A fuel injector for a fuel system in an internal combustion engine includes an injector housing, a direct-operated nozzle check movable within the injector housing, a check biasing spring within a spring chamber and biasing the nozzle check toward the closed position. The injector housing defines a damping control space, an always-open vent from the spring chamber to the damping control space, and a second vent from the spring chamber to the damping control space. The fuel injector further includes a hydraulically actuated damping adjustment valve movable responsive to a pressure of fuel supplied to the fuel injector between a higher damping position blocking the second vent, and a lower damping position where the second vent is open.

A fuel injector for a fuel system in an internal combustion engine includes an injector housing, a direct-operated nozzle check movable within the injector housing, a check biasing spring within a spring chamber and biasing the nozzle check toward the closed position. The injector housing defines a damping control space, an always-open vent from the spring chamber to the damping control space, and a second vent from the spring chamber to the damping control space. The fuel injector further includes a hydraulically actuated damping adjustment valve movable responsive to a pressure of fuel supplied to the fuel injector between a higher damping position blocking the second vent, and a lower damping position where the second vent is open.

A fuel system includes a fuel injector having a fuel passage and a purging fluid passage formed therein. A nozzle tip inner surface defines a sac forming a blind end of the fuel passage in the fuel injector. A coaxial concentric check assembly includes a purging check movable to admit a purging fluid such as pressurized air into the fuel passage to purge the sac of fuel. Reduced injector dribble is observed from the purging of fuel.

A fuel system includes a fuel injector having a fuel passage and a purging fluid passage formed therein. A nozzle tip inner surface defines a sac forming a blind end of the fuel passage in the fuel injector. A coaxial concentric check assembly includes a purging check movable to admit a purging fluid such as pressurized air into the fuel passage to purge the sac of fuel. Reduced injector dribble is observed from the purging of fuel.

A fuel system includes a fuel injector having a fuel passage and a purging fluid passage formed therein. A nozzle tip inner surface defines a sac forming a blind end of the fuel passage in the fuel injector. A coaxial concentric check assembly includes a purging check movable to admit a purging fluid such as pressurized air into the fuel passage to purge the sac of fuel. Reduced injector dribble is observed from the purging of fuel.

A fuel system includes a fuel injector having a fuel passage and a purging fluid passage formed therein. A nozzle tip inner surface defines a sac forming a blind end of the fuel passage in the fuel injector. A coaxial concentric check assembly includes a purging check movable to admit a purging fluid such as pressurized air into the fuel passage to purge the sac of fuel. Reduced injector dribble is observed from the purging of fuel.

A valve assembly arrangement for an injection valve may have a central longitudinal axis, a valve assembly of the inward opening type, and a valve assembly of the outward opening type, wherein the valve assembly of the outward opening type is axially arranged adjacent and fixedly coupled to the valve assembly of the inward opening type such that the valve assembly of the inward opening type is operable to inject fluid into the valve assembly of the outward opening type for increasing a fluid pressure in the valve assembly of the outward opening type to open the valve assembly of the outward opening type to enable dispensing of the fluid from the valve assembly arrangement.

A valve assembly arrangement for an injection valve may have a central longitudinal axis, a valve assembly of the inward opening type, and a valve assembly of the outward opening type, wherein the valve assembly of the outward opening type is axially arranged adjacent and fixedly coupled to the valve assembly of the inward opening type such that the valve assembly of the inward opening type is operable to inject fluid into the valve assembly of the outward opening type for increasing a fluid pressure in the valve assembly of the outward opening type to open the valve assembly of the outward opening type to enable dispensing of the fluid from the valve assembly arrangement.

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

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