| 摘要 |
PURPOSE:To carry a developer directly on the surface of a magnet roller and to simplify the structure by using a developer which has a <=10mum quantity average particle size and <=40emu/g saturation magnetization. CONSTITUTION:The magnet roller 9 holds the supplied developer 8 with a magnetic force and the developer is controlled by a conveyance amount control member 11 to a proper amount and conveyed. At this time, the developer 8 has a <=10mum quantity average particle size and <=40emu/g saturation magnetization. Then the leak magnetic flux of the magnet roller 9 is converged effectively on the developer 8 obtain high magnetic flux density and also increase its magnetic gradient. Consequently, even when a developer 8 of fine particle size is provided, the developer 8 can be carried only on the surface of the magnet roller 9 with a sufficient magnetic restriction force. Then the structure is simple, the man-hours from the manufacture to the assembly are small, and the low-cost developing device 7 is obtained. |
