| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a constitution whereby a rack and a pinion can be simply meshed with each other at a correct position in an image forming apparatus of a constitution which switches an LED head by a rack pinion mechanism between an adjacent position and an isolate position. <P>SOLUTION: The LED head 14 which forms an electrostatic latent image to a photosensitive drum is attached to a slide member 51. The slide member 51 is moved by a pinion gear 57 and the rack 59 between the adjacent position where the LED head 14 is made adjacent to the photosensitive drum and the isolate position where the LED head is isolated from the photosensitive drum. The pinion gear 57 has a plurality of teeth arranged in a circular arc. An inter-teeth pitch between the tooth 58e of the endmost and the next tooth 58 (end pitch) p1 is set larger than an inter-teeth pitch of the other teeth (normal pitch) p2 at both end sides in the peripheral direction of the pinion gear 57 (p1>p2). <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
