FORCE SENSOR PROVIDING CONTINUOUS FEEDBACK FOR A RESONANT DRIVE TOOTHBRUSH USING A HALL SENSOR

摘要

The power toothbrush includes a brushhead arm (36) and a brush element (38) at a distal end thereof. A V-spring assembly (14) converts the movement of a power drive assembly in a back-and-forth movement. A mounting member (55) at the rear end of the V-spring assembly provides a base for a magnet (56). The back end of the V-spring assembly is displaced in accordance with pressure applied to the brush member. A Hall effect sensor (58) is mounted within the changing magnetic field produced by the magnet as the rear end of the V-spring assembly is displaced due to pressure on the brushhead. A processor (65) is responsive to the output from the Hall sensor and provides an indication when the pressure exceeds a threshold value.