Abstract: A fuel injector has a swirl generator located downstream from a valve seat. A fuel injection hole is connected to a downstream side of the swirl generator. The swirl generator includes a swirl chamber having an involute or a spiral shape and the fuel injection hole bored at a bottom or the swirl chamber and a swirl generation use passage connected to the upstream side of the swirl chamber for introducing fuel into the swirl chamber. The bottom of the swirl chamber is provided with a step height so as to make a level difference in which the bottom of the swirl chamber is lower than a bottom of the swirl generation use passage, and the step height is formed at a position where fuel flowing into the swirl chamber from the swirl generation use passage meets fuel turning in the swirl chamber.

Abstract: A fuel injection valve realizing improved circumferential uniformity of swirling fuel is provided. The fuel injection valve includes swirling chambers each having an inner peripheral wall whose curvature is gradually larger from upstream to downstream, paths for swirling each of which, having a fuel flow-in region formed along a valve axis direction, guides fuel to the associated one of the swirling chambers, and fuel injection orifices open into the associated swirling chambers, respectively. In the fuel injection valve, the paths for swirling are interconnected in a central portion of an orifice plate and are smaller in height toward where they are interconnected.

Abstract: A fuel injection valve realizing improved circumferential uniformity of swirling fuel is provided. The fuel injection valve includes a swirling chamber having an inner peripheral wall whose curvature is gradually larger from upstream to downstream, a path for swirling which, having a fuel flow-in region formed along a valve axis direction, guides fuel to the swirling chamber, and a fuel injection orifice open into the swirling chamber. In the fuel injection valve, the path for swirling is inclined toward the fuel injection orifice formed on a downstream side of the swirling chamber.

Abstract: A fuel injection valve realizing improved circumferential uniformity of swirling fuel is provided. The fuel injection valve includes swirling chambers each having an inner peripheral wall whose curvature is gradually larger from upstream to downstream, paths for swirling each of which, having a fuel flow-in region formed along a valve axis direction, guides fuel to the associated one of the swirling chambers, and fuel injection orifices open into the associated swirling chambers, respectively. In the fuel injection valve, a curved portion is formed on the bottom, in a sectional view along the valve axis direction, of an inlet portion of each of the paths for swirling so as to change the fuel flow in each of the paths for swirling.

Abstract: A fuel injection valve which ensures improved uniformity of a swirl flow in a circumferential direction. It includes: a valve element provided movably; a nozzle body with an opening downstream, including a valve seat face for the valve element to rest on in a valve closed state; a swirling path communicating with the opening of the nozzle body, located downstream of the opening; a swirling chamber located downstream of the swirling path, in which fuel is swirled and given a swirling force; and a fuel injection hole formed at the bottom of the swirling chamber to inject fuel outward. The swirling chamber has an inner wall surface which makes a spiral curve. The swirling chamber and the fuel injection hole are formed so that the center of a base circle for the spiral curve coincides with the center of the fuel injection hole.

Abstract: A fuel injection valve is disclosed with enhanced uniformity of a swirl flow in the circumferential direction. The valve includes a swirling chamber having an inner wall surface with a helical curve and a swirling passage for guiding fuel into the chamber. The valve is formed such that the center of a circle as the basis of the helical curve and the center of a fuel injection hole open in the swirling chamber align with one another. The joint between the passage for swirling and the inner circumferential wall on the downstream side of the chamber at which both walls intersect is positioned between a line from the center of the hole to a point at which the curvature of the swirling chamber shape starts to change; and a tangent line of the side wall of the hole so drawn that it is in parallel to the line segment.

Abstract: An object of the present invention is to provide a fuel injection valve that is made superior in atomization performance by preventing an influence of minute deformation occurring when an orifice plate is assembled to a nozzle body, thereby reducing fuel leakage from a swirling passage to increase the strength of a swirl flow. The valve includes a valve body openable and closable to jet fuel; a nozzle body having a valve seat surface capable of coming into contact with the valve body to block the jet of fuel; and an orifice plate disposed downstream of the valve seat surface and having a plurality of fuel injection holes adapted to jet swirl fuel. The nozzle body has an end face portion with a downwardly convex inclined surface.

Abstract: A fuel injection valve which has: swirl chambers each having an inner wall whose curvature is gradually increased from upstream to downstream along fuel flow; passages for swirling motion, the passages permitting introduction of fuel into the swirl chambers; fuel injection holes opening into the swirl chambers and including at least two narrow-angle injection holes and a wide-angle injection hole from which at least two narrow-angle sprays and a wide-angle spray are respectively ejected; and an orifice plate provided with the injection holes. The narrow-angle injection holes are spaced a given distance from the center of the orifice plate. The wide-angle injection hole is formed on a line perpendicularly intersecting a line segment that interconnects the centers of the narrow-angle injection holes.

Abstract: An injector used for an internal combustion engine includes a valve needle which closes a fuel passage by contacting a valve seat and opens the fuel passage by separating from the valve seat. A coil and a magnetic core are provided to drive the valve needle, and an anchor is held in a relatively displaceable state with respect to the valve needle. A first biasing device biases the valve needle in a direction opposite to a direction of a drive force, and a second biasing device biases the anchor in the direction of the drive force with a set load smaller than that of the first biasing device. A restricting feature restricts relative displacement of the anchor with respect to the valve needle in the direction of the drive force.

