| 摘要 |
PROBLEM TO BE SOLVED: To prevent an automobile from reversing by prohibiting a shift down at starting time. SOLUTION: In an advancing condition of pulley ratio higher than the first pulley ratio in a gear neutral condition, the second pulley ratio is set. In the second pulley ratio or less, a movable sheave 7b of a primary pulley 7 is moved to an O/D side in the drawing. This moving amount is detected by a sensor shoe (detection means) 65 associated with the movable sheave 7b, a port (t) is closed by a ratio sensing valve (regulating means) 63 associated with the sensor shoe 65, and an oil pressure from a primary regulator valve 56 is stopped. In this way, supply of pressure oil, relating to the second pressure oil chamber 47 through a down shift relief valve 58, manual valve 59 and a low/high control valve 60, is stopped, and a down shift is prohibited. |
