Patent ID: 7877047
Filing Date: 2011-01-25
Classification: G03G

Abstract:
1. A developing device, comprising: a latent image carrier to carry a latent image; a developer carrier having therein a plurality of magnetic poles to generate a magnetic field, and carrying and conveying a two-component developer including a toner and a magnetic carrier; a developer regulating member to regulate a layer thickness of the two-component developer carried and conveyed by the developer carrier; a stirring section to stir the toner and the two-component developer removed from the developer carrier; and developer accumulation means for accumulating the two-component developer between the stirring section and the developer regulating member, wherein a portion of the two-component developer is fed back to the stirring section by the developer accumulation means, at least two pairs of the magnetic poles of a same polarity are disposed in a developing sleeve such that a first pair of the magnetic poles of the same polarity is disposed adjacent to a second pair of the magnetic poles of the same polarity, the developer accumulation means includes the plurality of magnetic poles disposed in a magnetic field generating means, both the first pair of the magnetic poles of the same polarity and the second pair of the magnetic poles of the same polarity are arranged on the developer carrier in a range downstream of a magnetic pole facing the latent image carrier and upstream of the developer regulating member in a direction of rotation of the developer carrier, and an additional magnetic pole is disposed in the developing sleeve downstream of the first and second pairs of the magnetic poles having the same polarity, the developer regulating member being disposed on the additional magnetic pole.