Patent US5272239A successfully refreshed from Google Patents.
US4160133A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Moving voice coil loudspeaker with magnetic damping increasing at large excursions
Assignee: Individual
•
Filing: 1978-03-01
•
Granted: 1979-07-03
•
Expires: 1998-03-01
Abstract
Abstract There is provided an electrodynamical loudspeaker comprising a voice coil fixed to a diaphragm and resiliently suspended for oscillation in the air gap of a magnet system, and wherein a short-circuit ring is provided at at least one end of the voice coil. The or each short-circuit ring may consist of solid, electrically conducting material or it may consist of a number of turns of electrically conducting material and with short-circuited end points.
Inventors
- 👤 Tore H. Wiik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:52
CPC Classifications
H; H04; H04R; H04R9/00; H04R9/02
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
93 words
An electrodynamical loudspeaker comprising: a voice coil; a diaphragm to which said voice coil is fixed, a magnet system having an air gap in which said voice coil is resiliently suspended for oscillatory movement to either side from a neutral position, and a short-circuit ring at least one end of said voice coil, wherein said short-circuit ring is disposed in such a position relative to a central portion of said voice coil that it is located outside the air gap of said magnet system when said voice coil is in its neutral position.
Claim 2
Dependent Claim
93 words
An electrodynamical loudspeaker comprising: a voice coil; a diaphragm to which said voice coil is fixed, a magnet system having an air gap in which said voice coil is resiliently suspended for oscillatory movement to either side from a neutral position, and a short-circuit ring at least one end of said voice coil, wherein said short-circuit ring is disposed in such a position relative to a central portion of said voice coil that it is located outside the air gap of said magnet system when said voice coil is in its neutral position.
Claim 3
Dependent Claim
30 words
An electrodynamical loudspeaker according to claim 1 wherein said short circuit ring consists of a wire of copper or other conductive material of which the adjacent ends are joined together.
Claim 4
Dependent Claim
23 words
An electrodynamical loudspeaker according to claim 1, wherein said short-circuit ring consists of a solid ring of aluminium or other electrically conductive material.
Claim 5
Dependent Claim
30 words
An electrodynamical loudspeaker according to claim 1, wherein said short-circuit ring is constituted by a coil comprising a number of turns of electrically conductive material and with short-circuited end points.
Claim 6
Dependent Claim
27 words
An electrodynamical loudspeaker according to claim 1, wherein said short-circuit ring is constituted by a number of short-circuited turns on said voice coil at an end thereof.
References Cited (Backward Citations)
US1767837A
Cited
US2269284A
Cited
FR864516A
Cited
US2489862A
Cited
US2556816A
Cited
US2769942A
Cited
DE1512727A1
Cited
SU478457A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-07-02 | 1983-01-01 | 1983-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-07-02 | 1987-01-01 | 1987-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-07-02 | 1991-01-01 | 1991-07-03 | $7700.00 | Window Closed / Lapsed |