| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress increase in the rotational load of a driving-force transmitting member constituted by integrally molding a drive input part and a drive output part with a rotary shaft part due to thermal expansion when using such a driving-force transmitting member. <P>SOLUTION: A photosensitive-element gear 133 rotatably supported through a large-diameter boss 133b and a small-diameter boss 133c to side plates 110a and 110b is formed of a material having a linear expansion coefficient larger than that of a sleeve bearing member 134b, and a difference Δx1 between the inner radius R1 of the sleeve bearing member and the outer radius r1 of the rotary shaft part in the photosensitive-element gear at a reference temperature satisfies expression (1) Δx1>r1×Δt×a-R1×Δt×b. Provided that Δt is maximum amount of temperature change of the driving-force transmitting device relative to the reference temperature, a is linear expansion coefficient of the sleeve bearing member, and b is linear expansion coefficient of the driving-force transmitting member. <P>COPYRIGHT: (C)2009,JPO&INPIT |
