| 摘要 |
PURPOSE:To eliminate the delay of engine brake operation by so providing a bypass circuit opening in an engine brake range or a backward travel range as to be in parallel to an orifice for limiting the fluid oil pressure rise rate of a low-speed select friction element. CONSTITUTION:In shifting a sub-transmission via the coupling of a low-speed select friction element RD/B so provided as to be in parallel to a one-way clutch, the coupling pressure is gradually raised for normal drive and quickly raised for reverse drive or reverse rotation output via the interruption and continuity of a bypass valve 163 with a reduction timing valve 66. In the ordinary drive, therefore, the RD/B is coupled without any shock after releasing a high-speed select friction element D/C and then the engagement of the one-way clutch. On the other hand, during the reverse drive (engine brake) or reverse rotation output (backward travel), the operation of RD/B is synchronized with the releasing of D/C and quickly coupled. According to the aforesaid construction, a delay in the effectiveness of the engine brake can be prevented. |
