Patent ID: 8403810

Claim:
A method including a system for controlling the torque transferable by a mechanical drive between an engine and a shaft of a vehicle, said mechanical drive having a clutch and a variable-speed drive for transmitting motion between an input shaft and an output shaft, the method comprising: providing a first actuator that acts on at least one member of said variable-speed drive; providing a second actuator that acts on at least a clutch, said second actuator determining a degree of engagement/release of said clutch; providing a measuring device configured for measuring torque to or from said variable-speed drive; providing an electronic central controller, said controller controlling said first and second actuators and said measuring device to protect said variable-speed drive and said clutch from mechanical overloading of the mechanical drive; recording torque transmission on a variable-speed drive, including recording an initial value of a velocity ratio between pulleys of the variable-speed drive, and an initial value of a speed of an input shaft of the variable-speed drive; from the initial value of the velocity ratio and the initial value of speed of the input shaft values, a maximum permissible torque value is obtained for the variable-speed drive in those work conditions; converting the maximum permissible torque value to a maximum permissible pressure value; and setting a degree of release and engagement of the clutch as a function of said torque transmission recorded on the variable-speed drive, wherein the controller compares a measured pressure value, and the maximum permissible pressure value and if the measured pressure value is greater than the maximum permissible pressure value, work pressure of the clutch is set to a theoretical value, which theoretically produces a pressure on the variable-speed drive lower than or at most equal to the maximum permissible pressure value; the clutch is therefore partly released and set to the theoretical pressure value and begins slipping and transmitting less torque to the variable-speed drive.