Manual shift control device of a transmission control system for an

Abstract

A manual shift control device of a transmission control system for an automotive automatic transmission. A solenoid feed valve feeds line pressure passing through a pressure regulator valve to first, second and third solenoid valves. A torque control regulator valve changes drive pressure into torque pressure. A control switch valve alternatively feeds torque pressure to first and second torque pressure passages. An N-D control valve sequentially feeds torque pressure and drive pressure to a second friction member, which is applied at an initial shift operation together with a first friction member, to thereby alleviate shift shock from neutral range 'N' to drive range 'D'. A first-to-second speed shift valve feeds part of the torque pressure and part of the drive pressure to a third friction member during a shift operation from the first speed to the second speed. A second-to-third speed shift valve feeds part of the torque pressure as well as part of the hydraulic pressure to a fourth friction member during a shift operation from the second speed to the third speed. A third-to-fourth speed shift valve feeds part of the torque pressure as well as part of the hydraulic pressure fed to the fourth friction member and, at the same time, interrupts the hydraulic pressure feeding to the first friction member during a shift operation from the third speed to the fourth speed. The third-to-fourth speed shift valve feeds drive pressure to the seventh friction member when manual shifting from the fourth speed to the second speed of a second '2' range. An N-R control valve feeds hydraulic pressure to a sixth friction member during reverse 'R' range. A shock alleviator absorbs shift shock by the hydraulic pressure.