Leak detector comprising a self-heated thermistor control circuit
US7607823B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 2, 2005 |
| Grant date | Oct 27, 2009 |
| Priority date | — |
| Expiry date | Mar 2, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01M3/002
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system and method for detecting leaks includes a sensing circuit including a first thermistor device adapted to detected a leak upon contact with a liquid, and, a second thermistor device functioning as a reference device. The first and second thermistor devices are driven with a current such that both devices operate in self-heated mode at a temperature above an ambient temperature. A control system controls a drive circuit for maintaining a constant application of power through both devices in response to a voltage monitored at a reference point in the sensing circuit including the reference thermistor. The voltage at a reference point in a portion of the sensing circuit including the first thermistor device is additionally monitored and compared with the voltage at the reference point in the sensing circuit including the second thermistor device. A leak condition is determined on the basis of a comparison result of the ambient temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.