US2749570A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dual action lift spring
Assignee: Individual
•
Filing: 1954-03-17
•
Granted: 1956-06-12
•
Expires: 1974-03-17
Abstract
No abstract record available.
Inventors
- 👤 Clayton W Alder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 11:28
CPC Classifications
E; E05; E05D; E05D13/00; E05D13/10; E05D13/12; E05D13/1253; E05D13/1261; E05Y; E05Y2900/00; E05Y2900/10; E05Y2900/106
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) | 1959-06-12 | 1959-12-12 | 1960-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-06-12 | 1963-12-12 | 1964-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-06-12 | 1967-12-12 | 1968-06-12 | $7700.00 | Window Closed / Lapsed |