Torsional damper device for a clutch disk

Abstract

A torsional damper device comprises coaxial parts adapted to rotate relative to one another within predetermined limits. Two of the coaxial parts mesh together with clearance, the meshing portions defining predetermined limits of relative angular movement. A circumferentially acting elastic element is disposed between these two coaxial parts to resist such relative angular movement. A centering device cooperating with the meshing portions is adapted to urge the two coaxial parts circumferentially towards a rest position between the predetermined limits of relative angular movement. These two coaxial parts are formed with shoulders and the centering device comprise at least one elastic member, constituting part of the circumferentially acting elastic element, colocated with the meshing portions. A respective bearing member is disposed between each end of the elastic member and the associated shoulder. Thus the elastic member bears on the shoulders through the intermediary of the bearing members. Each bearing member is formed with a concave dihedron and when the two coaxial members are in a rest position the shoulders define a complementary dihedron. At least one of the bearing members is in one piece with the elastic member, whose corresponding circumferential end is shaped to form the corresponding dihedron.