초록 ▼

A control system and method for a power delivery system, such as in an automotive vehicle, having an engine coupled to a continuously variable ratio transmission (CVT). Totally independent control of engine and transmission enable the engine to precisely follow a desired operating characteristic, su

A control system and method for a power delivery system, such as in an automotive vehicle, having an engine coupled to a continuously variable ratio transmission (CVT). Totally independent control of engine and transmission enable the engine to precisely follow a desired operating characteristic, such as the ideal operating line for low fuel consumption. CVT ratio is controlled as a function of commanded desired system performance (e.g., power or torque) and measured actual system performance, such as CVT torque output, while engine fuel requirements (e.g., throttle position) are strictly a function of measured engine speed. Fuel requirements are therefore precisely adjusted in accordance with the ideal characteristics for any load placed on the engine. Appropriate controls prevent anomalous engine and vehicle behavior, and allow for transient start-up from rest. In a preferred embodiment a proportional controller is used to set the driving diameter of the driver sheave of a V-belt traction drive CVT, while the drive diameter of the driven sheave is controlled by a torque ramp.

대표청구항 ▼

A method of controlling the operation of a power delivery system including a prime mover and a continuously variable ratio transmission coupled to said prime mover for delivering power from said prime mover to an output shaft, said transmission having adjustable driver means operatively coupled to s

A method of controlling the operation of a power delivery system including a prime mover and a continuously variable ratio transmission coupled to said prime mover for delivering power from said prime mover to an output shaft, said transmission having adjustable driver means operatively coupled to said prime mover for adjustably transmitting power from said prime mover, and adjustable driven means operatively coupled to said driver means and to said output shaft for adjustably transmitting power from said driver means to said output shaft, the ratio of said transmission being determined by the relative adjustments of said driver means and said driven means, said prime mover having fuel delivery means for delivering a variable quantity of fuel thereto, said power delivery system being controlled by command means for commanding a desired system performance, the method comprising the steps of: measuring the actual performance of the power delivery system; controlling the ratio of said transmission as a function of the desired system performance commanded by said command means and said measured actual system performance, the speed of said prime mover varying as a function of transmission ratio, the step of controlling the transmission ratio comprising: controlling the adjustment of said driver means as a function of the desired system performance commanded by said command means; and controlling the adjustment of said driven means as a function of said measured actual system performance; predetermining a fuel function defining desired fuel requirements for said prime mover in relation to prime mover operating speed; measuring the speed of said prime mover; and controlling said fuel delivery means only in accordance with said fuel function so that the quantity of fuel delivered to said prime mover is determined only by the speed thereof.