CONTROL DEVICE OF CONTINUOUSLY VARIABLE TRANSMISSION MECHANISM

PROBLEM TO BE SOLVED: To provide a control device of a continuously variable transmission mechanism, capable of effectively suppressing an increase in temperature of the continuously variable transmission mechanism with simple control.SOLUTION: A control device of a toroidal continuously variable transmission mechanism (5) can continuously change a speed ratio with transfer elements (51, 52, 53) which transfer driving force between an input shaft (2) and an output shaft (3). The device estimates temperatures on toroidal surfaces (51b, 52b) of the continuously variable transmission mechanism (5), and performs controls of changing a target ratio of the continuously variable transmission mechanism (5) to a ratio having higher mechanical efficiency of power transmission than at present on the basis of a relationship between a prestored ratio of the continuously variable transmission mechanism (5) and the mechanical efficiency of power transmission when the estimated temperatures (TS) are determined to be higher than a predetermined temperature (T0) at which transmission torque (μmax) that can be transmitted via the toroidal surfaces (51b, 52b) becomes a predetermined value (μ0) or lower from a relationship between temperatures (T) of the toroidal surfaces (51b, 52b) and the transmission torque (μmax).