PROBLEM TO BE SOLVED: To provide an electric toothbrush which allows vibration of bristle tip portions of bristles to easily reach narrow portions of teeth and gums, and which can improve a brushing effect and a massage effect in these narrow portions.SOLUTION: An electric toothbrush 10 includes: a body part 13 in which a rotary motor 11 in which an eccentric weight 12 is provided at a rotary shaft 11a is accommodated and a brush part 20 which includes a brush head part 21 and a neck part 22. At the brush head part 21, a plurality of bristle bundles 23a, 23b which are formed by bundling a plurality of bristles 24 are implanted, and the bristles 24 are taper bristles including taper-shaped portions. The brush head part 21 is set in such a manner that, when the rotary motor 11 is driven, the amplitude of the vibration in the bristle tip direction of the bristle bundles 23a, 23b is larger than the amplitude of the vibration in the width direction along an implanting surface 21a of the bristle bundles 23a, 23b.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2016,JPO&INPIT【課題】ブリッスルの毛先部分の振動を歯や歯茎の狭い部分に届き易くして、これらの狭い部分の刷掃効果やマッサージ効果を向上できる電動歯ブラシを提供する。【解決手段】回転軸11aに偏心錘12が設けられた回転モータ11が収容された本体部13と、ブラシヘッド部21と首部22とを含むブラシ部20とを具備する電動歯ブラシ10であって、ブラシヘッド部21には、複数のブリッスル24を束ねてなる毛束23a,23bが複数植毛されており、ブリッスル24は、テーパー形状部分を備えるテーパーブリッスルとなっている。回転モータ11を駆動させた際に、ブラシヘッド部21は、毛束23a,23bの植毛面21aに沿った幅方向の振動の振幅よりも、毛束23a,23bの毛先方向の振動の振幅の方が大きくなるように設定されている。【選択図】図1
