Abstract: A control valve includes a main body, the first coil assembly arranged on the first side of the main body and having the first contact surface and the first through hole extending from the first contact surface, the second coil assembly arranged on the second side of the main body and having the second contact surface and the second through hole extending from the second contact surface, and a spool arranged within the main body and configured to move between the first and second contact surfaces. The spool has the third contact surface facing the first contact surface, the fourth contact surface facing the second contact surface, and the third through hole extending from the third contact surface to the fourth contact surface.

Abstract: A solenoid armature for a solenoid actuator, including at least one magnetic region and at least one non-magnetic region, the solenoid armature being configured as a one-piece component having a first and second armature end face, the magnetic and non-magnetic regions being integrally bonded to each other by a two-component powder injection molding technique, and the magnetic region and the non-magnetic region extending in the axial direction at least as far as the first armature end face.

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: In a fuel injector for injecting fuel into a combustion chamber of an internal combustion engine, an injection valve member for opening and closing at least one injection opening is triggered by a control valve embodied as a magnet valve. On the armature of the magnet valve, a sealing face is embodied that for closing the control valve is positionable into a valve seat. The armature of the magnet valve is movable, without armature guidance, between an upper and a lower stroke stop. Because the sealing face, which for closing the control valve is positionable into the valve seat, is embodied on the armature, an additional closing element of the kind provided in the prior art can be dispensed with.

Abstract: Oil intensified common rail injectors that combine a common-rail non-intensified injector with an oil-intensified injector. The invention also uses fuel (common rail) pumps that are commercially available since the injector does not rely on this pump for intensification function. Also, since the pressure of the fuel pump is limited to lower than the intensified pressure, the injected pressure is limited to the unit injector; this eases the rail and tube requirements to this lower fuel rail pressure. The injector operates up to this limited pressure with no intensification. Also a separate oil system is configured to operate a hydraulic intensifier. Thus the system is able to achieve very high injection pressure without common rail pump, rail, fitting and jumper tube limits. The oil system does not need to operate or run unless these elevated pressures are required. Embodiments using direct needle control are disclosed.

Abstract: A fuel injector includes a piezoelectric actuation mechanism and a sensor configuration to measure the condition of the actuation mechanism as well as an associated fuel rail. The sensor configuration includes a piezoelectric sensor with an output signal with significantly reduced distortion that accurately reflects control signals provided to the piezoelectric actuation mechanism.

Abstract: A fuel injection valve with reduced adhesion of deposits to a fuel injecting portion and superior in durability is provided. Also provided is a method for machining multi-orifice type fuel injecting portions easily, less expensively, in good surface roughness, in high productivity, and with few variations in shape, accuracy and surface roughness, using inexpensive equipment. The surface roughness of fuel injecting portions comprising orifices and apertures is made Rz 2 ?m or less. Apertures are formed by press working so as to each have a plastic-worked surface of Rz 0.2 ?m or less in surface roughness and then orifices are formed in the bottoms of the apertures so as to have a plastic-worked surface of Rz 0.2 ?m or less in surface roughness. Further, when abrasion resistance of the nozzle is required, the fuel injecting portions are finished to a surface roughness of Rz 2 ?m by quenching.

Abstract: The present invention relates to an actuator arrangement for use in a fuel injector, comprising: a piezoelectric actuator having a body section, said body section having a first end piece and a second end piece; a rigid encapsulation member which encloses the body section and the end pieces, wherein potting material is fitted between the rigid encapsulation member and the body section, wherein the first end piece is slideably fitted into the rigid encapsulation and the second end piece is fixed to or integrated into the encapsulation member.

Abstract: A high-pressure fuel injection valve may include a control valve having an actuator, a high-pressure fuel connection and a low-pressure fuel connection. A control plunger and nozzle needle are aligned longitudinally in the valve stem and the valve tip. Together with the control plunger, the receiving chamber of the control plunger forms a closing control chamber delimited by the upper control plunger surface, and an opening control chamber delimited by the lower control plunger surface. Each control chamber is hydraulically connected via a feed throttle to the high-pressure fuel connection and via a return throttle to the low-pressure fuel connection. The control valve opens and closes the fuel return between the return throttles and the low-pressure fuel connection depending on the operation. The flow values of the feed throttles and of the return throttles are selected such that the high-pressure fuel injection valve opens and closes based on actuation of the control valve.

