Patent ID: 7735388

Claim:
A control system for an automatic transmission having: an input shaft adapted to receive torque from a driving force source and rotate thereby; an output shaft for output of torque to a driving shaft of a vehicle; a plurality of gears adapted to rotate in synchronism with the input shaft and/or the output shaft; a plurality of free rotatable gears meshing with said gears; a plurality of sleeves adapted to rotate in synchronism with the input shaft and/or the output shaft and slidable axially; and a balk ring disposed between the free rotatable gears and the sleeves, wherein the balk ring is pushed against any of the free rotatable gears by movement of any of the sleeves, thereby synchronizing rotation of the sleeve with that of the free rotatable gear, and the sleeve and the free rotatable gear are brought into mesh with each other by further movement of the sleeve to attain a predetermined shift range, the control system comprising: balk abutment determining means for determining whether the sleeve stays within a balk abutment range for a predetermined time or not; and pushing load increasing means for increasing a pushing load for the sleeve when it is determined by the balk abutment determining means that the sleeve stays within the balk abutment range for the predetermined time.