| 摘要 |
PROBLEM TO BE SOLVED: To prevent the excessive rotation of an engine while utilizing the low pulley control oil pressure so as to enable a high-speed stage in the case where a failure is generated. SOLUTION: A belt type continuously variable transmission is formed of a driving and a driven movable pulleys 11, 16, a metal V-shaped belt stretched between them, and a driving and a driven cylinder chambers 14, 19 for controlling width of both the pulleys. In this case, a hydraulic control device for controlling speed change is formed of a first control valve (a first linear solenoid valve 41 and a first pulley control valve 43) for setting the first control oil pressure to be supplied to the driving cylinder 14, a second control valve (a second linear solenoid valve 45 and a second pulley control valve 47) for setting the second control oil pressure to be supplied to the driven cylinder chamber 19, and a switching valve 50 to be operated by the oil pressure generated when electrifying is cut by a failure of the first linear solenoid valve 41 so as to lower the maximum oil pressure of the second control oil pressure by the second control valve. |
