An electromagnetic valve used in a fuel system, in which at least a portion of a member constituting an magnetic circuit in an electromagnetic drive unit includes 0.15-0.45 mass % (inclusive) Ni, 0.65-1.0 mass % (inclusive) Al, 9.2-10.3 mass % (inclusive) Cr, and 0.90-1.6 mass % (inclusive) Mo, and the remainder comprises an alloy material comprising Fe and unavoidable impurities. The alloy material may further include 0.05-0.15 mass % (inclusive) Pb.

A fuel pump, is disclosed, including a power group having a housing, a coil, a pole piece and a movable armature; a valve group including a valve body, a plunger connected to the armature, a bushing in which the plunger is disposed, an inlet chamber, an outlet chamber, a pump chamber, an inlet valve disposed between the inlet chamber and the pump chamber and an outlet valve disposed between the pump chamber and the outlet valve; and an inlet filter coupled to a fluid inlet of the valve group. The inlet filter is disposed relative to the coil such that when the fuel pump is disposed within a fuel tank, a bottom of the inlet filter as oriented in the fuel tank is disposed above a fuel level in the fuel tank and the coil is at least partly submerged in the fuel.

A movable core is driven by a magnetic attraction force with a fixed core to move a valve body to inject fuel. A yoke accommodates the fixed core. A coil is in a coil chamber between the fixed core and the yoke. The coil chamber is filled with a filling resin member being electrically insulative. The fixed core has a core facing surface facing the movable core and includes a protruding portion that protrudes radially outer side and is in contact with the yoke to conduct the magnetic flux. A resin molding flow channel is formed in the protruding portion to cause molten resin serving as the filling resin member to flow into the coil chamber. A length of the protruding portion along a cylinder center line is set to be shorter toward a radially outer side.

Disclosed are example embodiments of a fuel injection device having a plunger that moves at a predetermined reciprocating motion from an initial position, the fuel injection device includes: an electromagnetic coil; a tubular bobbin within the electromagnetic coil, wherein the electromagnetic coil is configured to move the tubular bobbin when energized; a fuel intake channel; and an inlet check valve disposed along a fuel pathway of the fuel intake channel, the inlet check valve configured to allow fuel to flow through and to a pressurization chamber, wherein the inlet check valve is a normally open valve.

A fuel injector is provided. The fuel injector includes a sleeve having a first end proximate an outlet; a piston slidingly received in the sleeve, the piston having a first end proximate the outlet; a pumping chamber at least partially defined by the sleeve between the first end of the piston and the outlet; and a normally-open inlet valve through which fuel passes to enter the pumping chamber.

Disclosed are example embodiments of a fuel injection device having a plunger that moves at a predetermined reciprocating motion from an initial position, the fuel injection device includes: an electromagnetic coil; a tubular bobbin within the electromagnetic coil, wherein the electromagnetic coil is configured to move the tubular bobbin when energized; a fuel intake channel; and an inlet check valve disposed along a fuel pathway of the fuel intake channel, the inlet check valve configured to allow fuel to flow through and to a pressurization chamber, wherein the inlet check valve is a normally open valve.

In a fuel injection device, a driving unit structure has a magnetic aperture, in which an inner diameter is gradually enlarged toward the mover side, provided in an inner peripheral surface of the magnetic core. It is possible to reduce magnetic delay time upon valve opening from the supply of the electric current to the coil to the rise of magnetic flux and magnetic delay time upon valve closing from the stoppage of the electric current to the coil to reduction of magnetic flux, by providing a magnetic aperture in the inner peripheral surface of the magnetic core. Thus it is possible to improve the dynamic responsiveness upon valve opening and valve closing.

A valve assembly for a fluid pump includes a valve body; an inlet disk movably disposed in the valve body; an outlet disk movably disposed in the valve body; and a valve seat fixed within the valve body. The valve seat includes a first aperture defined axially through the valve seat in a radial central portion thereof, and one or more second apertures disposed at least partly around the first aperture. The inlet disk is biased in a closed position against the valve seat along a first surface thereof, the closed position of the inlet disk covering the one or more second apertures of the valve seat. The outlet disk is biased in a closed position against the valve seat along a second surface thereof.

In a fuel injection device, a driving unit structure has a magnetic aperture, in which an inner diameter is gradually enlarged toward the mover side, provided in an inner peripheral surface of the magnetic core. It is possible to reduce magnetic delay time upon valve opening from the supply of the electric current to the coil to the rise of magnetic flux and magnetic delay time upon valve closing from the stoppage of the electric current to the coil to reduction of magnetic flux, by providing a magnetic aperture in the inner peripheral surface of the magnetic core. Thus it is possible to improve the dynamic responsiveness upon valve opening and valve closing.

A fuel injection valve includes: a movable arrangement that is coupled to a movable core and a needle while a movable flow passage, which forms a part of a flow passage of the fuel injection valve, is formed at an inside of the movable arrangement; and a valve main body that receives the movable arrangement. The movable arrangement has: a first flow-restricting portion that reduces a cross-sectional area of a portion of the movable flow passage; and a second flow-restricting portion that is spaced away from the first flow-restricting portion and reduces a cross-sectional area of another portion of the movable flow passage to a cross-sectional area that is equal to or larger than a cross-sectional area of the first flow-restricting portion. A distance between the first flow-restricting portion and the second flow-restricting portion is larger than an equivalent diameter of the cross-sectional area of the second flow-restricting portion.