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A hydraulic apparatus for a continuously variable transmission by which the rate of changing speed ratios between a driving pulley and a driven pulley is consecutively varied. The apparatus includes a ratio selecting apparatus for changing the speed ratios and a change speed control apparatus for co

A hydraulic apparatus for a continuously variable transmission by which the rate of changing speed ratios between a driving pulley and a driven pulley is consecutively varied. The apparatus includes a ratio selecting apparatus for changing the speed ratios and a change speed control apparatus for controlling the rate of change of the CVT transmission. The rate of changing the speed ratios is varied by controlling the amount of hydraulic fluid drained through the change speed control apparatus from a hydraulic cylinder, whose pressure is applied to the driving pulley.

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A hydraulic apparatus for a continuously variable transmission for motor vehicles having a driving pulley with a fixed member and a movable member, the movable member being actuated by a hydraulic cylinder to form a V-shaped opening therebetween, a driven pulley with another fixed member and another

A hydraulic apparatus for a continuously variable transmission for motor vehicles having a driving pulley with a fixed member and a movable member, the movable member being actuated by a hydraulic cylinder to form a V-shaped opening therebetween, a driven pulley with another fixed member and another movable member, said another movable member being similarly actuated by another hydraulic cylinder to form another V-shaped opening therebetween, and a belt member spanning said pulleys, comprising: a hydraulic fluid reservoir containing hydraulic fluid; a hydraulic fluid pump for pumping the hydraulic fluid from the reservoir; ratio selecting valve means for changing the speed ratio between the driving pulley and the driven pulley; and change speed control valve means for controlling the speed of changing speed ratios between the driving pulley and the driven pulley, the change speed control means comprising; a valve having a first and a second land; a first inlet passage supplied with the hydraulic fluid from the hydraulic fluid pump; a second inlet passage supplied with the hydraulic fluid from the hydraulic fluid pump, the hydraulic fluid being exerted on the second land; a controlling means connected with the second inlet passage, the controlling means supplying the hydraulic fluid to the second land or draining the hydraulic fluid in the second inlet passage; an outlet passage connected with the cylinder of the driving pulley, the outlet passage draining the fluid of the cylinder of the driving pulley therethrough when the hydraulic fluid is not supplied to the second land, or being disconnected with the first inlet passage when the hydraulic fluid is not supplied to the second land; and a first biasing means for biasing the first land in the direction to communicate the first inlet passage with the outlet passage.