Patent US3665124A successfully refreshed from Google Patents.
US3665124A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Loudspeaker having annular diaphragm with double voice coil
Assignee: Nippon Gakki Co Ltd
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Filing: 1969-12-23
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Granted: 1972-05-23
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Expires: 1989-12-23
Abstract
Abstract A loudspeaker comprising an annular diaphragm including a vibrating portion having an arcuate shape in cross section, such as a shape of a fraction of a circle or an ellipse, and inner and outer peripheral support portions, voice coils attached to borders between said vibrating portion and said inner and outer support portions of the diaphragm and magnetic circuit means having concentric gaps for receiving said voice coils, respectively, to drive the diaphragm in phase with said voice coils.
Inventors
- 👤 Hiromi Sotome
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:13
CPC Classifications
H; H04; H04R; H04R9/00; H04R9/06; H04R9/063
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
127 words
A loudspeaker comprising: a. an annular diaphragm including a single vibrating portion having an arcuate cross section generated about an axis of revolution external to said arcuate cross seCtion and coincident with the center of radius of said annular diaphragm, and inner and outer support portions, said diaphragm further having inner and outer projecting rim portions extending from said annular diaphragm between said vibrating portion and said inner and outer support portions respectively; b. first and second voice coils attached to said inner and outer projecting rim portions respectively, said first and second coils driving said diaphragm in phase therewith, and c. magnetic circuit means having inner and outer concentric gaps, said first and second voice coils being positioned within said inner and outer concentric gaps respectively.
Claim 2
Dependent Claim
127 words
A loudspeaker comprising: a. an annular diaphragm including a single vibrating portion having an arcuate cross section generated about an axis of revolution external to said arcuate cross seCtion and coincident with the center of radius of said annular diaphragm, and inner and outer support portions, said diaphragm further having inner and outer projecting rim portions extending from said annular diaphragm between said vibrating portion and said inner and outer support portions respectively; b. first and second voice coils attached to said inner and outer projecting rim portions respectively, said first and second coils driving said diaphragm in phase therewith, and c. magnetic circuit means having inner and outer concentric gaps, said first and second voice coils being positioned within said inner and outer concentric gaps respectively.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-23 | 1975-11-22 | 1976-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-23 | 1979-11-22 | 1980-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-23 | 1983-11-22 | 1984-05-23 | $7700.00 | Window Closed / Lapsed |