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US5075543A Expired / Lapsed US ⏱️ 0.0 years remaining

Light weight paper sensor using fibers

Assignee: Xerox Corp
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Filing: 1990-05-29
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Granted: 1991-12-24
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Expires: 2010-05-29
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Abstract

Abstract An optical sensor in a sheet transport system for detecting a sheet along a paper path. The sensor includes a light beam disposed in an interference relationship with a paper path, the light beam providing a plurality of crossings of the paper path and including a light emitter, a light detector disposed at the end of the light beam path, the light detector responsive to light projected along the light beam path to provide a signal, the signal providing an indication of the presence or absence of a sheet in the light beam path, and an optical fiber providing a portion of the light beam path for redirecting the light beam across the paper path. The light beam is projected at an angle with respect to the paper path, the angle being at least 10 degrees from the perpendicular to the paper path.

Inventors

  • 👤 John E. Courtney

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 19:12
CPC Classifications
G; G01; G01V; G01V8/00; G01V8/10; G01V8/12; G01V8/14

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 179 words
A sheet sensor in a sheet transport system for conveying a sheet along a paper path comprising; a light beam path, the light beam path disposed in an interference relationship with the paper path, the light beam providing a plurality of crossings of the paper path, a light emitter, the light emitter disposed at one end of the light beam path for projecting a light beam along the light beam path, a light detector disposed at the other end of the light beam path, the light detector responsive to light projected along the light beam path to provide a signal, the signal providing an indication of the presence or absence of a sheet in the light beam path, and an optical fiber providing a portion of the light beam path for redirecting the light beam across the paper path, the optical fiber redirecting the light beam for said plurality of crossings, the light beam path being projected at an angle with respect to the paper path, the angle being less than 90 degrees with respect to the paper path.
Claim 2
Dependent Claim 179 words
A sheet sensor in a sheet transport system for conveying a sheet along a paper path comprising; a light beam path, the light beam path disposed in an interference relationship with the paper path, the light beam providing a plurality of crossings of the paper path, a light emitter, the light emitter disposed at one end of the light beam path for projecting a light beam along the light beam path, a light detector disposed at the other end of the light beam path, the light detector responsive to light projected along the light beam path to provide a signal, the signal providing an indication of the presence or absence of a sheet in the light beam path, and an optical fiber providing a portion of the light beam path for redirecting the light beam across the paper path, the optical fiber redirecting the light beam for said plurality of crossings, the light beam path being projected at an angle with respect to the paper path, the angle being less than 90 degrees with respect to the paper path.
Claim 3
Dependent Claim 185 words
A sheet sensor in a sheet transport system for conveying a sheet along a paper path in an image reproduction system comprising a light beam path, the light beam path disposed in an interference relationship with the paper path, the light beam providing a plurality of crossings of the paper path, a light emitter, the light emitter disposed at one end of the light beam path for projecting a light beam along the light beam path, a light detector disposed at the other end of the light beam path, the light detector responsive to light projected along the light beam path to provide a signal, the signal providing an indication of the presence or absence of a sheet in the light beam path, and an optical fiber providing a portion of the light beam path for redirecting the light beam across the paper path, the optical fiber redirecting the light beam for said plurality of crossings, the light beam path being projected at an angle with respect to the paper path, the angle being greater than 20 degrees from the perpendicular to the paper path.
Claim 4
Dependent Claim 185 words
A sheet sensor in a sheet transport system for conveying a sheet along a paper path in an image reproduction system comprising a light beam path, the light beam path disposed in an interference relationship with the paper path, the light beam providing a plurality of crossings of the paper path, a light emitter, the light emitter disposed at one end of the light beam path for projecting a light beam along the light beam path, a light detector disposed at the other end of the light beam path, the light detector responsive to light projected along the light beam path to provide a signal, the signal providing an indication of the presence or absence of a sheet in the light beam path, and an optical fiber providing a portion of the light beam path for redirecting the light beam across the paper path, the optical fiber redirecting the light beam for said plurality of crossings, the light beam path being projected at an angle with respect to the paper path, the angle being greater than 20 degrees from the perpendicular to the paper path.
Claim 5
Dependent Claim 35 words
The sensor of claim 2 wherein the light beam path is projected at an angle with respect to the paper path, the angle being greater than 45 degrees from the perpendicular to the paper path.
Claim 6
Dependent Claim 137 words
In a sheet transport system for conveying a sheet along a paper path in an image reproduction system, a sheet sensor comprising a light beam path, the light beam path disposed in an interference relationship with the paper path, an optical fiber providing a portion of the light beam path, a light emitter, the light emitter disposed at one end of the light beam path for projecting a light beam along the light beam path, a light detector disposed at the other end of the light beam path, the light detector responsive to light projected along the light beam path to provide a signal, the signal depending upon the presence or absence of a sheet in the light beam path, the light beam path being projected at an angle with respect to the perpendicular to paper path.
Claim 7
Dependent Claim 137 words
In a sheet transport system for conveying a sheet along a paper path in an image reproduction system, a sheet sensor comprising a light beam path, the light beam path disposed in an interference relationship with the paper path, an optical fiber providing a portion of the light beam path, a light emitter, the light emitter disposed at one end of the light beam path for projecting a light beam along the light beam path, a light detector disposed at the other end of the light beam path, the light detector responsive to light projected along the light beam path to provide a signal, the signal depending upon the presence or absence of a sheet in the light beam path, the light beam path being projected at an angle with respect to the perpendicular to paper path.
Claim 8
Dependent Claim 21 words
The sheet transpart system claim 4 wherein the optical fiber is a fiber optic U joint for redirecting the light beam.
Claim 9
Dependent Claim 38 words
The sheet sensor claim 4 wherein the light beam path is projected at an angle with respect to the paper path, the angle being in the range of 10 to 60 degrees from the plane of the paper.

References Cited (Backward Citations)

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US3610940A Cited
US3742486A Cited
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US4156149A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-12-23 1995-06-24 1995-12-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-12-23 1999-06-24 1999-12-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-12-23 2003-06-24 2003-12-24 $7700.00 Window Closed / Lapsed

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