NON-LINEAR, MULTI-SPEED, BI-DIRECTIONAL FACSIMILE SUBSCAN DRIVE CONTROL

摘要

The bi-directional facsimile subscan drive control can be operated at a number of desired subscan speeds and provides for the rapid return of the scan head (13). A single, bidirectional permanent magnet synchronous motor is operated as a stepping motor to provide the driving force needed at the various subscan speeds and for the return of the scan head to the start position. This is accomplished without the use of any clutches or the use of different gearing for different speeds. The control permits the use of a suitable return speed for the scan head while still providing for a sufficient number of steps for each scan for the production of an acceptable copy.