Patent ID: 10207714

Abstract:
Control device for continuously variable transmission has continuously variable transmission mechanism (CVT) transmitting power with belt (7) wound around primary and secondary pulley (5, 6); torque convertor (2) having pump impeller (20), turbine runner (21) and lock-up clutch (2a); and control unit (10) controlling lock-up clutch (2a) to predetermined engagement state and controlling the CVT to predetermined transmission ratio, according to travelling condition. Control unit (10) is configured to, when shifting lock-up clutch (2a) from disengagement to engagement state, control transmission ratio of CVT so that when rotation speed difference (ΔN) between engine speed (Ne) and turbine speed (Nt) that is rotation speed of turbine runner is predetermined rotation speed difference (ΔN1) or less, turbine speed (Nt) approaches engine speed (Ne) more than turbine speed (Nt1) of case where control of transmission ratio of CVT, which is set according to travelling condition during shift of lock-up clutch (2a), is continued.