| 摘要 |
1,134,158. Electric toothbrushes. BRAUN A.G. 16 May, 1967 [21 May, 1966], No. 22742/67. Heading A4K. In order to adjust the amplitude of the brushing stroke of an electric toothbrush the engagement between co-operating elements in the transmission from a crank drive to the brush shaft 5, (30) can be varied during use of the brush. In some forms (Figs. 4-6, not shown), the brush shaft 30, 36) is operated as a single or two-armed lever of variable mechanical advantage. As shown, a pin 21 is concentrically mounted on the spindle 18 of an electric motor 4 and rides in a groove 22 of a rocker arm 23 of an axle 24, supporting shaft 5. On moving plunger 16 from its dotted line position, the circuit of the motor 4 is completed through sliding contact of the end of wire 12 with contact spring 13 and pin 21 runs in the outer end of groove 22. As the pin 21 is moved towards the inner end of groove 22, by further depressing plunger 16, the amplitude of the brush stroke is increased. Springs 14, 15 return motor 4 to its original position, when plunger 16 is released. |
