US2970023A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Piston ring
Assignee: Perfect Circle Corp
•
Filing: 1958-02-24
•
Granted: 1961-01-31
•
Expires: 1978-02-24
Abstract
No abstract record available.
Inventors
- 👤 Thompson Bert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:43
CPC Classifications
F; F16; F16J; F16J9/00; F16J9/12; F16J9/20
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1964-01-31 | 1964-08-01 | 1965-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-01-31 | 1968-08-01 | 1969-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-01-31 | 1972-08-01 | 1973-01-31 | $7700.00 | Window Closed / Lapsed |