| 摘要 |
PROBLEM TO BE SOLVED: To provide a hydraulic control device of an automatic transmission capable of reducing a shift shock at down shift time and capable of performing highly accurate learning of an engaging side frictionally engaging element on the basis of a change in an input shaft rotating speed. SOLUTION: This hydraulic control device is provided with driving force transmission control means 21a, 21b for controlling torque input from the engine side by controlling a connecting state between an input shaft and an output shaft by a brake B1 at down shift time and a shift progress control means 21c for controlling so as to cut off the connecting state after maintaining the connecting state of the input shaft and the output shaft by the driving force transmission control means until rotational accelerationΔN of the input shaft exceeds 0 at down shift time. Learning of a stroke of an engaging side brake B5 using an input shaft rotation change as an index can be performed by using connecting time. Afterwards, down shift operation is actually performed, and since the connecting state between the input shaft and the output shaft is cut off when an engaging side frictionally engaging element actually starts engagement, a shift mechanism is put in a freely rotating state to reduce a shift shock.
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