Torsional damper for a vehicle transmission system

A torsional damper (2) of a friction disk (1) for a clutch for a vehicle transmission system, the torsional damper (2) comprising:

• an input element (6) rotationally movable around an axis (X) and exhibiting at least one window (15) comprising two angularly spaced lateral edges (20) and a radially external edge (21);
• an output element (8) rotationally movable around the axis (X) and exhibiting at least one window comprising two angularly spaced lateral edges and a radially external edge,
• an elastic return member (9) received simultaneously in the at least one window (15) of the input element (6) and in the at least one window of the output element (8) so as to generate a force acting against rotation of the output element (8) with respect to the input element (6);
• and
• a support disk (10) rotationally movable around the axis (X) and non-moveably attached to one of the input element (6) and the output element (10), the support disk (10) exhibiting at least one window (17) comprising at least one edge (25), the at least one edge (25) comprising at least one region (30) projecting radially into the at least one window of one of the input element (6) and output element (8) to which the support disk (10) is non-moveably attached,
• the input element (6) being a web, the output element (8) being two guide washers axially surrounding the web, and
• the support disk extending radially outwardly from the one of the input element (6) and the output element (10), the support disk (10) supporting at least one friction lining.