DEVELOPING DEVICE AND IMAGE FORMING APPARATUS

摘要

A developing device forms an image by developing an electrostatic latent image on a photoreceptor rotating about a rotation axis. The developing device includes a housing having an opening opposite the photoreceptor, a developing sleeve disposed inside the housing, a magnetic body disposed in a central portion of the developing sleeve and not in no-magnet portions thereof at both sides of the central portion, and seal members supported by the housing. Each of the seal members shields either one of portions of the photoreceptor that are located opposite the no-magnet portions and is in surface contact with either one of end portions of the photoreceptor farther from a center of the photoreceptor than the no-magnet portions. Each of the seal members includes, at an end thereof closer to the center of the photoreceptor than the other end thereof, a non-contact portion that is not in contact with the photoreceptor.

主权项

1. A developing device for forming an image by developing, using a developer, an electrostatic latent image on a photoreceptor rotating about a rotation axis, the developing device comprising:
a housing having an opening being located opposite the photoreceptor, the opening exposing therethrough a central portion of the photoreceptor that is located at the center of the photoreceptor in a direction along the rotation axis; a developing sleeve rotatably disposed inside the housing so as to face the central portion of the photoreceptor, the developing sleeve consisting of a central portion that is located at the center of the developing sleeve and end portions that are located at both sides of the central portion in the direction along the rotation axis; a magnetic body disposed inside the central portion of the developing sleeve, the end portions of the developing sleeve that are located at both sides of the central portion being no-magnet portions; and seal members supported by the housing, the seal members each including: a shielding portion that shields, from the developer, either one of portions of the photoreceptor that are located opposite the no-magnet portions; and a contact portion that is in surface contact with either one of end portions of the photoreceptor farther from a center of the photoreceptor than the no-magnet portions in the direction along the rotation axis, wherein each of the seal members includes, at an end thereof closer to the center of the photoreceptor than the other end in the direction along the rotation axis, a non-contact portion that is not in contact with the photoreceptor.