US5825501A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Structure and yarn sensor for fabric
Assignee: Lockheed Martin Energy Systems Inc
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Filing: 1997-03-14
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Granted: 1998-10-20
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Expires: 2017-03-14
Abstract
Abstract A structure and yarn sensor for fabric directly determines pick density in a fabric thereby allowing fabric length and velocity to be calculated from a count of the picks made by the sensor over known time intervals. The structure and yarn sensor is also capable of detecting full length woven defects and fabric. As a result, an inexpensive on-line pick (or course) density measurement can be performed which allows a loom or knitting machine to be adjusted by either manual or automatic means to maintain closer fiber density tolerances. Such a sensor apparatus dramatically reduces fabric production costs and significantly improves fabric consistency and quality for woven or knitted fabric.
Inventors
- 👤 David K. Mee
- 👤 Glenn O. Allgood
- 👤 Larry R. Mooney
- 👤 Michael G. Duncan
- 👤 John C. Turner
- 👤 Dale A. Treece
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 11:50
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/89; G01N21/892; G01N21/898; G01N21/8983
Claims Analysis
Total Claims: 50
Claim 1
Independent Claim
593 words
A structure and yarn sensor apparatus for use with a fabric made with a plurality of yarns moving in a direction of travel, the fabric having a front side and a back side, the yarns being disposed generally across the width of the fabric, comprising: (A) a light source directed so that light impinges upon a side of the fabric in a path of light propagation; (B) a focusing lens disposed in the path of light propagation to focus the light; (C) an astigmatic lens disposed in the path of light propagation to allow selective imaging of yarn in one dimension to be imaged on an array; (D) an array comprising photodetectors, the array having a face, the photodetectors being disposed so that the focused light from the focusing lens impinges upon the face of the array of photodetectors to produce a scan, wherein the face is divided into a multiplicity of pixels, the array of photodetectors producing an output signal based on the fabric moving in the direction of travel during the scan; (E) a timing control means producing a velocity gate signal, clock signals, a read signal, and a scan start signal, wherein the clock signal and the scan start signal are coupled to the array of photodetectors; (F) a smoothing filter means coupled to the output of the array of photodetectors; (G) a bias detection means coupled to the output of the array of photodetectors; (H) a discriminator means having a positive input and a negative input, wherein one input is coupled to the output of the smoothing filter means and the other input is coupled to the output of the bias detection means; (I) a pick selection and counting means having an input port, a reset port, and clock signal input ports, wherein the input port is coupled to the output of the discriminator port, the reset port is coupled to the scan start signal, and the clock inputs are coupled to the timing control clock signals, and wherein the scan pick selection and counting means determines which picks imaged on the face of the photodetectors during a scan will be used in the density calculation, provides a gated pixels signal during a scan while picks are being counted, provides a pick detected signal during a scan each time an additional pick is counted, and outputs a collected count of picks over multiple scans; (J) a pixel selection and counting means having a reset port, an input port, clock signal input ports, and a pick detected input port, wherein the reset port is coupled to the scan start signal, the input port is coupled to the gated pixels signal, the clock inputs are coupled to the timing control clock signals, and the pick detected import port is coupled to the pick detected output, and wherein the pixel selection and counting means counts pixels during scans corresponding to the count of picks and outputs a collected count of pixels over multiple scans; (K) an incremental pick density determination means having inputs coupled to the read signal, the scan pick selection and counting output and the pixel selection and counting output, wherein the pick density calculation means produces an incremental pick density signal based on the pick count and the pixel count, wherein the pick density signal is representative of the density of picks in the fabric object imaged on the face of the array of photodetectors, and wherein the incremental pick density processor means resets scan pick selection and counting and pixel selection and counting means after performing a read.
