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US4748334A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for detecting flaws in knitted fabric

Assignee: Gunze Ltd
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Filing: 1987-04-08
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Granted: 1988-05-31
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Expires: 2007-04-08
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Abstract

Abstract A proposal for detecting flaws not defining normal stitches in a knitted fabric. Fabric detection signals are derived from three detectors arranged to correspond to intervals between lines of thread defining stitches. The detection signals are then added with predetermined weights, and the signals thus weighted are subjected to adding and/or subtracting operations. As a result, the flaws not defining normal stitches in the knitted fabric are detected. According to this proposal, reliable detection is made of not only large flaws such as circular holes but narrow flaws such as runs also.

Inventors

  • 👤 Akira Kobayashi
  • 👤 Tomio Yamaura
  • 👤 Mizuo Nakayama
  • 👤 Hisao Itaya

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 19:46
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/89; G01N21/892; G01N21/898; G01N21/8983; D; D06; D06H; D06H3/00; D06H3/08

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 73 words
A flaw detecting method for detecting flaws not defining normal stitches in a knitted fabric, comprising the steps of; deriving fabric detection signals from three detectors arranged to correspond to intervals between lines of thread defining stitches, adding predetermined weights to the fabric detection signals derived from the detectors, operating the signals thus weighted by adding and/or subtracting the signals, and judging presence and absence of flaw based on results of the operation.
Claim 2
Dependent Claim 73 words
A flaw detecting method for detecting flaws not defining normal stitches in a knitted fabric, comprising the steps of; deriving fabric detection signals from three detectors arranged to correspond to intervals between lines of thread defining stitches, adding predetermined weights to the fabric detection signals derived from the detectors, operating the signals thus weighted by adding and/or subtracting the signals, and judging presence and absence of flaw based on results of the operation.
Claim 3
Dependent Claim 81 words
A flaw detecting apparatus for detecting flaws not defining normal stitches in a knitted fabric, comprising; three detector means arranged to corrspond to intervals between lines of thread defining stitches for outputing detection signals, respectively, weighting means for adding predetermined weights to the detection signals output from the detector means, operating means for adding and/or subtracting the signals thus weighted, and judging means for judging presence and absence of flaws based on results of the operation received from the operating means.
Claim 4
Dependent Claim 81 words
A flaw detecting apparatus for detecting flaws not defining normal stitches in a knitted fabric, comprising; three detector means arranged to corrspond to intervals between lines of thread defining stitches for outputing detection signals, respectively, weighting means for adding predetermined weights to the detection signals output from the detector means, operating means for adding and/or subtracting the signals thus weighted, and judging means for judging presence and absence of flaws based on results of the operation received from the operating means.
Claim 5
Dependent Claim 29 words
A flaw detecting apparatus as claimed in claim 2 wherein each of said detector means comprises a photoelectric sensing element opposed to a light source across the knitted fabric.
Claim 6
Dependent Claim 31 words
A flaw detecting apparatus as claimed in claim 2 wherein said detector means are arranged to correspond to intervals between vertical lines of thread defining the stitches in the knitted fabric.
Claim 7
Dependent Claim 30 words
A flaw detecting apparatus as claimed in claim 3 wherein said light source is disposed inside the knitted fabric and said photoelectric sensing element is disposed outside the knitted fabric.
Claim 8
Dependent Claim 44 words
A flaw detecting apparatus as claimed in claim 2 wherein said weighting means includes a circuit for weighting the detection signal of an intermediate one of the detector means twofold of weighting of the detection signals of the other detector means disposed laterally thereof.
Claim 9
Dependent Claim 31 words
A flaw detecting apparatus as claimed in claim 2 wherein said weighting means includes an analog amplifier for amplifying the detection signal of an intermediate one of the detector means twofold.
Claim 10
Dependent Claim 34 words
A flaw detecting apparatus as claimed in claim 2 wherein said operating means includes a section for detecting narrow flaws such as runs, and a section for detecting large flaws such as circular holes.
Claim 11
Dependent Claim 68 words
A flaw detecting apparatus as claimed in claim 8 wherein said section for detecting narrow flaws carries out an operation (B-A)+(B-C), and said section for detecting large flaws carries out an operation A+B+C, in which B represents a level of the detection signal of the intermediate one of the detector means and A and B represent levels of the detection signals of lefthand and righthand detector means, respectively.

References Cited (Backward Citations)

US3345836A Cited
US4591726A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-05-31 1991-11-30 1992-05-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-05-31 1995-11-30 1996-05-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-05-31 1999-11-30 2000-05-31 $7700.00 Window Closed / Lapsed

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