Patent ID: 9557705
Date: 2017-01-31
CPC Classifications: G03G

Claim:
1. An image forming apparatus comprising: an image carrier on which a toner image is formed; a transfer unit configured to transfer the toner image to a sheet from the image carrier; a cleaner configured to remove toner remaining on the image carrier after the transfer; a waste toner container having a screw and being configured to contain the toner removed by the cleaner as waste toner; a sensor configured to sense an amount of the waste toner; a first determination unit configured to determine an amount of the waste toner in the waste toner container based on a number of sheets to which the toner image is transferred; a motor configured to drive the screw; a detection unit configured to detect a driving force of the motor; and a second determination unit configured to determine a state of the waste toner container based on the amount of the waste toner determined by the first determination unit or the driving force detected by the detection unit after the amount of the waste toner detected by the sensor is larger than a predetermined amount.