Patent ID: 7869736
Filing Date: 2011-01-11
Classification: G03G

Abstract:
1. A transfer unit which is mounted to an apparatus main body of an image forming apparatus, the transfer unit comprising: a transfer belt which extends between a plurality of rollers so as to be capable of running in an endless manner, the transfer belt receiving on its front surface or a recording sheet placed on the front surface a toner image which is borne on an image bearing member in accordance with image information; a bending roller having a peripheral surface which is pressed against the front surface side of the transfer belt to bend inwardly the transfer belt which is in a state of extend between the plurality of rollers so as to be capable of running in an endless manner; a bending roller cleaning member which cleans the peripheral surface of the bending roller; a front surface side cleaning mechanism which cleans a front surface side of the transfer belt; and a collection section which collects a foreign object which is removed by both the bending roller cleaning member and the front surface side cleaning mechanism, wherein the front surface side cleaning mechanism includes: a cleaning brush which has a rotational shaft extending in the same direction as a rotational shaft of each of the rollers which rotate the transfer belt in an endless manner, the cleaning brush having bristles implanted thereto; a collection roller which collects from the cleaning brush a foreign object which is removed from the surface of the transfer belt by the cleaning brush; and a collection roller cleaning member which is a blade-like member whose leading end comes in contact with the peripheral surface of the collection roller to remove the foreign object from the collection roller; the collection roller and collection roller cleaning member are provided in a space formed by bending the transfer belt with the bending roller on an upstream side from the bending roller and the bending roller cleaning member in the running direction of the transfer belt, a position at which the collection roller cleaning member comes in contact with the collection roller is under a position at which a foreign object is removed from the bending roller by the bending roller cleaning member, and the collection section is arranged at a position under both the position at which the collection roller cleaning member comes in contact with the collection roller and the position at which the foreign object is removed from the bending roller by the bending roller cleaning member.