US3738296A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photoelectric relative motion detector
Assignee: USM Corp
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Filing: 1971-09-21
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Granted: 1973-06-12
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Expires: 1991-09-21
Abstract
Abstract A Photoelectric Relative Motion Detector in which a light source and a photoelectric device are mounted on a plate adjacent one side of an object having portions varying in light reflectivity spaced along a path of relative motion between the detector and the object. The plate shields portions of the object along the path from ambient light and shields electrical leads connecting the device to external circuits from extraneous electrical signals.
Inventors
- 👤 R Karcher
- 👤 Kenzie F Mac
- 👤 R Brophy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:01
CPC Classifications
D; D05; D05B; D05B59/00; D05B59/02
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
120 words
A detector for use on a sewing machine having a rotating bobbin wound with thread, the bobbin having a spot on a surface differing in light reflectivity from the remaining bobbin surface, wherein the detector comprises: a plate mounted adjacent the spotted surface of the bobbin to shield the bobbin surface from ambient light along a path of relative motion between the rotating bobbin and the plate; a photoelectric device and a light source mounted on the plate to reflect source light from the surface to the device along the path of motion; external circuits; and means within the plate electrically connecting the device to the external circuits for electrically shielding and physically supporting the connecting means within the plate.
Claim 2
Dependent Claim
120 words
A detector for use on a sewing machine having a rotating bobbin wound with thread, the bobbin having a spot on a surface differing in light reflectivity from the remaining bobbin surface, wherein the detector comprises: a plate mounted adjacent the spotted surface of the bobbin to shield the bobbin surface from ambient light along a path of relative motion between the rotating bobbin and the plate; a photoelectric device and a light source mounted on the plate to reflect source light from the surface to the device along the path of motion; external circuits; and means within the plate electrically connecting the device to the external circuits for electrically shielding and physically supporting the connecting means within the plate.
Claim 3
Dependent Claim
31 words
A detector as in claim 1 wherein the external circuits comprise a counter and means responsive to the counter for stopping the machine when the counter coincides with a preselected number.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-11 | 1976-12-11 | 1977-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-11 | 1980-12-11 | 1981-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-11 | 1984-12-11 | 1985-06-12 | $7700.00 | Window Closed / Lapsed |