Apparatus for reducing pressure of frictional coupling device of vehicle automatic transmission upon shifting to non-drive position

Abstract

An apparatus for controlling an automatic transmission of a motor vehicle which is shifted to a non-drive position with a releasing action of a hydraulically operated frictional coupling clutch upon operation of a manually operated member from a drive position to a non-drive position, the apparatus including a non-drive shift detecting device for detecting a non-drive shifting operation of the manually operated member from the drive position to the non-drive position, a rapid pressure reduction device operated upon detection of the non-drive shifting operation for rapidly reducing a pressure of the hydraulically operated frictional coupling device to a predetermined pressure level, and a continuous pressure reduction device for continuously reducing the pressure of the frictional coupling device from the predetermined pressure level at a predetermined reduction rate.

Dependencies are inferred from the claim text.