Patent ID: 9335665
Filing Date: 2016-05-10
CPC Classification: G03G

Claim Text:
1. An image forming apparatus including an alternating transformer that splits a given alternating voltage into a first alternating voltage and a second alternating voltage, comprising: a developer bias application unit that, during image formation, applies to a sleeve roller a pulsed sleeve roller voltage composed of a first alternating voltage superimposed on a first direct voltage, and also applies to a magnetic roller a second alternating voltage and a second direct voltage separately in order to apply to the magnetic roller a pulsed magnetic roller voltage composed of the second alternating voltage superimposed on the second direct voltage; an alternating voltage shutoff unit that stops applying the second alternating voltage to the magnetic roller before measurement of discharge starting voltage; and a discharge starting voltage measurement unit that when the application of the second alternating voltage to the magnetic roller is stopped, increases the given alternating voltage of the alternating transformer to measure the discharge starting voltage that occurs between the sleeve roller and the magnetic roller.