Patent ID: 7764889

Claim:
An image-forming device comprising: a housing; a cleaning target member provided in the housing; a cleaning unit that applies a predetermined voltage to the cleaning target member to remove toner from the cleaning target member through an electrostatic force, the predetermined voltage having a predetermined absolute value; a toner detection unit that detects an amount of toner on the cleaning target member at least twice, the detected amount of toner including a first amount of toner and a second amount of toner, the first amount of toner being detected when a first voltage having a first absolute value is applied as the predetermined voltage at a first time, the second amount of toner being detected when a second voltage having a second absolute value is applied as the predetermined voltage at a second time, and the second time being later than the first time; and a control unit that determines the predetermined absolute value on the basis of the first amount of toner and the second amount of toner.