and a foot for providing attaching means.
Claim 5
Dependent Claim
25 words
An apparatus as in claim 1 wherein said plate comprises a dielectric sheet material, and a metalizing coating is on the surface adjacent said supports.
Claim 6
Dependent Claim
26 words
An apparatus as in claim 1 wherein said plate comprises a sheet of dielectric material, and a metalizing coating is on both sides of said sheet.
Claim 7
Dependent Claim
26 words
An apparatus as in claim 1 wherein said plate and said surround comprise laminated sheets with the surround being of relatively thinner cross-section than said plate.
Claim 8
Dependent Claim
13 words
An apparatus as in claim 1 wherein said plate portion comprises an electret.
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) | 1976-06-18 | 1976-12-18 | 1977-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-18 | 1980-12-18 | 1981-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-18 | 1984-12-18 | 1985-06-19 | $7700.00 | Window Closed / Lapsed |