摘要 |
A mechanical tensioner that includes a pulley arm with a tension pulley for a tension element drive of an internal combustion engine. The pulley arm is mounted to a mounting base that is fixedly attached to the engine. A spring that functions in compression and torsion is located about a pivot axis on the mounting base, with one end connected to the pulley arm and the other end attached to the mounting base. The spring provides torsion to the pulley arm to maintain tension on the tension element, and is also compressed between a mounting flange of the pulley arm and a support flange on the mounting base to transmit an axial force between the pulley arm and an outer hub that is fixed to the mounting base. A shaped bush which functions at least as a damping element, and can also function as a bearing, is located in the space between the outer hub and the pulley arm. The outer surface of the outer hub, the bush and the inner portion of the pulley arm are in the shape of a tractrix pseudosphere to provide increased life and reduced wear. |