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.

A flow control system for a fuel injector of an internal combustion engine includes: an inlet channel, an outlet channel, a return channel for returning pressurized fuel to a low-pressure system having a lower pressure than the inlet channel, a fuel outlet chamber, a moveable nozzle control member in the fuel outlet chamber for selectively allowing the pressurized fuel to flow into the outlet channel, a biasing member biasing the nozzle control member towards a closed position, a moveable member defining, with the nozzle control member, a fuel control chamber configured to bias the nozzle control member towards its closed position, a moveable valve member for selectively opening and closing a flow passage and a fuel connection between the inlet channel and the fuel control chamber for pressurizing the fuel control chamber.

A fuel injector having a seat plate with a passage throttle; a valve insert arranged at a first side of the seat plate; a valve guide surrounding the valve insert and adapted for slidable reception of the valve insert; a spring sheath surrounding at least a section of a jet needle arranged at a second side of the valve insert, the second side opposite the first side and the seat plate; a valve chamber fluidly connected to the passage throttle; a control chamber adapted for reception of fuel; and a line arranged in the valve insert connecting the control chamber and the valve chamber to one another, wherein the line is closeable by placement of the valve insert onto the spring sheath.

A fuel injection system includes a first high pressure fuel source, a return channel connected to a second low pressure fuel source, a residual pressure regulator having an inlet and an outlet connected to the return channel, and a fuel injector having a control valve arrangement comprising an inlet, an outlet and a return port, a fuel injection nozzle having an outlet chamber, an injection outlet, and a needle member in the outlet chamber. The needle member is biased to a closed position to block fluid communication between the outlet chamber and the injection outlet, and to open fluid communication by a pressure in the outlet chamber. The residual pressure regulator is connected to a spill valve to regulate pressure to a residual pressure higher than the pressure in the return channel and lower than the pressure of the first fuel source.

Device for controlling an injector, including a passage space which can be closed off on one of its two sides by an armature element in order to thereby optionally separate a fluid high-pressure region from a fluid low-pressure region of the injector, a control space for applying a variable pressure to an injector component, preferably an injector needle, a valve which is arranged between another of the two sides of the passage space and the control space, a first connection which connects the high-pressure region of the injector to the passage space, and a second connection which connects the passage space to the control space, wherein the valve is configured to establish a direct connection between the high-pressure region and the control space if the pressure level in the passage space is equal to or higher than a predetermined value.

Methods and systems are provided for a solenoid actuator. In one example, a method may include adjusting a switching frequency during an activation cycle of the solenoid actuator to a lower switching frequency relative to other phases of the activation cycle.

Operating an engine includes injecting a first charge of liquid fuel using a first set of nozzle outlets in a fuel injector, and injecting a second charge of liquid fuel using a second set of nozzle outlets in a fuel injector. The first charge is autoignited in a first engine cycle, and the second charge is autoignited in a second engine cycle, and may be used to pilot ignite a charge of gaseous fuel. Operating the engine further includes limiting errors in targeting of the second charge of liquid fuel caused by transitioning the engine from a first combination to a second combination of speed, load, and boost, by varying an injection pressure of the liquid fuel from the first engine cycle to the second engine cycle.

A configuration is provided for a fuel injector for a common rail fuel system. In one example, the fuel injector may include a housing, an inner chamber enclosed by the housing, and a flow limiting valve. The flow limiting valve may be arranged at a downstream end of the inner chamber and also enclosed by the housing. This configuration may allow the fuel injector housing to have sufficient wall strength to withstand high pressure fuel injection and may allow effective fuel supply cut off when fuel cut off is demanded.

A fuel injector device for injecting fuel into a combustion chamber of an internal combustion engine is provided. Included in the fuel injector is a body having a chamber and a pilot valve assembly including a seat retainer configured to be detachably insertable into the chamber of the body. A pilot valve seat is disposed in the seat retainer and substantially enclosed by the seat retainer. A stator assembly is disposed in the seat retainer and at least partially enclosed by the seat retainer. The pilot valve seat and the stator assembly in the pilot valve assembly are replaceable as a single unit of the pilot valve assembly for the fuel injector.

A method for recognizing an error in a sensor signal during operation of a fuel injector of an internal combustion engine. In the method, a switch valve of the fuel injector is activated with the aid of an activation signal, and the sensor signal is detected as a signal of a sensor, which is provided for the purpose of detecting characteristic operating points of the fuel injector, in a respectively predefined time window of the sensor signal, which includes a point in time of a characteristic operating point of the fuel injector. At least one property of the sensor signal is determined, which includes a signal level and/or a rise time. It is determined, based on the at least one property of the sensor signal, whether an error is present.