Abstract: A fuel injection valve, particularly an injection valve for fuel injection equipment of internal combustion engines, having a pump piston that can be activated using a piezoelectric or magnetostrictive actuator for exerting a translatory pump motion. A spray-discharge nozzle with at least one spray-discharge opening is hydraulically connected via a fuel pressure line to the pump piston. The spray-discharge nozzle opens when the fuel pressure produced by the pump piston in the fuel pressure line exceeds a predetermined threshold. In the fuel pressure line, at least one non-return valve is arranged so that it opens in the direction towards the spray-discharge nozzle and closes in the opposite direction.

Abstract: The fuel injection device of this invention utilizes the fuel pressure in the balance chamber for closing the open-close valve to prevent fuel leakage from the open-close portion. When the open-close valve is opened, the valve stem of the open-close valve piercing through the exhaust passage in the control member moves toward the balance chamber. The valve head opens the port of the exhaust passage on the balance chamber side to lower the fuel pressure in the balance chamber, with the result that the needle valve lifts injecting the fuel. When the open-close valve is closed by the return spring, the fuel pressure in the balance chamber acts on the valve head to urge the open-close valve in the valve closing direction, preventing the leakage of fuel through the open-close valve.

Abstract: A valve assembly includes a first body with a first conical valve seat and a locating bore centered about a first axis. A second body is press fit attached to the first body and has a second conical valve seat with a second axis positioned in opposition to the first conical valve seat. An elongated valve member with a centerline has an upper conical valve surface and a lower conical valve surface trapped between the first conical valve seat and the second conical valve seat. A guide portion of the elongated valve member moves in a guide bore defined by one of the first body and the second body. The first axis, the second axis and the centerline are concentrically linked via the press fit attachment of the second body in the locating bore of the first body. The valve assembly is preferably utilized as a needle control valve assembly in a fuel injector.

Abstract: An actuation fluid control valve for a hydraulically actuated fuel injector comprises an injector body having an actuation fluid control passage, a low pressure actuation fluid drain passage, and a high pressure actuation fluid supply passage for accepting high pressure actuation fluid into the fuel injector. An actuator is attached to the injector body. A rotatable valve member includes a first valve passage and a second valve passage and is disposed in the injector body such that high pressure actuation fluid entering from the high pressure actuation fluid supply passage will not bias the rotatable valve member either toward the first position or toward the second position.

Abstract: An actuation fluid control valve for a hydraulically actuated fuel injector comprises an injector body having a high pressure actuation fluid supply passage for admitting high pressure hydraulic actuation fluid into the fuel injector, an actuation fluid control passage for admitting the high-pressure hydraulic actuation fluid to commence fuel injection, a low-pressure actuation fluid drain passage for draining the hydraulic actuation fluid from the fuel injector, and a check valve fluid control passage for admitting the high pressure hydraulic actuation fluid to terminate fuel injection. An actuator is attached to the injector body. A rotatable valve member includes a first valve passage and a second valve passage and is disposed in the injector body such that high pressure actuation fluid entering from the high pressure actuation fluid supply passage will not bias the rotatable valve member either toward the first position or toward the second position.

Abstract: A hydraulically-actuated fuel injector includes an injector body that defines an upper actuation fluid cavity, a lower actuation fluid cavity, an actuation fluid inlet, a spill passage, a piston bore and a nozzle outlet. A control valve member is positioned in the injector body and moveable between a first position and a second position. An intensifier piston is positioned in the piston bore and moveable between a retracted position and an advanced position. The piston has a primary hydraulic surface exposed to fluid in the upper actuation fluid cavity, and an opposing hydraulic surface exposed to fluid in the lower actuation fluid cavity. The upper actuation fluid cavity is open to the actuation fluid inlet, and the lower actuation fluid cavity is open to the spill passage when the control valve member is in its first position. The spill passage is blocked when the control valve member is in its second position.

Abstract: An improved unit fuel injector is provided which effectively and precisely controls the timing of fuel injection by avoiding outside influences acting on a timing plunger. The unit fuel injector includes a timing plunger positioned between upper and lower plungers, a timing chamber positioned between the timing plunger and upper plunger and a spring chamber positioned between the timing plunger and a metering chamber for containing one or more springs for biasing the plungers. A spring chamber drain valve device is provided for directing fuel in the spring chamber to a low pressure drain while isolating the spring chamber from the low pressure drain system thereby preventing pressure variations in the drain system from entering the spring chamber and acting on the timing plunger. In addition, a scavenge circuit is provided to direct a scavenging flow of fuel and combustion gas from the injector directly to the low pressure drain without communication with the spring chamber.

