| 摘要 |
PURPOSE:To obtain a good speed change response by providing a bypath having a switching valve between respective hydraulic paths for feeding line pressure oil to primary and secondary pulleys and intake/discharge oil paths for a speed change control valve, thereby feeding/discharging line pressure quickly. CONSTITUTION:A spool 68 in a speed change control valve 44 is switched to the right and left so as to feed/discharge a predetermined line oil pressure to hydraulic cylinders 26, 28 for primary and secondary pulleys 20, 22 of a continuously variable transmission (CVT) thus making a CVT control. Bypaths 110, 112, 114, 116 are provided through switching valves 118, 120 between respective oil paths 29, 30 to hydraulic cylinders of respective pulleys and suction/ discharge oil paths 50, 52 for the speed change control valve 44. When the speed change ratio of CVT is increased, the switching valve 118 is operated to feed line pressure quickly to the hydraulic cylinder 26 for the primary pulley 20 so as to achieve a good and quick speed change response.
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