A dual fuel system for an internal combustion engine includes a first fuel supply of a liquid pilot fuel, a primary fuel supply of a liquid primary fuel, and a dual fuel injector. The dual fuel injector includes a spill valve fluidly connected with a plunger cavity and movable to control a start of injection and an end of injection, and an admission valve. The admission valve is movable to admit a pilot fuel into the fuel injector, such that the pilot fuel is conveyed through an outlet check to form, within a primary fuel passage fluidly connected to the plunger cavity, a segmented fuel charge of leading pilot fuel and trailing primary fuel by displacing some of the primary fuel. The liquid pilot fuel may be a higher cetane/lower octane liquid fuel, and the primary fuel may be a lower cetane/higher octane liquid fuel.

Methods and systems are provided for a ducted fuel injector. In one example, the ducted fuel injector comprises a plurality of passages, with at least one of the passages configured to receive an oxygen poor gas from a reservoir or an adjacent cylinder to decrease a likelihood of pre-ignition in the duct.

A fuel injection valve includes a nozzle portion for injecting fuel, a fuel inlet port, a fuel supply main passage for supplying the fuel from the fuel inlet port to the nozzle portion, a pressure sensor for detecting fuel pressure in the fuel supply main passage, and a fuel introduce passage for supplying the fuel from the fuel supply main passage to the pressure sensor. The fuel supply main passage includes a first fuel supply passage extending in a first direction from the fuel inlet port to the pressure sensor and a second fuel supply passage extending in a second direction from the pressure sensor to the nozzle portion.

A dual fuel system for an internal combustion engine includes a first fuel supply of a liquid pilot fuel, a primary fuel supply of a liquid primary fuel, and a dual fuel injector. The dual fuel injector includes a spill valve fluidly connected with a plunger cavity and movable to control a start of injection and an end of injection, and an admission valve. The admission valve is movable to admit a pilot fuel into the fuel injector, such that the pilot fuel is conveyed through an outlet check to form, within a primary fuel passage fluidly connected to the plunger cavity, a segmented fuel charge of leading pilot fuel and trailing primary fuel by displacing some of the primary fuel. The liquid pilot fuel may be a higher cetane/lower octane liquid fuel, and the primary fuel may be a lower cetane/higher octane liquid fuel.

A dual fuel system for an internal combustion engine includes a first fuel supply of a liquid pilot fuel, a primary fuel supply of a liquid primary fuel, and a dual fuel injector. The dual fuel injector includes a spill valve fluidly connected with a plunger cavity and movable to control a start of injection and an end of injection, and an admission valve. The admission valve is movable to admit a pilot fuel into the fuel injector, such that the pilot fuel is conveyed through an outlet check to form, within a primary fuel passage fluidly connected to the plunger cavity, a segmented fuel charge of leading pilot fuel and trailing primary fuel by displacing some of the primary fuel. The liquid pilot fuel may be a higher cetane/lower octane liquid fuel, and the primary fuel may be a lower cetane/higher octane liquid fuel.

A dual fuel system for an internal combustion engine includes a first fuel supply of a liquid pilot fuel, a primary fuel supply of a liquid primary fuel, and a dual fuel injector. The dual fuel injector includes a spill valve fluidly connected with a plunger cavity and movable to control a start of injection and an end of injection, and an admission valve. The admission valve is movable to admit a pilot fuel into the fuel injector, such that the pilot fuel is conveyed through an outlet check to form, within a primary fuel passage fluidly connected to the plunger cavity, a segmented fuel charge of leading pilot fuel and trailing primary fuel by displacing some of the primary fuel. The liquid pilot fuel may be a higher cetane/lower octane liquid fuel, and the primary fuel may be a lower cetane/higher octane liquid fuel.

Methods and systems are provided for a fuel injector. In one example, a system comprises an injector spool valve having a fuel outlet shaped to flow fuel to different portions of a nozzle inlet based on an actuation of the injector spool valve, thereby adjusting a fuel injection angle of a fuel injection.

A fuel injector includes an injector housing, an outlet check, an injection control valve assembly, and a valve seat orifice plate integrating a valve seat and various orifices for outlet check control. In the valve seat orifice plate a drain orifice extends between a valve seat surface and a check control chamber formed between a closing hydraulic surface of the outlet check and the valve seat orifice plate. First and second re-pressurization orifices extend between an outer surface of the valve seat orifice plate and the check control chamber.

Methods and systems are provided for a ducted fuel injector. In one example, the ducted fuel injector comprises a plurality of passages, with at least one of the passages configured to receive an oxygen poor gas from a reservoir or an adjacent cylinder to decrease a likelihood of pre-ignition in the duct.

A valve for metering fluids, for fuel injection valves for internal combustion engines, includes an electromagnetic actuator in a housing and a valve needle actuatable by an armature of the actuator, which actuates a valve closing body interacting with a valve-seat surface to form a sealing seat. The armature is movably guided on the valve needle. A stop element connected to the valve needle limits, with an actuation of the valve needle, a relative motion between the armature and the valve needle. The stop element includes at least one elastically deformable part and one stop piece, the elastically deformable part being shaped as a sleeve, and the stop element being configured so that the armature, upon the limitation of the relative motion between the armature and the valve needle, initially contacts the elastically deformable part and impacts the stop piece after a corresponding elastic deformation of the elastically deformable part.