Abstract: The present invention includes a flywheel assembly having a first flywheel, a second flywheel, a viscous damper mechanism 3 disposed therebetween, and a boss member 5. The second flywheel is supported on the first flywheel so as to be relatively rotatable via the viscous damper mechanism. The viscous damper mechanism 3 includes disc-shaped plates 9, each having radially inner serrations 9d on radially inner surface thereof. The boss member 5 has radially outer serrations 5a. The boss 5 and plates 9 are provided with a thermal expansion differential prior to assembly. After assembly, the serrations 5a on the boss securely engage the serrations 9d on the inner surface of the plates 9. The plates 9 may be heated or the boss 5 may be cooled to provide a thermal expansion differential.

Abstract: A flywheel assembly having a first flywheel, a second flywheel, a viscous damper mechanism (3) disposed therebetween, and a boss member (5). The second flywheel is supported on the first flywheel so as to be relatively rotatable via the viscous damper mechanism. The viscous damper mechanism (3) includes disc-shaped plates (9), each having radially inner serrations (9d) on radially inner surface thereof. The boss member (5) has radially outer serrations (5a). The boss (5) and plates (9) are provided with a thermal expansion differential prior to assembly. After assembly, the serrations (5a) on the boss securely engage the serrations (9d) on the inner surface of the plates (9). The plates (9) may be heated or the boss (5) may be cooled to provide a thermal expansion differential.

Abstract: A flywheel assembly comprises a first flywheel connectable to an engine, a second flywheel, and an inter-flywheel viscous damping mechanism, providing viscous damping through a fluid of flywheel torsional vibrations. The second flywheel is rotatably supported on the first flywheel and has a friction facing on which a friction material presses. The second flywheel includes an annular capturing channel provided radially inward of the friction facing for capturing fluid from leakage driven on the friction facing side by centrifugal force, and a plurality of through-holes, extending from the capturing channel to a space between the flywheels, for guiding fluid captured by the capturing channel to the space.

Abstract: A flywheel assembly comprises a first flywheel connectable to an engine, a second flywheel, and an inter-flywheel viscous damping mechanism, providing viscous damping through a fluid of flywheel torsional vibrations. The second flywheel is rotatably supported on the first flywheel and has a friction facing on which a friction material presses. The second flywheel includes an annular capturing channel provided radially inward of the friction facing for capturing fluid from leakage driven on the friction facing side by centrifugal force, and a plurality of through-holes, extending from the capturing channel to a space between the flywheels, for guiding fluid captured by the capturing channel to the space.

Abstract: A flywheel assembly comprises a first flywheel connectable an engine, a second flywheel, and an inter-flywheel viscous damping mechanism, providing viscous damping through a fluid of flywheel torsional vibrations. The second flywheel, is rotatably supported on the first flywheel and has a friction facing on which a friction material presses. The second flywheel includes an annular capturing channel provided rapidly inward of the friction facing for capturing fluid from leakage driven on the friction facing side by centrifugal force, and a plurality of through-holes, extending from the capturing channel to a space between the flywheels, for guiding fluid captured by the capturing channel to the space.