Electrical drive for scanning optics in a continuously variable reduction copier

摘要

A scanning continuously variable reduction electrophotographic copier includes a servo motor for driving the document scanning carriages. Servo motor, and therefore carriage motion parameters of velocity, duration of acceleration and deceleration, length or time duration of travel and time of start of scan are selectable to produce a selected reduction ratio within a continuous range of reduction ratios. In one embodiment, three partially overlapping hybrid servo loops are used, one for acceleration and deceleration, another for constant velocity motion and a third for precise stopping control. In another embodiment, a single loop controls the entire motion.