Patent ID: 9158225
Filing Date: 2015-10-13
Classification: G03G

Abstract:
1. An image forming apparatus, comprising: an image bearing member which bears an electrostatic latent image; a developing device including: a voltage applying device which applies an alternate-current voltage to the developer carrying member; and a detecting device which detects information on a capacitance between the developer carrying member and the electrode member when the voltage applying device applies the alternate-current voltage to the developer carrying member during developing the electrostatic latent image, wherein the voltage applying device has, as the alternate-current voltage, a first alternate-current voltage having a first peak-to-peak voltage and a first frequency, and a second alternate-current voltage having a second peak-to-peak voltage higher than the first peak-to-peak voltage and a second frequency lower than the first frequency, and wherein the voltage applying device changes the first peak-to-peak voltage into the second peak-to-peak voltage if a number of sheets used to form an image is equal to or greater than a predetermined number.