US3497677A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric heater unit for liquid reservoirs
Assignee: Elevator Equipment Co
•
Filing: 1968-03-04
•
Granted: 1970-02-24
•
Expires: 1988-03-04
Abstract
No abstract record available.
Inventors
- 👤 Roy W Blain
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:49
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/40; H05B3/42; H05B3/48; H05B3/50
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2735922A
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US1881881A
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US2569250A
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US2789201A
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US3085145A
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US3111574A
Cited
US3166666A
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US3272965A
Cited
US3277277A
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US3371188A
Cited
US3399295A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-02-23 | 1973-08-25 | 1974-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-02-23 | 1977-08-25 | 1978-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-02-23 | 1981-08-25 | 1982-02-24 | $7700.00 | Window Closed / Lapsed |