Electrohydraulic control device for a drive train of a vehicle

An electrohydraulic control device for a drive train of a vehicle including an engine, a transmission, a source of pressurized fluid, a torque converter connected between the input clutch and the transmission and having a rotating housing, an impeller element connected to the rotating housing through the input clutch, a reactor element, a turbine element connected between the rotating housing and the turbine element, and an input clutch drivingly connected between the engine and the transmission, comprising:

• actuator means including a control member manually movable between first and second positions, wherein the transmission is adapted to responsively shift between a FORWARD and a REVERSE gear ratio in response to movement of said control member from said first position to said second position;
• a lockup clutch connected between the rotating housing and the turbine element of the torque converter;
• means for sensing a rotational output speed of the transmission and responsively producing a transmission output speed signal;
• means for sensing a rotational input speed of the transmission and responsively producing a transmission input speed signal;
• valve means for directing fluid under pressure from the source to the input clutch to controllably engage and disengage the input clutch;
• and
• controlling means for, in response to movement of said control member from said first position to said second position, disengaging the input clutch, receiving said transmission output speed signal and said transmission input speed signal responsively determining a transmission clutch relative speed, and for actuating said valve means to controllably engage the input clutch as a function of the transmission clutch relative speed.