Patent Number: 6,309,324

Title: Automatic transmission control system

Abstract: An automatic transmission control system provided with a speed sensor formonitoring an input speed to the automatic transmission, on one hand,prohibits gear shifts only to gears which are provided by alternatelylocking and unlocking two friction coupling elements at a timingdetermined essentially based on an input speed when an failure of thespeed sensor occurs and, on the other hand, permits gear shifts to gearswhich are provided in participation of the one-way clutch by alternatelylocking and unlocking the two friction coupling elements, a timelyalternate lock and unlock operation of the two friction coupling elementsbeing spontaneously caused by the unlock operation of one of the twofriction coupling elements and gear shifts to gears which are provided bylocking one of the two friction coupling elements and unlocking the otherwith common pressure or unlocking one of the two friction couplingelements and locking the other with common pressure.

Inventors: Sawa; Kenji (Hiroshima, JP), Kamada; Shinya (Hiroshima, JP)

Assignee:

International Classification:

Expiration Date: 10/32013