| 摘要 |
PURPOSE:To promote the efficiency of oil pressure and the decrease of surge pressure at the time of gear shift by outputting a valve closing signal to a main solenoid valve first at the time of terminating gear shift, and after the lapse of the specified time, outputting a valve opening signal to auxiliary solenoid valves. CONSTITUTION:A controller 17 opens a main solenoid valve VM in the case of performing gear shift from backward to forward, and in the valve closed state of an auxiliary solenoid valve VF on and the valve opened state of an auxiliary solenoid valve VR off, supplies operating oil from an accumulator 15 into the rod chamber R1 of a gear shift cylinder 8 and discharges operating oil in a bottom chamber R2 into a tank 12. At the time of terminating gear shift, the auxiliary solenoid valve VR is switched on to be closed, then the main solenoid valve VM is switched on to be closed, and after the lapse of the spacified time, the auxiliary solenoid valves VF, VR are switched off to be opened, thus promoting the efficiency of oil pressure and the decrease of surge pressure at the time of gear shift due to dispersion in the responsiveness of each solenoid valve. |
