| 摘要 |
PROBLEM TO BE SOLVED: To provide a hydraulic control system of an automatic transmission carrying out precise control of an operating hydraulic pressure supplied to a frictional element during shifting, and capable of fundamentally coping with oil leakage under a maximum operating hydraulic pressure. SOLUTION: The hydraulic control system of the automatic transmission for a vehicle controls and supplies a hydraulic pressure generated by an oil pump as the operating hydraulic pressure for the frictional element selectively operating at each shift ratio. A hydraulic line is configured such that the operating hydraulic pressure of the frictional element is controlled by a pressure control valve PCV and a switching valve SWV that are controlled by a solenoid valve SOL. An exhaust hydraulic line of the pressure control valve PCV is connected to an exhaust hydraulic line of the switching valve SWV such that the exhaust hydraulic line of the pressure control valve PCV can be controlled by a switching of the switching valve SWV. COPYRIGHT: (C)2006,JPO&NCIPI |