Abstract: A fuel injector has a swirl generator located downstream from a valve seat. A fuel injection hole is connected to a downstream side of the swirl generator. The swirl generator includes a swirl chamber having an involute or a spiral shape and the fuel injection hole bored at a bottom or the swirl chamber and a swirl generation use passage connected to the upstream side of the swirl chamber for introducing fuel into the swirl chamber. The bottom of the swirl chamber is provided with a step height so as to make a level difference in which the bottom of the swirl chamber is lower than a bottom of the swirl generation use passage, and the step height is formed at a position where fuel flowing into the swirl chamber from the swirl generation use passage meets fuel turning in the swirl chamber.

Abstract: A method of controlling a fuel injection device that can control a small amount of injection is provided. A fuel injection device for use in an internal combustion engine, includes: a valve body that can open and close a fuel passage, a needle that transfers a force with the valve body, and executes valve opening/closing operation, and an electromagnet that includes a coil and a magnetic core provided as a driver for driving the needle, and a cylindrical nozzle holder disposed on an outer periphery of the magnetic core and the needle, in which a current is supplied to the coil to exert a magnetic attractive force between the magnetic core and the needle to open the valve body.

Abstract: 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.

Abstract: The drive device is configured to, during a time interval between an earlier fuel injection (first fuel injection) and a later fuel injection (second fuel injection), supply an electromagnetic coil with an intermediate current at a voltage with a level of not opening the valve. Further, the drive device sets a voltage application for supplying the intermediate current to initiate before a valve closing in the earlier fuel injection and terminate before half a period of time between a first instant when the valve is closed in the earlier fuel injection and a second instant when a supply of a drive current for opening the valve is initiated in the later fuel injection.

Abstract: A fuel injection valve includes: a swirl chamber having an inner peripheral wall formed to be gradually increased in curvature toward a downstream side from an upstream side; a swirl passage, through which a fuel is introduced into the swirl chamber; and a fuel injection port opened to the swirl chamber, wherein the swirl chamber and the swirl passage are formed so that a side wall of the swirl passage connected to a downstream end side of the swirl chamber, or an extension thereof is made not to intersect a downstream side portion of the inner peripheral wall of the swirl chamber, or an extension thereof.

Abstract: There is provided a fuel injection valve, in which uniformity in swirl intensity in a peripheral direction of a swirl fuel is heightened. A fuel injection valve comprises a valve element 3 and a valve seat 10, which cooperate to open and close a fuel passage to perform injection of a fuel and stoppage of injection, a nozzle body 4 having the valve seat 10, a swirl passage 21 provided downstream of a seat portion 10a, on which the valve element 3 and the valve seat 10 contact with each other, and a swirl chamber 22, to which the swirl passage 21 and a fuel injection port 23 are connected, and a recess (buffer) 24 for enlargement of the swirl chamber 22 in volume is provided on a wall surface portion 4a of the swirl chamber 22 opposed to the fuel injection port 23.

Abstract: An object of the present invention is to reduce the pressure loss in a relief valve employed for a high-pressure liquid supply pump. Disclosed is a high-pressure liquid supply pump for pressurizing a liquid and supplying the pressurized liquid from a low-pressure side to a high-pressure side. The pump includes a relief path which releases the pressurized liquid from the high-pressure side to the low-pressure side, and a relief valve which is positioned in the relief path and equipped with an intermediate chamber, a valve seat positioned toward the high-pressure side of the intermediate chamber, a ball valve that is attachable to and detachable from the valve seat, and a ball valve retainer for pressing the ball valve against the valve seat. The relief path is configured so that an inflow path to the intermediate chamber and an outflow path from the intermediate chamber both produce a restriction effect.

Abstract: A fuel injection valve comprises a valve seat, a movable valve element which is seated on or separated from the valve seat, and a nozzle member having a plurality of nozzle holes. At least one of the valve element and valve seat has a curved surface at a contact position where they contact with each other when the valve element is seated on the valve seat. Two or more of the nozzle holes are provided outside an intersection line of a virtual extension surface along a tangential line to the curved surface at the contact position and a surface of the nozzle member.

Abstract: An injector used for an internal combustion engine includes a valve needle which closes a fuel passage by contacting a valve seat and opens the fuel passage by separating from the valve seat. A coil and a magnetic core are provided to drive the valve needle, and an anchor is held in a relatively displaceable state with respect to the valve needle. A first biasing device biases the valve needle in a direction opposite to a direction of a drive force, and a second biasing device biases the anchor in the direction of the drive force with a set load smaller than that of the first biasing device. A restricting feature restricts relative displacement of the anchor with respect to the valve needle in the direction of the drive force.

Abstract: An electromagnetic fuel injection valve device for an internal combustion engine is configured to carry out an energization to an electromagnetic coil of an injection valve actuator for a valve opening motion and additionally carry out a mid-term energization at a time interval between both an energization for valve opening of a previous fuel injection and an energization for valve opening of a subsequent fuel injection. A current of the mid-term energization is smaller than a current of the energization for valve opening motion and has the same direction as a direction of the current of the energization for valve opening motion.

Abstract: A fuel injection nozzle for directly injecting fuel into a cylinder of an internal combustion engine is inserted in a connecting pipe extending from a fuel rail and is fixed to the connecting pipe by fastening member. The fuel injection nozzle has a sealing part for sealing a fuel passage to prevent fuel leakage, and a contact part in contact with the fastening member. The contact part is softer than the fastening member, and the contact part undergoes plastic deformation when a bending moment that bends the axis of the fuel injection nozzle acts on the fuel injection nozzle.