Patent US3564531A successfully refreshed from Google Patents.
US3564531A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Blade angle control device
Assignee: Individual
•
Filing: 1967-07-24
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Granted: 1971-02-16
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Expires: 1987-07-24
Abstract
Abstract A BODY OF MERCURY, THE MOVEMENT OF WHICH IS DAMPENED BY BAFFLES, ESTABLISHES A CONDUCTIVE PATH BETWEEN CONTACTS WITHIN A CHAMBER THE POSITION OF WHICH REFLECTS TILTING OF A GRADING BLADE OF AUTOMATICALLY CORRECT THE POSITION OF THE BLADE. THE SENSITIVITY OF THE DEVICE IS VARIED BY ADJUSTING THE POSITION OF AN ELEMENT PARTIALLY SUBMERGED IN THE MERCURY.
Inventors
- 👤 Luther B Burgin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:33
CPC Classifications
H; H01; H01H; H01H29/00; H01H29/20
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-02-15 | 1974-08-17 | 1975-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-15 | 1978-08-17 | 1979-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-15 | 1982-08-17 | 1983-02-16 | $7700.00 | Window Closed / Lapsed |