Limp home capable dual fuel engine and machine using same
AssigneeCaterpillar Inc.
InventorsDana R. Coldren, Joshua W. Steffen, Gregg W. Uhland, Brian K. Garman, Alan R. Stockner
Life of this patent
Estimating the term…
Abstract
A dual fuel engine powers a machine by burning natural gas and liquid diesel fuel. When operating in a low load mode, some of the engine cylinders are fueled with a high ratio of diesel/gas, and the remaining cylinders are unfueled. When operating in a high load mode, all of the engine cylinders are fueled with a low ratio of diesel/gas. When operating in a limp home mode, the fuel injectors are configured to inject only diesel fuel into all of the plurality of engine cylinders.
Claims14
A machine comprising:
- a machine body supported by a conveyance;
- a dual fuel compression ignition engine having a plurality of cylinders, being attached to the machine body and operably coupled to the conveyance;
- a dual fuel system operably coupled to supply the dual fuel compression ignition engine with liquid diesel fuel and natural gas fuel from a single fuel injector directly into respective engine cylinders;
- an electronic controller in control communication with the dual fuel system and having a low load algorithm, a high load algorithm and a limp home algorithm each configured to control operation of the dual fuel system;
- wherein the low load algorithm is configured to inject a high ratio diesel fuel to natural gas fuel into less than all of the plurality of engine cylinders in each engine cycle, and inject no diesel fuel or natural gas fuel into the remaining engine cylinders;
- wherein the high load algorithm is configured to inject a low ratio of diesel fuel to natural gas fuel into all of the plurality of engine cylinders;
- and
- wherein the limp home algorithm is configured to inject only diesel fuel into all of the plurality of engine cylinders.
A method of operating a machine that includes a machine body supported by a conveyance;
- a dual fuel compression ignition engine having a plurality of cylinders, being attached to the machine body and operably coupled to the conveyance;
- a dual fuel system operably coupled to supply the dual fuel compression ignition engine with liquid diesel fuel and natural gas fuel from a single fuel injector directly into respective engine cylinders;
- and an electronic controller in control communication with the dual fuel system and having a low load algorithm, a high load algorithm and a limp home algorithm each configured to control operation of the dual fuel system, the method comprising the steps of:
- idling the machine;
- moving the machine with a load;
- limping the machine home;
- the idling step includes fueling some, but not all, of the cylinders with a high ratio of liquid diesel fuel to natural gas fuel;
- the moving step includes fueling all of the cylinders with a low ratio of liquid diesel fuel to natural gas fuel;
- and
- the limping step includes fueling all of the cylinders exclusively with liquid diesel fuel.
Dependencies are inferred from the claim text.