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US2904159A
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Proportional spacing mechanism for typewriters
Assignee: Individual
•
Filing: 1955-11-04
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Granted: 1959-09-15
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Expires: 1975-11-04
Abstract
No abstract record available.
Inventors
- 👤 Smathers James Fields
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:23
CPC Classifications
B; B41; B41J; B41J19/00; B41J19/18; B41J19/20; B41J19/32
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US585235A
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US1837898A
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US2111410A
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US2211911A
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US2258116A
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US2303878A
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US2581200A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-09-14 | 1963-03-16 | 1963-09-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-09-14 | 1967-03-16 | 1967-09-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-09-14 | 1971-03-16 | 1971-09-15 | $7700.00 | Window Closed / Lapsed |