US1777356A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat-interchange apparatus
Assignee: EMPIRE GAS AND FUEL Co
•
Filing: 1927-05-17
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Granted: 1930-10-07
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Expires: 1947-05-17
Abstract
No abstract record available.
Inventors
- 👤 James P Fisher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:30
CPC Classifications
F; F28; F28F; F28F9/00; F28F9/007; F28F9/013; F28F9/0137; Y; Y10; Y10S; Y10S165/00; Y10S165/355; Y10S165/40; Y10S165/401; Y10S165/405; Y10S165/406
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) | 1933-10-06 | 1934-04-07 | 1934-10-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1937-10-06 | 1938-04-07 | 1938-10-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1941-10-06 | 1942-04-07 | 1942-10-07 | $7700.00 | Window Closed / Lapsed |