Patent US1639411A successfully refreshed from Google Patents.
US1639411A
Expired / Lapsed
US
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Receiver for heat signs
Assignee: Carl Zeiss SMT GmbH
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Filing: 1921-08-13
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Granted: 1927-08-16
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Expires: 1941-08-13
Abstract
No abstract record available.
Inventors
- 👤 Mechau Robert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:48
CPC Classifications
G; G01; G01K; G01K1/00; G01K1/20
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) | 1930-08-15 | 1931-02-14 | 1931-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1934-08-15 | 1935-02-14 | 1935-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1938-08-15 | 1939-02-14 | 1939-08-16 | $7700.00 | Window Closed / Lapsed |