Movement roller, and belt driving device and image forming device using same

Abstract

A protrusion (13a) and a protrusion (13b) are formed a predetermined distance apart in the direction of a shaft in the outer circumferential surface of the roller main body (11). The cross sections of the protrusion (13a) and the protrusion (13b) are shaped such that a center portion of the roller main body (11) in the direction of the shaft is a boundary (14), and that on the left side of the boundary (14), a vertex (131a) is displaced to the left side from the perpendicular bisector (133a) of an opposite side (132a) whereas on the right side of the boundary (14), a vertex (131b) is displaced to the right side from the perpendicular bisector (133b) of an opposite side (132b). In this way, in a metallic movement roller that moves a strung endless belt, the winding movement and the like of the belt can be prevented, and the belt can be intentionally moved in a specific direction.

Dependencies are inferred from the claim text.