| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an electric toothbrush having an eccentric shaft with variable resonant frequencies and vibration amplitude. <P>SOLUTION: The electric toothbrush 1 comprises a motor 23, an eccentric shaft 100 fixed at one end to a rotary shaft 23a of the motor 23, and a stem 3 having a bearing 31 for supporting the other end of the eccentric shaft 100, the stem 31 serving as a vibration transmission component for transmitting the vibration generated as the eccentric shaft 100 rotates to a brush portion 41, wherein the eccentric shaft 100 is configured such that the center of gravity thereof is movable in the direction that causes the distance to the axial center to change and/or the axial direction. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
