Continuously-variable transmission for vehicle

A continuously-variable transmission for a vehicle, comprising:

• a belt-type continuously-variable transmitting mechanism connected to a drive source and configured to continuously vary a speed ratio of the belt-type continuously-variable transmitting mechanism;
• an auxiliary transmitting mechanism provided in series with the belt-type continuously-variable transmitting mechanism and configured to attain a plurality of shift steps for a forward running of the vehicle;
• and
• a speed-increasing gear mechanism provided upstream from the auxiliary transmitting mechanism and configured to increase an input rotational speed of the auxiliary transmitting mechanism,
• wherein the speed-increasing gear mechanism is configured to set a speed increasing ratio of the speed-increasing gear mechanism at a value between an upper limit value and a lower limit value in accordance with a required performance,
• wherein the upper limit value is a speed-increasing-ratio value at which it begins to be judged that a power performance is reduced when the speed increasing ratio is further increased, and
• wherein the lower limit value is a speed-increasing-ratio value at which it begins to be judged that a suppressing effect of pull-in shock is reduced when the second speed-increasing-ratio is further lowered.