VORRICHTUNG ZUM STEUERN DES DREHMOMENTVERHAELTNISSES EINES STUFENLOSEN KEILRIEMENGETRIEBES FUER KRAFTFAHRZEUGE

摘要

In a V-belt type continuously variable transmission for vehicles, the line pressure is supplied to a hydraulic servo system of the output pulley, while the pressure to a hydraulic servo system of the input pulley is regulated by a torque ratio control device. The torque ratio control device of the invention comprises an electric control circuit receiving input signals of the vehicle running conditions such as the throttle opening, the vehicle speed or the input pulley revolution speed and generating output signals to control the effective diameter of the input pulley, two electromagnetic solenoid valves controlled by the output signals of the electric control circuit, and a torque ratio control valve controlled by the two solenoid valves and regulating the hydraulic pressure supplied to the hydraulic servo system of the input pulley. The output hydraulic pressure of the torque ratio control device is supplied to the hydraulic servo system of the input pulley thereby continuously variable shifting is effected.