Patent ID: 8526872

Claim:
An image forming unit comprising: an image carrier on which an electrostatic latent image is formed; a developer that develops the electrostatic latent image formed on the image carrier; a toner supplier that supplies the developer with toner to form a toner image on the image carrier; and a cleaner that, after the toner image formed on the image carrier is transferred onto a transfer member, collects toner remaining on a surface of the image carrier, the toner supplier comprising: a cylindrical conveying passage member; and a toner conveying rotational body that (i) includes a rotational shaft, and a first spiral blade and a second spiral blade that are wound in directions opposite to each other on different areas along the rotational shaft, (ii) is inserted in the cylindrical conveying passage member, and (iii) is rotated so that the first spiral blade and the second spiral blade convey toner in convergent directions, wherein the rotational shaft is inclined at a predetermined angle with respect to a horizontal plane such that the second spiral blade is higher than the first spiral blade, and the cylindrical conveying passage member comprises: a fresh toner receiving opening configured to receive fresh toner and disposed at a first position along the inclined cylindrical conveying passage member where the first spiral blade is wound; a collected toner receiving opening configured to receive toner collected by the cleaner and disposed at a second position along the inclined cylindrical conveying passage member where the second spiral blade is wound, wherein the first position is lower than the second position; and a toner supplier opening that is disposed at a position where the fresh toner conveyed by the first spiral blade and the collected toner conveyed by the second spiral blade meet, so as to supply the conveyed fresh toner and the conveyed collected toner to the developer.