Abstract: A fuel injector (10) includes an inlet tube (20). A valve body (12) is associated with the inlet tube to define a fuel passage (23). A valve seat (14) is associated with the valve body and defines an outlet opening (18). An armature (42) is movable with respect to the valve body between a first position and a second position. The armature is associated with a closure member (18) that opens and closes the outlet opening. An electromagnetic coil (40) is energizable to provide magnetic flux that moves the armature between the first and second positions to control fuel flow through the outlet opening. A heat exchanger (50) is provided in the inlet tube and a secondary coil (46) is energizable to provide a magnetic field to inductively heat the heat exchanger and thus fuel prior to exiting the outlet opening.

Abstract: At the downstream-side face of an injection hole plate, a plurality of concaves are arranged corresponding to a plurality of injection holes; at least part of an injection hole outlet opens at the plain of the concave; the rest of the outlet opens at the downstream side face of the injection hole plate or contacts the inner surface of the concave. In a flow path formed by the injection hole, there is provided a cylindrical portion, whose cross section is the radially minimum cross section of the injection hole, from the upstream side face of the injection hole plate to the plain of the concave. Where D1 denotes the diameter of the injection hole and D2 denotes the diameter of the concave or the diameter of the concave in the circumferential direction of the virtual circle, the relationship 1.1<(D2/D1)<3.0 is satisfied.

Abstract: A fuel injector for an engine is disclosed. The fuel injector may have a fuel nozzle with at least one injection orifice, and a needle element movable within the fuel nozzle between a first position at which the needle element inhibits fuel flow and a second position at which fuel flow is substantially uninhibited. The fuel injector may also have a control chamber located at a base end of the needle element, a body, and a control valve disposed within the body and movable to selectively drain the control chamber, thereby causing the needle element to move between the first and second positions. The fuel injector may further have an armature disposed within an armature cavity of the body and selectively energized to move the control valve, and a pressure reducer disposed within the body and configured to reduce a pressure of the armature cavity.

Abstract: A valve assembly for an injection valve may include a valve body comprising a cavity with a fluid inlet portion and a fluid outlet, and a valve needle axially movable in the cavity, the valve needle preventing a fluid flow through the fluid outlet in a closing position and releasing the fluid flow through the fluid outlet in further positions, the valve needle comprising a radially extending protrusion and an electro-magnetic actuator unit configured to actuate the valve needle and comprising an armature in the cavity. The armature comprises an armature cavity having a first stop surface and a second stop surface that faces the first stop surface. The protrusion of the valve needle is arranged in the armature cavity axially between the first stop surface and the second stop surface such that a relative movement between the valve needle and the armature in axial direction is limited.

Abstract: A mechanically actuated electronically controlled unit injector includes an electronically controlled spill valve to precisely control timing of fuel pressurization within a fuel pressurization chamber. Cavitation bubbles may be generated in the region of the valve seat when the spill valve member is closed to raise fuel pressure in the fuel injector. This cavitation can cause erosion on the spill valve member and the surrounding injector body. In order to preempt cavitation damage, the valve member may be modified to include a compound annulus that includes a small annulus that corresponds to an identified cavitation damage pattern. Although the generation of cavitation bubbles may continue after such a strategy, cavitation erosion, and the associated liberation of metallic particles into the fuel system can be reduced, and maybe eliminated, by the preemptive cavitation reduction strategy.

Abstract: A valve unit is disclosed for the interruption or release of a pressurized flow of a medium along a hollow duct, which flows along the hollow duct, as well as a preferred use of the valve unit in a dosing system and a method for the metered discharge of a medium from a cartridge-needle configuration, with a cartridge connected to the needle configuration via at least one hollow duct with an open cartridge end, to which a pressurizing means is applied, which is capable of driving the medium provided inside the cartridge in the direction of the needle configuration for discharge by applying pressure.

