Patent ID: 6393928
Filing Date: 2002-05-28
Classification: F16H,Y10T

Abstract:
A control device for a synchronous mesh automatic transmission that automatically changes a plurality of gear stages, said control device comprising:an input shaft; an output shaft; a plurality of speed-changing gear trains for transmitting a rotation of said input shaft to said output shaft while changing a speed of rotation of said output shaft; a shift gear for selecting one of said plurality of speed-changing gear trains, and transmitting power from said input shaft to said output shaft through the one selected speed-changing gear train; a shift actuator for driving said shift gear; a shift position sensor for detecting a shift position of said shift gear; an input shaft rotational speed sensor for detecting a rotational speed of said input shaft; an output shaft rotational speed sensor for detecting a rotational speed of said output shaft; and a control unit for learning and correcting, during a gear changing operation of said shift gear caused by said shift actuator, a value of a synchronization starting shift position of said shift gear based on an output of said shift position sensor, and based on a relationship among a gear ratio, the rotational speed of said transmission input shaft detected by said input shaft rotational speed sensor, and the rotational speed of the transmission output shaft detected by said output shaft rotational speed sensor, wherein an initial value of said synchronization starting shift position value is set based on learned values of a shift neutral position and a shift completion position of said shift gear learned by said control unit.