Communications: electrical – Condition responsive indicating system – Specific condition
Patent
1993-10-08
1995-10-31
Peng, John K.
Communications: electrical
Condition responsive indicating system
Specific condition
340604, 340592, G08B 2100
Patent
active
054633770
ABSTRACT:
An apparatus for detecting the presence of a liquid in a region, including an electrically passive sensor adapted for contacting the liquid, and an electrically active detector. The sensor is a circuit with a pair of spaced-apart terminals connected to a switch that closes in the presence of the liquid. The detector carries an alternating current with a resonant frequency. When the sensor is placed in a region and liquid is present in the region, the circuit of the sensor is closed. By bringing the detector close to the sensor, an alternating current is induced in the sensor that will, in turn, alter the resonant frequency of the detector. The change in the resonant frequency is signaled by a transducer. The switch can operate by a change in conductivity of a material between the terminals of the sensor or by expansion of a liquid absorber that pushes the two terminals together, or by a change in the conductivity of the space between the terminals as a result of the presence of the liquid. The detector generates an audible or visible signal, or both, in response to the change in current.
REFERENCES:
patent: 4246575 (1981-01-01), Purtell et al.
patent: 4502044 (1985-02-01), Farris et al.
patent: 4598273 (1986-07-01), Bryan, Jr. et al.
patent: 4653491 (1987-03-01), Okada et al.
patent: 4754264 (1988-06-01), Okada et al.
patent: 5293149 (1994-03-01), Wilson et al.
Hands-On Electronics, Sep./Oct. 1986, p. 24, FIG. 36-5.
Dixon Harold M.
Mannaua Ashok
Moser William R.
Peng John K.
The United States of America as represented by the United States
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