Patent ID: 9057988
Filing Date: 2015-06-16
Classification: G03G

Abstract:
1. A developing device for developing an electrostatic latent image on an image carrier by using two-component developer containing toner and magnetic carrier, comprising: a magnetic member having a plurality of magnetic poles along a circumferential direction of the magnetic member; a developing sleeve in which the magnetic member is inserted, transporting developer to a developing area facing the image carrier; and a restriction member made of magnetic material, disposed along a rotational axis of the developing sleeve so as to face an outer circumferential surface of the developing sleeve, and restricting the amount of developer to be transported to the developing area to be no greater than 250 g/m the magnetic member generates magnetic flux such that an average of absolute values of magnetic flux density within a restriction area falls within a range of 40 mT to 70 mT under a condition that no developer exists within the restriction area, the restriction area extending along the outer circumferential surface between a closest point on the outer circumferential surface, which is closest to the restriction member, and a point 2 mm upstream from the closest point in a rotational direction of the developing sleeve, and having a height that is half a minimum distance between the closest point and the restriction member.