| 摘要 |
PROBLEM TO BE SOLVED: To provide a power transmission mechanism having no risk of poor meshing of a planetary gear with a cam gear and surely executing drive control.SOLUTION: This power transmission device includes: a cam gear which is rotated in one direction with drive force from a drive source transmitted by meshing of the planetary gear and of which rotation is stopped by release of meshing of the planetary gear; a driven member including a follower abutting on a circumferential surface cam formed on the cam gear, driven according to rotation of the cam gear, and giving assist torque in a rotation direction different from rotation torque by a drive source with respect to the cam gear; and a brake mechanism giving the cam gear load torque in a reverse rotation direction canceling assist torque by the driven member. |
