Patent US2621535A successfully refreshed from Google Patents.
US2621535A
Expired / Lapsed
US
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Safety hand brake for tractors
Assignee: Individual
•
Filing: 1950-05-01
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Granted: 1952-12-16
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Expires: 1970-05-01
Abstract
No abstract record available.
Inventors
- 👤 Joseph E Engels
- 👤 Thomas A Engels
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:18
CPC Classifications
B; B60; B60T; B60T7/00; B60T7/02; B60T7/08; B60T7/10; B60T7/102; B60T7/104; Y; Y10; Y10T; Y10T74/00; Y10T74/20; Y10T74/20207; Y10T74/20213; Y10T74/2022
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1509638A
Cited
US1621427A
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US1711929A
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US1801987A
Cited
US1833458A
Cited
US2423043A
Cited
US2555417A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-12-16 | 1956-06-16 | 1956-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-12-16 | 1960-06-16 | 1960-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-12-16 | 1964-06-16 | 1964-12-16 | $7700.00 | Window Closed / Lapsed |