| 摘要 |
PROBLEM TO BE SOLVED: To accurately estimate a residual oil quantity of a frictional engaging element (for example, a friction clutch and a brake). SOLUTION: A linear solenoid valve for adjusting hydraulic pressure is arranged in a hydraulic control valve HCV for controlling hydraulic pressure supply to the clutch so as to perform a prescribed shift according to shift indication, and the residual oil quantity in the clutch is estimated from indicating hydraulic pressure to the linear solenoid valve. At this time, when the indicating hydraulic pressure is higher than a first prescribed value, the residual oil quantity is estimated as a full oil quantity. When the indicating hydraulic pressure is hydraulic pressure up to a second prescribed value of pressure lower than this value from a first prescribed value, an oil quantity calculated by reducing an oil quantity when becoming less than the first prescribed value up to a lower limit oil quantity QL at a prescribed rate, is estimated as the residual oil quantity. When the indicating hydraulic pressure becomes pressure lower than the second prescribed value, the oil quantity calculated by reducing at the prescribed rate up to reaching an empty oil quantity by exceeding the lower limit oil quantity, is estimated as the residual oil quantity. COPYRIGHT: (C)2004,JPO |
