Patent US2420444A successfully refreshed from Google Patents.
US2420444A
Expired / Lapsed
US
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Intermittent mechanism
Assignee: DE VRY Corp
•
Filing: 1944-08-29
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Granted: 1947-05-13
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Expires: 1964-08-29
Abstract
No abstract record available.
Inventors
- 👤 Thomas I Ress
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:36
CPC Classifications
G; G03; G03B; G03B1/00; G03B1/18; G03B1/20; G03B1/22; Y; Y10; Y10T; Y10T74/00; Y10T74/15; Y10T74/1503; Y10T74/1508; Y10T74/1518; Y10T74/1523
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1716463A
Cited
DE571422C
Cited
GB232186A
Cited
GB227362A
Cited
US1871335A
Cited
US2029930A
Cited
US2148493A
Cited
US2152624A
Cited
US2200342A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-05-12 | 1950-11-11 | 1951-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-05-12 | 1954-11-11 | 1955-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-05-12 | 1958-11-11 | 1959-05-13 | $7700.00 | Window Closed / Lapsed |