| 摘要 |
A tensioner for a power transmission belt that is adapted to be operated in an endless path is provided and comprises a support unit for being fixed relative to the belt, a belt engaging unit carried by the support unit and being movable relative thereto, a mechanical spring unit operatively associated with the support unit and the belt engaging unit for urging the belt engaging unit relative to the support unit and against the belt with a force to tension the belt, and a frictional dampening unit operatively associated with the support unit and the belt engaging unit to dampen the movement of the belt engaging unit relative to the support unit in at least one direction of movement thereof. The dampening unit has a longitudinal axis and the support unit comprises a shaft having a longitudinal axis and being fixed from movement relative to the belt engaging unit. The belt engaging unit has a portion thereof rotatably carried by the shaft so as to rotate relative to the shaft. The dampening unit comprise a pair of frictionally engaging first and second parts with the first part comprising an annular pad of friction material that is coaxially disposed and axially movable on the shaft relative to the second part and another spring that urges the first part against the second part with a certain spring force. |
