| 摘要 |
<P>PROBLEM TO BE SOLVED: To stably obtain an excellent image for a long period by a developing device equipped with a toner carrier carrying toner to a development area and a toner supply roller supplying the toner to the toner carrier. <P>SOLUTION: This developing device is equipped with the toner carrier 11 which carries the nonmagnetic toner to the development area facing an image carrier P and the toner supply roller 15 which supplies the toner to the toner carrier; and a toner sending member 20 provided at the outer periphery of a rotary shaft 21 with screw type carrying blades 22a and 22b which carry the toner from both axial end parts to the center part or the center part to both the end parts and are different in direction is provided opposite the toner supply roller, and 9000≤(Db2-Da2)×p×w≤185000 holds, where Da is the diameter (mm) of the rotary shaft of the toner sending member, (p) is the mean pitch (mm) of the carrying blades, and (w) is the rotational frequency (r.p.m.). <P>COPYRIGHT: (C)2005,JPO&NCIPI |
