Patent ID: 8459895

Claim:
A power transmission device that transmits a rotation power from a drive source to a driven object, the power transmission device comprising: a first rotation member and a second rotation member coaxially arranged to rotate in a circumference direction around a rotation axis relative to each other; and an impact absorber made of rubber and arranged between the first rotation member and the second rotation member to have elastic deformation in a twist direction centering on the rotation axis, wherein the first rotation member has a recess continuously extending in a direction inclined to the rotation axis from a first end to a second end, and a lock part extending in the circumference direction from the second end of the recess, the second rotation member has a projection configured to be engaged with the recess continuously from the first end of the recess to the second end of the recess, the projection being locked with the lock part when the projection moves to the lock part from the second end of the recess.