| 摘要 |
PURPOSE:To keep off any ascending change in line pressure with the stop of cutback action at the time of gear shifting. CONSTITUTION:Hydraulic pressure in an oil passage 100 acts on a cutback valve 97 as control pressure. This oil passage 100 is interconnected to a 1-2 solenoid for selecting a 1-2 shift valve. At time of shift from 2 to 3, by way of example, the 1-2 solenoid is selected at one period at the shift transition duration, and if hydraulic pressure in the oil passage 100 is changed to a higher value, a right sol 97b of the cutback valve 97 is moved to the right, and an oil passage 99 being interconnected to a pressure reducing port 82b of a pressure regulator valve 82 is interconnected to a drain port 97e, so that a cutback function is brought to nothing, thus the regulator valve 82 tries to generate a higher line pressure. At this time, modulator pressure in a modulator valve 81 regulating pressure in the pressure regulator valve 82 is controlled to be lowered by a duty solenoid SOL. Therefore, the line pressure will not go up at all, thus it is kept to the specified value. |
