Patent ID: 6763743
Filing Date: 2004-07-20
Classification: F16F,Y10T

Abstract:
A flywheel device for a prime mover, which is arranged between an output shaft and a driven shaft of the prime mover,the flywheel device comprising: a plate having a fitting portion in a radially outer portion thereof and mounted to the output shaft in a manner concentric therewith; and an inertial mass member having an annular shape, said inertial mass member having a fitting portion which is fitted to the fitting portion of said plate, whereby said inertial mass member is concentrically attached to said plate, for transmitting torque from the prime mover to the driven shaft while reducing variation in the torque; further comprising a linkage connecting between a portion of said inertial mass member radially inward of the fitting portion thereof and the driven shaft; and a damping mechanism arranged in said linkage, for transmitting the torque from the prime mover to the driven shaft while damping torsional vibration thereof; wherein said damping mechanism comprises at least one coil spring, and wherein said linkage includes a pair of spring holder plates for holding said at least one coil spring in a spring chamber formed therebetween; and wherein said damping mechanism further comprises a pair of friction discs, grease contained in the spring chamber and having a predetermined coefficient of viscosity, said at least one coil spring having a predetermined spring modulus, and wherein the coefficient of viscosity of the grease and the spring modulus of each coil spring are selected such that a rotational vibration system including the prime mover and the driven shaft has a resonance frequency which is outside a range of values thereof corresponding to a predetermined rotational speed region of the prime mover.