US3873783A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Universal stylus arm pivot coupling
Assignee: RCA Corp
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Filing: 1974-03-28
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Granted: 1975-03-25
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Expires: 1994-03-28
Abstract
Abstract In a video disc playback system including a motorboard, a turntable, an information disc, a stylus, a stylus arm, and a stylus arm carrying structure, a universal stylus arm pivot coupling is provided for coupling the stylus arm to the carrying structure. The coupling comprises a generally horseshoe-shaped stylus arm holder affixed to the stylus arm. A plug, having a tapered end with a substantially circular cross-section, is fastened to the first leg of the arm holder. A support member, also generally horseshoe-shaped, is attached to the carrying structure. An opening, having dimensions permitting only a partial entry of and presenting complementary bearing surfaces for smooth engagement with the plug, is disposed in the first leg of the support member. A spring is connected between the second legs of, respectively, the arm holder and the support member. The spring member persistently urges the plug into the opening and provides tracking pressure between the stylus and the disc during playback.
Inventors
- 👤 Marvin Allan Leedom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:09
CPC Classifications
G; G11; G11B; G11B9/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
227 words
In a playback system including a board, a turntable mounted for rotation relative to said board, said turntable having a surface adapted to receive a disc, said disc including a spiral groove with information recorded therein, a stylus arm, a stylus subject to positioning in said spiral groove for recovering said information, said stylus being affixed to a free end of said stylus arm, and a stylus arm carrying structure linked to said board; a universal stylus arm pivot coupling, comprising: a generally horseshoe-shaped stylus arm holder affixed to the end of said stylus arm remote from said free end; a plug having a tapered end with substantially circular crosssection, said plug being fastened to a first leg of said stylus arm holder; a generally horseshoe-shaped support member attached to said stylus arm carrying structure, an opening being disposed in a first leg of said support member and having dimensions permitting only a partial entry of and presenting complementary bearing surfaces for smooth engagement with said plug; and a spring member coupled between the second legs of said stylus arm holder and said support member, said spring member during operation of said coupling continuously urging said plug into said opening and further tending to align the axis of said plug with the axis of said spring member thereby tending to minimize the strain in said spring member.
Claim 2
Dependent Claim
227 words
In a playback system including a board, a turntable mounted for rotation relative to said board, said turntable having a surface adapted to receive a disc, said disc including a spiral groove with information recorded therein, a stylus arm, a stylus subject to positioning in said spiral groove for recovering said information, said stylus being affixed to a free end of said stylus arm, and a stylus arm carrying structure linked to said board; a universal stylus arm pivot coupling, comprising: a generally horseshoe-shaped stylus arm holder affixed to the end of said stylus arm remote from said free end; a plug having a tapered end with substantially circular crosssection, said plug being fastened to a first leg of said stylus arm holder; a generally horseshoe-shaped support member attached to said stylus arm carrying structure, an opening being disposed in a first leg of said support member and having dimensions permitting only a partial entry of and presenting complementary bearing surfaces for smooth engagement with said plug; and a spring member coupled between the second legs of said stylus arm holder and said support member, said spring member during operation of said coupling continuously urging said plug into said opening and further tending to align the axis of said plug with the axis of said spring member thereby tending to minimize the strain in said spring member.
Claim 3
Dependent Claim
29 words
A system as defined in claim 1 including further means for adjusting the distance between the legs of said support member for varying the tension in said spring member.
Claim 4
Dependent Claim
38 words
A system as defined in claim 1 wherein the angle subtended between the axis of said plug and the axis of said spring is adjustable to control the tracking pressure between said stylus and said disc during playback.
Claim 5
Dependent Claim
75 words
A system as defined in claim 3 wherein said spring includes first and second terminal portions for embracing respective ones of said second legs, and wherein at least one of said second legs includes a plurality of parallel notches each dimensioned for reception of a terminal portion of said spring, whereby said adjustment of said tracking pressure may be affected by orienting said spring for terminal portion reception in a selected one of said notches.
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) | 1978-03-24 | 1978-09-23 | 1979-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-24 | 1982-09-23 | 1983-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-24 | 1986-09-23 | 1987-03-25 | $7700.00 | Window Closed / Lapsed |