Patent ID: 8494414

Claim:
A drive device comprising: a drive source; a rotatable member gear, fixed on a rotation shaft of a rotatable member, for being rotated by transmitting thereto a driving force from said driving source; a follower gear, including a pair of gears which are coaxially disposed with each other and are rotatable at the same rotational speed by rotation of said rotatable member gear and including urging means for urging the pair of gears in rotational directions opposite from each other, for being rotated at the rotational speed higher than that of said rotatable member gear; a rotation detecting device for detecting rotation of said follower gear, wherein the rotation detecting device includes a flag rotatable together with said follower gear and provided coaxially with said follower gear and includes a detecting portion for detecting passing of the flag; and a driving source control portion for controlling said driving source on the basis of a detection result of the rotation detecting device.