Patent US4447721A successfully refreshed from Google Patents.
US2571920A
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US
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Variable-speed drive control for spinning frames
Assignee: Reeves Pulley Co
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Filing: 1949-11-12
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Granted: 1951-10-16
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Expires: 1969-11-12
Abstract
No abstract record available.
Inventors
- 👤 John S Michie
- 👤 Paul B Reeves
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:21
CPC Classifications
D; D01; D01H; D01H1/00; D01H1/14; D01H1/20; D01H1/32; F; F16; F16H; F16H9/00; F16H9/02; F16H9/04; F16H9/12; F16H9/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2096431A
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US2224369A
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US2094750A
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US2346868A
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US2277004A
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US2342941A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-10-15 | 1955-04-16 | 1955-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-10-15 | 1959-04-16 | 1959-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-10-15 | 1963-04-16 | 1963-10-16 | $7700.00 | Window Closed / Lapsed |