Continuously variable transmission and control method thereof

摘要

A continuously variable transmission includes a variator (20) capable of varying a speed ratio continuously, and a subtransmission mechanism (30) provided in series with the variator (20). When an actual through speed ratio passes a predetermined mode switch speed ratio, a transmission controller (12) performs a coordinated shift in which a gear position of the subtransmission mechanism (30) is changed and a speed ratio of the variator (20) is varied in an opposite direction to a speed ratio variation direction of the subtransmission mechanism (30). When the rapid deceleration is determined to be underway, the transmission controller (12) decreases a speed ratio variation amount of the variator (20) in the direction of a High side accompanied by a downshift of the subtransmission mechanism (30) compared with the coordinated shift.