| 摘要 |
PURPOSE:To prevent ground fogging, a sweep trace, and a toner scatter effective ly by providing a perforated electrode which has many apertures with a specific diameter at the opening part of a developing device and depositing only toner particles. CONSTITUTION:The holed electrode plate 16 as a mesh body made of conductive metal having many fine apertures is provided at the opening 15 of the developing device and applied with a specific voltage. Then, the diameter of said apertures is larger than toner particle size and smaller than carrier particles size, e.g. the diameter of a 250-mesh net body. In this constitution, a magnetic brush is rubbed against the electrode plate 16 through the rotation of a nonmagnetic sleeve 12 and given an electrostatic charge, and only toner particles are deposited to perform development. Consequently, fogging is reduced, a sleeve 12 is rotated at a low speed, and a sweep trace and a toner scatter are prevented effectively. |
