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 injector includes an injector body and a valve stack within the injector body that includes a valve seat plate. The valve seat plate includes a pressure control passage for controlling fuel injection, and a valve seat positioned fluidly between the pressure control passage and a low-pressure drain. The valve seat plate includes a pressure-limiting annular groove that extends circumferentially around the valve seat and axially inward from a side of the valve seat plate where the valve seat is located. The groove enables deformation in response to pressure differences across the valve seat plate in a manner that limits stress concentrations.

Provided is a fuel injection valve capable of stroking a valve body in two stages of large and small strokes and improving responsiveness of a valve opening operation. Therefore, a first mover 201 is attracted to a magnetic core 107. A second mover 202 is formed separately from the first mover 201, and is attracted to the magnetic core 107 on an inner diameter side of the first mover 201. A valve body 101 has a flange portion 101a on an upstream side of the second mover 202. A spacer 213 forms a gap (void g1) in an axial direction between the flange portion 101a and the second mover 202 in a valve closed state.

The invention relates to an electromagnetically actuatable metering valve for liquids and/or gases, comprising: a valve housing (1); a valve seat element (2) which is connected to the valve housing (1) and in which at least one outlet opening (3) is formed; and a magnetic armature (4) which can move in a stroke-like manner relative to the valve seat element (2) and which is securely connected to a plate- or disc-shaped valve closing element (5) for opening and closing the at least one outlet opening (3) or which forms same; as well as a magnetic core (6) opposite the magnetic armature (4) at a working air gap (14) and at least one spring (7) pretensioning the magnetic armature (4) and the valve closing element (5) in the closing direction. According to the invention, the magnetic armature (4) and the valve closing element (5) are loaded in a targeted asymmetrical manner and/or are shaped in a targeted asymmetrical manner The invention also relates to a method for operating a metering valve for liquids and/or gases.

An object of the present invention is to provide a fluid control device with an improved effect of suppressing blowhole generation. Therefore, a component for a flow rate control device of the present invention includes: a first component 140 (A); a second component 107 (B) fixed to the first component by a press-fitting portion 802; a butt-welded portion 803 connecting the first component and the second component; and a first gap 1001 and a second gap 1002 formed between mutually opposing surfaces of the first component and the second component. The first gap is provided on a side of the press-fitting portion with respect to the second gap between the press-fitting portion and the butt-welded portion, and is formed in a direction intersecting a press-fitting direction. The second gap is provided on a side of the butt-welded portion with respect to the first gap between the press-fitting portion and the welded portion, and is formed in a direction intersecting the first gap.

A fuel injection valve configured to inject fuel from an injection hole includes: a coil that is configured to generate a magnetic flux when the coil is energized; a stationary core that forms a portion of a flow passage, which is configured to conduct the fuel to the injection hole, wherein the stationary core is configured to become a passage of the magnetic flux; a movable core that is configured to be attracted toward the stationary core when the movable core becomes a passage of the magnetic flux; a passage forming portion that is placed on a downstream side of the stationary core and forms a portion of the flow passage; and a covering portion that covers a stationary boundary, which is a boundary between the passage forming portion and the stationary core, from a flow passage side of the stationary boundary where the flow passage is located.

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.

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.

Provided is a fuel injection valve capable of stroking a valve body in two stages of large and small strokes and improving responsiveness of a valve opening operation. Therefore, a first mover 201 is attracted to a magnetic core 107. A second mover 202 is formed separately from the first mover 201, and is attracted to the magnetic core 107 on an inner diameter side of the first mover 201. A valve body 101 has a flange portion 101a on an upstream side of the second mover 202. A spacer 213 forms a gap (void g1) in an axial direction between the flange portion 101a and the second mover 202 in a valve closed state.

An object of the present invention is to provide a fluid control device with an improved effect of suppressing blowhole generation. Therefore, a component for a flow rate control device of the present invention includes: a first component 140 (A); a second component 107 (B) fixed to the first component by a press-fitting portion 802; a butt-welded portion 803 connecting the first component and the second component; and a first gap 1001 and a second gap 1002 formed between mutually opposing surfaces of the first component and the second component. The first gap is provided on a side of the press-fitting portion with respect to the second gap between the press-fitting portion and the butt-welded portion, and is formed in a direction intersecting a press-fitting direction. The second gap is provided on a side of the butt-welded portion with respect to the first gap between the press-fitting portion and the welded portion, and is formed in a direction intersecting the first gap.