Internal combustion engine having dedicated EGR cylinder(s) and improved fuel pump system
AssigneeSouthwest Research Institute
InventorsRaphael Gukelberger, Garrett L. Anderson
Life of this patent
Estimating the term…
Abstract
A method of improving fuel delivery in an engine having one or more cylinders that are over-fueled related to other cylinders, such as a D-EGR engine. The fueling system uses a mechanical fuel pump, which is cam-driven. The cam has lobes corresponding to the desired displacement for each cylinder. The lobe corresponding to the over-fueled cylinder is shaped differently, such that the filling stroke of the pump is increased.
Claims17
A method of providing over-fueling for an internal combustion engine, the engine having a number of cylinders, with a subset of the number of cylinders being one or more over-fueled cylinders, comprising:
- using a mechanical fuel pump to pump fuel to all of the number of cylinders;
- wherein the fuel pump is driven by a camshaft having a lobed cam, such that lobes of the cam result in filling strokes of the fuel pump;
- wherein each lobe corresponds to a filling stroke for one of the number of cylinders;
- wherein each lobe and/or a surface preceding the lobe that corresponds to one of the subset of the number of cylinders is configured to increase fuel delivery to that one of the subset of the number of cylinders by increasing the filling stroke of the fuel pump;
- wherein the same cam controls the amount of fuel delivered to the number of cylinders but results in increased fuel delivered to only the subset of the number of cylinders relative to the remaining of the number of cylinders.
An improved fueling system for an internal combustion engine, the engine having a number of cylinders, with at least one cylinder of the number of cylinders being an over-fueled cylinder, the engine further having a camshaft, comprising:
- an injector provided for each of the number of cylinders cylinder and operable to inject fuel for combustion;
- a mechanical fuel pump operable to pump fuel to all of the number of cylinders via a common rail to the injectors;
- wherein the fuel pump is driven by the camshaft and a lobed cam, such that lobes of the cam result in filling strokes of the fuel pump;
- wherein each lobe corresponds to a filling stroke for one of the number of cylinders;
- wherein the lobe and/or a surface preceding the lobe that corresponds to the over-fueled cylinder is configured to increase fuel delivery to the over-fueled cylinder by increasing the filling stroke of the fuel pump
- wherein the same cam controls the amount of fuel delivered to the number of cylinders but results in increased fuel delivered to only the subset of the number of cylinders relative to the remaining of the number of cylinders.
Dependencies are inferred from the claim text.