In a fuel injection device, a driving unit structure has a magnetic aperture, in which an inner diameter is gradually enlarged toward the mover side, provided in an inner peripheral surface of the magnetic core. It is possible to reduce magnetic delay time upon valve opening from the supply of the electric current to the coil to the rise of magnetic flux and magnetic delay time upon valve closing from the stoppage of the electric current to the coil to reduction of magnetic flux, by providing a magnetic aperture in the inner peripheral surface of the magnetic core. Thus it is possible to improve the dynamic responsiveness upon valve opening and valve closing.

A fuel injection valve includes a valve body, a fixed core, a movable core, a spring and a cup. The movable core has a first core contact surface which contacts the valve body when the movable core is moved by a predetermined distance away from a nozzle hole, and a second core contact surface which contacts the cup when the movable core is moved away from the nozzle hole. The movable core, the cup and the valve body form a fuel storage chamber which is surrounded by the movable core, the cup and the valve body to accumulate fuel. The first core contact surface is located inside the fuel storage chamber. The first core contact surface and the second core contact surface have a communication groove through which the inside and the outside of the fuel storage chamber communicate with each other.

An electromagnetic positioning device includes an armature member for actuating a positioning partner and movable in an armature space relative to a stationary core (30). The armature member conducts magnetic flux upon energization of a stationary coil (32). The coil has a coil support with a winding and at least one external contactable connector (46) embedded at least in sections in the core and/or surrounded by the core. The core has an end surface (34), which is planar at least in sections, for interacting with the armature member. The core and the coil are embedded in and/or surrounded by a one-piece pot-like and/or cup-like housing (38) made of a material suitable for deep-drawing in such a manner that the core rests on a membrane-like, continuous and closed base section of the housing, the base section realizing a boundary surface of the armature space.

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 injection valve includes a valve body, a fixed core, a movable core, a holder, and a stopper. The movable core has an inner core that contacts the stopper, and an outer core press-fitted to an outer peripheral surface of the inner core. The outer core has, in a moving direction of the movable core, a press-fit region which is press-fitted to the outer peripheral surface of the inner core, and a non-press-fit region which is not press-fitted to the outer peripheral surface of the inner core and is adjacent to the press-fit region in the moving direction. Between the inner peripheral surface of the holder and the outer peripheral surface of the movable core, the smallest gap in the press-fit region is larger than the smallest gap in the non-press-fit region.

An electromagnetically-activated actuator includes an electrical coil, an armature moveable between rest and actuated positions, and a bi-directional driver. A method for controlling an actuator event includes applying a supply voltage at a first polarity across the coil for a first duration to drive a forward current through the coil effective to move the armature away from the rest position. The forward current has a forward current peak at the end of the first duration. After the first duration, the supply voltage is applied at a second polarity across the coil for a second duration to drive a reverse current through the coil. The second duration terminates when the reverse current attains a predetermined reverse current peak, wherein the predetermined reverse current peak is coincident with the armature returning to the rest position.

An electromagnetic actuator assembly for a fluid injection valve includes a first coil and a second coil, which are configured for moving an armature, and an electrical connection circuit for connecting the first and second coils to a power supply. The electrical connection circuit is configured to energize the first coil without energizing the second coil in a first operating mode of the actuator assembly and to energize both the first coil and the second coil in a second operating mode of the actuator assembly.

A fuel injection valve includes: a holder which accommodates a valve body, has a surface magnetically facing the outer periphery of an armature, and is joined to a core; a housing which is press-fitted onto the outer periphery of the holder and accommodates a coil; and a cap which covers the fuel upstream side of the coil in a lid shape and is press-fitted onto the outer periphery of the core. The lower surface of the cap is brought into contact with the upper end surface of the housing in a radially slidable state and then an outer peripheral portion of a contact surface between the cap and the housing is joined by laser welding.

A fuel injection valve includes: a movable arrangement that is coupled to a movable core and a needle while a movable flow passage, which forms a part of a flow passage of the fuel injection valve, is formed at an inside of the movable arrangement; and a valve main body that receives the movable arrangement. The movable arrangement has: a first flow-restricting portion that reduces a cross-sectional area of a portion of the movable flow passage; and a second flow-restricting portion that is spaced away from the first flow-restricting portion and reduces a cross-sectional area of another portion of the movable flow passage to a cross-sectional area that is equal to or larger than a cross-sectional area of the first flow-restricting portion. A distance between the first flow-restricting portion and the second flow-restricting portion is larger than an equivalent diameter of the cross-sectional area of the second flow-restricting portion.

In order to provide a solenoid valve (1) with a valve housing (2), in which an electric coil (3) and a magnet armature (5) are arranged, and with a valve element (8) which can be actuated by the magnet armature (5) in an axial actuation direction for opening and closing the solenoid valve (1), wherein a valve lift of the valve element (8) can be limited in a simple manner, it is provided according to the invention that the coil (3) be arranged on a coil carrier (4), wherein an end section (4a), axially facing the magnet armature (5), of the coil carrier (4) is designed as an end stop for the magnet armature (5) in order to limit an axial movement of the magnet armature (5), and that the coil carrier (4) be formed from a plastic, wherein the coil (3) is at least partially integrated into the coil carrier (4).