| 摘要 |
PURPOSE:To improve fuel expenses by opening a lock up clutch at the first speed step, and operating the lock up clutch when designated conditions are satisfied at all speed change steps above the second speed step. CONSTITUTION:In the above device having a torque converter 20 with a lock up clutch 24, and having no frictional engagement device which is not engaged at the first speed step and engaged at all speed change steps above the second speed step, there is newly provided a switch valve 100 with a spool 106 having two lands 102,104 different in face area. The switch valve 100 is adapted to connect an oil path 114 diverging from the upstream of an orifice 112 of an oil path 110 leading to an overdrive brake B to the first input port 108, connect an oil path 122 diverging from the upstream of an orifice 120 of an oil path 118 leading to a second brake B to the second input port 116, and connect output ports 124, 128 to an input port 202 of a signal valve 200. |
