High-low shifting active torque management continuously variable transmission system

A vehicle including an active torque management continuously variable transmission system, the vehicle comprising:

• an engine to generate torque;
• a continuously variable transmission (CVT) including,
• a primary pulley in operational communication with the engine to receive the torque generated by the engine,
• a secondary pulley, and
• an endless looped member engaged with the primary pulley and the secondary pulley to pass the torque between the primary pulley and the secondary pulley;
• a high variable torque limiting clutch selectively coupling the torque between the secondary pulley of the CVT and at least one drive axle of the vehicle when the vehicle is traveling in a high range, the high variable torque limiting clutch configured to dynamically adjust a slippage threshold of the high variable torque limiting clutch to be above a then current output torque of the CVT and below a then current clamping force generated by the primary pulley and the secondary pulley on the endless looped member when the high variable torque limiting clutch is activated;
• and
• a low variable torque limiting clutch selectively coupling the torque between the secondary pulley of the CVT and the at least one drive axle of the vehicle when the vehicle is traveling in a low range, the low variable torque limiting clutch configured to dynamically adjust a slippage threshold of the low variable torque limiting clutch to be above the then current output torque of the CVT and below the then current clamping force generated by the primary pulley and the secondary pulley on the endless looped member when the low variable torque limiting clutch is activated.

A method of operating a high-low active torque management continuously variable transmission system, the method comprising:

• determining a then current output torque of a continuously variable transmission (CVT);
• determining a then current clamp force of the CVT on an endless looped member;
• determining a slippage threshold that is less than the then current clamp force and higher than the then current output torque of the CVT;
• and
• setting a slip torque of a high variable torque limiting clutch and a low variable torque limiting clutch that are positioned between the CVT and at least one drive axle of a vehicle based on the slippage threshold.