Einrichtung zur Einstellung der Getriebeübersetzung für kontinuierlich verstellbares Getriebe (CVT)

摘要

A speed change ratio of a continuously variable transmission (17) comprising a V-belt (24) looped around a pair of variable pulleys (16,26) for varying the speed change ratio according to a first and second oil pressures. A speed change control valve (63) converts a first oil pressure from an oil pressure supply unit (6) to a second oil pressure based on a speed change ratio command value. The speed change ratio command value is calculated by a microprocessor (1) according to a real speed change ratio and dynamic characteristics of the transmission. By calculating the dynamic characteristics according to the real speed change ratio and the first oil pressure, a set response of the transmission is always obtained regardless of fluctuations of the first oil pressure.