TORQUE AND SPEED CONTROL IN A MACHINE WITH CONTINUOUSLY VARIABLE TRANSMISSION

摘要

A method regulates the torque output (252) and/or speed output (254) of a continuously variable transmission (CVT) (110) in a manner that may simulate a clutch. The CVT (110) may be incorporated in a machine (100) and maybe operatively coupled to a power source (106) and to a propulsion device (104). The method utilizes an unaltered torque-to-speed curve (256) that relates the torque output (252) to the speed output (254) of the CVT (110). The method may receive an operator input signal (310) indicating a desire to change operation of the machine (110). The torque-to-speed curve (256) may be shifted in response to the operator input signal (310) to limit the torque output available. In an aspect, an under-run curve (260) may be applied to the torque-to-speed curve (256), the under-run curve (260) corresponding to a target speed (262). The operator input signal (310) may also shift the under-run curve (260) to reduce the target speed (262).