Claim 2
Dependent Claim
593 words
A structure and yarn sensor apparatus for use with a fabric made with a plurality of yarns moving in a direction of travel, the fabric having a front side and a back side, the yarns being disposed generally across the width of the fabric, comprising: (A) a light source directed so that light impinges upon a side of the fabric in a path of light propagation; (B) a focusing lens disposed in the path of light propagation to focus the light; (C) an astigmatic lens disposed in the path of light propagation to allow selective imaging of yarn in one dimension to be imaged on an array; (D) an array comprising photodetectors, the array having a face, the photodetectors being disposed so that the focused light from the focusing lens impinges upon the face of the array of photodetectors to produce a scan, wherein the face is divided into a multiplicity of pixels, the array of photodetectors producing an output signal based on the fabric moving in the direction of travel during the scan; (E) a timing control means producing a velocity gate signal, clock signals, a read signal, and a scan start signal, wherein the clock signal and the scan start signal are coupled to the array of photodetectors; (F) a smoothing filter means coupled to the output of the array of photodetectors; (G) a bias detection means coupled to the output of the array of photodetectors; (H) a discriminator means having a positive input and a negative input, wherein one input is coupled to the output of the smoothing filter means and the other input is coupled to the output of the bias detection means; (I) a pick selection and counting means having an input port, a reset port, and clock signal input ports, wherein the input port is coupled to the output of the discriminator port, the reset port is coupled to the scan start signal, and the clock inputs are coupled to the timing control clock signals, and wherein the scan pick selection and counting means determines which picks imaged on the face of the photodetectors during a scan will be used in the density calculation, provides a gated pixels signal during a scan while picks are being counted, provides a pick detected signal during a scan each time an additional pick is counted, and outputs a collected count of picks over multiple scans; (J) a pixel selection and counting means having a reset port, an input port, clock signal input ports, and a pick detected input port, wherein the reset port is coupled to the scan start signal, the input port is coupled to the gated pixels signal, the clock inputs are coupled to the timing control clock signals, and the pick detected import port is coupled to the pick detected output, and wherein the pixel selection and counting means counts pixels during scans corresponding to the count of picks and outputs a collected count of pixels over multiple scans; (K) an incremental pick density determination means having inputs coupled to the read signal, the scan pick selection and counting output and the pixel selection and counting output, wherein the pick density calculation means produces an incremental pick density signal based on the pick count and the pixel count, wherein the pick density signal is representative of the density of picks in the fabric object imaged on the face of the array of photodetectors, and wherein the incremental pick density processor means resets scan pick selection and counting and pixel selection and counting means after performing a read.
Claim 3
Dependent Claim
127 words
An apparatus as described in claim 1, further comprising: (L) a quadrature selection means coupled to the output of the discriminator means, wherein the quadrature selection means produces quadrature outputs means based on the discriminator output during selected pixels; and (M) a phase detector means coupled to the output of the quadrature selection means, wherein the phase detector means produces, based on quadrature signals, one or more pulses for each pick in the fabric imaged on the face of the array which passes a center region of the array, including information on the direction of movement; and (N) an incremental counter means having a pair of inputs from the phase detector wherein an output is provided representing the count of pixels during a selected number of scans.
Claim 4
Dependent Claim
118 words
An apparatus as described in claim 2, further comprising: (O) a pick accumulation and determination means coupled to the incremental counter and having a read input and a user preset input, which provides an accumulated output of the incremental pick counts with the capability of presetting the output based on a user preset input and which resets the incremental counter after reading its count; and (P) a fabric length accumulation and determination means having a preset port and a read port and being coupled to the incremental density output and the incremental counter output, wherein the fabric length accumulation and determination means produces, based on its inputs, a fabric length signal representative of the length of the fabric.
Claim 5
Dependent Claim
57 words
An apparatus as described in claim 2, further comprising: (Q) a fabric velocity calculation means having a read port and a velocity gate port coupled to the average density output and the incremental counter output, wherein the fabric velocity calculation processor produces, based on its inputs, a fabric velocity signal representative of the velocity of the fabric.
Claim 6
Dependent Claim
16 words
An apparatus as described in claim 1, wherein the array of photodetectors comprises a linear array.
Claim 7
Dependent Claim
18 words
An apparatus as described in claim 1, wherein each element of the array of photodetectors comprises a photodiode.
Claim 8
Dependent Claim
19 words
An apparatus as described in claim 1, wherein the focusing lens comprises a nonastigmatic lens and an astigmatic lens.
Claim 9
Dependent Claim
16 words
An apparatus as described in claim 1, wherein the focusing lens comprises a cylindrical convex lens.
Claim 10
Dependent Claim
25 words
An apparatus as described in claim 1, wherein light from the light source impinges upon the side of the fabric opposite the array of photodetectors.
Claim 11
Dependent Claim
26 words
An apparatus as described in claim 1 wherein light from the light source impinges upon the fabric from the same side as the array of photodetectors.
