US2220581A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spring shield
Assignee: Transit Research Corp
•
Filing: 1938-08-16
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Granted: 1940-11-05
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Expires: 1958-08-16
Abstract
No abstract record available.
Inventors
- 👤 Emil H Piron
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:56
CPC Classifications
F; F16; F16F; F16F1/00; F16F1/36; F16F1/38; B; B60; B60G; B60G11/00; B60G11/22
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) | 1943-11-05 | 1944-05-06 | 1944-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-11-05 | 1948-05-06 | 1948-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-11-05 | 1952-05-06 | 1952-11-05 | $7700.00 | Window Closed / Lapsed |