A control valve for controlling the movement of a needle of a fuel injector includes a coil which is attached to a housing of the injector, which housing engages with an armature which can be moved between an open position and a closed position. The armature includes a magnetic plate, through the center of which a rod, which forms a valve piston, extends perpendicularly to the plate to a remote end. The piston slides into a bore in the injector housing, the movements of the armature and of the piston opening or closing channels in which pressurized fuel flows. The armature is provided with a device for quickly discharging the fuel which is captive between the coil and the plate.

A direct injection (DI) fuel supply system includes an accumulator valve coupled to a high pressure fuel line at a position between an accumulator and a fuel rail. A controller of the DI fuel supply system is configured to control the accumulator valve to maintain the pressurized fuel housed in the fuel rail at a desired pressure and to control the accumulator valve proximate a fuel injection event by a fuel injector such that the accumulator supplies the fuel rail with approximately the portion of the pressurized fuel injected by the fuel injector during the fuel injection event. This positioning of the accumulator valve between the DI positive displacement fuel pump and the fuel rail together with active control thereof also insulates the fuel rail and the fuel injector from fuel pressure pulsations generated by the DI positive displacement fuel pump.

A fuel injection control device includes processing circuitry, which executes an estimating process to estimate pressure in first and second fuel storage members connected to first and second fuel injection valves. The estimating process includes: estimating the pressure in the first fuel storage member based on a detection value of a pressure sensor that detects the pressure in the first fuel storage member and a cycle of pulsation in the first fuel storage member, which is determined in accordance with an interval of fuel injections in a first bank; and estimating the pressure in the second fuel storage member by assuming that a phase of a periodic fluctuation of the pressure in the second fuel storage member and a phase of a periodic fluctuation of the pressure in the first fuel storage member are in antiphase.

A pre-chamber fuel admission valve includes a fuel inlet, a fuel outlet, an actuated valve, and a check valve. The fuel inlet receives a supply of a fuel. The fuel outlet delivers the fuel to a pre-chamber. The actuated valve is between and in fluid communication with the fuel inlet and the fuel outlet. The actuated valve controls a flow of the fuel from the fuel inlet to the fuel outlet. The check valve is biased in a closed position and between and in fluid communication with the actuated valve and the fuel outlet. The check valve is configured to open and allow the fuel to exit the fuel outlet in response to a fuel pressure exceeding a pre-chamber pressure plus a bias pressure, and the check valve is configured to close in response to the pre-chamber pressure plus the bias pressure exceeding the fuel pressure.

A fuel system is disclosed for use with an engine. The fuel system may have a common rail, a first type of fuel injector fluidly connected to the common rail, and a second type of fuel injector fluidly connected to the common rail. The second type of fuel injector may include a pumping portion having a bore formed therein, and a plunger reciprocatingly disposed in the bore. The second type of fuel injector may also include an accumulator portion fluidly connected to the common rail and configured to receive fuel pushed from the bore of the pumping portion by the plunger, a nozzle portion, and a valve portion fluidly connecting the pumping, nozzle, and accumulator portions.

A pressure reducing valve control apparatus is provided for a fuel supply system having a common rail and a pressure reducing valve to control rail pressure in the common rail by controlling a current supply state of the pressure reducing valve. The pressure reducing valve operates to open a valve body for discharging fuel from the common rail against a biasing force applied in a valve-closing direction by fuel-generated valve-opening force biasing the valve body in a valve-opening direction by the rail pressure and an electromagnetic force generated by current supply to an electromagnetic coil. The ECU starts to open the valve body during a period of holding a hold value by holding current supplied to the electromagnetic coil at a predetermined hold value after starting current supply to the electromagnetic coil. The ECU sets the hold value to increase as the rail pressure decreases.

A fuel injector includes a nozzle having at least one nozzle outlet. A valve needle is moveable with respect to a valve needle seating through a range of movement between a closed position and an open position to control fuel delivery through the at least one nozzle outlet. The movement of the nozzle needle is controlled by fuel pressure within a control chamber. The injector has first and second nozzle control valves for controlling fuel flow into and out of the control chamber to pressurise and depressurise the control chamber, respectively. The first nozzle control valve can operate selectively to place the control chamber in fluid communication with a fuel drain or to place the control chamber in fluid communication with a high pressure supply line. The second nozzle control valve can operate selectively to place the control chamber in fluid communication with a fuel drain.

A device and a method are provided for controlling a magnetic valve which has a coil and an armature which is displaceable by magnetic force, by means of which armature a closure element is displaceable for the purposes of injecting fuel into a combustion chamber, the method includes the steps of: energizing the coil with a voltage in accordance with a first voltage profile in order to generate a first electrical current through the coil; determining a first profile as a function of a first magnetic flux and the first current; identifying, in the first profile, a first characteristic of at least one first start of displacement at which the armature begins to displace the closure element, generating a second voltage profile and energizing the coil in accordance with the second voltage profile, such that, in a second profile, as a function of a second magnetic flux and a second current, a second characteristic of a second start of displacement is more similar to a reference characteristic than the first characteristic.

A gas injector for injecting gaseous fuel includes: a valve body; an outer needle which is a hollow needle; an inner needle disposed in a hollow region of the outer needle; and an actuator system configured to actuate the outer needle and the inner needle independently of each other in each case. A first sealing seat is provided between the valve body and the outer needle, and a second sealing seat is provided between the outer needle and the inner needle.

A hydraulic system includes a high pressure fluid source and a hydraulic actuator fluidly connected to the high pressure fluid source, and a low pressure fluid system fluidly connected to the hydraulic actuator via a fluid return line, and a hydraulic valve. The hydraulic valve includes a return spring and an elongate member, which is movably arranged in its longitudinal direction for controlling a fluid flow. The elongate member is biased to a closed position by the return spring. The elongate member forms a needle, the hydraulic valve includes a needle receiving body having a needle seat and the needle is engageable with the needle seat so as to control the fluid flow.