Control apparatus for internal combustion engines

In an air pressure dependent full-load stop for limiting the movement of a supply quantity adjustment member of a fuel metering apparatus for an internal combustion engine in accordance with induced air-pressure in an intake manifold of the engine, which includes a housing, a movable wall disposed within the housing separating in a pressure-tight manner a first pressure chamber from a counterpart pressure chamber which are defined by the housing and the movable wall, an adjustment member means actuated by the movable wall for limiting the movement of the supply quantity adjustment member, connecting means for connecting the first pressure chamber to the intake manifold of the engine, and a first spring in the pressure chamber and a second spring in the counterpart pressure chamber for exerting a force on the movable wall to determine an initial disposition of the movable wall, wherein the movable wall is displaceable by the induced air pressure of the engine against the force of the second spring, the improvement which comprises:

• an overpressure source means for generating a reference absolute pressure including,
• an air overpressure source of the engine;
• an absolute pressure controller containing an evacuated diaphragm pressure box for maintaining the reference absolute pressure at a predetermined absolute pressure level;
• and
• second connecting means for connecting the overpressure source means to the counterpart pressure chamber which is sealed off from the outside--and wherein the balance of forces between the first and second spring and the pressures in the first pressure chamber and the counterpart pressure chamber determines the position of the adjustment member means and the full load injection quantity.