Patent ID: 8571768

Claim:
A control device for a vehicle continuously variable transmission comprising: a continuously variable transmission mechanism having a speed ratio that can he modified continuously; and a subtransmission mechanism provided in series with the continuously variable transmission mechanism, including a first gear position and a second gear position, the second gear position having a smaller speed ratio than the first gear position, as forward gear positions, and switching between the first gear position and the second gear position by engaging or disengaging a plurality of frictional engagement elements selectively, wherein the control device comprises a transmission controller programmed to: set an overall speed ratio of the continuously variable transmission mechanism and the subtransmission mechanism reachable on the basis of an operating condition of the vehicle as a final speed ratio; control the continuously variable transmission mechanism and the subtransmission mechanism such that the overall speed ratio aligns with the final speed ratio at a predetermined transient response; determine whether a stagnation period in which the overall speed ratio stops varying will occur during an upshift; and after determining that the stagnation period will occur, shorten time required to advance to an inertia phase from commencement of shifting in the subtransmission mechanism.