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US4972088A Expired / Lapsed US ⏱️ 0.0 years remaining

Register mark detection

Assignee: HCR REALISATIONS Ltd (A BRITISH COMPANY)
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Filing: 1989-03-24
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Granted: 1990-11-20
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Expires: 2009-03-24
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Abstract

Abstract A method of and apparatus for detecting a register mark on an elongate web (3) is described. The web (3) carries a number of copies of an image (4) spaced apart along the web (3) and a region of the path along which the web (3) moves is irradiated with infra-red radiation by a source (5). The region is viewed with a series of detectors (1D-1F) as the web (3) passes through the irradiated region and the output levels of the detectors (1D-1F) are monitored for changes in their output levels. An edge extending transverse to the direction of movement (2) of the web (3) is then selected within the image (4) when the monitored changes in the output levels of all the detectors (1D-1F) satisfy predetermined criteria. The edge is then used for subsequent register control.

Inventors

  • 👤 John H. Weyer
  • 👤 Jeffrey Isherwood

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 07:57
CPC Classifications
B; B41; B41F; B41F13/00; B41F13/02; B41F13/025; B41F33/00; B41F33/0081

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 113 words
A method of detecting a register mark on an elongate web carrying a number of copies of an image spaced apart along said web, said mark being constituted by an edge within said image and extending transverse to the direction of movement of said web, said method comprising irradiating a region of the path along which said web moves in use; viewing, with a plurality of radiation sensitive detectors, said irradiated region as said web passes through said irradiated region; monitoring for changes in the output levels of said detectors; and designating said edge for subsequent register control when said monitored changes in said output levels of all said detectors satisfy predetermined criteria.
Claim 2
Independent Claim 113 words
A method of detecting a register mark on an elongate web carrying a number of copies of an image spaced apart along said web, said mark being constituted by an edge within said image and extending transverse to the direction of movement of said web, said method comprising irradiating a region of the path along which said web moves in use; viewing, with a plurality of radiation sensitive detectors, said irradiated region as said web passes through said irradiated region; monitoring for changes in the output levels of said detectors; and designating said edge for subsequent register control when said monitored changes in said output levels of all said detectors satisfy predetermined criteria.
Claim 3
Dependent Claim 26 words
A method according to claim 1, wherein said designating step comprises designating an edge that runs substantially at right angles to said direction of web movement.
Claim 4
Dependent Claim 69 words
A method according to claim 1, wherein said designating step comprises the step of designating said edge for subsequent register control when said monitored changes in said output levels satisfy said predetermined criteria, including one or more of the rise time, the straightness and orthogonality of said edge, the amplitude of the change, the distance fore and/or aft of said edge clear of similar edges, and the print thickness.
Claim 5
Dependent Claim 35 words
A method according to claim 1, wherein if an edge satisfying said predetermined criteria cannot be detected in a first pass, said method is repeated with said illuminated region either enlarged laterally or shifted laterally.
Claim 6
Dependent Claim 60 words
A method according to claim 1, wherein if an edge cannot be found in a first pass which produce said monitored changes in said output levels which satisfy said predetermined criteria, said method is repeated one or more times, one or more of said criteria being varied on each pass such that different output levels will satisfy the predetermined criteria.
Claim 7
Dependent Claim 34 words
A method according to claim 5, wherein each criterion comprises a threshold with which said output levels from said detectors are compared, said thresholds being selectively decreased in subsequent passes to the predetermined minimum.
Claim 8
Dependent Claim 14 words
A method according to claim 1, wherein said region is irradiated with visible radiation.
Claim 9
Dependent Claim 14 words
A method according to claim 1, wherein said region is irradiated with ultra-violet radiation.
Claim 10
Independent Claim 122 words
A method of controlling movement of an elongage web carrying a number of copies of an image spaced apart along said web, said mark being constituted by an edge within said image and extending transverse to the direction of movement of said web, said method comprising: irradiating a region of the path along which said web moves in use; viewing, with a plurality of radiation sensitive detectors, said irradiated region as said web passes through said irradiated region; monitoring for changes in the output levels of said detectors; designating said edge for subsequent register control when said monitored changes in said output levels of all said detectors satisfy predetermined criteria; and controlling movement of said web in accordance with said designating step.
Claim 11
Independent Claim 122 words
A method of controlling movement of an elongage web carrying a number of copies of an image spaced apart along said web, said mark being constituted by an edge within said image and extending transverse to the direction of movement of said web, said method comprising: irradiating a region of the path along which said web moves in use; viewing, with a plurality of radiation sensitive detectors, said irradiated region as said web passes through said irradiated region; monitoring for changes in the output levels of said detectors; designating said edge for subsequent register control when said monitored changes in said output levels of all said detectors satisfy predetermined criteria; and controlling movement of said web in accordance with said designating step.
Claim 12
Dependent Claim 107 words
Apparatus for detecting a register mark on an elongate web carrying a number of copies of an image spaced apart along said web, said apparatus comprising means for irradiating a region of the path along which said web moves in use; a plurality of radiation sensitive detectors for viewing said irradiated region as said web passes through said region; and processing means for monitoring for changes in the output levels of said detectors, and for selecting an edge extending transverse to the direction of movement of said web for subsequent register control when said monitored changes in said output levels of all said detectors satisfy predetermined criteria.
Claim 13
Dependent Claim 107 words
Apparatus for detecting a register mark on an elongate web carrying a number of copies of an image spaced apart along said web, said apparatus comprising means for irradiating a region of the path along which said web moves in use; a plurality of radiation sensitive detectors for viewing said irradiated region as said web passes through said region; and processing means for monitoring for changes in the output levels of said detectors, and for selecting an edge extending transverse to the direction of movement of said web for subsequent register control when said monitored changes in said output levels of all said detectors satisfy predetermined criteria.

References Cited (Backward Citations)

CH381713A Cited
DE2044306A1 Cited
GB1357648A Cited
US4067760A Cited
US4857745A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-11-19 1994-05-21 1994-11-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-11-19 1998-05-21 1998-11-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-11-19 2002-05-21 2002-11-20 $7700.00 Window Closed / Lapsed

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