To provide a compact electric motor-driven device suppressing an excess pressure rise inside a body case.
This electric toothbrush includes the body case 20 including an intermediate case and a grip case 60 which are independently formed and are combined with each other. The body case 20 is formed with a facing part 37 wherein the outer face of the intermediate case and the inner face of the grip case 60 face to each other. A grip side seal 24 sealing the facing part 37 is provided between the outer face of the intermediate case and the inner face of the grip case 60. When the pressure inside the body case 20 is higher than a pressure outside the body case 20, the grip side seal 24 is deformed based on a difference between the pressure inside the body case 20 and the pressure outside the body case 20. At this time, the inside of the body case 20 and the outside of the body case communicate with each other. Thereby, the pressure inside the body case 20 is reduced.
WANG WEI
KITAMURA YOSHIHIRO
| JPH09168554A | 1997-06-30 | |||
| JPS5921574U | 1984-02-09 |
Makoto Onda