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US 12,535,041 B2Granted
Systems and methods for at-cylinder fuel switching
AssigneeCaterpillar Inc.
InventorBryan Edward Nelson, Jr.
Life of this patent
Estimating the term…
Abstract
An internal combustion engine system is described herein. The systems described herein allow for switching from the methanol to the diesel as a primary fuel at the cylinder rather than at the system. A valve at an inlet of a primary return tank is used to isolate a primary return tank of a primary fuel. A primary fuel pump is deenergized allowing an input valve to open. Pilot fuel is then directed into both a primary fuel input line and a pilot fuel input line into the injector.
Claims20
A system comprising:
- an internal combustion engine that combusts a primary fuel and a pilot fuel, wherein the engine comprises an injector in a cylinder of the engine, the injector configured to inject the pilot fuel and the primary fuel for combustion;
- a primary fuel pump fluidically connectable to and disconnectable from a primary fuel feed to supply the primary fuel to the injector through a primary fuel input line;
- a pilot fuel pump fluidically connected to a pilot fuel feed to supply the pilot fuel to the injector through a pilot fuel input line;
- a primary return isolation valve for fluidically disconnecting a primary fuel excess line from a primary return tank in a first position of the primary return isolation valve and fluidically connecting the primary fuel excess line in a second position of the primary return isolation valve;
- a primary outlet valve for fluidically connecting the primary fuel to the primary fuel input line when the primary outlet valve is in a first position of the primary outlet valve and fluidically disconnecting the primary fuel from the primary fuel input line when the primary outlet valve is in a second position of the primary outlet valve;
- and
- an input bypass line for providing a portion of the pilot fuel from the pilot fuel pump into the primary fuel input line when the primary outlet valve is in the second position of the primary outlet valve.
4 more elements
An injector system, comprising:
- an injector comprising:
- a pilot fuel inlet for receiving a pilot fuel from a pilot fuel pump through a pilot fuel input line from a pilot fuel pump fluidically connected to a pilot fuel feed;
- a pilot fuel outlet for removing an excess of the pilot fuel into a pilot return tank;
- a primary fuel inlet for receiving a fuel through a primary fuel input line, wherein the fuel comprises:
- a primary fuel from a primary fuel pump when a primary outlet valve fluidically connecting a primary fuel pump to the primary fuel input line is open, and, when an input valve of an input bypass line for providing a portion of the pilot fuel from a pilot fuel pump into the primary fuel input line is closed;
- or
- a pilot fuel from the pilot fuel pump when the primary outlet valve is closed, and, when the input valve is open;
- and
- a primary fuel outlet for removing an excess of the fuel received into the primary fuel input line through a primary fuel excess line.
6 more elements
A method for at-cylinder switching between methanol to diesel as a primary fuel, the method comprising:
- providing a primary fuel from a primary fuel pump into a primary fuel input line through a primary fuel input valve when the primary fuel input valve is in a first position of the primary fuel input valve;
- providing a pilot fuel from a pilot fuel pump into a pilot fuel input line;
- deenergizing the primary fuel pump to stop a flow of the primary fuel into the primary fuel input line;
- positioning the primary fuel input valve in a second position of the primary fuel input valve to direct the flow of the primary fuel to a primary fuel tank;
- and
- positioning a bypass valve in a second position of the bypass valve to direct a portion of the pilot fuel from the pilot fuel pump, into an input bypass line, and then into the primary fuel input line.
3 more elements
Dependencies are inferred from the claim text.