Device for controlling an amount of exhaust gas returned to an aspirating line

A device for controlling the amounts of returned exhaust gas of a self-igniting internal combustion engine (1), supplied by a fuel injection pump (15), having an exhaust gas return valve (5) disposed in an exhaust gas return line (4) of the internal combustion engine, said gas return valve is operated by means of a pneumatic servo motor (7) having a work chamber (8) which is controlled by means of a control valve (13) which, in turn, is controlled as a function of a position of a floating lever (16) of the fuel injection pump (15) that controls the injection amount and which, depending on the switching position of the control valve, can be connected with either a control pressure source (12) or a reference pressure source, wherein the floating lever (16) is coupled with a control cam (20) which cooperates with an actuation member (22) of the control valve (13), the control cam describes a continuously increasing or decreasing cam course in relation to the actuation member (22), and the control valve is embodied in such a way that, with increasing actuation of the actuation member (22), the control valve attains three switching positions in sequence when the floating lever (16) moves from an idle position to a full load position, namely a first switching position in accordance with a first switching state, a second switching position in accordance with a second switching state and a third switching position in accordance with a third switching state, wherein the first switching state adjusts the control pressure in the work chamber (8) in such a way that the exhaust gas return valve (5) is closed, and wherein the second switching state sets the control pressure such that the exhaust gas return valve (5) is opened.