| 摘要 |
A positioning device for preventing an endless belt passed over a plurality support rollers from being shifted to either of opposite sides in the axial direction of the rollers. A pair of forcing elements are located at both ends of at least one of the support rollers for forcing back, when the belt is shifted toward either of opposite ends of the support roller to contact the end of the latter, the belt toward the center of the roller in the axial direction of the roller. The forcing elements each are implemented as a plurality of spaced flanges. The maximum diameter of the flanges sequentially increases from the innermost flange to the outermost flange in the axial direction of the roller. The plurality of flanges may be replaced with a single spiral flange. |
