Developing device

摘要

A movable frame is mounted on a stationary frame so as to be reciprocatingly moved in a predetermined direction by a moving means. The movable frame is equipped with a plurality of developing mechanisms which may be selectively located at a developing position by the motion of the movable frame to carry out multi-color developing. The developing mechanisms are urged toward a rotary drum. In order to prevent the developing agent from scattering, side sealing pieces are provided near the non-developing operation region on both sides of a sleeve member in a magnetic brush mechanism of each developing mechanism. A toner container unit including toner containers and toner feeding means is rotatably supported by the stationary frame. The toner feeding means includes a extensible and contractible means which is detachably coupled to the developing mechanism. The toner container unit is selectively brought to a predetermined fixed position relative to the developing mechanism and to a predetermined retracted position turned in a direction to separate away from the developing mechanism.