| 摘要 |
<p>A pulley apparatus and auto-tensioner which have a simple constitution and, despite this, can impart torsion-spring properties to an inner member and an outer member. Due to the torsion-spring properties, the fluctuations in tension, rotational speed, etc. of a belt stretched on a pulley part disposed on either of the inner member and the outer member can be effectively mitigated. The apparatus comprises an outer member having an outer track surface on the inner peripheral side thereof, an inner member which has, on the outer peripheral side, an inner track surface facing the outer track surface and which is disposed so as to be rotatable relative to the outer member, and rolling elements rollably interposed between the outer track surface and the inner track surface. At least one of the inner track surface and the outer track surface has, in at least part thereof, a different-shape track surface which serves to gradually narrow the space where the rolling elements are sandwiched and which imparts a rotational force in such a direction that a phase difference generated between the outer member and the inner member as a result of the relative rotation of the outer member and the inner member is eliminated, while allowing the rolling elements to roll with the relative rotation.</p> |
