Vorrichtung und Verfahren zur Steuerung stufenloser Getriebe

摘要

The line hydraulic pressure setting portion (160) sets the line hydraulic pressure P L , which is the base pressure for the required shift control pressure Pin and the required belt clamping pressure Pd, based on the higher of the required pressures Pin and Pd. At this time, if the continuously variable transmission (18) is to be shifted up, the required Pin calculating portion (162) calculates the required shift control pressure Pin based on one of the target speed ratio ³* and the actual speed ratio ³ with which the required shift pressure Pv is calculated to be higher than with the other. As such, the required shift control pressure Pin is set to the minimum necessary level for shifting up the continuously variable transmission (18) and the line hydraulic pressure P L is appropriately set to a level for obtaining the required shift control pressure Pin.