Claim 12
Dependent Claim
34 words
An apparatus as described in claim 1 wherein light from the light source is generated by means selected from the group of means consisting of laser diodes, lasers, halogen lamps, and light emitting diodes.
Claim 13
Independent Claim
228 words
A method for determining a yarn density in a fabric made with a plurality of yarns, the fabric having a front side and a back side, and having yarns which are disposed generally across the width of the fabric, comprising the steps of: (A) moving the fabric in a direction of travel, (B) directing a light source so that light impinges upon the fabric in a path of light propagation; (C) focusing the light so that the light impinges upon an array of photodetectors, wherein the array of photodetectors has a face which is divided into a multiplicity of pixels, wherein a number of yarns in a single direction in the fabric is imaged on a number of pixels in the face of the array of photodetectors to produce a scan; (D) operating the array of photodetectors during a scan to produce an output signal which is based on the fabric moving in the direction of travel during the scan; (E) counting the number of selected yarns in the fabric imaged on the face of the array of photodetectors during the scan; (F) counting the number of pixels in the face of the array of photodetectors on which the number of selected yarns in the fabric is imaged during the scan; and (G) determining the yarn density based on the number of yarns and the number of pixels.
Claim 14
Independent Claim
228 words
A method for determining a yarn density in a fabric made with a plurality of yarns, the fabric having a front side and a back side, and having yarns which are disposed generally across the width of the fabric, comprising the steps of: (A) moving the fabric in a direction of travel, (B) directing a light source so that light impinges upon the fabric in a path of light propagation; (C) focusing the light so that the light impinges upon an array of photodetectors, wherein the array of photodetectors has a face which is divided into a multiplicity of pixels, wherein a number of yarns in a single direction in the fabric is imaged on a number of pixels in the face of the array of photodetectors to produce a scan; (D) operating the array of photodetectors during a scan to produce an output signal which is based on the fabric moving in the direction of travel during the scan; (E) counting the number of selected yarns in the fabric imaged on the face of the array of photodetectors during the scan; (F) counting the number of pixels in the face of the array of photodetectors on which the number of selected yarns in the fabric is imaged during the scan; and (G) determining the yarn density based on the number of yarns and the number of pixels.
Claim 15
Dependent Claim
16 words
A method as described in claim 12, wherein the array of photodetectors comprises a linear array.
Claim 16
Dependent Claim
18 words
A method as described in claim 12, wherein each element of the array of photodetectors comprises a photodiode.
Claim 17
Dependent Claim
29 words
A method as described in claim 12, wherein the step of focusing the light is accomplished by utilizing at least one nonastigmatic lens and at least one astigmatic lens.
Claim 18
Dependent Claim
23 words
A method as described in claim 12, wherein the step of focusing the light is accomplished by utilizing at least one astigmatic lens.
Claim 19
Dependent Claim
25 words
A method as described in claim 12, wherein light from the light source impinges upon the side of the fabric opposite the array of photodetectors.
Claim 20
Dependent Claim
26 words
A method as described in claim 12, wherein light from the light source impinges upon the fabric from the same side as the array of photodetectors.
Claim 21
Dependent Claim
34 words
A method as described in claim 12 wherein light from the light source is generated by means selected from the group of means consisting of laser diodes, lasers, halogen lamps, and light emitting diodes.
Claim 22
Independent Claim
213 words
A method for detecting defects and patterns in a fabric made with a plurality of yarns, the fabric having a front side and a back side, the method comprising the steps of: (A) moving the fabric in a direction of travel; (B) directing a light source so that light impinges upon the fabric in a path of light propagation; (C) focusing the light so that the light impinges upon an array of photodetectors to produce an image upon the array of photodetectors, the image appearing as a set of parallel lines, each line representing one yarn in the fabric, wherein the array of photodetectors has a face which is divided into a multiplicity of pixels, wherein a number of yarns in a single direction in the fabric are imaged on a number of pixels in the face of the array of photodetectors to produce a scan; (D) operating the array of photodetectors during a scan to produce an output signal based on the fabric moving in the direction of travel during the scan; (E) obtaining a signal, based on the output signal from the array of photodetectors; and (F) determining any characteristic selected from the group consisting of defects and patterns in the fabric based on the signal from the array of photodetectors.
