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.

Various embodiments may include a method for adapting the opening behavior of a fuel injector having a solenoid drive, the method comprising: applying a voltage pulse having a predetermined electrical voltage to the solenoid drive; acquiring a time profile of the strength of a current flowing through the solenoid drive; comparing the acquired time profile with a reference profile; and adjusting a value of a mechanical parameter of the fuel injector to reduce a deviation between the acquired time profile of the strength of the current and the reference profile.

A method is disclosed for controlling an injector of a combustion engine. The injector includes an injection valve housing with an injection valve cavity, a valve needle axially movable within the injection valve cavity, a valve seat on which the valve needle rests in a closed position and from which the valve needle is lifted for an open position, and a spring element configured and arranged to exert a preload force on the valve needle acting to urge the valve needle in the closed position. A calibration value is provided, which is representative for the preload force. A base quantity is provided correlated to the fluid volume to be dispensed by the injector. A set-point opening time length is determined based on the calibration value and the base quantity. The valve needle of the injector is controlled to be in the opening position correlated to the set-point opening time length.

An insert for use with a fuel injector comprises a shaft including a substantially cylindrical configuration defining a shaft cylindrical axis, a shaft radial direction, and a shaft diameter; and a head including a substantially cylindrical configuration defining a head cylindrical axis, a head radial direction, and a head diameter. The shaft and head may be attached to each other, the shaft cylindrical axis and the head cylindrical axis may be parallel to each other, the head diameter may be greater than the shaft diameter, and the shaft cylindrical axis may be spaced away from the head cylindrical axis.

The present disclosure relates to internal combustion engines. Various embodiments thereof may include a fuel injection valve for a combustion engine comprising: a valve body with a cavity; a valve needle movable in the cavity; an actuator assembly to actuate the valve needle. The actuator assembly includes an electro-magnetic coil, a pole piece positioned inside the cavity, and an armature element. The armature element moves within the cavity to move the valve needle in a predetermined direction. A fixing ring abutting the pole piece, fixed to the valve body by means of joining to a circumferential surface of the cavity.

An insert for use with a fuel injector comprises a shaft including a substantially cylindrical configuration defining a shaft cylindrical axis, a shaft radial direction, and a shaft diameter; and a head including a substantially cylindrical configuration defining a head cylindrical axis, a head radial direction, and a head diameter. The shaft and head may be attached to each other, the shaft cylindrical axis and the head cylindrical axis may be parallel to each other, the head diameter may be greater than the shaft diameter, and the shaft cylindrical axis may be spaced away from the head cylindrical axis.

A control valve assembly of a fuel injector includes a first valve arrangement wherein a first valve spool is guided in a first hydraulic bore provided in a body of the assembly. The control assembly further includes a first tubular sleeve having a seating portion which end face defines the first seating face, the first sleeve being fixed in the first hydraulic bore and the first spool extending through the sleeve.

In general, the subject matter described in this disclosure can be embodied in a fuel injector that includes an upper housing portion that defines an inlet passage adapted to receive fuel, and a lower housing portion that is attached to the upper housing portion and that defines an injector outlet adapted to dispense fuel. The fuel injector includes an electromagnetic coil assembly that is user removable while the upper housing portion remains attached to the lower housing portion. The fuel injector includes a movable pintle that is biased to a closed position that is adapted to prevent fuel from flowing through the injector outlet, and movable, responsive to magnetic force produced by energizing the electromagnetic coil assembly, to an open position that is adapted to permit fuel to flow through the injector outlet.

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 valve assembly is provided with a valve body, a valve needle and an armature. An actuator assembly surrounds the valve assembly. The actuator assembly includes a housing and a coil. The coil can be energized so as to induce a force for axially displacing the armature. A flow characteristic of fluid to be injected by the injector is adjusted by axially shifting the valve assembly and the actuator assembly relative to one another.