System & method for controlling camshaft timing, air/fuel ratio, and throttle position in an automotive internal combustion engine
AssigneeFord Global Technologies, LLC
InventorsAnna Stefanopoulou, Mrdjan J Jankovic
Life of this patent
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Abstract
A system for controlling camshaft timing, air/fuel ratio and electronic throttle position in an automotive internal combustion engine uses a controller for operating a camshaft phaser, electronic throttle positioner and fuel injectors. The controller determines camshaft timing, steady-state electronic throttle position, steady-state fuel supply, and compensatory transient electronic throttle position, and transient fuel supply such that an engine operating with the present system has the torque output characteristics matching a conventional engine having fixed camshaft timing, but with lower fuel consumption and lower exhaust emissions than a conventional engine.
Claims7
A method for controlling the camshaft timing, air/fuel ratio, and electronic throttle position in an automotive internal combustion engine, comprising:
- determining a camshaft timing advance value for a camshaft which operates cylinder intake and exhaust valves of the engine;
- determining a steady-state position for an electronic air throttle;
- determining a steady-state air/fuel ratio rate;
- determining transient values for electronic air throttle position and air/fuel ratio;
- and
- determining a rich air/fuel ratio suitable for purging a lean NOx trap based upon a quantity of fuel suitable for operating the engine at approximately a stoichiometric air/fuel ratio, but with insufficient air, so as to cause enrichment of the air and fuel mixture.
Dependencies are inferred from the claim text.