Electric tooth-brush with variable brushing frequency - has adjustment control provided as disc fitted to rear end of tooth-brush housing

摘要

A manual control adjusts the supply current fed to the operating motor. It comprises a rotary setting wheel (4) fitted to the rear end of the toothbrush housing (1) forming the handle, with a radial slot (12) into which the end of an eccentric (11) fits. The eccentric (11) projects from a disc (10) attached to the setting shaft (9) of a rotary potentiometer (8) for varying the motor current. Pref. the setting wheel (4) has a peripheral lip (5) which fits over the outer edge of the toothbrush housing (1) so as to form a rotary bearing for the setting wheel (4). The latter has a semicircular slot coaxial to its axis through which the electrical supply lead (13) projects. The rotary potentiometer is pref. contained in a dished carrier (2) open on the side which faces inwards and forming a water-tight fit with the housing (1). The brush operating frequency can be adjusted during operation.