Cleaning system for charging drum of an image forming apparatus

摘要

In an image forming apparatus having a charging member for charging a photoconductive element in the form of a drum or a belt in contact therewith, a cleaning member cleans the surface of a charge roller contacting the photoconductive element. The cleaning member is usually spaced apart from the surface of the charge roller, but the former is caused to contact the latter only for a predetermined period of time at predetermined intervals. This frees the charge roller from excessive cleaning due to the cleaning member and, therefore, obviates defective images. The time for causing the cleaning member to contact the charge roller may be changed on the basis of the degree of contamination of the charge roller in order to cope with accidental smears brought about on the charge roller.