USH652H
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sensor for detection of liquid spills on surfaces
Assignee: United States Department of Energy
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Filing: 1988-08-17
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Granted: 1989-07-04
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Expires: 2008-08-17
Abstract
Abstract A surface liquid detector is disclosed for detecting liquids spilled on surfaces such as floors. A temperature-sensitive thermistor probe is used in a bridge circuit to detect the change in resistance in the thermistor due to the change in thermal conductivity that occurs when a liquid contacts the probe. The device is characterized by the ability to detect either conductive or nonconductive liquids, such as water or oil spills.
Inventors
- 👤 Brent C. Davis
- 👤 Tom M. Gayle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:37
CPC Classifications
G; G08; G08B; G08B21/00; G08B21/18; G08B21/20; G01; G01F; G01F23/00; G01F23/22; G01F23/24; G01F23/246; G01F23/247; G01M; G01M3/00; G01M3/002
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
137 words
A liquid spill detector for detecting the presence of a liquid on a monitored surface, comprising: a probe mounting assembly including a temperature-sensitive thermistor sensing probe whose resistance changes in inverse proportion to the exposed temperature and means for mounting said probe in a position to be placed in contact with a liquid present on said monitored surface; a detection circuit means coupled with said sensing probe for generating an alarm signal in responsive to a substantial change in the resistance of said thermistor sensing probe due to a corresponding change in temperature produced by a change in thermal conductivity when contacted by a spilled liquid; and an alarm circuit means responsive to said alarm signal generated by said detection circuit means for generating an indication of an alarm condition upon the detection of said spilled liquid.
Claim 2
Dependent Claim
137 words
A liquid spill detector for detecting the presence of a liquid on a monitored surface, comprising: a probe mounting assembly including a temperature-sensitive thermistor sensing probe whose resistance changes in inverse proportion to the exposed temperature and means for mounting said probe in a position to be placed in contact with a liquid present on said monitored surface; a detection circuit means coupled with said sensing probe for generating an alarm signal in responsive to a substantial change in the resistance of said thermistor sensing probe due to a corresponding change in temperature produced by a change in thermal conductivity when contacted by a spilled liquid; and an alarm circuit means responsive to said alarm signal generated by said detection circuit means for generating an indication of an alarm condition upon the detection of said spilled liquid.
References Cited (Backward Citations)
US4037427A
Cited
US4413255A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-03 | 1993-01-02 | 1993-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-03 | 1997-01-02 | 1997-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-03 | 2001-01-02 | 2001-07-04 | $7700.00 | Window Closed / Lapsed |