Claim 23
Independent Claim
213 words
A method for detecting defects and patterns in a fabric made with a plurality of yarns, the fabric having a front side and a back side, the method comprising the steps of: (A) moving the fabric in a direction of travel; (B) directing a light source so that light impinges upon the fabric in a path of light propagation; (C) focusing the light so that the light impinges upon an array of photodetectors to produce an image upon the array of photodetectors, the image appearing as a set of parallel lines, each line representing one yarn in the fabric, wherein the array of photodetectors has a face which is divided into a multiplicity of pixels, wherein a number of yarns in a single direction in the fabric are imaged on a number of pixels in the face of the array of photodetectors to produce a scan; (D) operating the array of photodetectors during a scan to produce an output signal based on the fabric moving in the direction of travel during the scan; (E) obtaining a signal, based on the output signal from the array of photodetectors; and (F) determining any characteristic selected from the group consisting of defects and patterns in the fabric based on the signal from the array of photodetectors.
Claim 24
Dependent Claim
16 words
A method as described in claim 20, wherein the array of photodetectors comprises a linear array.
Claim 25
Dependent Claim
17 words
A method as described in claim 20, wherein each of the array of photodetectors comprises a photodiode.
Claim 26
Dependent Claim
23 words
A method as described in claim 20, wherein the step of focusing the light is accomplished by utilizing a pair of plano-convex lenses.
Claim 27
Dependent Claim
29 words
A method as described in claim 20, wherein the step of focusing the light is accomplished by utilizing at least one nonastigmatic lens and at least one astigmatic lens.
Claim 28
Dependent Claim
23 words
A method as described in claim 20, wherein the step of focusing the light is accomplished by utilizing at least one astigmatic lens.
Claim 29
Dependent Claim
25 words
A method as described in claim 20, wherein light from the light source impinges upon the side of the fabric opposite the array of photodetectors.
Claim 30
Dependent Claim
26 words
A method as described in claim 20 wherein light from the light source impinges upon the fabric from the same side as the array of photodetectors.
Claim 31
Dependent Claim
34 words
A method as described in claim 20 wherein light from the light source is generated by means selected from the group of means consisting of laser diodes, lasers, halogen lamps, and light emitting diodes.
Claim 32
Independent Claim
320 words
A method for determining at least one parameter selected from the group consisting of fabric length and fabric velocity in a fabric made with a plurality of yarns during a period of elapsed time, the fabric having a front side and a back side, the method comprising the steps of: (A) moving the fabric in a direction of travel; (B) directing a light source so that light impinges upon the fabric in a path of light propagation; (C) focusing the light so that the light impinges upon an array of photodetectors to produce an image upon the array of photodetectors, the image appearing as a set of parallel lines, each line representing one yarn in the fabric, wherein the array of photodetectors has a face which is divided into a multiplicity of pixels, wherein a number of yarns in a single direction in the fabric are imaged on a number of pixels in the face of the array of photodetectors to produce a scan; (D) operating the array of photodetectors during a scan to produce an output signal based on the fabric moving in the direction of travel during the scan; (E) counting yarns in the fabric imaged on the face of the array of photodetectors as they pass at least one pixel to determine yarn count; (F) counting the number of selected yarns in the fabric imaged on the face of the array of photodetectors during the scan; (G) counting the number of pixels in the face of the array of photodetectors on which the number of selected yarns in the fabric is imaged during the scan; (H) determining the yarn density based on the number of yarns and the number of pixels and (I) determining said at least one parameter selected from the group consisting of fabric length and fabric velocity based on at least two of the group consisting of yarn count, yarn density, and elapsed time.
Claim 33
Independent Claim
320 words
A method for determining at least one parameter selected from the group consisting of fabric length and fabric velocity in a fabric made with a plurality of yarns during a period of elapsed time, the fabric having a front side and a back side, the method comprising the steps of: (A) moving the fabric in a direction of travel; (B) directing a light source so that light impinges upon the fabric in a path of light propagation; (C) focusing the light so that the light impinges upon an array of photodetectors to produce an image upon the array of photodetectors, the image appearing as a set of parallel lines, each line representing one yarn in the fabric, wherein the array of photodetectors has a face which is divided into a multiplicity of pixels, wherein a number of yarns in a single direction in the fabric are imaged on a number of pixels in the face of the array of photodetectors to produce a scan; (D) operating the array of photodetectors during a scan to produce an output signal based on the fabric moving in the direction of travel during the scan; (E) counting yarns in the fabric imaged on the face of the array of photodetectors as they pass at least one pixel to determine yarn count; (F) counting the number of selected yarns in the fabric imaged on the face of the array of photodetectors during the scan; (G) counting the number of pixels in the face of the array of photodetectors on which the number of selected yarns in the fabric is imaged during the scan; (H) determining the yarn density based on the number of yarns and the number of pixels and (I) determining said at least one parameter selected from the group consisting of fabric length and fabric velocity based on at least two of the group consisting of yarn count, yarn density, and elapsed time.