Abstract: An accumulator fuel injection apparatus for an internal combustion engine is provided which includes a solenoid-operated fuel injector. The fuel injector includes a solenoid valve and a needle valve. The solenoid valve establishes and blocks fluid communication between a pressure control chamber supplied with fuel pressure from a fuel inlet and a drain passage formed in a valve body to change fuel pressure within the pressure control chamber, thereby bringing the needle valve into engagement with and disengagement from a spray hole. The fuel injector also has a first orifice disc and a second orifice disc installed within the valve body. The first orifice disc has formed therein a first orifice which provides a first flow resistance to fuel flowing from the fuel inlet into the pressure control chamber.

Abstract: A fuel injector includes an injector body that defines a nozzle outlet, and a needle control chamber that is in fluid communication with a needle control passage. A needle valve member is positioned in the injector body, and has a closing hydraulic surface exposed to fluid pressure in the needle control chamber. The needle valve member is moveable between a first position in which the nozzle outlet is blocked, and a second position in which the nozzle outlet is open. The needle control passage includes a dual flow rate orifice. Hydraulic fluid is displaced into the needle control chamber through the dual flow rate orifice when the needle valve member moves from its second position toward its first position. Hydraulic fluid is displaced out of the needle control chamber through the dual flow rate orifice when the needle valve member moves from its first position toward its second position. A compression spring is operably positioned to bias the needle valve member toward its first position.

Abstract: A cartridge control valve includes a valve body that defines an inlet passage separated from an outlet passage by a flat valve seat. A solenoid is attached to the valve body. A valve member has one end positioned in the valve body and an other end attached to the solenoid. The valve member has an annular knife edge valve surface located between the one end and the other end. The valve member is moveable from a first position to a second position by energizing the solenoid. The annular knife edge surface is away from the flat valve seat to open the inlet passage to the outlet passage when the valve member is in one of its first position and its second position. The annular knife edge valve surface is seated against the flat valve seat to close the inlet passage to the outlet passage when the valve member is in the other of its first position and its second position.

Abstract: A fuel injector that contains no springs and is controlled by a valve assembly that has more than two modes of operation. The fuel injector includes a housing which has a supply port, a drain port and a cylinder passage that is in fluid communication with an intensifier. The intensifier moves between a first position and a second position within a fuel chamber. The fuel chamber is coupled to a fuel port. Movement of the intensifier into the second position pressurizes the fuel within the fuel chamber. The pressurized fuel opens a needle valve so that fuel is ejected through an aperture of the housing. The cylinder passage is coupled to a first fluid control valve and a second fluid control valve. Each control valve can be actuated between a closed position and an open position.

Abstract: A diesel unit injector of the END type is provided with a sac whose center of volume is located below the center of radius of the sac bottom. The bottom-most parts of the annular cavity which is above the seat for the nozzle valve are shaped to provide compensatory structural reinforcement.

Abstract: A fuel injector adapted for an internal combustion engine has a cam driven pumping mechanism, a pressure intensifier mechanism, an injection mechanism, and an electronically responsive relief valve mechanism. The cam driven pumping mechanism has a pumping piston operably reciprocating to pressurize a hydraulic fluid to a first pressure. The pressure intensifier mechanism receives the hydraulic fluid at the first pressure from the pumping mechanism, and acts against fuel to pressurize it to a second pressure greater than the first pressure. The injection mechanism receives the highly pressurized fuel from the intensifier mechanism. The injection mechanism includes a check blocking an orifice in an end portion of the injection mechanism. The pressurized fluid displaces the check away from the end of the injection mechanism by the pressurized second fluid to begin fuel injection.

Abstract: A fuel injector includes a tip member having a further member establishing an interference fit about an outer surface thereof at an injection end to minimize the possibility of fracture or other failure.

Abstract: In a fuel injection system for a multi-cylinder internal combustion engine with magnetic valve controlled direct injection fuel injectors of which each comprises a housing consisting of several parts, one part having an injection nozzle with a spring loaded nozzle needle and another part including a control piston with a valve structure having an integral valve seat for controlling high pressure fuel admission to a fuel supply passage extending through the housing to the injection nozzle, a control chamber is formed at the other end of the control piston and is in communication with the high pressure fuel supply, and a magnetic valve arranged adjacent the control chamber controls communication of the control chamber with a drain line for releasing pressurized fuel from the control chamber to permit unseating of the control piston so as to establish communication between the pressurized fuel supply and the injection nozzle past a lug extending from the control piston into a fuel admission bore.

