US3918722A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tone arm
Assignee: Sony Corp
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Filing: 1974-07-03
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Granted: 1975-11-11
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Expires: 1994-07-03
Abstract
Abstract A tone arm for a phonograph comprising an elongated member composed of carbonaceous fibers held in place by means of a binder. The invention also deals with a method of manufacturing such a tone arm by winding one or more resin impregnated sheets of carbonaceous fiber about a flexible mandrel, positioning the wound mandrel in a mold, applying heat and pressure to the wound mandrel in the mold, withdrawing the mandrel from the mold while the mold is still in its heated condition, and thereafter opening the mold and withdrawing therefrom a solidified tone arm.
Inventors
- 👤 Heitaro Nakajima
- 👤 Hirotake Kawakami
- 👤 Shiyokichi Tatara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:08
CPC Classifications
G; G11; G11B; G11B3/00; G11B3/02; G11B3/10; G11B3/30; G11B3/31
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
67 words
A tone arm for use with a phonograph, said tone arm being composed of fibers composed of carbon held in place by means of a resinous binder, said arm being elongated and having at one end a stylus mounted thereto and being pivotally mounted near the opposite end, said tone arm having a resonant frequency which does not coincide with the noise frequencies generated by eccentric records.
Claim 2
Dependent Claim
67 words
A tone arm for use with a phonograph, said tone arm being composed of fibers composed of carbon held in place by means of a resinous binder, said arm being elongated and having at one end a stylus mounted thereto and being pivotally mounted near the opposite end, said tone arm having a resonant frequency which does not coincide with the noise frequencies generated by eccentric records.
Claim 3
Dependent Claim
15 words
A tone arm according to claim 1, in which the binder is a thermosetting resin.
Claim 4
Dependent Claim
27 words
A tone arm according to claim 1, in which at least some of said fibers are disposed at angles which intersect the major axis of said member.
Claim 5
Dependent Claim
49 words
A tone arm according to claim 1, in which said fibers are contained in a plurality of laminated plies, the fibers in one of said plies being oriented along the major axis of said member, and the fibers in another of said plies being oriented in a different direction.
Claim 6
Dependent Claim
13 words
A tone arm according to claim 1, in which said member is tubular.
Claim 7
Dependent Claim
13 words
A tone arm according to claim 1, which includes an offset end portion.
Claim 8
Dependent Claim
19 words
A tone arm according to claim 1, in which the elongated arm includes a woven fabric of said fibers.
Claim 9
Dependent Claim
79 words
A tone arm for use with a phonograph, said tone arm being composed of fibers composed of carbon held in place by means of a resinous binder, said held together fibers being laminated onto a metallic tube, said arm being elongated and having at one end a stylus mounted thereto and having means for pivotal mounting near the opposite end, said tone arm having a resonant frequency which does not coincide with the noise frequencies generated by eccentric records.
Claim 10
Dependent Claim
79 words
A tone arm for use with a phonograph, said tone arm being composed of fibers composed of carbon held in place by means of a resinous binder, said held together fibers being laminated onto a metallic tube, said arm being elongated and having at one end a stylus mounted thereto and having means for pivotal mounting near the opposite end, said tone arm having a resonant frequency which does not coincide with the noise frequencies generated by eccentric records.
Claim 11
Dependent Claim
19 words
A tone arm according to claim 8 in which said carbon fibers are in the form of woven fabric.
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) | 1978-11-10 | 1979-05-12 | 1979-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-10 | 1983-05-12 | 1983-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-10 | 1987-05-12 | 1987-11-11 | $7700.00 | Window Closed / Lapsed |