| 摘要 |
<P>PROBLEM TO BE SOLVED: To engage a rotated developing unit with a gear for transmitting a drive force in a stage earlier than arrival of the rotated developing unit at a drive position and to suppress generation of noise, in a developing device and an image forming apparatus. <P>SOLUTION: The developing device includes a drive force transmitting member including a cam receiving roll energized toward a cam surface and pressed against the cam surface by the energization and a second gear energized together with the cam receiving roll and engaged with the first gear of the developing unit rotated to a position facing an image carrier on which a latent image to be developed is formed, of a plurality of developing units, to transmit the drive force to the first gear. The cam receiving roll is moved in a direction where the cam receiving roll is temporarily away from a rotation shaft and then, moved in a direction where the cam receiving roll gets closer to the rotation shaft, as the cam surface gets closer to a drive position where the first gear receives the drive force from the second gear, so that the first gear is started to engage with the second gear, before the first gear reaches the drive position. The cam surface is made into a curved surface having a curvature smaller than that of the cam receiving roll. <P>COPYRIGHT: (C)2012,JPO&INPIT |
