| 摘要 |
PURPOSE:To supply fresh toner onto a sleeve at all times and to maintain stable development characteristics by releasing a toner layer on the sleeve from an attractive force from the sleeve by a magnetic pole for separation arranged in a toner hopper and separating it from the sleeve. CONSTITUTION:The toner on the sleeve 17 decreases in magnetic attractive force when passing through the gap formed of a separating magnet 19 and the sleeve 17. Namely, counter magnetic poles have the same polarity, so the attractive force becomes 0 where magnetic fields of both magnetic poles at the intermediate part balance with each other. Further, toner is attracted to nearby a collecting magnetic pole 20 as simulated with lines 21 of magnetic force produced by the separating magnet 19 to constitute a magnetic brush 22. The attractive force to the sleeve, therefore, decreases and the toner on the sleeve 17 is released temporarily from the sleeve by receiving the mechanical force of the magnetic brush 20, so that fresh toner particles from the toner hopper 18 stick on the sleeve one after another. Consequently, the development characteristics never become unstable owing to cohered toner sticking permanently on the sleeve. |
