Vorrichtung zum Erfassen einer vorbestimmten Bewegungsposition eines beweglichen Elementes

摘要

A position detecting device includes a ring gear that is disposed on an outer side of an output shaft of a motor and rotates with the rotation of the output shaft, fixed contact terminals fixed to a cover plate, and a rotary contact terminal provided on a ring gear. As the ring gear rotates, the fixed contact terminals and the rotary contact terminal are brought into contact with each other, thereby detecting a rotational position of the output shaft. The position detecting device further includes a clutch mechanism for preventing the rotation of the ring gear by more than a predetermined degree while permitting the rotation of the output shaft of the motor in the state of contact. Hence, even if the output shaft of the motor is rotated sufficiently, this state of contact is maintained.