1. Field of the Invention
This application relates to a developing device and an image forming apparatus including the developing device.
2. Description of the Related Art
An image forming apparatus employing electrophotographic technology, such as a printer, a copier, a facsimile machine or a multifunction peripheral (MFP), performs processes of charging, exposing, developing, transferring, cleaning and neutralizing on a photosensitive drum or in the vicinity thereof. A toner image formed on the photosensitive drum is transferred to and fixed on a sheet as a medium.
A printer that incorporates a belt-type developing device, which includes a developing belt and a developing roller, is well known. The developing belt provides an electrostatic latent image formed on a photosensitive drum with toner to form a toner image thereon. The developing roller supplies the developing belt with the toner and scrapes residual toner, which does not contribute to forming the toner image, off the developing belt. A voltage for supplying the developing belt with the toner is applied to the developing roller. Japanese Patent Laid-Open No. 07-134646 discloses one such developing device.
In the aforementioned belt-type developing device, however, the residual toner cannot be fully removed from the developing belt, thereby forming a residual image caused by the residual toner on a sheet. This will cause adverse effects on print quality.