Device for and method of supplying cases into a combustion space of a self-igniting internal combustion engine

A device for controlling the supply of gases including air and recycled exhaust gas components into a combustion space of a self-igniting internal combustion engine, comprising an air intake system, an exhaust gas collection system, an exhaust gas return conduit communicating with the air intake system;

• a control member arranged between the exhaust gas return conduit and the air intake system, the control member being arranged for controlling communication between said return conduit and said air intake system, a first pressure activated setting motor including a control pressure chamber, a reference pressure chamber and a movable wall therebetween, said movable wall being connected to said control member, a first source of pressure and a second source of reference pressure, an electrically activated pressure transformer having input ports connectable respectively to said first and a second pressure sources and an output port providing a control pressure formed from said first and second pressure sources and being connectable by connecting means to said control pressure chamber an electric control circuit for generating a control signal corresponding to operational variables of the engine, particularly to a sucked in quantity of air and to a supplied quantity of fuel, the control signal controlling the actuation of said pressure transformer, said air intake system including an air throttle normally biased into open position to freely pass fresh air into the engine, a second pressure activated setting motor including a control pressure chamber, a reference pressure chamber and a movable wall therebetween, the movable wall of the second setting motor being liked to said air throttle, the control pressure chamber of said second setting motor being connectable by connecting means to the output port of said electrically activated pressure transformer which output port being connectable to said control pressure chamber of said first setting motor, said pressure transformer including a single electrically controlled pressure transforming unit and said connecting means including an electrically controlled directional control valve having a first port connected to the output port of said pressure transforming unit, a second port connected to said reference pressure source, a third port connected to said control pressure chamber of the first setting motor and a fourth port connected to the control pressure chamber of said second setting motor to selectively connect one of said control pressure chambers to said output port of said pressure transforming unit, said electric control circuit being connected to said connecting means and to said electrically controlled pressure transformer to apply pressure into the control chambers of respective setting motors in such a manner that in one operational condition of the engine during which exhaust gas is recycled the control pressure chamber of the second setting motor is supplied with reference pressure from said second pressure source and the control pressure chamber of the first setting motor is supplied via said output port of said pressure transforming unit with control pressure, and in another operational condition of the control pressure chamber of the first setting motor is supplied with reference pressure from the said second pressure source and the control pressure chamber of the second setting motor is supplied via said output port of said pressure transforming unit with control pressure.