Patent ID: 6544139
Filing Date: 2003-04-08
Classification: F16H

Abstract:
An electronic-hydraulic control device of an automatic automobile transmission with hydraulically engageable and releasable friction clutches or brakes (A, B, C, D, E) used to select individual gears, their actuators each having a control valve (20, 21, 23, 30) with a microprocessor control device by means of which, depending on the operating parameters of the automobile transmission and a drive motor as well as of a device for influencing at least one of a shifting program and a driving program, the electrical operation of a solenoid valve (12) and of pressure control valves (6, 7, 8, 9, 10, 11) can be adjusted, wherein the feature that if the control device fails, the solenoid valve (12) and pressure control valves (6, 7, 8, 9, 10, 11) are de-energized, thereby switching at a previously engaged lower speed to a low gear and at a previously engaged higher speed, to a high gear.