Abstract: 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.

Abstract: 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.

Abstract: Various embodiments include an anti-reflection device for preventing the reflection of pressure waves inside an injection valve comprising: a cylindrical base body with a longitudinal axis L to be orientated parallel to a propagation direction of a pressure wave; a first section adjacent to a first base side having a cavity shaped as a hollow cone, a longitudinal axis of the cone orientated parallel to the longitudinal axis L of the device, and a base area of the cone coplanar with the first base side of the cylindrical base body; and a second section adjacent to the second base side comprising a through-hole in fluid communication with the cone, hydraulically linking the second base side with the first base side. The through-hole makes an angle ? with the longitudinal axis L, wherein 40°???60°.

Abstract: The teachings of the present disclosure describe an injector having an injector housing, an actuator, and a nozzle needle, wherein the actuator is arranged in an actuator space of the injector housing. The injector may include a control piston bore in the injector housing, in which a control piston is arranged, a leakage pin bore between the actuator space and the control piston bore, and a leakage pin coupling the control piston to the actuator, the leakage pin arranged in the leakage pin bore. The control piston may be hydraulically connected to the nozzle needle in order to open or close an outlet opening of the injector housing. The injector may include a high pressure line configured to convey a fuel under pressure to the nozzle needle and a feedline in the injector housing connecting the leakage pin bore to the high pressure line.

Abstract: A piezo injector includes an actuator space in which a piezo actuator is arranged, a control piston bore in which a control piston with an end face is arranged, a leakage pin arranged between the piezo actuator and the end face to couple the piezo actuator with the control piston, and a union for fluidic communication with the control piston bore which union has a hydraulic throttle.

Abstract: Various embodiments include an anti-reflection device for preventing the reflection of pressure waves inside an injection valve comprising: a cylindrical base body with a longitudinal axis L to be orientated parallel to a propagation direction of a pressure wave; a first section adjacent to a first base side having a cavity shaped as a hollow cone, a longitudinal axis of the cone orientated parallel to the longitudinal axis L of the device, and a base area of the cone coplanar with the first base side of the cylindrical base body; and a second section adjacent to the second base side comprising a through-hole in fluid communication with the cone, hydraulically linking the second base side with the first base side. The through-hole makes an angle ? with the longitudinal axis L, wherein 40°???60°.

Abstract: The present disclosure relates to internal combustion engines. The teachings thereof may be embodied in injection valves with servo-valve control for injecting fuel into the combustion chamber. For example, an injection valve may include a valve pin connected to a valve body and an actuator preloaded by an actuator spring. The valve pin is fitted with a very small clearance to form a sealing gap between the valve pin and the valve body which includes bores. The lower end of the valve pin forms a coupling volume between the valve pin and the valve body, connected via the sealing gap and the bores to the valve chamber. The sealing gap provides a fluidic connection between the coupling volume and the valve chamber, but, during the short time of valve actuation, practically no exchange of fluid can take place between coupling volume and valve chamber so that the coupling volume does not substantially change in said short time.

Abstract: 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.

Abstract: An injector includes an actuator arranged in an actuator space, a piston guide having a bore hole, and a piston arranged in the bore hole. The piston has a first end face facing the actuator and delimiting a first space in and/or on the bore hole, and a second end face lying opposite the first space and delimiting an adjoining second space in and/or on the bore hole. The piston is arranged between the first and second spaces, and a gap extends around the circumference of the piston between the piston and the bore hole. The piston includes a first material and the piston guide includes a second material, the first and second materials having different thermal expansion properties such that when the piston guide and/or piston are heated, the gap width of the gap decreases to limit fuel leakage between the first space and second spaces.

Abstract: A piezo injector includes a piezo actuator arranged in an actuator chamber and a valve plunger arranged in a valve plunger bore and having a first end face facing the piezo actuator. The valve plunger is arranged between a first control chamber defined by a valve plunger bore portion delimited by the first end face and a spring chamber formed by a valve plunger bore portion opposite the first control chamber. A second control chamber is delimited by a second face of a nozzle needle and a sleeve guided by the nozzle needle. A leakage pin is arranged in a leakage pin bore between the piezo actuator and the first end face of the valve plunger. The leakage pin bore is formed in an intermediate plate arranged on a side of a control plate facing the piezo actuator, the valve plunger bore being formed in said control plate.

Abstract: A piezo injector for direct fuel injection may comprise an injector body, an actuator unit having a piezoelectric actuator with a head plate and a base plate, a hydraulic coupler having a coupler piston, a coupler cylinder, and a coupler spring, and a nozzle unit having a nozzle needle arranged in a nozzle body. The piezoelectric actuator is surrounded by a corrugated tube braced between the head plate and the base plate such that the piezoelectric actuator has a preload imparted to it. The coupler spring forces the coupler piston against a face side, facing toward the coupler piston, of the nozzle needle.

