Ultrasonic vibratory tooth-brush - has casing holding elongate piezoelectric member to which alternating signals are applied so inducing longitudinal vibrations

摘要

The toothbrush comprises an elongated piezoelectric member with a pair of contacting surfaces between the respective ends. A brush between extends from one end of the elongated member. A casing is of a length at least equal to the piezoelectric member and has an elongated bore adapted to receive it. Alternating electrical signals are supplied to a contact to establish an alternating field for transmission from the contact to the piezoelectric member. Mechanical vibration at the frequency of the alternating signals are induced in the elongated member and the brush member.