Torsion damper including a pre-damper having a housing with hooked tongues, in particular for a motor vehicle

A torsion damper comprising:

• a hub;
• a main damper plate surrounding the hub, the hub and main damper plate defining loose coupling means coupling the main damper plate and the hub together for limited relative rotation;
• a plurality of main guide rings disposed on either side of the main damper plate;
• means coupling the main guide rings together for simultaneous rotation;
• first circumferentially acting resilient means coupling the main damper plate and the main guide rings together;
• a pre-damper;
• and means mounting the pre-damper on one side of the main damper plate,
• wherein the pre-damper comprises:
• a housing having an axially oriented flange defining a plurality of hooked, resiliently deformable tongues which together define a first shoulder carried by the housing, the housing further defining a second shoulder carried thereby, the damper further comprising means mounting the housing with the said first shoulder being closer to the main damper plate than is the second shoulder, and the main damper plate having a plurality of apertures;
• coupling means comprising a plurality of coupling fingers carried by the housing, with each said coupling finger engaging in a complementary said aperture of the main damper plate, whereby to couple the housing to the main damper plate for rotation with the latter;
• a secondary damper plate within the housing and surrounding the hub;
• means coupling the secondary damper plate to the hub for rotation with the latter;
• two secondary guide rings;
• means mounting the said secondary guide rings in the housing for rotation with the housing but for axial movement with respect to the housing, with one said guide ring being arranged on a respective side of the main damper plate, and with the said first and second shoulders retaining the secondary guide rings between them;
• and second circumferentially acting resilient means, of lesser stiffness than the said first circumferentially acting resilient means, coupling the secondary guide rings to the said secondary damper plate,
• wherein each said hooked tongue is radially inward of a corresponding said coupling finger, for penetration into the said complementary aperture of the main damper plate associated with the same coupling finger.