Abstract: Disclosed is a fuel injector in which at least one electrically triggered valve is disposed inside an injector member and is connected to an externally accessible injector member contact by means of a solid conductor, the solid conductor and the electrical valve contact being interconnected directly via an electrically conducting positive connection or indirectly via an electrically conducting connecting element. The solid conductor is configured so as to substantially maintain the shape thereof under the influence of the proper weight thereof.

Abstract: A fuel injector, in particular for direct injection of fuel into a combustion chamber of an internal combustion engine, has a valve needle, which is situated in a nozzle body and is operable by an actuator, and a valve closing body, which is operatively connected to the valve needle and, for opening and closing the valve, cooperates with a valve seat face formed on a valve seat body, the valve seat body being provided with at least one spray hole. The at least one spray hole has a first cylindrical section having a fuel inlet opening and a second cylindrical section situated downstream from the first cylindrical section and having a fuel outlet opening, the first and the second cylindrical sections not running coaxially to one another.

Abstract: An electromagnetically operatable valve, in particular a fuel injector for fuel injection systems of internal combustion engines, includes a magnetic circuit having a core, a solenoid, an armature, which operates a valve closing body cooperating with a fixed valve seat and is drawn against the core when the solenoid is excited, and is held on the valve closing body by a closing body carrier representing a part of a valve needle. The spherical valve closing body is secured on the closing body carrier in a non-positive manner due to the shape of the corresponding connecting surfaces. The valve is suitable in particular for use in fuel injection systems of mixture-compressing, externally ignited internal combustion engines.

Abstract: A fuel injector apparatus and method for use in a fuel injection system of an internal combustion engine that includes a body, a valve seat, closure member, and an orifice plate. The valve seat comprises the intersection of two angled surfaces before assembly of the fuel injector. During assembly of the fuel injector, a member presses against the edge of the sealing surface of the valve seat to create an oblique third sealing surface or sealing band that is coined into the valve seat. The sealing band provides an improved seal between the valve closure member and the valve seat which operates to prevent leakages of fuel in the fuel injector.

Abstract: In a fuel injection valve having a valve plug for opening and closing a valve seat in which fuel is injected from a plurality of orifices provided in an orifice plate mounted at the downstream side of the valve seat by operating the valve plug in response to an operation signal from a controller, a thin wall part is provided by concaving a center portion of an upstream-side end face of the orifice plate to the downstream side by press working, and the orifice plate is disposed so that a virtual circular conical surface extending to the downstream side of the valve seat surface and an upstream-side end face of the orifice plate of the outer peripheral side of the thin wall part intersect to each other to form one virtual circle.

Abstract: A thermal fuse integrated into an electrical circuit powering a heater element having a positive temperature coefficient includes at least one terminal in electrical connection with the heater element thereby connecting the heater element to a power source, and a solder jacket that mechanically retains the electrical connection between the terminal and heater element, wherein a biasing load is applied to the terminal when retained by the solder jacket, and wherein the terminal breaks connection with the heater element under the force of the bias when the solder jacket melts should the heater element overheat. By selecting the solder material forming the solder jacket according to its melt temperature, a temperature specific overheat protection for a heated fuel injector can be provided. Since the injector's metering circuit is separate from the thermal fuse circuit, the fuel injector remains operational even after the heater circuit is opened.

Abstract: A fuel injection valve has a valve body for opening and closing a valve seat, and receives an operation signal from a control unit to operate the valve body so that fuel is injected from a plurality of injection holes formed in an injection hole plate welded through a welded portion to a downstream side of the valve seat while passing through a gap between the valve body and the valve seat. The injection hole plate is formed at its central portion with a convex portion which is substantially axisymmetric with respect to a valve seat axis and which has a circular-arc shaped cross section, and the welded portion is also substantially axisymmetric with respect to the valve seat axis.

