Patent ID: 7881636
Filing Date: 2011-02-01
Classification: G03G

Abstract:
1. A device for driving a belt, the device comprising: an endless belt member; a plurality of supporting rollers over which the endless belt member is supported, the supporting rollers include at least a driving roller that drives the endless belt member and a driven roller that is driven by a rotation of the endless belt member; a driving unit that drives the driving roller; a plurality of marks provided on the driven roller, the marks representing predetermined information using a pattern of varying lengths and pitches; a detecting unit that detects the marks on the driven roller at a predetermined position; and a control unit that controls a speed at which the driving unit drives the endless belt member based on a result of detecting the marks by the detecting unit, wherein the driven roller functions as a tension roller that applies a tension to the endless belt member, and the detecting unit is held by the tension roller.