| 摘要 |
PURPOSE:To charge magnetic toner uniformly by providing a developing device with a supplementing sleeve and an adjacent stirring sleeve, each having a magnet, and a developing sleeve arranged between the stirring sleeve and the photoreceptor of a copying machine, and carrying the toner. CONSTITUTION:Magnetic toner 3 in a development tank 2 is stirred with an agitator 4 and fed upward with constant toner layer thickness through a gap between a doctor blade 5 and a supplementing sleeve 6 which has a surface opposed to the agitator 4 and a magnet 8 near it and turns at a speed V1 as shown by an arrow 7. A stirring sleeve 9 arranged close to the sleeve 6 is turned at a higher speed V2 than a speed V1 as shown by an arrow 12, around an incorporated magnet 11 turning as shown by an arrow 10 to thin a toner layer, which is fed through a scraper 13 to a developing sleeve 15 which has a magnet 17 facing to a photoreceptor 16 and turns as shown by an arrow 14. Thus, the toner 3 made into a constant thin layer is charged uniformly by being induced by the photoreceptor 16. Further, there is the enough gap between the doctor blade 5 and sleeve 6 and the toner 3 is never napped irregularly owing to dust and paper powder, achieving superior development. |