Abstract: A short travel solenoid actuator (44) is disclosed which comprises at least one pole piece (47, 48), an armature (51), an electromagnet coil (46) arranged, in response to energisation, to actuate the armature between first and second positions. A permanent magnet (52) is positioned and orientated so as to latch the armature in the first and second positions when the armature is in the first and second positions respectively. A spring (53) is arranged to bias the armature.

Abstract: Electromagnetic fuel injector for gaseous fuels comprising: an injection nozzle controlled by an injection valve; a movable shutter to regulate the flow of fuel through the injection valve; an electromagnetic actuator, which is suitable to move the shutter between a closed position and an open position of the injection valve and comprises a fixed magnetic pole, a coil suitable to induce a magnetic flux in the magnetic pole, and a movable anchor suitable to be magnetically attracted by the magnetic pole; an absorption element, which is made of an amagnetic elastic material and is arranged between the magnetic pole and the anchor; and a protective element, which is made of a magnetic metal material having high surface hardness and is interposed between the absorption element and the anchor.

Abstract: A nozzle assembly includes a first needle and a second needle controlling respectively fuel flow towards a first series of outlets and a second series of outlets. It includes a passive control valve adapted to select, on the basis of the fuel feeding pressure, the needle to be activated for fuel delivery to the combustion chamber of an internal combustion engine. An injector with such an assembly is economic and efficient to spray fuel with two different patterns.

Abstract: A fuel injector (10) has a housing (12) with a central longitudinal axis (L) having a fluid inlet portion (18) being adapted to be coupled to a fuel rail at a first axial end area (20). The housing (12) has a recess (24) and enables a fluid flow through a fluid outlet portion (26) at a second axial end area (28) facing away from the first axial end area (20). The fluid inlet portion (18) communicates with the fluid outlet portion (26) via the recess (24). Furthermore, the fuel injector (10) has a safety component (30), which is arranged at the central longitudinal axis (L) within the recess (24) and adapted to reduce and arranged for reducing a velocity regarding the central longitudinal axis (L) at the fluid inlet portion (18) of the fluid flowing from the recess (24) through the fluid inlet portion (18).

Abstract: A fuel injection valve includes a valve element movably disposed to a valve seat member having a valve seat and formed with an opening located at a downstream side thereof. A swirl imparting chamber is formed to impart a swirl force to fuel within the swirl imparting chamber by turning fuel. An injection hole is opened to the bottom of swirl imparting chamber to inject fuel to outside. Additionally, a communication passage is formed to connect the swirl imparting chamber with the opening of the valve seat member. In this fuel injection valve, the swirl imparting chamber and the communication passage are formed to satisfy the following equation: 0.15?W/D<0.5 where W is width of the communication passage; and D is diameter of the swirl imparting chamber.

Abstract: A fuel injector for fuel injection systems of internal combustion engines is described. The fuel injector includes an electromagnetic actuating element having a magnetic coil, a core and a valve jacket as the outer magnetic circuit component and a movable valve-closure member which interacts with a valve-seat surface assigned to a valve-seat member. The core and a connecting tube in an inner opening of a thin-walled valve sleeve and the valve jacket on the outer circumference of the valve sleeve are firmly connected to the valve sleeve by pressing them therein/thereon. The fixed press connection between two of these metallic components of the fuel injector is characterized in that at least one of the component partners has a structure including grooves in its press area and/or the particular press area has an inlet rounding in at least one transition to an adjacent component section.

Abstract: A nozzle module for an injection valve has a nozzle body with a nozzle body opening extending in the direction of a longitudinal axis, and which can be hydraulically coupled to a fluid feed; a nozzle needle which is movable axially in the nozzle body opening and which in a closed position prevents a flow of fluid through at least one injection opening and otherwise releases the fluid flow; and an induction-heated heating element disposed between the nozzle body and the nozzle needle. The heating element is at least partially spaced a distance away from the nozzle body and from the nozzle needle, and during operation of the injection valve the fluid can flow against a side of the heating element facing the nozzle body and a side of the heating element facing the nozzle needle.

