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US3701534A Expired / Lapsed US ⏱️ 0.0 years remaining

Photoelectric switching device for record players

Assignee: DEWEK VEREINIGTE DEUTSCHE ELECTRONIC-WERKE GmbH
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Filing: 1969-11-25
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Granted: 1972-10-31
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Expires: 1989-11-25
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Abstract

Abstract A light electric switching device for a record playing apparatus, which comprises a tone arm which is swingably mounted about a vertical axis for sensing the surface of a record. A mirror is secured close to the vertical axis of the tone arm and with its plane perpendicular to a radial plane of the vertical swinging axis of said tone arm. A light source and a light electric transmitter are provided, to constitute two elements. Both elements are immovably disposed on the record playing device and disposed opposite the mirror, such that a light beam emitted from said light source reflected from the mirror impinges upon the light sensitive transmitter, as soon as the tone arm is disposed within the range of the exit groove of the record.

Inventors

  • 👤 Eckhard Laue

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 17:42
CPC Classifications
G; G11; G11B; G11B19/00; G11B19/02; G11B19/14

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 185 words
A light electric switching device for a record playing apparatus, comprising a rod pivotally mounted about a vertical axis, a tone arm operatively mounted to said rod for pivoting about said vertical axis and for sensing the surface of a record, a mirror secured on said rod of said tone arm and with its plane perpendicular to a radial plane of said vertical axis of said tone arm and said mirror Pivoting with the pivoting of said tone arm, a light source and a photo electric transmitter constituting two elements, both of said two elements being immovably disposed on said record playing apparatus and disposed at a position opposite to said mirror, such that a light beam emitted from said light source reflected from said mirror impinges upon said photo electric transmitter, as soon as said tone arm is disposed within the range of the exit groove of said record, said mirror contains at least one non-reflecting stripe disposed crosswise to its direction of movement, and said photo electric transmitter contains non-transparent stripes on its light-sensitive surface corresponding with said nonreflecting stripes of said mirror.
Claim 2
Dependent Claim 185 words
A light electric switching device for a record playing apparatus, comprising a rod pivotally mounted about a vertical axis, a tone arm operatively mounted to said rod for pivoting about said vertical axis and for sensing the surface of a record, a mirror secured on said rod of said tone arm and with its plane perpendicular to a radial plane of said vertical axis of said tone arm and said mirror Pivoting with the pivoting of said tone arm, a light source and a photo electric transmitter constituting two elements, both of said two elements being immovably disposed on said record playing apparatus and disposed at a position opposite to said mirror, such that a light beam emitted from said light source reflected from said mirror impinges upon said photo electric transmitter, as soon as said tone arm is disposed within the range of the exit groove of said record, said mirror contains at least one non-reflecting stripe disposed crosswise to its direction of movement, and said photo electric transmitter contains non-transparent stripes on its light-sensitive surface corresponding with said nonreflecting stripes of said mirror.

References Cited (Backward Citations)

US2056372A Cited
US2085582A Cited
US2602668A Cited
US3524067A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1975-10-31 1976-05-01 1976-10-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1979-10-31 1980-05-01 1980-10-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1983-10-31 1984-05-01 1984-10-31 $7700.00 Window Closed / Lapsed

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