Variable inertia flywheel

A flywheel and clutch assembly for transferring torque from an engine crankshaft to a transmission input shaft, the assembly comprising:

• a primary mass adapted to be rotationally fixed to the engine crankshaft;
• a clutch disc adapted to be rotationally fixed to the transmission input shaft;
• a secondary mass rotationally engageable with the clutch disc for transferring torque thereto;
• a spring assembly coupled between the primary mass and the secondary mass;
• and
• a latcher connected between the primary mass and the secondary mass that is engageable to rotationally fix the primary mass to the secondary mass, the latcher including a pair of cavities and a channel extending between the cavities defined by a first member, which forms a portion of the primary mass, and a second member, which forms a portion of the secondary mass, with the latcher further including a viscous fluid contained within the cavities and channel that has a selectively variable viscosity, and with the latcher including a viscosity means for selectively causing the viscosity of the fluid to change.

A vehicle driveline comprising:

• an engine crankshaft;
• a transmission input shaft;
• and
• a flywheel and clutch assembly including a primary mass rotationally fixed to the engine crankshaft, a clutch disc rotationally fixed to the transmission input shaft, a secondary mass rotationally engageable with the clutch disc for transferring torque thereto, a spring assembly coupled between the primary mass and the secondary mass, and a latcher connected between the primary mass and the secondary mass that is engageable to rotationally fix the primary mass to the secondary mass.