Abstract: Use of carbon nanotubes (CNTs) in a charge injector to assist in atomizing fuel for engine applications. A CNT charging unit is positioned in front of a fuel injector. A voltage is applied on a CNT coated mesh to charge the fuel stream when it passes. Then the charged stream goes through a grounded metal cage. The fuel is thereby electrostatically charged causing repulsive forces on surfaces of liquid in the fuel resulting in the liquid splitting into droplets.

Abstract: A method of combustion stability control for a gas turbine engine is provided, and includes the steps of receiving by a stability controller, information regarding environmental and operating conditions, and comparing the environmental and operating conditions to pre-programmed information to determine if a likelihood of combustion instability exists. The method further includes the steps of determining optimal fuel modulation frequency and amplitude for the environmental condition to reduce combustion instability, if a likelihood of combustion instability exists, and actuating at least one fuel modulation valve to, at the optimal fuel modulation frequency and amplitude, reduce combustion instability, if a likelihood of combustion instability exists. Systems for modulating fuel flow are also provided.

Abstract: The invention relates to a fuel injector with an injector housing which has a high-pressure fuel connection which is connected to a central high-pressure fuel source outside the injector housing, and with a pressure chamber within the injector housing. According to the pressure in a coupling chamber, fuel under a high pressure is injected from the pressure chamber into a combustion chamber of an internal combustion engine when a nozzle valve opens. The nozzle valve has a combustion chamber-remote end with a control pressure surface which is acted upon in the coupling chamber by the coupling chamber pressure. In order to create a fuel injector which can be produced inexpensively, the nozzle valve has at least one low-pressure surface which is averted from the combustion chamber and acted upon with low pressure.

Abstract: An injector includes a control valve for opening a connection between a control chamber for controlling a nozzle needle position and a prechamber of a fluid return line, wherein a pressure compensation device is arranged in the prechamber for compensating a change in a prechamber pressure.

Abstract: The invention relates to a magnetic assembly (10) of a solenoid valve, particularly for actuating a fuel injector, having a housing (12, 16) receiving a magnetic core (28) having a magnetic coil (26). Electrical contacts (32) are led through penetrations (34) out of the housing (12, 16). The electrical contacts (32) in the housing (12, 16) for supplying the magnetic coil (26) with current are attached by means of an adhesive connection (50).

Abstract: A fuel injector for an internal combustion engine is provided which has a fuel supply path and a nozzle chamber. The fuel supply path extends a spray hole. The nozzle chamber is defined in the fuel supply path. A nozzle is disposed within the nozzle chamber to establish or block a fluid communication between the fuel supply path and the spray hole. A fuel pressure sensor is installed in the fuel injector so as to be exposed to the fuel in the nozzle chamber. Specifically, the fuel pressure sensor is located closer to the spray hole than a prior art structure in which the fuel pressure sensor is installed in a fuel supply pipe, thus resulting in increased accuracy in measuring a change in pressure of the fuel arising from the spraying of the fuel from the spray hole.

Abstract: A direct fuel injector (10) includes a body (12) having a passage between inlet and outlet ends. A seat (16) is at the outlet end and a closure member (28) is associated with the seat. A needle member (30) is associated with the closure member and is movable with respect to a pole piece (35) between a first, closed position and a second, open position. A spring (42) biases the needle member to the first position. An armature (32) is free-floating with respect to the needle member. An intermediate pole structure (38) is coupled with the needle member and is disposed between the pole piece and the armature and is decoupled there-from. An armature stop (40) is coupled to the needle member and is spaced from the intermediate pole structure. An electromagnetic coil (46) is associated with the pole piece, intermediate pole structure and armature. The injector reduces bounce of the needle assembly.

