Patent US3020720A successfully refreshed from Google Patents.
US3020720A
Expired / Lapsed
US
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Method and means for producing hydraulic vibrations
Assignee: Individual
•
Filing: 1957-02-20
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Granted: 1962-02-13
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Expires: 1977-02-20
Abstract
No abstract record available.
Inventors
- 👤 Albert K Spalding
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:48
CPC Classifications
B; B06; B06B; B06B1/00; B06B1/20; E; E04; E04G; E04G21/00; E04G21/02; E04G21/06; E04G21/08; E21; E21B; E21B28/00; E21B43/00; E21B43/003; F; F15; F15B; F15B21/00; F15B21/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2090575A
Cited
US2080727A
Cited
US2215888A
Cited
FR47185E
Cited
US2270586A
Cited
FR835760A
Cited
US2187088A
Cited
US2298252A
Cited
US2447312A
Cited
US2581303A
Cited
US2472568A
Cited
US2597505A
Cited
US2520833A
Cited
US2649843A
Cited
US2687189A
Cited
US2655903A
Cited
US2767689A
Cited
US2763472A
Cited
US2773482A
Cited
US2797666A
Cited
US2869468A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-02-12 | 1965-08-14 | 1966-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-02-12 | 1969-08-14 | 1970-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-02-12 | 1973-08-14 | 1974-02-13 | $7700.00 | Window Closed / Lapsed |