US 12,234,782 B1
Dual fuel engine system having fuel-actuated unit pumps and method
Hoisan Kim, Dunlap, IL (US); Dana Ray Coldren, Secor, IL (US); and Lifeng Wang, Dunlap, IL (US)
Assigned to Caterpillar Inc., Peoria, IL (US)
Filed by Caterpillar Inc., Peoria, IL (US)
Filed on Sep. 27, 2023, as Appl. No. 18/373,388.
Int. Cl. F02D 19/06 (2006.01); F02M 43/04 (2006.01)
CPC F02D 19/0694 (2013.01) [F02D 19/0684 (2013.01); F02D 19/0689 (2013.01); F02M 43/04 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A dual fuel engine system comprising:
an engine including a plurality of cylinders formed therein;
a fuel system including at least one fuel injector associated with each respective one of the plurality of cylinders, and each at least one fuel injector having a first fuel outlet set and a second fuel outlet set;
the fuel system further including a pressurized fuel reservoir, a first fuel pump having a first fuel pump outlet fluidly connected to the pressurized fuel reservoir, and a plurality of high pressure first fuel conduits each extending from the pressurized fuel reservoir to one of the first fuel outlet sets;
the fuel system further including a plurality of second fuel pumps each having a pumping element, an actuating fluid inlet for fluidly actuating the pumping element, and a second fuel pump outlet, a plurality of low pressure second fuel conduits each extending to one of the plurality of second fuel pumps, and a plurality of high pressure second fuel conduits each fluidly connecting one of the second fuel pump outlets to at least one of the respective second fuel outlet sets; and
the actuating fluid inlet of each respective one of the plurality of second fuel pumps is fluidly connected to at least one of the first fuel pump outlet or the pressurized fuel reservoir.