| 摘要 |
<p>PURPOSE:To aim at enhancing the control ability of an automatic speed change unit and as well at making compact thereof, by utilizing a small accumulator to delay the rise of hydraulic pressure for a long time. CONSTITUTION:A spool valve 460 constituting a mechanism for the rise of hydraulic pressure and disposed between a hydraulic pressure source and a hydraulic servo, is subjected from above to the feed-back of the output pressure Po of an output oil passage 1Q, and is communicated from below with the output oil passage 1Q through a constriction 480. In addition, there is provided a spool 471 for adjusting the communication between an inport 481 which receives an accumulator pressure Pa from an accumulator 490 through an oil passage 1R and communicates with the hydraulic pressure source through an oil passage 1Q, and an output port 483 which communicates with the output passage 1Q. Further, since the hydraulic servo is directly communicated without through the constriction 480, and therefore the size of the constriction 480 is made small to a desired value, thereby the adjustment of rise of hydraulic pressure may be made over a long time even though the capacity of the accumulator 490 is small.</p> |
