Blade-type torsional damper

A torsional damper for a torque transmission device, comprising:

• a first element (1) and a second element (2) rotationally movable with respect to one another around a rotation axis X;
• and
• a first damping means and a second damping means for transmitting a torque and for damping rotational irregularities between the first element and the second element, each damping means comprising:
• an elastically deformable blade (9) integral with one of said first and second elements and having a portion (12) for fastening the blade to said first or second element and an elastic portion (13), the elastic portion proceeding circumferentially from the fastening portion to a free distal end (29),
• an abutment element (10) carried by the other of said first and second elements and configured to interact with the elastic portion of the blade of said damping means, the elastic portion of the blade being configured such that for an angular deflection between the first and second elements with respect to an inactive angular position, the abutment element applies a flexural load onto the blade, producing jointly a reaction force capable of returning the first and second elements to said inactive angular position,
• the elastic portion of the blade of the first damping means proceeds circumferentially beyond the fastening portion of the blade of the second damping means, in such a way that at least part of the elastic portion of the blade of the second damping means is arranged radially between the free distal end of the blade of the first damping means and the rotation axis X.