Abstract: A solid actuator has an actuator structural unit, a top plate and a base plate. A hollow cylinder part made of maraging steel is heated to a predetermined first temperature at which the maraging steel is in an austenitic state. A corrugated tube is shaped from the hollow cylinder part by a shaping process, while the maraging steel is still in an austenitic state. The corrugated tube is cooled such that the maraging steel is in a martensitic state. The actuator structural unit is inserted into the corrugated tube. The top plate and the base plate are fixed to the corrugated tube such that the actuator structural unit is clamped between the top plate and the base plate at a predetermined pre-tension.

Abstract: A fluid injector has a solid state actuator and a control piston unit arranged in a recess of an injector body. A transmission pin mechanically couples the actuator to the control piston unit. A first control chamber, coupled hydraulically to a second control chamber, is delimited by the control piston unit and the injector body. A control piston of the control piston unit has an end surface that is coupled to the transmission pin and which delimits the first control chamber. The control piston unit has a control sleeve arranged coaxially with the control piston and an inwardly directed projection that provides a driving coupling between the control piston and the control sleeve after a predefined control stroke of the control piston. The driving coupling results in the control piston influencing a free volume of the first control chamber during an axial movement of the control piston.

Abstract: The present disclosure relates to internal combustion engines. The teachings thereof may be embodied in injection valves with servo-valve control for injecting fuel into the combustion chamber. For example, an injection valve may include a valve pin connected to a valve body and an actuator preloaded by an actuator spring. The valve pin is fitted with a very small clearance to form a sealing gap between the valve pin and the valve body which includes bores. The lower end of the valve pin forms a coupling volume between the valve pin and the valve body, connected via the sealing gap and the bores to the valve chamber. The sealing gap provides a fluidic connection between the coupling volume and the valve chamber, but, during the short time of valve actuation, practically no exchange of fluid can take place between coupling volume and valve chamber so that the coupling volume does not substantially change in said short time.

Abstract: A piezo injector with an actuator chamber, in which a piezo actuator is arranged, includes an upper section (the injector body) and a lower section (the nozzle body). The piezo injector also has a control piston bore formed in the nozzle body, wherein a control sleeve, in which a control piston is received, is arranged in the control piston bore. The control sleeve seals against an intermediate plate with a first front face facing the piezo actuator. The control piston has a first side facing the piezo actuator, wherein the first front face of the control piston and the section of the control sleeve facing the piezo actuator form a first control chamber.

Abstract: The teachings of the present disclosure describe an injector having an injector housing, an actuator, and a nozzle needle, wherein the actuator is arranged in an actuator space of the injector housing. The injector may include a control piston bore in the injector housing, in which a control piston is arranged, a leakage pin bore between the actuator space and the control piston bore, and a leakage pin coupling the control piston to the actuator, the leakage pin arranged in the leakage pin bore. The control piston may be hydraulically connected to the nozzle needle in order to open or close an outlet opening of the injector housing. The injector may include a high pressure line configured to convey a fuel under pressure to the nozzle needle and a feedline in the injector housing connecting the leakage pin bore to the high pressure line.

Abstract: A piezo actuator for a fuel injector, including: a piezo layer stack having a longitudinal extension; and an insulation layer surrounding the piezo layer stack. The insulation layer has an insulation layer outer surface, facing away from the piezo layer stack, which defines an outer diameter of the insulation layer. In addition, a preloading device for preloading the piezo layer stack is also provided along the longitudinal extension, wherein the preloading device has a preloading device inner surface, facing towards the piezo layer stack, which defines an inner diameter of the preloading device. In a non-assembled state, the outer diameter of the insulation layer is greater that the inner diameter of the preloading device, such that, in an assembled state, the insulation layer is compressed in the preloading device. The invention also relates to a fuel injector having said piezo actuator.

Abstract: A piezo injector for direct fuel injection may comprise an injector body, an actuator unit having a piezoelectric actuator with a head plate and a base plate, a hydraulic coupler having a coupler piston, a coupler cylinder, and a coupler spring, and a nozzle unit having a nozzle needle arranged in a nozzle body. The piezoelectric actuator is surrounded by a corrugated tube braced between the head plate and the base plate such that the piezoelectric actuator has a preload imparted to it. The coupler spring forces the coupler piston against a face side, facing toward the coupler piston, of the nozzle needle.

Abstract: The present disclosure relates to a fuel injector comprising a piston and a fluid line. The geometry of the piston and/or a geometry of the fluid line are/is configured such that the piston is positioned eccentrically in the fluid line by the fluid.

Abstract: An injector includes an actuator arranged in an actuator space, a piston guide having a bore hole, and a piston arranged in the bore hole. The piston has a first end face facing the actuator and delimiting a first space in and/or on the bore hole, and a second end face lying opposite the first space and delimiting an adjoining second space in and/or on the bore hole. The piston is arranged between the first and second spaces, and a gap extends around the circumference of the piston between the piston and the bore hole. The piston includes a first material and the piston guide includes a second material, the first and second materials having different thermal expansion properties such that when the piston guide and/or piston are heated, the gap width of the gap decreases to limit fuel leakage between the first space and second spaces.