Patent ID: 7303503

Claim:
A toroidal-type continuously variable transmission comprising: first and second disks respectively including inner surfaces and disposed so as to be concentric with each other; a plurality of power rollers which are interposed between and held by the mutually facing inner surface of the first and second disks and transmits force between the first and second disks; a support member swingable and shiftable about a pivot shaft in transmission with the power rollers rotatably supported; an actuator of an oil pressure type including a cylinder, a piston and a pair of oil pressure chambers separated by the piston, and which shifts the support member in the axial direction of the pivot shaft in accordance with supply and exclusion of the pressure oil in the pair of oil pressure chambers; a pressing device pressing the first disk toward the second disk in accordance with a pressing oil pressure; a control unit that electrically finds an optimum value of a pressing force to be generated by the pressing device according to the transmission ratio between the first and second disks; a first valve into which pressures in the pair of pressure chambers are inputted and which outputs a differential pressure in accordance with a difference between the pressure in the pair of pressure chambers; a correction valve which outputs a correction pressure determined in accordance with the optimum value found by the control unit; and a second valve into which the differential pressure outputted from the first valve and the correction pressure outputted from the correction valve, and which introduces, into the pressing device, the pressing oil pressure in accordance with the input.