| 摘要 |
PURPOSE:To exactly ensure the operation of stepless change gear by a method in which an oil path is opened by the sliding movement of the main spool valve, a mobile pulley halve is moved back and forth, and then the oil path is closed by the sliding movement of a coaxial follow spool valve according to the sliding amount of the main spool valve. CONSTITUTION:When moving a shifter 132 to the left, the main spool valve 70 moves to the left, a throught hole 94 is opened, a right-handed oil supply groove 82 is lead to a right-handed oil grooves 87, and an oil discharge port 95 is closed by the main spool valve 70. Whereupon, since working oil pressure in a cylindrical oil path 74 is introduced even into the second oil pressure chamber 502, a piston 49 receives a differential oil pressure, and begins to move to the left, whereby advancing a mobile pulley halve 47. By this, a follow spool valves 71 also moves through an interlocking piston 96 at the same time to pursue the main spool valve 70, the through hole 94 and the oil discharge port 95 are closed by the main spool valve 70, and in the second oil pressure chamber 502, when the cylindrical oil path 74 or the oil discharge port 95 is interrupted, the movement of the mobile pulley halve 47 is stopped following the piston 49. |
