US2987022A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Collapsible back-up ring
Assignee: Grinnell Corp
•
Filing: 1956-09-26
•
Granted: 1961-06-06
•
Expires: 1976-09-26
Abstract
No abstract record available.
Inventors
- 👤 Helmut J Thielsch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:12
CPC Classifications
B; B23; B23K; B23K9/00; B23K9/02; B23K9/035
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1922324A
Cited
US1980419A
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US2214899A
Cited
US2226078A
Cited
US2321308A
Cited
US2429053A
Cited
US2694376A
Cited
FR1090052A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-06-05 | 1964-12-05 | 1965-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-06-05 | 1968-12-05 | 1969-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-06-05 | 1972-12-05 | 1973-06-06 | $7700.00 | Window Closed / Lapsed |