Claim 34
Dependent Claim
16 words
A method as described in claim 29 wherein the array of photodetectors comprises a linear array.
Claim 35
Dependent Claim
13 words
A method as described in claim 29, wherein each photodetector comprises a photodiode.
Claim 36
Dependent Claim
23 words
A method as described in claim 29 wherein the step of focusing the light is accomplished by utilizing a pair of plano-convex lenses.
Claim 37
Dependent Claim
29 words
A method as described in claim 29 wherein the step of focusing the light is accomplished by utilizing at least one nonastigmatic lens and at least one astigmatic lens.
Claim 38
Dependent Claim
23 words
A method as described in claim 29 wherein the step of focusing the light is accomplished by utilizing at least one astigmatic lens.
Claim 39
Dependent Claim
23 words
A method as described in claim 29 wherein the light from the light source impinges upon the fabric opposite the array of photodetectors.
Claim 40
Dependent Claim
27 words
A method as described in claim 29 wherein the light from the light source impinges upon the fabric from the same side as the array of photodetectors.
Claim 41
Dependent Claim
34 words
A method as described in claim 29 wherein light from the light source is generated by means selected from the group of means consisting of laser diodes, lasers, halogen lamps, and light emitting diodes.
Claim 42
Independent Claim
154 words
A method for determining yarn count in a fabric made with a plurality of yarns during a period of elapsed time, the fabric having a front side and a back side, the method comprising the steps of: (A) moving the fabric in a direction of travel; (B) directing a light source so that light impinges upon the fabric in a path of light propagation; (C) focusing the light so that the light impinges upon at least one photodetector to produce an image, the image appearing as a set of parallel lines, each line representing one yarn in the fabric; (D) operating the at least one photodetector to produce an output signal based on the fabric moving in the direction of travel; and (E) counting yarns in the fabric imaged on the at least one photodetector as the image passes the at least one photodetector during the period of elapsed time to determine yarn count.
Claim 43
Independent Claim
154 words
A method for determining yarn count in a fabric made with a plurality of yarns during a period of elapsed time, the fabric having a front side and a back side, the method comprising the steps of: (A) moving the fabric in a direction of travel; (B) directing a light source so that light impinges upon the fabric in a path of light propagation; (C) focusing the light so that the light impinges upon at least one photodetector to produce an image, the image appearing as a set of parallel lines, each line representing one yarn in the fabric; (D) operating the at least one photodetector to produce an output signal based on the fabric moving in the direction of travel; and (E) counting yarns in the fabric imaged on the at least one photodetector as the image passes the at least one photodetector during the period of elapsed time to determine yarn count.
Claim 44
Dependent Claim
16 words
A method as described in claim 38, wherein each at least one photodetector comprises a photodiode.
Claim 45
Dependent Claim
23 words
A method as described in claim 38 wherein the step of focusing the light is accomplished by utilizing a pair of plano-convex lenses.
Claim 46
Dependent Claim
29 words
A method as described in claim 38 wherein the step of focusing the light is accomplished by utilizing at least one nonastigmatic lens and at least one astigmatic lens.
Claim 47
Dependent Claim
23 words
A method as described in claim 38 wherein the step of focusing the light is accomplished by utilizing at least one astigmatic lens.
Claim 48
Dependent Claim
24 words
A method as described in claim 38 wherein the light from the light source impinges upon the fabric opposite the at least one photodetector.
Claim 49
Dependent Claim
28 words
A method as described in claim 38 wherein the light from the light source impinges upon the fabric from the same side as the at least one photodetector.
Claim 50
Dependent Claim
34 words
A method as described in claim 38 wherein light from the light source is generated by means selected from the group of means consisting of laser diodes, lasers, halogen lamps, and light emitting diodes.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2001-10-19 | 2002-04-20 | 2002-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-10-19 | 2006-04-20 | 2006-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-10-19 | 2010-04-20 | 2010-10-20 | $7700.00 | Window Closed / Lapsed |