| 摘要 |
PURPOSE:To obtain a developed image of invariably excellent picture quality stably for a long period by providing a hollow chamber where a magnetic carrier is charged previously. CONSTITUTION:The hollow chamber 7 where a constant amount of the magnetic carrier Ca is charged previously is formed on a front control plate 4, tufts height control plate 5, and partition plate 13, and this hollow chamber 7 is open to the outer peripheral surface of a developing sleeve 2 which is positioned at the upstream side of a development area A in a developer conveyance direction and above it. The constant amount of the magnetic carrier Ca is charged in this hollow chamber 7, but charged while mixed with a constant amount of insulating toner To. Consequently, the toner density of a magnetic developer is held constant and a developed image of invariably excellent picture quality is obtained for a long period. |
