| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a developing device that uses a two-component developer for defining the magnetic force of the developer carrier and the conditions of developer control members so that the developer carrier can carry uniform and proper amount of developer in the longitudinal direction, and convey the developers to a developing area. <P>SOLUTION: The developing device includes a first stirring screw 53 for stirring and transporting the two-component developer; a development sleeve 51 for containing a magnetic field generating means that forms a plurality of magnetic poles; and a doctor blade 52 for regulating the volume of the two-component developers on the development sleeve. The magnetic flux density in the normal direction of a developing agent pumping pole of the magnetic field generating means, contained in the development sleeve (P5 pole), is ≥75 mT and ≤95 mT. The doctor blade is supported to a developing device casing 56 at both ends thereof in the longitudinal direction so that the tip surface of a member, formed by applying one-time bending to a metal board member, is arranged facing the surface of the development sleeve, and the center of the tip surface in the longitudinal direction is of a concave shape, having straightness difference of 0.02-0.08 mm, with respect to both ends. <P>COPYRIGHT: (C)2007,JPO&INPIT |
