Abstract: In an electrophotographic print mechanism wherein one motor drives two or more removable toner cartridges, the presence of each cartridge is sensed and reported to the motor controller. If one or more cartridges are removed, such as for single-color printing, the motor control equation parameters are altered to compensate for the altered static torque load experienced by the motor. The parameters may be the proportional, integral, and/or derivative gains for one or more PID controllers.

Abstract: An image-forming apparatus includes a toner-supplying roller and a developing roller assembled into a developing unit. The toner-supplying roller supplies toner to the developing roller. The developing roller applies the toner to an electrostatic latent image on a photoconductor to form a toner image. The toner image is transferred onto a print medium at a transfer unit, and finally fused into a permanent image at a fixing unit. The toner includes a wax that remains solid at room temperature and melts at a fixing temperature. At least one of the toner-supplying roller and the developing roller is a silicone roller on which oligomer in the form of siloxane is deposited. The silicone roller contains non-cured siloxane in the range of 10 to 8000 PPM.