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Patent US3498141A successfully refreshed from Google Patents.
US3498141A
Expired / Lapsed
US
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Liquid level indicator in protective environment
Assignee: Illinois Tool Works Inc
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Filing: 1969-01-13
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Granted: 1970-03-03
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Expires: 1989-01-13
Abstract
No abstract record available.
Inventors
- 👤 John F Nelson
- 👤 Ougljesa J Poupitch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 12:20
CPC Classifications
G; G01; G01F; G01F23/00; G01F23/22; G01F23/28; G01F23/284; G01F23/292; G01F23/2921; G01F23/2922
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1191667A
Cited
US1381005A
Cited
US1969679A
Cited
US2145783A
Cited
US2510663A
Cited
US2678060A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-03-02 | 1973-09-01 | 1974-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-03-02 | 1977-09-01 | 1978-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-03-02 | 1981-09-01 | 1982-03-03 | $7700.00 | Window Closed / Lapsed |