Patent ID: 8360907

Claim:
A hydraulic control system that is applied to a belt-type continuously variable transmission that includes a drive pulley and a driven pulley, around which a belt is wound, and that changes the belt turning radii of the pulleys on the basis of sheave pressures applied respectively to the pulleys to shift gears, wherein the hydraulic control system performs hydraulic control to regulate the sheave pressures, the hydraulic control system comprising: a first sheave pressure regulating valve that regulates a line pressure, the first sheave pressure regulating valve used for the hydraulic control as a source pressure, to obtain a first sheave pressure, which is one of the sheave pressures; and a fail-safe valve that selects and outputs any one of the first sheave pressure and a fail-safe hydraulic pressure to one of the pulleys; and an orifice that is provided in an oil passage between the fail-safe valve and the one of the pulleys, wherein a hydraulic pressure in the oil passage on the one of the pulleys side of the orifice is supplied to the first sheave pressure regulating valve as a feedback pressure.