Patent US2247981A successfully refreshed from Google Patents.
US2247981A
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US
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Method of forming lock washers
Assignee: Philadelphia Steel and Wire Corp
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Filing: 1940-02-02
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Granted: 1941-07-01
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Expires: 1960-02-02
Abstract
No abstract record available.
Inventors
- 👤 Chandler C Washer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:22
CPC Classifications
B; B21; B21D; B21D53/00; B21D53/16; B21D53/20; Y; Y10; Y10S; Y10S411/00; Y10S411/955; Y10S411/956; Y10S411/957; Y10S411/958
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) | 1944-06-30 | 1944-12-30 | 1945-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-06-30 | 1948-12-30 | 1949-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-06-30 | 1952-12-30 | 1953-07-01 | $7700.00 | Window Closed / Lapsed |