Abstract: A torsional vibration damper which comprises of a hub 12 having a central hole 3 to be inserted on the crankshaft and being formed to have a recess opened on one side, a disc 4 extending from the hub 2, a rim 5 being bent and extending from the periphery of the disc 4, a rubber layer 6 attached on the outer surface of the rim 5, and a ring member 8 or pulley inserted on the outer surface of the rubber layer 6, wherein a polygonal recess 10 is formed on the connecting area between the hub 2 and the disc 4 so that the polygonal recess 10 surrounds the hub 2.

Abstract: A torsional vibration damper which comprises of a hub 12 having a central hole 3 to be inserted on the crankshaft and being formed to have a recess opened on one side, a disc 4 extending from the hub 2, a rim 5 being bent and extending from the periphery of the disc 4, a rubber layer 6 attached on the outer surface of the rim 5, and a ring member 8 or pulley inserted on the outer surface of the rubber layer 6, wherein a polygonal recess 10 is formed on the connecting area between the hub 2 and the disc 4 so that the polygonal recess 10 surrounds the hub 2.

Abstract: The invention is a damper pulley which comprises of a cylindrical hub 12 being made of cast iron and coupled to the crankshaft of the engine, a hub plate 16 being made of steel plate and having a central hole 22 on which the hub 12 is attached and a rim 24 at the periphery of it, a rubber layer 18 being attached on the rim 24 of the hub plate 16, and a pulley attached on the outer surface of the rubber layer 18.