Patent ID: 9645531
Date: 2017-05-09
CPC Classifications: G03G

Claim:
1. An image forming apparatus comprising: a plurality of photosensitive drums that carry toner images of each color respectively; a plurality of transfer rollers respectively provided to face each of the photosensitive drums and transferring the toner images carried on surfaces of the photosensitive drums to a member to be transferred; one power supply that applies a voltage to each of the transfer rollers; a prediction unit that predicts whether a surface potential of at least one of the plurality of photosensitive drums becomes less than a predetermined potential during continuous print in which printing is continuously performed on a plurality of sheets; and a control unit that, when the prediction unit predicts that the surface potential of at least one of the plurality of photosensitive drums becomes less than the predetermined potential, whenever transfer of toner images corresponding to a predetermined number of sheets is completed by the plurality of transfer rollers in execution of the continuous print, interrupts the continuous print for a predetermined time, applies a voltage with a polarity equal to a polarity of toner to the plurality of transfer rollers by the power supply or stops application of the voltage to the plurality of transfer rollers during the predetermined time, and restarts the continuous print after the predetermined time passes.