Patent ID: 8634737

Claim:
An image forming apparatus comprising: an image bearing member; toner image forming means for forming a toner image on said image bearing member; transfer means for transferring the toner image from said image bearing member onto a transfer material; a cleaning blade for removing a toner remaining on said image bearing member after the toner image is transferred while in contact with said image bearing member; a rotatable member, provided upstream of said cleaning blade, for carrying the toner and rotationally sliding on said image bearing member; a separating mechanism for removing the toner from said rotatable member, the separating mechanism is disposed in contact with said rotatable member, wherein said separating mechanism includes a toner sump for accumulating the toner in an area adjacent to said rotatable member so that the toner removed from said rotatable member is suppliable to said rotatable member; and control means for controlling at least one of said toner image forming means and said rotatable member so that an amount of the toner in the toner sump is estimated and kept in a predetermined range, wherein said control means detects a driving load of said rotatable member during non-image formation and estimates the amount of the toner in the toner sump.