Patent ID: 8142314

Claim:
A tensioner for tensioning a flexible drive, comprising: a spindle having a base, said base configured for mounting on a surface of an engine; a tensioner arm mounted on said spindle for rotatable movement about a first axis, said tensioner arm having a pulley rotatably mounted about a second axis, said second axis being spaced from and parallel to said first axis; a coil spring acting between the spindle and the tensioning arm urging the tensioner arm to rotate about said first axis in a tensioning direction and bias the tensioner arm and the pulley into tensioning engagement with a flexible drive; a bushing mounted between the tensioner arm and spindle to allow the tensioner arm to pivot about the spindle and provide a first frictional force dampening movement of said tensioner arm about said spindle; a dampening shoe mounted between the coil spring and the tensioner arm, wherein said coil spring expands radially as the tensioner arm is urged in a direction opposite the tensioning direction, and coils of the spring press the dampening shoe into greater frictional engagement with the tensioner arm as the coil spring expands radially and relieve the frictional engagement with the tensioner arm as the coil spring contracts radially thereby providing a varying second frictional force dampening movement of said tensioner arm about said spindle.