Tooth-brush with time switch - automatically actuated by temp. of mouth and/or hand for signal transmission

Cleaning of teeth should last at least 60 seconds for effective protection against decay etc. A time sensor is therefore provided in the toothbrush, which generates a signal after an effective cleaning period. The sensor responds to the temp. of the mouth and/or a hand for actuation of its operation. Pref. a plate (2) with a thermo-colour field is secured to the toothbrush, providing illumination in dependence of its warming up, i.e. the cleaning period. This plate may be secured to the head (1) containing the bristles. Alternately, it is secured to the inside of the handle. The sensor contains a thermostat, a transistor and a battery, all housed in a part of the toothbrush. It may generate an optical signal under the thermostat control. The battery may be coupled to a solar energy powered generator.