Electromagnetic solenoid has movable core having end surface that is formed between inner circumferential surface and outer circumferential surface of movable core; and fixed core having end surface that is formed between inner circumferential surface and outer circumferential surface of fixed core and faces the end surface of movable core. Ring-shaped protruding portion is formed at least either one of the end surface of the movable core or the end surface of the fixed core. Protruding portion is provided at a position that is shifted to a radially inner circumferential side of the end surface. A length between apex and inner circumferential edge of protruding portion is shorter than a length between the apex and an outer circumferential edge of protruding portion.

An object of the present invention is to provide a fuel injection valve that realizes atomization while suppressing spread of a spray. A fuel injection valve includes: a valve body and a valve seat that cooperate to open and close a fuel passage; a swirl imparting chamber that is arranged on a downstream side of an opening and closing portion of the fuel passage by the valve body and the valve seat, and imparts a swirling velocity to fuel; a communication passage arranged on an upstream side of the swirl imparting chamber and connected to the swirl imparting chamber; and fuel injection holes and that are open at a bottom surface of the swirl imparting chamber and injects fuel imparted with the swirling velocity in a swirl passage to an outside, the fuel injection holes and configured such that cross-sectional areas of the fuel injection holes and increase from the inlet to the outlet.

A valve includes an electromagnetic actuator, which has an armature in an armature space and guided on a valve needle operable by the actuator using the armature. A first and a second stop element that interact with a first and second end face, respectively, of the armature are situated on the valve needle. The armature has a spring receptacle, which is open towards the first end face of the armature, and into which a spring is inserted. The armature has at least one fluid channel, which, during operation, allows fluid to pass through between first and second regions of the armature space at the first and second end faces, respectively, of the armature. The fluid channel incorporates at least part of the spring receptacle. Sections of the fluid channel run radially outwards along a direction oriented from the first to the second end face and coaxial to a longitudinal axis.

A drive unit of a fuel injection device includes a driver circuit. The driver circuit opens and closes a valve element of the fuel injection device by supplying a drive current to the fuel injection device. The driver circuit supplies the drive current to open the valve element and sets the drive current to zero in an intermediate lift area. The intermediate lift area is an area is which a lift amount of the valve element is smaller than a maximum target lift amount.

Methods and systems are provided for a fuel injector for an engine. In one example, the injector may be adapted with a plurality of nozzles configured to enhance atomization of fuel. The plurality of nozzles may have geometries that increase turbulence and rotation of fuel flow therethrough. In some examples, the injector may also include a multi-stage counterbore that reduces a likelihood of coking at the injector.

Method to determine an opening time of an electromagnetic fuel injector; the electromagnetic fuel injector is controlled using a series of progressively increasing energization times of the electromagnetic actuator; for each control of the electromagnetic injector, the presence or the absence of a closing of the injection valve is detected; the opening time is identified, which is equal to an intermediate value between the last energization time of the electromagnetic actuator for which the absence of a closing of the injection valve was determined and the first energization time of the electromagnetic actuator for which the presence of a closing of the injection valve was determined.

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.

The invention relates to a fuel injector for injecting two liquid and/or gaseous fuels with an injector housing (1), comprising a nozzle body (2) and a valve body (3). A first nozzle needle (7), arranged such that it can move in a stroke-like manner, is arranged in said injector housing (1) for opening and closing an injection cross-section (27). The first nozzle needle (7) is thereby designed as a hollow needle in which a second nozzle needle (8), arranged such that it can move in a stroke-like manner, is arranged. Same cooperates with an inner nozzle seat (25) formed in the first nozzle needle (7) to open and close at least one injection opening (35). The first nozzle needle (7) and the second nozzle needle (8) border an injection chamber (20) that can be filled with fuel via a supply throttle (36). In addition, in an upper switch position, the second nozzle needle (8) is in contact with a seal seat (38) and thereby separates a connection between the injection chamber (20) and the supply throttle (36).

An anti-reflection device for preventing the reflection of pressure waves inside a fuel injection valve. The anti-reflection device includes an essentially cylindrical base body with a first base side, a second base side, and an outer surface. The anti-reflection device also includes a longitudinal axis orientated parallel to a propagation direction of a pressure wave. The longitudinal axis penetrating the first base side and the second base side. The anti-reflection device also includes a flow path for fuel formed between the first base side and the second base side. The flow path forming a curve around the longitudinal axis.

For a fuel injection device, a configuration to improve fuel sealability when a valve is closed is provided. Therefore, the fuel injection device includes: a valve body that opens and closes a fuel flow path; a movable iron core in which a fuel passage hole communicating an upstream side and a downstream side is formed, and that operates the valve body toward the upstream side; a biasing spring whose one end contacts the movable iron core, and that biases the movable iron core in a valve opening direction; and a regulating unit that regulates movement of the one end of the biasing spring, in which the shortest distance between the one end of the biasing spring and the fuel passage hole is larger than a radial travel distance of the one end until radial movement of the one end is regulated by the regulating unit.