| 摘要 |
PURPOSE:To prevent the inadvertent shift-down of a sub speed change gear during high-speed traveling by installing a means for holding a shift valve at high speed stage independently of electric control signals in a prescribed range, in the combination of a continuously variable transmission and an auxiliary speed change gear in two advance stages. CONSTITUTION:An auxiliary speed change gear in two advance stages is installed onto the output shaft side of a continuously variable transmission, and the speed change stages are switched by a shift valve 250, and said auxiliary speed change gear is equipped with a high-speed clutch 56 for generating engagement state when pressurized oil is supplied in high speed stage and a low-speed clutch 58 for generating engagement state at low-speed stage. The shift valve 250 is equipped with a control port 264 into which the line pressure is introduced in D range through a manual valve, and operates to hold the valve 250 at the high-speed stage position under the line pressure at the high-speed stage position. Further, a solenoid valve 278 for controlling the position of the shift valve 250 is provided. |
