Patent ID: 7223202
Filing Date: 2007-05-29
Classification: F16F,F16H,Y10T

Abstract:
1. An electrically variable transmission with at least one electric motor and a rotatable torsional damper assembly, the torsional damper assembly comprising: a torsional spring operable to eliminate or reduce compression pulses and torsionals; a clutch assembly having a hydraulically operable piston for selectively locking out said torsional spring; at least one electric motor operable to cancel out the compression pulses when the torsional spring is locked out; and a hydraulic fluid applicable to opposing sides of said piston to sufficiently hydraulically balance said piston so as to prevent the clutch assembly from locking out said torsional spring at least partially in response to the rotational speed of said damper, thereby enabling said torsional spring to eliminate the torsionals.