Method of cleaning residual toner from drum and rollers of image forming apparatus

摘要

A method for cleaning an image-forming apparatus. Toner is charged to the first polarity prior to transferring the toner image to the print medium and accidentally inverted from the first polarity to a second polarity opposite to the first polarity during the transfer of the toner image to the print medium. When performing a cleaning operation, a first voltage of a first polarity is applied to at least one of a charging roller and a cleaning roller in contact with a surface of a photoconductor. The surface of the photoconductor is charged to a second voltage. The second voltage has a smaller value than the first voltage and is of the same polarity as the first voltage. Therefore, the toner of the second polarity sandwiched between the charged surface of the photoconductor and the at least one of the charging roller and cleaning roller is inverted in polarity, i.e., from the second polarity to the first polarity by triboelectric charging. If the first voltage is applied to the cleaning roller, the photoconductor may be charged to the second voltage by a transfer device or by a charging device. Alternatively, if the first voltage is applied to the charging roller, the photoconductor may be charged to the second voltage by a cleaning device or by the transfer device.