Method of controlling clamping of wedge-actuated CVT and powertrain with wedge-actuated CVT

A powertrain comprising:

• a continuously variable transmission (CVT) that includes:
• an input wedge component mounted on an input shaft;
• wherein the input wedge component is configured to provide an input wedge force on an input movable sheave of an input pulley when a direction of drive torque on the input shaft is in a forward drive direction;
• an output wedge component mounted on an output shaft;
• wherein the output wedge component is configured to provide an output wedge force on an output movable sheave of an output pulley when a direction of load torque on the output shaft is opposite to the forward drive direction, the output pulley connected with the input pulley via an endless rotatable device;
• an input actuator operable to provide an axial force on the input movable sheave;
• and
• an output actuator operable to provide an axial force on the output movable sheave;
• and
• an electronic controller operatively connected to the CVT and configured to:
• monitor powertrain operating conditions;
• calculate a commanded clamping force based on the powertrain operating conditions;
• wherein the commanded clamping force includes a commanded clamping force of the input pulley on the endless rotatable device, and a commanded clamping force of the output pulley on the endless rotatable device;
• calculate an axial component of the input wedge force of the input wedge component based on estimated drive torque on the input shaft, an angle of a wedge surface of the input wedge component that interfaces with the input movable sheave, an angle of a pulley surface of the input movable sheave, and an outer radius of the input wedge component;
• and
• activate at least one of the input actuator and the output actuator such that the axial component of the input wedge force and the axial force of the input actuator together provide the commanded clamping force of the input pulley, and an axial component of the output wedge force and the axial force of the output actuator together provide the commanded clamping force of the output pulley.

A powertrain comprising:

• a continuously variable transmission (CVT) that includes:
• an input wedge component mounted on an input shaft;
• wherein the input wedge component is configured to provide an input wedge force on an input movable sheave of an input pulley when a direction of torque on the input shaft is in a forward drive direction;
• an output wedge component mounted on an output shaft;
• wherein the output wedge component is configured to provide an output wedge force on an output movable sheave of an output pulley when a direction of load torque on the output shaft is opposite to the forward drive direction, the output pulley connected with the input pulley via an endless rotatable device;
• an input actuator operable to provide an axial force on the input movable sheave;
• an output actuator operable to provide an axial force on the output movable sheave;
• a force sensor mounted on a wedge surface of the input wedge component that interfaces with the input movable sheave of the input pulley;
• and
• an electronic controller operatively connected to the CVT and configured to:
• monitor powertrain operating conditions;
• calculate a commanded clamping force based on the powertrain operating conditions;
• wherein the commanded clamping force includes a commanded clamping force of the input pulley on the endless rotatable device, and a commanded clamping force of the output pulley on the endless rotatable device;
• determine the input wedge force via the force sensor;
• and
• activate at least one of the input actuator and the output actuator such that an axial component of the input wedge force and the axial force of the input actuator together provide the commanded clamping force of the input pulley, and an axial component of the output wedge force and the axial force of the output actuator together provide the commanded clamping force of the output pulley.