A dual-fuel fuel injector, having: a first nozzle needle for discharge of liquid fuel via a first nozzle arrangement; and a multiplicity of second nozzle needles, arranged around the first nozzle needle and controlled in terms of axial stroke, for discharge of gaseous fuel via a second nozzle arrangement. Each of the second nozzle needles has for controlling the stroke thereof, a respective control chamber in the injector which can be charged with and relieved of pressure by a control fluid. The dual-fuel fuel injector has an annular duct which can be charged with and relieved of pressure by the control fluid. The dual-fuel fuel injector is designed such that, for controlling the stroke of the second nozzle needles, the control chambers for the second nozzle needles are charged with and relieved of pressure by the control fluid proceeding from the annular duct.

A fuel valve includes a housing, a nozzle with nozzle holes opening to a volume inside the nozzle at the front end of the housing, a gaseous fuel inlet port in the housing connected to high pressure gaseous fuel, an axially displaceable valve needle received in a longitudinal bore in the housing, and rests on a valve seat in a closed position and has lift from the valve seat in an open position, the valve seat placed between a fuel chamber and an outlet port, the fuel chamber connected to the fuel inlet port, the outlet port connected to the volume in the nozzle, an actuator system for moving the needle between the closed and open positions, an ignition liquid inlet port connected to high pressure ignition liquid, and conduit connecting the ignition liquid inlet port to the fuel chamber, the conduit including a fixed flow restriction.

An electrically actuated control valve has three mouths and three operating positions, in which the three mouths includes a first mouth for inlet of a working fluid, and a second mouth and a third mouth for outlet of the working fluid. The three operating positions include a first operating position in which a passage of fluid from the first mouth to the second mouth and the third mouth is enabled, a second operating position in which a passage of fluid from the first mouth to only one of said second and third mouths is enabled, and a third operating position in which the passage of fluid from the first to the second mouth and the third mouth is disabled. The control valve includes an electric or electromagnetic actuator for controlling the passage of fluid from the first mouth to the second and third mouths providing the aforesaid three operating positions.

The invention relates to a fuel injector (1) for operating with combustible gas. The fuel injector has a plurality of combustible-gas nozzle valve elements (9), and the stroke of each of the combustible-gas nozzle valve elements can be controlled by means of a paired hydraulic piston control assembly (55) of the fuel injector, wherein each piston control assembly is formed by two control chambers (59, 61) and a piston section (63) on the combustible-gas nozzle valve element paired with the piston control assembly, said piston section separating the control chambers in such a way that their volumes can be varied, and the fuel injector is designed to control the stroke of the combustible-gas nozzle valve elements in tandem using a 3/2-way valve (67), by means of which the hydraulic pressure in one of the two control chambers of the piston control assemblies is controlled.

The invention relates to a fuel injector (1) for operating with combustible gas. The fuel injector has a plurality of combustible-gas nozzle valve elements (9), and the stroke of each of the combustible-gas nozzle valve elements can be controlled by means of a paired hydraulic piston control assembly (55) of the fuel injector, wherein each piston control assembly is formed by two control chambers (59, 61) and a piston section (63) on the combustible-gas nozzle valve element paired with the piston control assembly, said piston section separating the control chambers in such a way that their volumes can be varied, and the fuel injector is designed to control the stroke of the combustible-gas nozzle valve elements in tandem using a 3/2-way valve (67), by means of which the hydraulic pressure in one of the two control chambers of the piston control assemblies is controlled.

A fuel injector capable of injecting a plurality of different fuels in a single fuel injection event includes a body including a primary fuel path and a pilot fuel path and a first plunger in fluid communication with the pilot fuel path. The fuel injector also includes a second plunger in fluid communication with the primary fuel path and with the pilot fuel path, a hydraulic control chamber within the pilot fuel path, and an injection valve at which the primary fuel path and the pilot fuel path connect to each other.

A fuel injection system for an aircraft engine has: a first fuel injector having a first actuation inlet, a first fuel inlet connected to a fuel source, and a first fuel outlet connected to the at least one combustion chamber, the first fuel injector defining a first pressure ratio; a second fuel injector having a second actuation inlet, a second fuel inlet connected to the fuel source, and a second fuel outlet connected to the at least one combustion chamber, the second fuel injector defining a second pressure ratio; and an actuation fluid system having a circuit connected to the first actuation inlet and to the second actuation inlet, the first outlet pressure different than the second outlet pressure by having one or both of the first pressure ratio different than the second pressure ratio and a first actuation pressure different than a second actuation pressure.

A fuel system includes a plurality of fuel injectors each having an injection control valve assembly, a direct operated nozzle check, a high pressure nozzle supply passage, and a check control chamber. A common drain conduit fluidly connects to each of the plurality of fuel injectors to receive drained actuating fluid. A plurality of pressure regulating valves each having a static geometry are positioned fluidly between the common drain conduit and the check control chamber in one of the plurality of fuel injectors. Operating a fuel system according to the present disclosure includes limiting cross-talk between injectors in the fuel system.

A fuel system includes a plurality of fuel injectors each having an injection control valve assembly, a direct operated nozzle check, a high pressure nozzle supply passage, and a check control chamber. A common drain conduit fluidly connects to each of the plurality of fuel injectors to receive drained actuating fluid. A plurality of pressure regulating valves each having a static geometry are positioned fluidly between the common drain conduit and the check control chamber in one of the plurality of fuel injectors. Operating a fuel system according to the present disclosure includes limiting cross-talk between injectors in the fuel system.

The invention relates to a fuel injector arrangement (1) comprising a number of fluid supply paths (29, 31, 39), namely, a first (29), a second (31) and a third fluid supply path (39). The fuel injector arrangement (1) has a first switching device (43) in the second fluid supply path (31). Said first switching device, controlled by the fluid pressure in the third fluid supply path (39), opens or blocks the second fluid supply path (31). The fuel injector arrangement (1) has a second switching device (49) in the first fluid supply path (29). Said second switching device, controlled by the fluid pressure downstream of the first switching device (43) in the second fluid supply path (31), opens or blocks the first fluid supply path (29).