PURPOSE: To provide a moisture detector high in safety by employing a hydrophilic polymer for a moisture detecting section.
CONSTITUTION: A plate body 1 formed with a dent section 2 in a recessed shape in cross section is made of polymer, and at least, the surface of the dent is composed of a hydrophilic polymer. In this place, an almido fiber string 3 connects the bottom section of the dent section 2 to an actuator section 6a making an action detecting switch 6 operate while being interlocked with a change in shape due to water absorption and swelling of hydrophilic polymer. When moisture is detected, the dent section 2 is altered in shape because it absorbs water so as to be swollen, the action switch 6 is actuated, so that the action switch informs person concerned of moisture detection. Since the aforesaid change in shape takes place momentarily at a time when the bending stress of the dent section exceeds its limit value, neither chaterring nor arc discharge takes place, so that a moisture detector high in safety can thereby be obtained. Besides, after the moisture detector has been dewatered, the detector is restored to an initial condition so as to allow each electrical contact is restored to a condition ready for reoperation.
INAGAKI KUNIHIRO
OKAMOTO HIROSHI
UNIV SHIZUOKA