Hydraulische Steuerung für ein stufenloses Fahrzeuggetriebe mit zwei je nach Schalthebel Position aktivierbaren Schaltventilen.

摘要

A hydraulic control apparatus for controlling a vehicle continuously variable transmission (14) having a clutch device (16) disposed in series with the transmission in a power transmitting line, to disconnect the power transmitting line when a shift lever is placed in a neutral position. The apparatus includes a first shift control valve (330, 460, 490) for producing a first output for changing the speed ratio, based on a required output pressure corresponding to the currently required vehicle acceleration value, and a first input shaft speed corresponding to the transmission input shaft speed, a second shift control valve device (332) for producing a second output for changing the speed ratio, based on a second input shaft speed pressure and an output shaft speed pressure corresponding to the input and output shaft speeds of the clutch device, respectively, so as to reduce a difference between the speeds of the input and output shafts of the reversing device, and a switching valve device (328) for applying the first and second outputs to the transmission when the shift lever is operated to the drive and neutral positions, respectively.