Continuously variable transmission system for vehicle

摘要

A rotation ratio of a continuously variable transmission for a vehicle provided with a pair of variable pulleys whereof the diameter of a contact part with a V-belt is made to vary according to an oil pressure, is controlled according to the running state of a vehicle. An oil pressure control valve is therefore provided to control the oil pressure. A rotation ratio command value is computed from a target rotation ratio set according to the vehicle running state and a control variable set for each rotation ratio according to the dynamic characteristics of the transmission. By inputting a signal based on this rotation ratio command value to the oil pressure control valve, a desirable speed change response is obtained.