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 fuel injector for an engine includes: a solenoid unit including a plurality of solenoids that can be separately controlled; a valve body having a control chamber connected with a supply throttle and a return throttle; and a plurality of armatures disposed between the solenoid unit and the valve body to be able to adjust the amount of fuel that is discharged through the return throttle by being driven by the solenoids of the solenoid unit.

A fuel injection device has a valve body, a drive portion, a nozzle needle, and a control valve body. The valve body defines a control chamber, a valve chamber and a low pressure communication passage. The nozzle needle is displaced due to a fuel pressure variation in the control chamber to open/close an injection port. When the control valve body sits on an upper seat surface, a low pressure communication passage is closed so that the valve chamber is fluidly disconnected from the low pressure chamber. The control valve body defines a gap restriction on the upper seat surface. A flow passage area of a sub orifice provided to the low pressure communication passage is smaller than a flow passage area of the gap restriction.

A distributor apparatus of a common rail system for an internal combustion engine. The distributor apparatus is designed with at least one distributor device having a high-pressure line for fuel and a plurality of feed lines branching off from the high-pressure line within the distributor device. Each feed line leads to an individual accumulator and an injector. The feed line is associated with a restriction device and a discharge bore, which is designed to cooperate with a pressure-measuring device and which is arranged downstream of the restriction device, such that the restriction device is arranged in the feed line and the discharge bore, arranged in the distributor device, is connected to the feed line downstream of the restriction device.

A fuel injector with inlet and discharge ends includes a fuel tube through which fuel is admitted to a fuel passage extending to the discharge end. A valve element reciprocates against and away from a valve seat to prevent or allow fuel discharge. A calibration tube includes first and second ends and defines a portion of the fuel passage through which fuel must pass to the discharge end, the second end defining a spring seat engaging a spring and biasing the spring against the valve element. A fuel filter filters all fuel passing to the discharge end, and provides restriction of a first magnitude. The calibration tube includes a pressure pulsation damping orifice fluidly between the fuel filter and the discharge end through which fuel must pass to the discharge end, the pressure pulsation damping orifice provides restriction of a second magnitude which is greater than the first magnitude.

A fuel injector includes an injector body and a valve stack within the injector body that includes a valve seat plate. The valve seat plate includes a pressure control passage for controlling fuel injection, and a valve seat positioned fluidly between the pressure control passage and a low-pressure drain. The valve seat plate includes a pressure-limiting annular groove that extends circumferentially around the valve seat and axially inward from a side of the valve seat plate where the valve seat is located. The groove enables deformation in response to pressure differences across the valve seat plate in a manner that limits stress concentrations.

A method for monitoring an injector for common-rail injection systems includes detecting an electrical signal indicative of a deformation of a diaphragm of a head plate having a reaction surface facing a control chamber of the injector and processing the deformation signal to determine characteristic data of the operation of the injector.

In some examples, a fuel injector rail assembly may include a fuel rail including a tubular body, with a fuel outlet passage formed through a wall of the tubular body. An injector cup may be connected to the tubular body and may include an injector chamber configured to receive a fuel injector. A first fuel passage formed in the injector cup may include a first diameter, and the first fuel passage may be connected to the fuel outlet passage of the tubular body. Additionally, a second fuel passage may be formed in the injector cup between the first fuel passage and the injector chamber. The second fuel passage may have a second diameter that is smaller than the first diameter of the first fuel passage.

Valve assembly comprising: a valve body with an inlet and an outlet; a valve needle in the valve body preventing fluid flow through the outlet when closed and permitting the flow otherwise; a retaining element connected to the needle, extending radially and remote from the fluid outlet; and an electro-magnetic actuator to actuate the valve needle. The electro-magnetic actuator unit comprises an armature movable relative to the valve body. The armature defines a central axial opening through which the valve needle extends and slides on the valve needle. The retaining element limits the axial displacement of the armature. The armature comprises at least one axial slot arranged adjacent to and connected with the central axial opening, extending through the armature in the axial direction. The retaining element projects beyond the central axial opening and the axial slot projects beyond the retaining element in the radial outward direction.

A control valve arrangement includes a valve body with a filling chamber with a filling hole. A filling valve is arranged in the filling chamber for opening or closing a first fluid communication controlling filling of a first control chamber, the filling valve having a filling valve member with a moving valve seat, the filling valve member being normally biased open by a first spring. A control valve opens and closes a second fluid communication for controlling the emptying of the first control chamber, the control valve being normally biased closed by a second spring. A plug is arranged in the valve body for closing the filling chamber, the plug being provided with an opening which cooperates with the moving valve seat, the opening defining the first fluid communication between the filling chamber and the first control chamber.