An image forming apparatus includes a waste toner system that collects
waste toner in a waste toner container. An amount of waste toner
collected in the container is increased by using a driven toner
distributing member that distributes accumulated toner within the
container. The toner distributing member may be driven by a shared
speed-controlled motor that further drives an image forming process
member. The waste toner system may detect the accumulation of waste toner
by monitoring a drive control circuit while the toner distributing member
is being driven. For example, a logic circuit may detect the accumulation
of waste toner based on monitoring a predetermined frequency of interest
of a frequency domain transform of a motor control signal, the frequency
of interest associated with the shared motor driving the toner
distributing member.