Patent US3531216A successfully refreshed from Google Patents.
US3531216A
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Shaft attaching means for pump impeller
Assignee: Allis Chalmers Pump Inc
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Filing: 1968-12-23
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Granted: 1970-09-29
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Expires: 1988-12-23
Abstract
No abstract record available.
Inventors
- 👤 Thomas R Callahan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:25
CPC Classifications
F; F16; F16D; F16D1/00; F16D1/06; F16D1/08; F16D1/09; F16D1/093; F16D1/095; F04; F04D; F04D29/00; F04D29/18; F04D29/20; Y; Y10; Y10T; Y10T403/00; Y10T403/70; Y10T403/7047; Y10T403/7051; Y10T403/7052; Y10T403/7056; Y10T403/7058
Claims Analysis
Total Claims: 0
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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) | 1973-09-28 | 1974-03-30 | 1974-09-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-09-28 | 1978-03-30 | 1978-09-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-09-28 | 1982-03-30 | 1982-09-29 | $7700.00 | Window Closed / Lapsed |