US4869187A
Expired / Lapsed
US
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Sewing machine having sewing forces measurement system
Assignee: North Carolina State University
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Filing: 1988-06-29
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Granted: 1989-09-26
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Expires: 2008-06-29
Abstract
Abstract A sewing machine having a presser bar and a needle bar and each having a force transducer mounted thereon for simultaneously detecting changes in load applied to the presser bar and needle bar. The force transducers are connected to a circuit including a computer for monitoring the fabric feeding and stitch formation forces encountered by the presser bar and the needle bar during sewing and analyzing the simultaneous force signal data from the force transducers on the needle bar and the presser bar of the sewing machine.
Inventors
- 👤 Trevor J. Little
- 👤 B. Ann Matthews
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:18
CPC Classifications
D; D05; D05B; D05B81/00; D05B29/00; D05B29/02; D05B55/00
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
116 words
In a sewing machine having a presser bar on one end of which a presser foot is secured above a sewing station and a needle bar on one end of which a needle is secured for cooperatively engaging the sewing station, a force measuring system comprising: first force measurement means mounted on said presser bar for measuring forces applied to the presser bar during sewing; second force measurement means mounted on said needle bar for measuring forces applied to the needle bar during sewing; and circuit means electrically connected to said first and second force measurement means for monitoring fabric feeding and stitch formation forces encountered by the presser bar and the needle bar during sewing.
Claim 2
Dependent Claim
116 words
In a sewing machine having a presser bar on one end of which a presser foot is secured above a sewing station and a needle bar on one end of which a needle is secured for cooperatively engaging the sewing station, a force measuring system comprising: first force measurement means mounted on said presser bar for measuring forces applied to the presser bar during sewing; second force measurement means mounted on said needle bar for measuring forces applied to the needle bar during sewing; and circuit means electrically connected to said first and second force measurement means for monitoring fabric feeding and stitch formation forces encountered by the presser bar and the needle bar during sewing.
Claim 3
Dependent Claim
21 words
In a sewing machine according to claim 1 wherein said first and second force measurement means each comprise a force transducer.
Claim 4
Dependent Claim
16 words
In a sewing machine according to claim 2 wherein said force transducers are piezoelectric load washers.
Claim 5
Dependent Claim
39 words
In a sewing machine according to claim 1 wherein said circuit means comprises an oscilloscope electrically connected to said first and second force measurement means for displaying the forces encountered by the presser bar and needle bar during sewing.
Claim 6
Dependent Claim
36 words
In a sewing machine according to claim 4 wherein said oscilloscope is a recording digital oscilloscope providing for real time display of the waveform of presser bar forces and needle bar forces and digital recordation thereof.
Claim 7
Dependent Claim
44 words
In a sewing machine according to claim 4 wherein said circuit means includes an electrical amplifier in electrical connection between said first force measurement means and said oscilloscope and an electrical amplifier in electrical connection between said second force measurement means and said oscilloscope.
Claim 8
Dependent Claim
21 words
In a sewing machine according to claim 4 wherein said circuit means includes an X-Y plotter electrically connected to said oscilloscope.
Claim 9
Dependent Claim
33 words
In a sewing machine according to claim 4 wherein said circuit means includes a computer electrically connected to said oscilloscope for analyzing the force measured by said first and second force measurement means.
Claim 10
Dependent Claim
22 words
In a sewing machine according to claim 8 wherein said computer comprises a selectively programmed personal computer and an electrically connected printer.
Claim 11
Dependent Claim
30 words
In a sewing machine according to claim 1 wherein said circuit means comprises a microprocessor for monitoring and analyzing the forces measured by said first and second force measurement means.
Claim 12
Dependent Claim
129 words
In a sewing machine having a presser bar on one end of which a presser foot is secured above a sewing station and a needle bar on one end of which a needle is secured for cooperatively engaging the sewing station, a force measuring system comprising: a transducer mounted on said presser bar for measuring forces applied to the presser bar during sewing; a transducer mounted on said needle bar for measuring forces applied to the needle bar during sewing; circuit means electrically connected to said first and second transducers for monitoring fabric feeding and stitch formation forces encountered by the presser bar and the needle bar during sewing; and computer means electrically connected to said circuit means for analyzing the forces measured by said first and second transducers.
Claim 13
Dependent Claim
129 words
In a sewing machine having a presser bar on one end of which a presser foot is secured above a sewing station and a needle bar on one end of which a needle is secured for cooperatively engaging the sewing station, a force measuring system comprising: a transducer mounted on said presser bar for measuring forces applied to the presser bar during sewing; a transducer mounted on said needle bar for measuring forces applied to the needle bar during sewing; circuit means electrically connected to said first and second transducers for monitoring fabric feeding and stitch formation forces encountered by the presser bar and the needle bar during sewing; and computer means electrically connected to said circuit means for analyzing the forces measured by said first and second transducers.
