Torsional vibration damper or decoupler with coiled wire springs in a drive pulley

Drive pulley 11 with a hub 12 and a wheel rim 14, which are rotatably mounted onto each other, with at least two oppositely wound wire springs 15, 16 which are installed around the rotation axis wound between the hub and the disc rim biased against each other and their respective one end opposite the hub 12 and whose respective other end is fixed with respect to the pulley rim 14 in the direction of rotation, wherein at least one of the wire springs 15, 16 opposite a curved support surface 45 on one of the parts - the hub and the disc rim 14 - starting an increasing over the circumference of the radial distance from a contact region 44, has, at the rotation of the parts - is progressively reduced to zero against one another under extension of the bearing region 44 and shortening of the free effective length of the spring - the hub 12 and the pulley rim fourteenth