A fuel injector assembly in one embodiment includes a nozzle, at least one needle, and at least one actuator. The nozzle includes at least one cavity in fluid communication with nozzle openings. The at least one needle is movably disposed within the at least one cavity, and prevents flow through the nozzle openings in a closed position. The at least one actuator is configured to move the at least one needle within the cavity. The at least one actuator is configured to move the at least one needle to at least a first fuel delivery configuration and a second fuel delivery configuration. A first amount of fuel is delivered through the nozzle openings with the at least one needle in the first fuel delivery configuration, and a second amount of fuel is delivered through the nozzle openings with the at least one needle in the second fuel delivery configuration.

A fuel injector assembly in one embodiment includes a nozzle, at least one needle, and at least one actuator. The nozzle includes at least one cavity in fluid communication with nozzle openings. The at least one needle is movably disposed within the at least one cavity, and prevents flow through the nozzle openings in a closed position. The at least one actuator is configured to move the at least one needle within the cavity. The at least one actuator is configured to move the at least one needle to at least a first fuel delivery configuration and a second fuel delivery configuration. A first amount of fuel is delivered through the nozzle openings with the at least one needle in the first fuel delivery configuration, and a second amount of fuel is delivered through the nozzle openings with the at least one needle in the second fuel delivery configuration.

Provided is a fuel injection device that can secure strength capable of withstanding high fuel pressure. In a fuel injection device in which a fuel boundary includes two or more components, two components are press-fitted with an inner diameter and an outer diameter and are brought into contact at a butting surface, abutting welding is performed from a direction nearly parallel to the butting surface, an inner diameter side corner portion of the butting surface of a component to be fitted and press-fitted on an inner diameter side is chamfered longer in a direction perpendicular to the butting surface to increase a welding coupling length than a butting length, welding coupling length is less than welding depth, weld penetration depth is not less than material thickness, and the center of the weld is on a base material side, the outer diameter of which is larger than a joining face.

An inner side wall surface of a gap forming member, which is opposed to a flange outer wall surface of a flange of a needle, is slidable relative to the flange outer wall surface. Also, an outer side wall surface of the gap forming member, which is opposed to a stationary core inner wall surface of a stationary core, is slidable relative to the stationary core inner wall surface. The flange outer wall surface and the outer side wall surface are curved to project in a radially outer direction of a housing in a cross section thereof taken along an imaginary plane, which includes an axis of the housing.

A fuel injection device is provided with a valve body, a nozzle needle, a movable plate, and a support spring. The valve body has a control chamber therein. The control chamber is defined by a defining wall which has a dividing wall portion. The dividing wall portion divides the control chamber into an accommodation chamber and a backpressure chamber. The accommodation chamber accommodates a movable plate and a support spring. A fuel pressure in the backpressure chamber is applied to the nozzle needle. The dividing wall portion has a restriction hole fluidly connecting the accommodation chamber and the backpressure chamber with each other, and a support surface supporting the support spring.

A method is provided for pairing at least two injectors, e.g., two fuel injectors for a direct injection system of an internal combustion engine, wherein a criterion for the pairing of the at least two injectors is a total leakage and/or a pressure difference at a transfer pin of the respective injector. A method for producing an injector, e.g., a fuel injector for a direct injection system of an internal combustion engine, is also provided, wherein at least two instances of mechanical backlash, e.g., instances of pairing backlash, that are relevant to injection amounts, leakage amounts, and/or pressure differences of the injector are paired with each other.

A fluid injector is shown and described, including an injector housing and an armature which is coupled to a valve needle. A first bellow surrounds a first space. A first axial end of the first bellow is connected to the injector housing and a second axial end of the first bellow is connected to a first axial side of the armature. A second bellow surrounds a second space. A first axial end of the second bellow is connected to a second axial side of the armature and a second axial end of the second bellow is connected to the housing.

The present disclosure teaches a method for operating an injector with piezoelectric direct drive of an injection system of an internal combustion engine. The method may comprise providing a current to the piezoelectric actuator at a first level, then quickly reducing the current for charging the piezoelectric actuator before or after the opening of the nozzle needle and before the mechanical impacting of the needle or the hydraulic equilibrium point of the needle, the current reduced to such an extent that the sum of the forces acting on the nozzle needle become approximately zero in the case of a small needle lift (part lift), and after reducing the current, supplying a low current in a constant or ramp-shaped fashion until a predetermined setpoint energy is reached.

A fuel injector assembly in one embodiment includes a nozzle, at least one needle, and at least one actuator. The nozzle includes at least one cavity in fluid communication with nozzle openings. The at least one needle is movably disposed within the at least one cavity, and prevents flow through the nozzle openings in a closed position. The at least one actuator is configured to move the at least one needle within the cavity. The at least one actuator is configured to move the at least one needle to at least a first fuel delivery configuration and a second fuel delivery configuration. A first amount of fuel is delivered through the nozzle openings with the at least one needle in the first fuel delivery configuration, and a second amount of fuel is delivered through the nozzle openings with the at least one needle in the second fuel delivery configuration.

A fuel injection system is provided. The system includes a completely sealed housing surrounding the key components of the fuel injection system.