Gaseous fuel engine and sparkless operating strategy therefor
AssigneeCaterpillar Inc.
InventorDavid Yu-Zhang Chang
Life of this patent
Estimating the term…
Abstract
Operating an internal combustion engine system includes advancing a prechamber piston in a fuel delivery igniter to push a main charge of fuel from a prechamber into a cylinder, and advancing the prechamber piston to compression-ignite a pilot charge within the prechamber. Combustion gases of the pilot charge are conveyed into the cylinder to ignite the main charge. Operation of the engine system provides sparkless gaseous fuel ignition.
Claims20
A method of operating an internal combustion engine system comprising:
- advancing a prechamber piston in a fuel delivery igniter to push a main charge of fuel from a prechamber in the fuel delivery igniter into a cylinder in an internal combustion engine;
- advancing the prechamber piston in the fuel delivery igniter to compression-ignite a pilot charge of the fuel within the prechamber;
- conveying combustion gases of the compression-ignited pilot charge of the fuel from the prechamber into the cylinder;
- igniting the main charge of fuel in the cylinder by way of the combustion gases of the compression-ignited pilot charge;
- and
- urging a main piston in the internal combustion engine toward a bottom-dead-center (BDC) position in a power stroke based on combustion of the main charge of fuel ignited by way of the combustion gases of the compression-ignited pilot charge.
A fuel system for a gaseous fuel engine comprising:
- a gaseous fuel conduit;
- a fuel delivery igniter including a housing having formed therein each of a prechamber, a fuel inlet to the prechamber fluidly connected to the gaseous fuel conduit, and a nozzle outlet from the prechamber, and further including a prechamber piston movable in the prechamber between a retracted position and an advanced position;
- a fueling and ignition control system including an electronically controlled actuator structured to advance the prechamber piston through the prechamber, and an electronic control unit coupled with the electronically controlled actuator;
- the electronic control unit is structured to:
- monitor an engine timing of a gaseous fuel engine in an engine cycle;
- command advancing the prechamber piston, using the electronically controlled actuator, according to an earlier engine timing in the engine cycle such that the prechamber piston pushes a main charge of gaseous fuel from the prechamber through the nozzle outlet;
- and
- command advancing the prechamber piston, using the electronically controlled actuator, according to a later engine timing in the engine cycle such that the prechamber piston compression-ignites a pilot charge of the gaseous fuel within the prechamber.
A method for sparkless operation of a gaseous fuel internal combustion engine system comprising:
- feeding a gaseous fuel from a gaseous fuel supply into a prechamber in a fuel delivery igniter;
- pushing unignited gaseous fuel from the prechamber into a cylinder in a gaseous fuel engine using a prechamber piston during an intake stroke of a main piston in the cylinder;
- mixing the unignited gaseous fuel with air in the cylinder;
- compression-igniting gaseous fuel in the prechamber using the prechamber piston;
- conveying combustion gases of the compression-ignited gaseous fuel into the mixture of unignited gaseous fuel and air;
- and
- igniting the mixture of unignited gaseous fuel and air by way of the combustion gases of the compression-ignited gaseous fuel.
Dependencies are inferred from the claim text.