Patent ID: 7426984
Filing Date: 2008-09-23
Classification: F16F

Abstract:
1. A torsional vibration damper, comprising: a primary mass adapted to be coupled to an engine crankshaft for rotation about a rotational axis of the engine crankshaft, the primary mass defining a substantially ring-shaped Chamber that is divided into at least two portions; a secondary mass relatively rotatably connected to the primary mass and connectable with a clutch; and a damping unit for coupling the primary and secondary masses to each other in a rotatable elastic manner, wherein the damping unit comprises: a plurality of coil springs situated in series and disposed one after the other within the divided portions of the ring-shaped chamber, a pair of end guides slidably disposed within each divided portion of the ring-shaped chamber and supporting outer ends of the coil Springs among the plurality of coil springs; and at least a pair of first and second wedge-shaped friction guides slidably disposed between neighboring coil springs and configured to be rubbed against at least one of an inner wall and an outer wall of the ring-shaped chamber in response-to compressions of the coil springs such that a friction force is generated in response to a relative rotation between the primary and secondary masses, the first and second wedge-shaped friction guides facing each other along facing surfaces thereof, wherein each of the facing surfaces of the first and second wedge-shaped friction guides are entirely slanted with respect to a radial direction of the primary mass; and wherein an overall radial thickness of the second wedge-shaped friction guide is less than that of the first wedge-shaped friction guide.