| 摘要 |
PROBLEM TO BE SOLVED: To provide a control device for an automatic transmission capable of controlling applied hydraulic pressure to a friction element even when modulatory pressure excessively rises due to failure or the like. SOLUTION: In this control device for an automatic transmission, engagement and release of a plurality of friction elements 1-6 are controlled by hydraulic pressure of working fluid. It is provided with a modulatory pressure generating means 45 to reduce line pressure as an original pressure of the applied hydraulic pressure to the friction elements 2-6, and generate the modulatory pressure, solenoid valves 12, 18, 23, 28, and 34 to generate a command pressure based on the modulatory pressure as an original pressure, pressure control valves 10, 16, 20, 26, and 32 to control the applied hydraulic pressure to the friction elements 2-6 in accordance with the command pressure, and a pressure reducing means 46 to reduce the modulatory pressure when the modulatory pressure reaches its upper limit value. COPYRIGHT: (C)2003,JPO |
