| 摘要 |
PURPOSE:To prevent the excessive increase of the friction force between a transmission belt and a variable pulley by forming a pressure receiving surface onto which the hydraulic pressure of a hydraulic cylinder acts onto a movable rotary body of the variable pulley and forming a pressure receiving surface for compensation in the opposite direction. CONSTITUTION:A disc-shaped partitioning plate 84 which contacts in slidable ways with a movable rotary body 76 forms a hydraulic chamber 84 forming an annular space between a fixed rotary body 68. A hydraulic chamber 98 forming an annular space is formed also between the partitioning plate 84 and an installation member 66. Said hydraulic chamber 98 forms an annular space for compensation which compensates the increased-pressure portion due to the centrifugal force acting onto the working oil in the hydraulic chamber 86, and the edge surface 112 forms a pressure receiving surface for compensation onto which the hydraulic pressure in the hydraulic chamber 98 acts. Though the hydraulic pressure in the hydraulic chamber 98 acts not only onto the edge surface of the partitioning plate 84 but onto the edge surface of a cylindrical part 72, this part is opened through a hole 110, and a hydraulic pressure is hardly generated. |
