CONTROLLER FOR CONTINUOUSLY VARIABLE TRANSMISSION

摘要

PURPOSE:To prevent overrun by carrying out speed change control of a continuously variable transmission and mode control of an auxiliary transmission through a judging means based on a differential signal between rotation under L-shift and a limit rotation fed from a rotation comparing means and a signal fed from a target torque ratio setting means. CONSTITUTION:A continuously variable transmission 12 carries out speed change with large torque ratio width through continuously variable speed change of a belt type continuously variable transmission 30 and low/high speed mode switching control of an auxiliary transmission 20. A setting means 113 sets a target torque ratio corresponding to running condition, and a judging means 115 carries out low/high mode switching control of the auxiliary transmission through a switching means 110 based on a difference between a limit rotation of a setting means 104 fed from a rotation comparing means 124 and rotation under L-shift fed from a calculating means 118 and a mode fed from a detecting means 112 thus carrying out continuously variable speed change control by means of the continuously variable transmission 30 through an operating means 100. Consequently, speed change operation can be made quickly without causing overrun.