Abstract: In an electromagnetic fuel injection valve, a valve body guide hole (15) which is connected to a valve seat (8) of a valve seat member (3) and slidably guides a valve body (14), and a large-diameter hole (17) which is connected to a rear end of the valve body guide hole (15) via a tapered hole (16) and has a diameter larger than that of the valve body guide hole (15), are provided in the valve seat member (3) of a valve housing (2), whereas a first longitudinal hole (19) which communicates with a fuel intake cylinder (26) is provided in a fixed core (5); a second longitudinal hole (20) which communicates with the first longitudinal hole (19) is provided from a movable core (12) to a valve shaft (13); a traverse hole (21) which opens the second longitudinal hole (20) to the large-diameter hole (17) is provided in the valve shaft (13); and a relationship between the diameter (D1) of the large-diameter hole (17) and the diameter (D2) of the valve body guide hole (15) satisfies D2/D1<0.6.

Abstract: There is provided a micro-ejecting apparatus. The micro-ejecting apparatus includes: an ejector including a channel therein and a driving part for ejecting a fluid to the outside; a body including a plurality of mounting parts on which the ejector is mounted; and guiding members fixed on the body and corresponding to the plurality of mounting parts so as to determine the positions of the plurality of mounting parts in the body.

Abstract: A method of operating a pressure compensated fuel injector includes: filling a fuel chamber with a charge of fuel by closing an injector valve and circulating a fuel from a fuel source through a plurality of recirculating valves and a cap valve; then isolating the fuel chamber and the charge of fuel from the fuel source; then equalizing a pressure within the fuel chamber to a rising pressure outside the fuel chamber by reducing a volume of the isolated fuel chamber; and then activating a solenoid that is coupled to the injector valve, opening the injector valve; and then further reducing the volume of the isolated fuel chamber to apply an over pressure within the chamber, pumping fuel from the fuel chamber through the injection orifice.

Abstract: A fluid injector has a valve body with a recess in which a valve needle is arranged axially movable preventing a fluid flow and being mechanically coupled to an axial end of a first spring preloaded to exert a force on the valve needle. A first armature is mechanically coupled to the valve needle. A second armature is arranged in the recess axially movable away and towards a protrusion of the valve body mechanically coupled to an axial end of a second spring preloaded exerting a force on the second armature which is arranged and designed such that from a closing to a first given position, the first and second armature are mechanically decoupled, and from the first given position further away from the closing position, the first and second armature are mechanically coupled. A solenoid drive magnetically actuates the first and second armature to move axially.

Abstract: An actuator arrangement for an electromagnetically operated fuel injector, includes a generally cylindrical actuator core having a longitudinal axis and defining an inner pole face of the actuator arrangement. The actuator core is formed of a bespoke magnetic material. A wire coil is disposed around the actuator core arranged to be connected to a power source to generate a magnetic field around the coil. A pole member is formed of a high strength material and defines an aperture for receiving the actuator core. The pole member defines an outer pole face of the actuator arrangement substantially co-planar with the inner pole face. An armature is movable in a direction parallel to the longitudinal axis in response to the magnetic field. The magnetic field passes into the armature in the region of the inner pole face and into the armature in the region of the outer pole face.

Abstract: With reference to FIG. 3, the present invention provides a fluid injector (10) which functions as a positive displacement pump and comprises: a housing (12) in which a piston chamber is formed; a piston (11) which reciprocates in the piston chamber to define therewith a variable volume fluid pumping chamber; a one-way inlet valve (32) which allows flow of fluid into the pumping chamber from a fluid inlet; and a one-way outlet valve (25, 26, 27, 28, 29) which allows flow of fluid out of the pumping chamber to a fluid outlet (31). In operation of the injector the piston (11) cyclically moves to increase volume of the pumping chamber and draw fluid into the pumping chamber via the one-way inlet valve (32) and then the piston moves to decrease volume of the pumping chamber and expel fluid from the pumping chamber via the one-way outlet valve (25, 26, 27, 28, 29).

