Patent ID: 6918835

Claim:
A power transmission system for transmitting torque from a driving unit to a driven unit, the system comprising: a first rotating member rotated by the driving unit; a second rotating member connected to the driven unit; a torque limiter that transmits torque from the first rotating member to the second rotating member, wherein the torque limiter is partially broken to interrupt transmitting the torque when the torque transmitted to the driven unit exceeds a predetermined value; a damper that is formed of an elastically deformable member and disposed in a passage through which the torque between the first and the second rotating members is transmitted; and a cover that is hooked to be fixed with at least one of the first and the second rotating members to inhibit the damper from being displaced in a rotation axis direction of the first rotating member, wherein the cover includes a first-step protruding portion and a second-step protruding portion, wherein by using the first-step protruding portion the cover is hooked in a first state while by using the second-step protruding portion the cover is hooked in a second state, and wherein a clearance between the cover and the damper in the first state is narrower than a clearance between the cover and the damper in the second state.