| 摘要 |
A power toothbrush has a brushhead mounted at one end thereof, the brushhead including a base mounting element for bristles which extend from one surface thereof. Extending from the opposing surface of the base mounting element is a pressure contact member. A substantially rigid brushhead shield extends along and is adjacent to the opposing surface of the brushhead. The brushhead has a hinge-like portion which permits the brushhead to move or swivel in response to pressure being placed on the brushhead, while the brushhead is moving back and forth at its operating frequency of its normal brushing action at over 150 Hz. Thin electrical switch contacts, which are part of an electrical circuit, are positioned on the brush shield, spaced from the contact member on the brushhead. When sufficient pressure is applied against the brushhead, the brushhead moves sufficiently about the hinge, while also continuing to move in normal action that the pressure contact member comes into contact with and then closes the switch contacts, closing the electrical circuit and resulting in a visual indication that the brushhead pressure has exceeded the maximum limit for desirable brushing pressure. |
