developing device

Abstract

Abstract PURPOSE:To prevent a leak of magnetic particles from a magnetic particle constraining member by arranging a magnetic shield member on the downstream side of a developer holding member in the moving direction. CONSTITUTION:A magnetic fixed shaft 9 is provided as the magnetic shield member on the downstream side of a magnet 7 in a sleeve rotating direction. Lines of magnetic force generated by the magnet 7 on the downstream side in the sleeve rotating direction are directed to the magnetic fixed shaft 9 and do not appear on the surface of a sleeve 2, so that it seems that shield effect is obtained. The shield effect of this fixed shaft 9 prevents a leak of the magnetic field on the downstream side of a magnetic blade to the sleeve surface. Therefore, there is no magnetic field present on the sleeve surface on the downstream side of the blade, and magnetic particles are inhibited sufficiently from flowing out to the blade downstream side; the surface of a photosensitive drum is protected, the formation of black points in a developed image is prevented, and the need for operation such as the supplementation of magnetic particles is eliminated.

Inventors

• 👤 Hidemi Egami
• 👤 江上　秀己
• 👤 Takashi Saito
• 👤 敬 斉藤

Bibliographic Details