| 摘要 |
PROBLEM TO BE SOLVED: To simplify a structure of an unit by decreasing the number of control valves, hydraulic switches, solenoid valves and the like as far as possible. SOLUTION: In a transmission mechanism TM, wherein a 2nd-speed gear train 12 is arranged by engaging with a 2nd-speed clutch 22, a 3rd-speed gear train 13 is arranged by engaging with a 3rd-speed clutch 23, and a 4th-speed gear train 14 is arranged by engaging with a 4-R clutch 24, a 2nd control valve 70 in the control unit is located at a releasing position for interconnecting the 2nd-speed clutch 22 to a drain side by receiving interlinking hydraulic oil supplied to the 3rd-speed clutch 23 or the 4th-speed clutch 24. The control valve 70 is also located at a supply position for interconnecting the 2nd-speed clutch 22 to a line hydraulic oil passage when the hydraulic oil is supplied to the 2nd-speed clutch 22. Further, when a gear change from 3rd-speed to 2nd-speed or 4th-speed to 2nd-speed is performed by engaging with the 2nd-speed clutch in a connected state in which the 3rd-speed clutch or 4th-speed clutch is engaged, the 2nd control valve is kept to locate at the supply position by acting line pressure (valve position setting hydraulic oil) on the 2nd control valve. COPYRIGHT: (C)2004,JPO |
