US3908098A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic transducer
Assignee: Sony Corp
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Filing: 1973-07-30
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Granted: 1975-09-23
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Expires: 1993-07-30
Abstract
Abstract An electrostatic transducer comprises a back plate electrode having a plurality of apertures therein and a diaphragm disposed on the back plate electrode. Each aperture has a counterbore tapering at its top portion which faces the diaphragm, and the top surface of the back plate electrode is formed with roughness.
Inventors
- 👤 Hirotake Kawakami
- 👤 Yoshihiro Yokoyama
- 👤 Tooru Fukumoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 13:45
CPC Classifications
H; H04; H04R; H04R19/00
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
77 words
An electrostatic transducer comprising: a housing, a planar base having a plurality of apertures therethrough, said apertures having smooth counterbores tapered between 10* to 40* providing outwardly flaring openings on one side and the remaining portions of said one side formed with numerous bumps, an electrical conductive surface formed on said base in said smooth counterbores and said remaining portions, and an electrically conductive diaphragm mounted in said housing in closely spaced position above said one side.
Claim 2
Dependent Claim
77 words
An electrostatic transducer comprising: a housing, a planar base having a plurality of apertures therethrough, said apertures having smooth counterbores tapered between 10* to 40* providing outwardly flaring openings on one side and the remaining portions of said one side formed with numerous bumps, an electrical conductive surface formed on said base in said smooth counterbores and said remaining portions, and an electrically conductive diaphragm mounted in said housing in closely spaced position above said one side.
Claim 3
Dependent Claim
21 words
An electrostatic transducer according to claim 1 wherein said openings are flared at an angle of 30* relative to said diaphragm.
Claim 4
Dependent Claim
35 words
An electrostatic transducer according to claim 1, in which a central metal stud extends through said planar base and in electrical contact with said electrical conductive surface and provides the electrical connection to said surface.
Claim 5
Dependent Claim
126 words
An electrostatic transducer comprising: a housing, a flexible diaphragm of a conductive material supported by said housing, a planar back plate assembly mounted in said housing adjacent said diaphragm, said back plate assembly having a plurality of apertures therein which apertures have smooth counterbored tapered openings on the side facing said diaphragm and the tapered openings are tapered at an angle between 10* to 40* relative to said diaphragm, said back plate assembly provided with a roughened surface thereon facing said diaphrAgm; and said back plate assembly comprises an insulating member of a resin and a conductive layer coated on said roughened surface and the smooth tapered surfaces of said counterbored openings to provide a sensitive transducer having a flat frequency response up to 50,000 hertz.
Claim 6
Dependent Claim
126 words
An electrostatic transducer comprising: a housing, a flexible diaphragm of a conductive material supported by said housing, a planar back plate assembly mounted in said housing adjacent said diaphragm, said back plate assembly having a plurality of apertures therein which apertures have smooth counterbored tapered openings on the side facing said diaphragm and the tapered openings are tapered at an angle between 10* to 40* relative to said diaphragm, said back plate assembly provided with a roughened surface thereon facing said diaphrAgm; and said back plate assembly comprises an insulating member of a resin and a conductive layer coated on said roughened surface and the smooth tapered surfaces of said counterbored openings to provide a sensitive transducer having a flat frequency response up to 50,000 hertz.
Claim 7
Dependent Claim
23 words
An electrostatic transducer according to claim 4 wherein said tapered openings are tapered at an angle of 30* relative to said flexible diaphragm.
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) | 1978-09-22 | 1979-03-24 | 1979-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-22 | 1983-03-24 | 1983-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-22 | 1987-03-24 | 1987-09-23 | $7700.00 | Window Closed / Lapsed |