Method and apparatus for controlling reduction ratio of continuously variable transmission with engine coolant temperature compensation

摘要

A method and an apparatus for controlling the reduction ratio of a continuously variable transmission are disclosed wherein when an actual engine coolant temperature indicative signal is greater than or equal to a predetermined value indicative signal, a desired optimum reduction ratio signal is obtained by retrieving the desired optimum reduction ratio signal data stored in a memory versus an engine load and a vehicle speed. When the actual engine coolant temperature indicative signal is less than the predetermined value indicatiive signal, the same desired optimum reduction ratio signal data are retrieved based on a corrected signal which is obtained by correcting an engine load indicative signal or a vehicle speed indicative signal in order to provide a larger reduction ratio. Alternatively, another optimum reduction ratio signal data are retrieved when the actual engine coolant temperature indicative signal is less than the predetermined value indicative signal.