A control valve assembly of a fuel injector includes a first valve arrangement wherein a first valve spool is guided in a first hydraulic bore provided in a body of the assembly. The control assembly further includes a first tubular sleeve having a seating portion which end face defines the first seating face, the first sleeve being fixed in the first hydraulic bore and the first spool extending through the sleeve.

A fuel metering valve includes a main flow path extending axially between an inlet and an outlet. Also included is a plunger disposed around a portion of a plunger guide, the plunger and the plunger guide configured to translate between an open position and a closed position to selectively distribute a fuel flowing through the main flow path to the outlet of the fuel metering valve. Further included is a solenoid coil disposed between a solenoid outer body and a solenoid inner body, the solenoid coil configured to magnetically attract the plunger to the open position. Yet further included is a secondary flow path for routing a stagnant volume of fuel upon translation of the plunger from the closed position to the open position.

An injecting apparatus for injecting a fluid under pressure into an associated chamber, the injecting apparatus including: a body, a piston movable in the body under the action of fluid pressure in the associated chamber acting from externally against the piston, the piston being operable to compress fluid to be injected in a high pressure chamber, the piston being movable against the action of fluid pressure in a control chamber whereby movement of the piston is selectively controllable by controlling the fluid in the control chamber, an injector valve and an associated injector orifice in selective fluid communication with the high pressure chamber whereby high pressure fluid from the high pressure chamber can be injected through the injector orifice upon opening of the injection valve.

A metering valve for a pump unit for feeding fuel from a tank to an internal combustion engine; the metering valve having: a sleeve having an axis A and provided with a first open end for receiving a thruster, a second opposite end provided with an opening for axially discharging the fuel and at least one side opening for feeding fuel; a plug-shaped piston housed slidably along the axis A inside the sleeve, the piston being provided with a closed end having an outer surface in contact with the thruster, an open opposite end and at least one side opening; a plug housed inside the discharge opening of the sleeve and provided with an axial opening; a spring arranged between the plug and the inner surface of the closed end of the sleeve.

A metering valve is installed in a feed passage that supplies low pressure fuel, which is fed from a feed pump, to a pressurizing chamber. The metering valve adjusts a discharge amount of the low pressure fuel discharged from the pressurizing chamber. A first pressure regulating valve is opened in a case where a pressure of the low pressure fuel becomes equal to or larger than a first preset pressure. A second pressure regulating valve is opened in a case where the pressure of the low pressure fuel becomes equal to or larger than a second preset pressure. The first pressure regulating valve and the second pressure regulating valve are configured such that a degree of responsiveness of valve opening and closing of the second pressure regulating valve is higher than a degree of responsiveness of valve opening and closing of the first pressure regulating valve.

A metering valve for a pump unit for feeding fuel from a tank to an internal combustion engine; the metering valve comprising: a sleeve having an axis A and provided with a first open end for receiving a thruster, a second opposite end provided with an opening for axially discharging the fuel and at least one side opening for feeding fuel; a plug-shaped piston housed slidably along the axis A inside the sleeve, the piston being provided with a closed end having an outer surface in contact with the thruster, an open opposite end and at least one side opening; a plug housed inside the discharge opening of the sleeve and provided with an axial opening; a spring arranged between the plug and the inner surface of the closed end of the sleeve.

An injecting apparatus for injecting a fluid under pressure into an associated chamber, the injecting apparatus including a body; a piston movable in the body under the action of fluid pressure in the associated chamber acting from externally against the piston, the piston being operable to compress fluid to be injected in a high pressure chamber, the piston being movable against the action of fluid pressure in a control chamber whereby movement of the piston is selectively controllable by controlling the fluid in the control chamber; and an injector valve and an associated injector orifice in selective fluid communication with the high pressure chamber whereby high pressure fluid from the high pressure chamber can be injected through the injector orifice upon opening of the injection valve.

An injecting apparatus for injecting a fluid under pressure into an associated chamber, the injecting apparatus including: a body, a piston movable in the body under the action of fluid pressure in the associated chamber acting from externally against the piston, the piston being operable to compress fluid to be injected in a high pressure chamber, the piston being movable against the action of fluid pressure in a control chamber whereby movement of the piston is selectively controllable by controlling the fluid in the control chamber, an injector valve and an associated injector orifice in selective fluid communication with the high pressure chamber whereby high pressure fluid from the high pressure chamber can be injected through the injector orifice upon opening of the injection valve.

A control valve assembly of a fuel injector includes a first valve arrangement wherein a first valve spool is guided in a first hydraulic bore provided in a body of the assembly. The control assembly further includes a first tubular sleeve having a seating portion which end face defines the first seating face, the first sleeve being fixed in the first hydraulic bore and the first spool extending through the sleeve.

A system includes an injector including a scheduling valve assembly and a nozzle in fluid communication with the valve assembly. The scheduling valve assembly is configured for regulation of flow from an inlet of the injector to the nozzle. The injector includes one fluid circuit between the inlet of the injector and a respective outlet of the nozzle. A solenoid valve is connected in fluid communication with the scheduling valve assembly. The solenoid valve is configured to adjust position of a hydromechanical valve spool of the valve assembly.