Patent ID: 6552552
Filing Date: 2003-04-22
Classification: G01R

Abstract:
A capacitance type moisture sensor comprising:a sensor housing having an electrically-insulating wall, an outer surface of said electrically-insulating wall facing a space where amounts of water should be detected; a pair of electrodes disposed on said sensor housing such that at least one of said electrodes is formed on an inner surface of said electrically-insulating wall, and said electrodes are spaced from each other along said electrically-insulating wall, electric field developed between said electrodes being defined as a moisture detecting region; and a circuit unit including a capacitance detecting circuit for detecting a capacitance value between said electrodes, which changes in response to the amounts of water in said moisture detecting region, and an output circuit for providing an electrical signal corresponding to the amounts of water according to the capacitance value detected by said capacitance detecting circuit.