| 摘要 |
The present invention is related to a pulley structure that is provided with a tubular first rotating body around which a belt is wound, a second rotating body provided inside the first rotating body so as to be rotatable relative to said first rotating body, and a torsion coil spring which is housed in the space between the first rotating body and second rotating body. The torsion coil spring has: at one end, an end region in which the outer peripheral surface makes contact with either the first rotating body or second rotating body through a self-elastic restoring force in the large-diameter direction of the torsion coil spring in a state in which the pulley structure is stopped; at the other end, another end region in which the inner circumferential surface makes contact with the other rotating body in a state in which the pulley structure is stopped; and a center region. In cases where the torsion coil spring twists in the large-diameter direction due to the relative rotations of the two rotating bodies, the inner circumferential surface of at least a portion of the other end region of the torsion coil spring in the circumferential direction is separated from the other rotating body. |
