| 摘要 |
<P>PROBLEM TO BE SOLVED: To assure a minimum running performance and allow a start after stoppage even when magnetic selector valves 68a and 68b cannot be changed over due to the failure of a power supply during a high speed running. <P>SOLUTION: When this transmission fails in a state that the normal forward range D of a manual hydraulic selector valve 71 is selected, an emergency selector valve 76 is changed over to a state reverse to a shown state by the stopping of a hydraulic pressure led from a shuttle valve 79. Then, the hydraulic pressure is introduced into a clutch 40a for high speed, and the hydraulic pressure is discharged from a clutch 39a for low speed to establish a high speed mode. Accordingly, a braking force can be prevented from abruptly occurring based on an engine brake to assure a safety during the high speed running. In addition, when the manual hydraulic selector valve 71 is set to a low speed running range L or a reverse range R, the start of the engine and the start and low speed running of a vehicle are allowed. <P>COPYRIGHT: (C)2004,JPO |
