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.

An injector which incorporates the use of an insert to compensate for the change in volume of diesel exhaust fluid as the diesel exhaust fluid freezes, reducing or eliminating the effects on the calibration of the injector. The calibration freeze protection insert is located adjacent a calibration sleeve in the injector, where the insert is welded to an inlet tube. Any axial forces applied to the calibration sleeve from the blocking force of the freezing diesel exhaust fluid are transmitted to the insert, and the position of the insert is maintained by the welds. The insert and the calibration sleeve are configured to only allow small amounts of diesel exhaust fluid to migrate around the injector components, which is able to be compensated for by the elastic modulus of the various injector components.

A cup is in a bottomed tubular shape to receive an injector along an injector axis. A bracket is extended from a sidewall of the cup. The bracket includes at least one arm and a body. The at least one arm connects the body with the cup. The body forms a screw opening configured to receive a screw along a screw axis. The body has a pivot end on an opposite side of the screw axis from the injector axis.

A fluid injector for injecting fuel into a combustion engine includes a valve, a tubular valve body and an orifice disc, wherein the valve comprises valve seat and a movable opening device in order to open and close the valve, wherein the orifice disc is arranged at the valve seat on the opposite side of the opening device and is configured to shape a spray of the fluid dispensed by the fluid injector in an open position of the valve. A compensation element and a fastening element are provided, wherein the compensation element is arranged between the valve seat and the fastening element, wherein the fastening element is configured and arranged to fasten the compensation element to the valve in the valve body in a pre-stressed manner.

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.

The present disclosure relates to internal combustion engines. Various embodiments thereof may include a piezo injector for fuel injection. For example, an injector may include: a nozzle unit with a nozzle needle; a piezoelectric actuator unit; and a hydraulic coupler unit coupling the nozzle unit to the actuator unit. The coupler unit includes a coupler piston, a coupler cylinder, and a coupler spring. The coupler piston has a top side facing toward the coupler cylinder and a bottom side. The coupler spring pushes the coupler piston against a face side of the nozzle needle oriented toward the bottom side of the coupler piston and has a contact area with the nozzle needle. The coupler piston includes a passage opening providing a flow connection from the bottom side of the coupler piston to the top side of the coupler piston, arranged within the contact area.

A method and system for determining remaining useful life of an in-use injector of a reciprocating engine is disclosed. The method includes determining nozzle wear relationship data for different duty cycles of the in-use injector, and using the nozzle wear relationship data together with operating parameters for the reciprocating engine, and emission relationship data to determine actual emission levels for the in-use injector based on the wear relationship data and the emission relationship data. The method and system further include determining remaining useful life of the in-use injector based on actual emission levels and the nozzle wear relationship data; and controlling an operation of the reciprocating engine based on the actual emission levels.

A boot in a boot assembly in a fuel system includes an elongate boot body defining a longitudinal axis and having an inner boot surface. An injector portion of the boot has a window formed therein receiving an electrical connector of a fuel injector. The injector portion also includes a plurality of radially inward standoff protrusions in contact with the fuel injector to maintain an air gap clearance between an inner surface of the boot and the fuel injector.

An injection device for metering a fluid, having the following: a valve, which has a valve needle and a valve seat; a nozzle shaft, which surrounds the valve needle and which holds a volume of the fluid; and an inlet chamber, which adjoins the nozzle shaft on the side of the nozzle shaft facing away from the valve and which has a flow connection to the nozzle shaft. The injection device has at least one compressible volume compensation element, which is filled with a gas and which, within the injection device, is in contact with the fluid.

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.