| 摘要 |
PURPOSE:To reduce friction between a bush and the sprocket wheel by a method wherein a chain support section is projected from the side face of the sprocket wheel to support the bushed chain at the outer perpheral side of the sprocket wheel by designing the pitch of the teeth of the sprocket wheel so as to be larger than the same of the bushed chain contacted to the sprocket wheel. CONSTITUTION:The support section 12A is projected from the side face of the sprocket wheel 11 at the vicinity of the root of the teeth 12 while inflated sections 14A, having substantially the same inflations as those around the bushes of the chain, are inflated at both ends of the bushed link plate 14 of the bushed chain 13 to abut the support section 12A against the inflated section 14A. According to this method, the location of the bushed chain 13 to be contacted to the sprocket wheel 11 is displaced to the outer peripheral side of the sprocket wheel 11 than the normal pitch circle of the wheel. The bush 1 of the bushed chain 13, displaced to the outer peripheral side of the sprocket wheel 11, is contacted obliquely to the root of the teeth 12 of the sprocket wheel 11 at only the foremost section thereof in the revolving direction. A contacting surface pressure between the bush 1 and the root of the teeth 12 is scattered to the support section 12A and the inflated section 14. |