Claim 14
Dependent Claim
18 words
In a sewing machine according to claim 11 wherein said computer means comprises a selectively programmed personal computer.
Claim 15
Dependent Claim
15 words
In a sewing machine according to claim 11 wherein said computer means comprises a microprocessor.
Claim 16
Independent Claim
158 words
A method for simultaneously measuring the force being applied to the presser bar and to the needle bar of a sewing machine in order to analyze material stitching and feeding performance of the machine, said sewing machine being provided with a force transducer on both the needle bar and the presser bar and an electrically connected circuit means and computer means for monitoring and analyzing the forces encountered by the presser bar and needle bar, the method comprising the steps of: simultaneously detecting the load changes applied to the presser bar and needle bar during operation of said sewing machine; converting the detected load changes at the presser bar and needle bar into signal data representing the forces simultaneously applied to the presser bar and needle bar, respectively; and analyzing said signal data representing the forces simultaneously applied to the presser bar and needle bar of said sewing machine to determine certain material stitching and feeding performance parameters.
Claim 17
Independent Claim
158 words
A method for simultaneously measuring the force being applied to the presser bar and to the needle bar of a sewing machine in order to analyze material stitching and feeding performance of the machine, said sewing machine being provided with a force transducer on both the needle bar and the presser bar and an electrically connected circuit means and computer means for monitoring and analyzing the forces encountered by the presser bar and needle bar, the method comprising the steps of: simultaneously detecting the load changes applied to the presser bar and needle bar during operation of said sewing machine; converting the detected load changes at the presser bar and needle bar into signal data representing the forces simultaneously applied to the presser bar and needle bar, respectively; and analyzing said signal data representing the forces simultaneously applied to the presser bar and needle bar of said sewing machine to determine certain material stitching and feeding performance parameters.
Claim 18
Dependent Claim
24 words
A method according to claim 14 wherein said force transducers serve to detect load changes and convert the detected load changes into signal data.
Claim 19
Dependent Claim
14 words
A method according to claim 15 wherein said force transducers comprise piezoelectric load washers.
Claim 20
Dependent Claim
45 words
A method according to claim 14 wherein the circuit means comprises an oscilloscope for monitoring said signal data and for simultaneously displaying a first waveform representing load changes applied to the presser bar and a second waveform representing load changes applied to the needle bar.
Claim 21
Dependent Claim
19 words
A method according to claim 17 wherein the circuit means includes a personal computer for analyzing said signal data.
Claim 22
Dependent Claim
20 words
A method according to claim 14 wherein the circuit means comprises a microprocessor for monitoring and analyzing said signal data.
Claim 23
Independent Claim
180 words
A method for simultaneously measuring the force being applied to the presser bar and to the needle bar of a sewing machine in order to analyze material stitching and feeding performance of the machine, said sewing machine being provided with a force transducer on both the needle bar and the presser bar and an electrically connected oscilloscope and computer for monitoring and analyzing the forces encountered by the presser bar and needle bar, the method comprising the steps of: simultaneously detecting the load changes applied to the presser bar and needle bar during operation of said sewing machine; converting the detected load changes at the presser bar and needle bar into signal data representing the forces simultaneously applied to the presser bar and needle bar, respectively; displaying said signal data in waveforms corresponding to forces applied to the presser bar and waveforms corresponding to forces applied to the needle bar; and analyzing said signal data representing the forces simultaneously applied to the presser bar and needle bar of said sewing machine to determine certain material stitching and feeding performance parameters.
Claim 24
Independent Claim
180 words
A method for simultaneously measuring the force being applied to the presser bar and to the needle bar of a sewing machine in order to analyze material stitching and feeding performance of the machine, said sewing machine being provided with a force transducer on both the needle bar and the presser bar and an electrically connected oscilloscope and computer for monitoring and analyzing the forces encountered by the presser bar and needle bar, the method comprising the steps of: simultaneously detecting the load changes applied to the presser bar and needle bar during operation of said sewing machine; converting the detected load changes at the presser bar and needle bar into signal data representing the forces simultaneously applied to the presser bar and needle bar, respectively; displaying said signal data in waveforms corresponding to forces applied to the presser bar and waveforms corresponding to forces applied to the needle bar; and analyzing said signal data representing the forces simultaneously applied to the presser bar and needle bar of said sewing machine to determine certain material stitching and feeding performance parameters.
References Cited (Backward Citations)
US3055326A
Cited
US3554025A
Cited
US4166423A
Cited
US4343249A
Cited
US4363281A
Cited
US4565143A
Cited
US4478092A
Cited
US4565140A
Cited
US4660481A
Cited
DE3540126A1
Cited
US4798152A
Cited
JPS6464279A
Cited
JPH02120883A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-09-25 | 1993-03-27 | 1993-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-25 | 1997-03-27 | 1997-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-25 | 2001-03-27 | 2001-09-26 | $7700.00 | Window Closed / Lapsed |