Patent ID: 7367908

Claim:
A belt tensioning device for a belt drive having at least two belt pulleys and a continuous belt, the belt tensioning device comprising: a torsion spring assembly with a longitudinal axis (A 2 ); a tensioning arm which, at one end, is arranged at the torsion spring assembly so as to be aligned approximately radially relative to the longitudinal axis (A 2 ); and a tensioning roller rotatably arranged at the other end of the tensioning arm, wherein an axis of rotation (A 1 ) of the tensioning roller extends substantially parallel relative to the longitudinal axis (A 2 ) of the torsion spring assembly and wherein the tensioning arm can be resiliently supported relative to the rack so as to oscillate around the longitudinal axis (A 2 ); wherein the torsion spring assembly comprises a plurality of individual torsion bars which, by being clamped together at their ends, form a bundle and are in line contact or surface contact with one another.