Abstract: A device is described for injecting fuel, which includes a valve body, an outwardly opening valve needle, which is disposed in the valve body in a pressure chamber filled with fuel, to which pressurized fuel is supplied; a restoring element, which returns the valve needle to an original position; an electromagnetic actuator, which is disposed in an actuator chamber for actuating the valve needle; and a diaphragm, which is disposed in the actuator chamber and subdivides the actuator chamber into a first, fuel-filled region and a second, fuel-free region in fluid-tight manner, and which subdivides the valve needle into an injection-side portion and an actuator-side portion, the injection-side portion of the valve needle including a pressure-compensation plunger, which separates the pressure chamber from the first, fuel-filled region of the actuator chamber, the actuator being disposed in the second, fuel-free region.

Abstract: A solenoid actuator includes a hard guide piece and a soft flux piece. The hard guide piece has a stop surface ground to create a final air gap distance between the soft flux piece and a stator assembly when the stop surface on the guide piece is in contact with the stator assembly. The final air gap is set by grinding the stop surface on the guide piece so that the distance between the stop surface on the guide piece and a top surface on the soft flux piece along an axis of the guide bore is equal to the final air gap. The step of grinding the armature assembly may be done after attaching the guide piece and the flux piece together. In an exemplary embodiment, the step of grinding the stop surface and associated guide surface(s) are performed in a single chucking.

Abstract: Disclosed is a fuel injection device comprising a housing and a valve element disposed therein and cooperating with a valve seat located in the area of at least one fuel discharge port. The valve element is composed of several parts while at least two parts of the valve element are coupled to each other via a hydraulic coupler.

Abstract: The objective of the present invention is to realize the structure, of a fuel injection valve, in which bouncing of the needle can be suppressed and the armature position can be fixed while the valve is closed, without increasing the number of components and the number of processes. In a fuel injection valve including an armature that is repelled or attracted by a core, by de-energizing or energizing a coil; a needle that opens or closes a valve seat in accordance with a reciprocal travel of the armature; and a valve-closing spring that biases the needle so as to close the valve, when the coil is de-energized, the needle and the armature are fixed in such a way that the armature can travel in an axis direction by a predetermined amount with respect to the needle, and the coil is preliminarily energized while the fuel injection valve is closed by the needle.

Abstract: The invention relates to a fuel injector comprising an injector housing having a pressure chamber from which fuel subjected to a high pressure is injected into a combustion chamber of an internal combustion engine when the pressure in a control chamber expands into a pressure relief chamber by a control valve device. The aim of the invention is to create a fuel injector which has a long service life even though subjected to high pressures. To this end, the injector includes a low-pressure supply line which is connected to a low-pressure return line by a purge path extending through the pressure relief chamber.

Abstract: In order to operate an injection valve, a freewheeling operating state is controlled as the nozzle needle moves to its closing position, and a current through the coil is detected as a freewheeling current during freewheeling. As the nozzle needle moves to its closing position, a braking current pulse (I_BR) is generated on the basis of a time derivative (DI_DT_FW) of the freewheeling current and is impressed on the coil.

Abstract: In relation to injectors used for internal-combustion engines, it is important to decrease valve closing delay time and also the minimum injection quantity, while these are affected by remanent magnetism in the fixed core, surface tension of the fuel, etc. With reference to a fuel injection valve with a pipe-shaped member to enclose a fixed core and a movable part and further with coils and yokes to cover up the above pipe-shaped member, the anchor to drive the movable member has a plurality of through holes for fuel passage extending in the axial direction, while these through holes are arranged at a certain intervals in the circumferential direction, and projections formed to constitute a contacting surface to touch the fixed core arranged randomly in between the through holes.

Abstract: An injector includes a valve body, a needle valve, and a thermal expansion member. The valve body includes an internal space and a bottom portion having a nozzle hole. One end side of the space is covered with the bottom portion. The needle valve is accommodated in the space such that a fuel passage leading to the hole is formed between an inner surface of the valve body and an outer surface of the needle valve. The passage is opened or closed with respect to the hole by movement of the needle valve, so fuel injection is started or stopped. The inner surface of the bottom portion is opposed to a one end surface of the needle valve. The member is attached on the one end surface. The member is made of a material having a larger coefficient of thermal expansion than a material of the needle valve.