Electrically-driven brush

A toothbrush comprising:

• a handle at one end and a brush head fixed to the handle at the opposite end of the toothbrush;
• said brush head including a group of bristle holders disposed in a circle and each being rotatable about its respective axis;
• an electric motor disposed within the handle;
• and transmission means extending form said motor in the handle to said bristle holders in the brush head for rotating all said bristle holders about their respective rotary axes.

A brush comprising:

• a handle at one end and a brush head at the opposite end;
• said brush head including a group of bristle holders disposed in two substantially straight lines with each bristle holder being rotatable about its respective axis;
• an electric motor in the handle;
• and transmission means within the brush head and connected to said motor and to said bristle holders for rotating all said bristle holders about their respective rotary axes;
• said transmission means including a rotary lead screw coupled to said bristle holders to rotate them during the rotation of the lead screw;
• said bristle holders of the two lines being formed with threads meshing with the threads of said lead screw;
• said lead screw having alternating left-hand and right-hand threads to alternate the directions of rotations of adjacent bristle holders.