Patent US3320740A successfully refreshed from Google Patents.
US3320740A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Press
Assignee: Walker Manufacturing Co
•
Filing: 1965-07-02
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Granted: 1967-05-23
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Expires: 1985-07-02
Abstract
No abstract record available.
Inventors
- 👤 Clark J Hamkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:50
CPC Classifications
B; B21; B21J; B21J7/00; B21J7/20; B21J7/22; B21J7/24; B21J7/26; B30; B30B; B30B1/00; B30B1/002
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US588062A
Cited
US1597924A
Cited
US3012549A
Cited
US2898893A
Cited
US3042008A
Cited
US3213607A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-05-22 | 1970-11-21 | 1971-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-05-22 | 1974-11-21 | 1975-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-05-22 | 1978-11-21 | 1979-05-23 | $7700.00 | Window Closed / Lapsed |