US3671142A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid level control
Assignee: LUMENITE ELECTRONIC CO
•
Filing: 1970-06-22
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Granted: 1972-06-20
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Expires: 1990-06-22
Abstract
Abstract LIQUID LEVEL CONTROL OR INDICATOR CIRCUIT IN WHICH A RESISTANCE BRIDGE IS UNBALANCED BY CHANGE OF LIQUID LEVEL IN A CONTAINER. BRIDGE IS NORMALLY SLIGHTLY UNBALANCED, AND THE DEGREE OF THIS SLIGHT UNBALANCE MAY BE VARIABLE TO CHANGE THE SENSITIVITY. CHANGE IN LIQUID LEVEL SINIFICANTLY UNBALANCES THE BRIDGE TO BIAS A CONTROLLED RECTIFIER, THEREBY TRIGGERING ENERGIZATION OF A PUMP, VALVE, OR SIGNAL OR INDICATOR DEVICE.
Inventors
- 👤 Ronald V Calabrese
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:00
CPC Classifications
G; G01; G01F; G01F23/00; G01F23/22; G01F23/24; G01F23/241; G01F23/243; G05; G05D; G05D9/00; G05D9/12; Y; Y10; Y10T; Y10T137/00; Y10T137/7287; Y10T137/7306
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) | 1975-06-20 | 1975-12-20 | 1976-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-20 | 1979-12-20 | 1980-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-20 | 1983-12-20 | 1984-06-20 | $7700.00 | Window Closed / Lapsed |