US2168680A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system for heating plants
Assignee: INTERNAT ENGINEERING CORP
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Filing: 1936-01-02
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Granted: 1939-08-08
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Expires: 1956-01-02
Abstract
No abstract record available.
Inventors
- 👤 Arnold W Nordgren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 18:51
CPC Classifications
G; G05; G05D; G05D23/00; G05D23/19; G05D23/275; G05D23/27535; G05D23/2754
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) | 1942-08-07 | 1943-02-06 | 1943-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-08-07 | 1947-02-06 | 1947-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-08-07 | 1951-02-06 | 1951-08-08 | $7700.00 | Window Closed / Lapsed |