SHIFT CONTROL UNIT FOR AUTOMATIC TRANSMISSION

摘要

PURPOSE:To prevent shift chock by providing a correcation means which corrects a running speed of a gear ratio shifting rate of an auxiliary transmission according to charge rate of rotation. CONSTITUTION:An auxiliary transmission 4 is feedback controlled by a feedback control means so that a gear ratio shifting rate Gs of the auxiliary transmission follows a specified target gear ratio shifting rate Gst which is set according to a gear ratio shifting rate Gm of a main transmission 3 at shifting to specified speed. Change rate DELTATrp of input rotation speed of a transmission AT is detected by a rotation change rate detection means. Running speed of the gear ratio shifting rate of the auxiliary transmission 4 is corrected by a correction means according to the detected rotation change rate DELTATrp. As a result, when the main transmission 3 and the auxiliary transmission 4 are shifted simultaneously, torque fluctuation under feedback control of the auxiliary transmission 4 can be prevented.