Altitude dependent fuel injection timing
AssigneeGeneral Motors Corporation
InventorsRobert P. Black, Stephen W. Smerika
Life of this patent
Estimating the term…
Abstract
The engine operating angle at which a determined fuel injection quantity is delivered to the engine is varied in accord with barometric pressure variations to compensate an engine air-fuel mixing time to offset variations in air-fuel mixture homogeneity prior to combustion, promoting complete combustion, increased engine performance, increased catalytic converter efficiency and durability over a wide range of barometric pressure values.
Claims9
A fuel injection timing control method for injecting a quantity of fuel into an automotive engine, comprising the steps of:
- generating a pressure value representing barometric pressure;
- referencing a base value indicating an engine operating angle at which the quantity of fuel is to be delivered to the engine;
- referencing an adjustment value as a predetermined function of the generated pressure value;
- adjusting the referenced base value in accord with the referenced adjustment value;
- and
- injecting the quantity of fuel substantially at the angle corresponding to the adjusted referenced base value.
A method for determining an engine operating angle at which to deliver a predetermined fuel quantity to the engine, comprising the steps of:
- establishing a base fuel injection timing value;
- estimating barometric pressure;
- referencing a fuel injection timing offset value as a predetermined function of barometric pressure;
- adjusting the base fuel injection timing value by the referenced fuel injection timing offset value;
- and
- delivering the predetermined fuel quantity to the engine at the engine operating angle corresponding to the adjusted base fuel injection timing value.
Dependencies are inferred from the claim text.