| 摘要 |
PURPOSE:To eliminate the feeling of physical disorder at the time of speed change in down shift during the engine brake command by releasing the fastening delay of other friction element if the speed change is accompanied with the engine brake command at the time of speed change in down shift. CONSTITUTION:The reduction brake pressure PRD/S is supplied to perform, eliminating the direct clutch pressure PD/C. For example, at the time of speed change of 4 3, if the automatic variable speed range is normal, an orifice cancel valve 18 cut off a by-pass circuit 17, and a one way orifice 16 controls the rising speed so as to delay the fastening. But if the speed change in 4 3 down shift is accompanied with the engine brake command, the orifice cancel valve 18 opens the by-pass circuit 17 with the III range pressure PIII, and the reduction brake pressure rises quickly so as to quickly fasten the reduction brake RD/B. Consequently, the speed change in down shift is performed without the engagement of the reduction one way clutch RD/OWC, and the feeling of physical disorder generated by the delay of engine brake after the speed change can be eliminated. |
