Patent ID: 7937009

Claim:
A controlling method of an image forming apparatus, comprising: developing an electrostatic latent image of a photoconductive medium using a toner supplied from a developing apparatus fixed around a photoconductive medium, the toner being supplied from a supplying roller to a developing roller of the developing apparatus by a bias voltage difference; and collecting remainder toner which is not in use during the developing operation and remains on the developing roller to the supplying roller, wherein the collecting comprises supplying the supplying roller with a bias voltage having a lower absolute value than a bias voltage of the developing roller, wherein the collecting further comprises supplying the developing roller with a bias voltage which has an absolute value greater than an absolute voltage value of an electrostatic latent image area of the photoconductive medium and less than a non-electrostatic latent image area of the photoconductive medium, and wherein the developing operation comprises: a first supplying operation of supplying the developing roller with a bias voltage having a lower absolute value than a voltage of the supplying roller; and a second supplying operation of supplying the developing roller and the supplying roller with bias voltages having the same absolute value.