Method for fuel injection control
AssigneeFord Global Technologies, LLC
InventorsGopichandra Surnilla, Eric Krengel, Joseph Lyle Thomas, Todd Anthony Rumpsa, Michael Howard Shelby
Life of this patent
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Abstract
Methods and systems are described for controlling fuel injection in an engine equipped with a dual injector system including a port injector and a direct injector. A ratio of port injected fuel to direct injected fuel is adjusted based at least on intake valve temperature. The proportion of fuel port injected into a cylinder is increased as the intake valve temperature for the given cylinder increases to improve fuel vaporization in the intake port.
Claims13
A method for an engine, comprising:
- during a hot engine restart, adjusting a ratio of fuel delivered to a cylinder via direct injection relative to a ratio of fuel delivered to the cylinder via port injection based on a temperature of an intake valve of the cylinder and based on a combustion event number since engine start;
- and
- during a cold engine start, adjusting the ratio of fuel delivered to the cylinder via direct injection relative to the ratio of fuel delivered to the cylinder via port injection based on catalyst temperature.
An engine system, comprising:
- an engine including a cylinder;
- a first port injector coupled to the cylinder;
- a second direct injector coupled to the cylinder;
- and
- a control system with computer readable instructions for, generating an initial fuel injection profile for the cylinder based on engine speed and a combustion event number;
- and
- selectively modifying the initial fuel injection profile during a combustion event in the cylinder based on an intake valve temperature of the cylinder, wherein the initial fuel injection profile includes a first proportion of fuel delivered via the second direct injector and a second proportion of fuel delivered via the first port injector, and wherein selectively modifying the initial fuel injection profile during the combustion event in the cylinder includes increasing the second proportion of fuel while correspondingly decreasing the first proportion of fuel as the intake valve temperature of the cylinder increases.
A method for an engine, comprising:
- adjusting a ratio of fuel delivered to a cylinder via direct injection relative to a ratio of fuel delivered to the cylinder via port injection based on a temperature of an intake valve of the cylinder, wherein the ratio of fuel delivered to the cylinder via direct injection relative to the ratio of fuel delivered to the cylinder via port injection is further adjusted based on an alcohol content of the injected fuel, the ratio of fuel delivered to the cylinder via port injection decreased relative to the ratio of fuel delivered to the cylinder via direct injection as the alcohol content of the injected fuel increases, wherein the intake valve is a cam-driven valve closing an opening to a cylinder piston, the intake valve moveably mounted in a cylinder head, the intake valve temperature estimated based on operating conditions including coolant temperature, cylinder head temperature, and oil temperature.
Dependencies are inferred from the claim text.