| 摘要 |
<p>In a twin-clutch transmission, when a third shift valve (for example) goes out of order and the shift change accordingly becomes incapable of being carried out, the hydraulic pressure outputted from the third shift valve is controlled by a fourth shift valve operated by a first shift solenoid for a first shift valve. Accordingly, the hydraulic pressure outputted by a second linear solenoid is supplied to one of second hydraulic actuators, thereby enabling one of second predetermined transmission gear stages to be pre-shifted by use of a second power transmission path. When the first shift valve is used as a fail-safe, it is possible for the vehicle to make a minimum necessary run by setting up one of the second predetermined transmission gear stages. Furthermore, the fourth shift valve is driven by use of the existing first shift solenoid, thus minimizing the number of parts and cost.</p> |
