Patent ID: 7823720

Claim:
A belt transport device comprising: a drive roller which is driven by a power source; a driven roller which is held in a rotatable manner; an endless belt which is wound on the drive roller and the driven roller; a band-like detecting section which is arranged on the endless belt in a circumferential direction of the endless belt; a sensor which detects the band-like detecting section; a displacement unit which displaces a relative positional relationship between the band-like detecting section and the sensor in a width direction of the endless belt; and a controller which controls the displacement unit to displace the relative positional relationship so as to satisfy the expression Tx≠n×Ty in the range in which the band-like detecting section and the sensor are opposed to each other, where Tx is an oblique traveling cycle of the endless belt, Ty is a revolution cycle of the endless belt and n is a fraction not more than ½ or an integer of 1 or 2.