Patent ID: 6362469
Filing Date: 2002-03-26
Classification: B62D,G01D

Abstract:
A rotation detector for a multi-rotation body, comprising:a rotor member having a code plate of a rotary encoder and integrally rotating with the code plate, the rotor member being attached to the multi-rotation body to integrally rotate with the multi-rotation body; first detecting elements that detect a rough rotation angle of more than one revolution of the multi-rotation body in cooperation with the code plate; a rotary member arranged concentrically with a center of rotation of the rotor member, the rotary member having a driven gear along a rotation direction thereof; an intermediate gear engaged with the driven gear of the rotary member that intermittently transmits rotation of the rotor member to the rotary member; second detecting elements that detect an amount of rotation of the rotary member rotating in accordance with rotation of the intermediate gear, and that detect a precise rotation angle of more than one revolution of the rotation body; and a stator member enclosing the rotor member, the rotary member, the intermediate gear, and the first and second detecting elements, wherein the stator member includes a detection window through which an indicator that indicates a neutral rotation position of the rotary member is viewable from the outside of the stator member.