| 摘要 |
A belt tensioning unit (1′), in particular for a belt pulley plane of an internal combustion engine, including a base part (2) arranged in a rotationally fixed manner and a tensioning part, which is mounted on the base part (2) and can perform relative rotations to a limited extent about a rotation angle (α) with respect to the base part against the action of at least one torsion spring (6). During a relative rotation between the base part (2) and tensioning part, the at least one torsion spring (6) forms a frictional engagement by changing a diameter thereof via a friction device (8a) formed by at least one friction segment (9) acted on by the at least one torsion spring (6) and a friction surface (10a) provided on the tensioning part. In order to design the frictional torque of the friction device (8a) for the entire operating range of the belt tensioning unit (1′), in addition to the nominal position, according to the invention the friction properties of the friction surface (10a) are set to vary depending on the rotation angle (α). |
