TRANSMISSION RATIO CONTROL SYSTEM FOR A CONTINUOUSLY VARIABLE TRANSMISSION

摘要

A control system has a transmission ratio control valve having a spool for controlling oil supplied to a cylinder of a drive pulley to change the transmission ratio. By controlling the pressure of oil supplied to one end of the spool of the transmission ratio control valve in accordance with conditions of the engine and transmission, the spool is shifted, so that the rate of change of the transmission ratio is controlled. Actual rate of change of the transmission ratio is compared with a desired rate of change to produce an error signal. In response to the error signal, the actual rate of change is converged to the desired rate of change.