An outlet and pressure relief valve assembly for a fuel pump includes a housing which extends along an axis from an inner end to an outer end. The housing has a bore which extends thereinto along the axis from the inner end. A valve seat is located within the bore and has an end wall which is transverse to the axis and also has a sidewall which is annular in shape and extends away from the end wall. An outlet flow passage extends through the end wall such that the outlet flow passage is centered about the axis. A pressure relief flow passage extends through the end wall such that the pressure relief flow passage is laterally spaced from the outlet flow passage. An outlet valve member is located within the valve seat sidewall and a pressure relief valve member is located between the valve seat and the inner end.

The present disclosure relates to a fuel injector for injecting fuel into a combustion engine. It may comprise a valve with a movable needle, two springs pushing the needle toward the closed position, and an actuator for opening the valve. The needle may be in a fuel reservoir of a valve body. The actuator may supply pressurized fuel to the fuel reservoir so that the fuel pressure forces the needle away from the closed position against the spring force of the first spring or the first and second springs, respectively. There may be play between the second spring and the needle when the needle is in the closed position.

A fuel injection valve includes a valve body, a fixed core, a movable core, a spring, and a cup. The spring is elastically deformed according to valve opening operation of the valve body, and exerts a valve closing elastic force for closing the valve body. The cup contacts a valve closing contact surface of the valve body, and transmits the valve closing elastic force to the valve body. At a start of predetermined-distance movement of the movable core together with the cup, the cup is in contact with the valve closing contact surface, and the valve body or the cup has a supply flow channel through which fuel is supplied to the valve body closing contact surface which is in a state contacting the cup.

A high-pressure fuel pump includes a pressure-limiting valve that opens from a high-pressure region of the high-pressure fuel pump towards a compression chamber or towards a low-pressure region of the high-pressure fuel pump. The pressure-limiting valve includes a valve body with a valve seat surface that tapers against the opening direction of the pressure-limiting valve, a spherical valve element, and a valve spring, which presses the spherical valve element against the opening direction of the pressure-limiting valve towards the valve seat surface. When the pressure-limiting valve is closed, the valve element and the valve seat surface bear against one another over a contact line, and a gap is formed between the valve element and valve body, next to the contact line. This gap is asymmetrically narrower upstream of the contact line than downstream of the contact line.

Various methods and systems are provided for a fuel injector. In one example, a fuel injector includes a nozzle tip including a plurality of injection holes, a first needle biased against the nozzle tip via a first biasing member positioned within a first control volume, and a second needle surrounding a portion of the first needle and biased against the first needle and the nozzle tip via a second biasing member positioned within a second control volume. A needle actuator may be energized for different durations of time in order to move one or more of the first needle and the second needle relative to the nozzle tip.

A fuel injector has means to directly inject one type of fuel or two types of fuels collectively with fuel ratios on demand. Once being used as a single fuel injector, the injector can enable injection rate shaping. Once being used as a dual fuel injector, the injector can tailor fuel properties on demand. The fuel injector has the capability to enable tailored chemical and thermal-physical fuel properties to enable high efficiency clean combustion for different engine loads and speeds.

A combination outlet valve and pressure relief valve includes an outer housing having a passage. An inner housing is located within the passage and includes a first bore extending thereinto from one end and a second bore extending thereinto from the other end such that the first bore and the second bore terminate at an inner housing wall. An outlet valve assembly is located within the first bore and includes an outlet valve member, an outlet valve seat, and an outlet valve spring grounded to the inner housing wall and biasing the outlet valve member toward the outlet valve seat. A pressure relief valve assembly is located within the second bore and includes a pressure relief valve member, a pressure relief valve seat, and a pressure relief valve spring grounded to the inner housing wall and biasing the pressure relief valve member toward the pressure relief valve seat.

An injection valve may include: a valve needle moving from a closed position to an open position; a calibration spring biasing the needle towards the closed position; an armature moving toward the pole piece to take the valve needle towards the open position with respect to the valve needle; and a pole piece. Some valves include a magnetic ring moving between a first position, with a top side spaced apart from the pole piece and an underside in contact with the valve needle, and a second position where the top side is in contact with the pole piece. A second spring is in parallel to the calibration spring. An upper retaining element connected to a shaft extends in radial direction to limit movement of the armature relative to the valve needle so that the armature connects to the upper retaining element to displace the valve needle towards the open position.

A coil assembly in a fuel injector includes a magnetic core and; a winding wound around the core, the winding being overmoulded and forming a cylindrical overmoulding. An axial blind hole extends towards the interior of the coil assembly from a first surface to a distal end, the blind hole being suitable for housing at least one spring for loading a magnetic armature. The coil assembly is provided with a degassing hole passing through the core and the overmoulding from the blind axial hole to an axial outer cylindrical surface, the degassing hole being provided in the magnetic core and having a restriction that is arranged in a first section that is proximal to the blind axial hole.

A fuel injection valve includes: a circular plate portion that is abuttable against an end surface of a needle opposite from a valve seat while the needle being provided to open and close an injection hole upon lifting and seating of the needle relative to the valve seat; and a tubular portion that extends from the circular plate portion toward the valve seat and has an end part, which is opposite from the circular plate portion and is abuttable against a movable core second contact surface of a movable core opposite from the valve seat. In a state where the circular plate portion abuts against the needle, and the tubular portion abuts against the movable core, a gap is formed between a flange member end surface of a flange of the needle and a movable core first contact surface of the movable core opposite from the valve seat.