| 摘要 |
PROBLEM TO BE SOLVED: To sufficiently improve the bending rigidity of an idler pulley supporting structure while reducing the outer diameter size of a pulley mounting boss supporting an idler pulley. SOLUTION: A female screw formation region D and a counter bore region E are formed on the inner face of a mounting hole 22 of the pulley mounting boss 21 supporting the idler pulley 61 of a belt driving system. A boundary point between these regions is set at a position closer to the corner side in the direction of the depth of the mounting hole 22 than at a stress concentration position F on the outer peripheral face of the pulley mounting boss 21. Thus, a compressive force in the direction of the axial center is previously imparted to the stress concentration position F and its peripheral area and the bending rigidity around the stress concentration position is set to be higher. COPYRIGHT: (C)2008,JPO&INPIT |