Abstract: A fuel injection valve for an internal combustion engine includes a valve block; an injection nozzle carried by the valve block and having a nozzle opening; a valve needle slidable in the injection nozzle for assuming closed and open positions to block and, respectively, to unblock the nozzle opening; a closing spring urging the valve needle into the closed position; and a pressurized fluid port in the valve block. The nozzle opening is in communication with the pressurized fluid port in the open position of the valve needle. A discharge port is defined in the valve block for carrying fluid away therefrom. An equalizing piston, which is slidably disposed in a work chamber in the valve block, is connected with the valve needle. A control plunger is movable in the valve block and has a first position and a second position.

Abstract: A fuel injector for effectively preventing excessive loading of a component mounted internal to the injector is provided which includes a one-piece retainer having first and second connector portions for permitting two independent loads to be applied to different internal components of the injector. The second connector portion includes threads for engaging a nozzle assembly to impart a compressive force on the nozzle assembly. The first connector portion also includes threads for engaging an outer barrel for placing a first compressive load on a load sensitive internal component, such as a center tube of an injection control valve. In this manner, the second compressive force can be set at a minimum level independent from the first compressive force to permit the size of the center tube to be minimized thereby reducing the overall size of the injector.

Abstract: A fuel injection device for internal combustion engines in which a fuel injection valve has a tappet which is actuated by an injection valve member and defines a control chamber that is supplied continuously with high fuel pressure via a throttle and can be relieved via a control valve and an outflow conduit. To that end, the control valve has a valve member, which is actuated by a piezoelectric element in such a way that the valve member is moved toward the control chamber when the outflow conduit opens. In the closing position, the valve member is urged in the closing direction by the pressure in the control chamber.

Abstract: A fuel injector includes a center tube which conducts fuel flow. A flat-seat poppet valve surrounds a lower portion of the center tube and controls the application of pressurized fuel to first and second check end passages to assist in check closure.

Abstract: A control valve, preferably for use in a fuel injector, includes a valve body that defines a first passage and a second passage. A solenoid is attached to the valve body and has an armature. A multi piece valve member is attached to the armature and is positioned in the valve body. The multi piece valve member is moveable between a first position in which the first passage is open to the second passage, and a second position in which the first passage is closed to the second passage. The multi piece valve member includes a second valve member piece moveable with respect to a first valve member piece between a contact position in which a portion of the second valve member piece is in contact with the first valve member piece, and a separated position in which the portion is a distance away from the first valve member piece. A damping spring is compressed between the second valve member piece and the first valve member piece when the second valve member piece is in its separated position.

Abstract: A hydraulically-actuated fuel injector includes an injector body that defines a high pressure inlet, a low pressure drain, an upper actuation fluid cavity, a lower actuation fluid cavity, and a nozzle outlet. A piston is positioned in the injector body and moveable between a retracted position and an advanced position. A control valve is attached in the injector body and includes a spool valve member that is moveable between a first position and a second position. When the spool valve member is in its first position, the piston is biased toward its retracted position since the upper actuation fluid cavity is open to the low pressure drain, but the lower actuation fluid cavity is open to the high pressure inlet. During an injection event, the spool valve member is moved to its second position where the upper actuation fluid cavity is open to the high pressure inlet, but the lower actuation fluid cavity is open to the low pressure drain.

Abstract: A control valve, preferably for use in a fuel injector, includes a valve body defining an inlet passage separated from an outlet passage by a valve seat. A single pole solenoid is attached to the valve body, and includes a pole piece and an armature. A valve member with a centerline is positioned in the valve body, attached to the armature and moveable between an open position in which the inlet passage is open to the outlet passage, and a closed position in which the inlet passage is closed to the outlet passage. The pole piece is positioned between the valve seat and the armature along the centerline of the valve member.

Abstract: A fuel injection nozzle includes a lift piece located on the side of a nozzle needle. A protrusion of the lift piece and the distal end of a push rod are held by a spring seat with a specified clearance therebetween as a prelift. The adjustment of the prelift can be performed only by taking out the lift piece to be adjusted, so that the adjusting work of the prelift, accompanied with disassembly of the fuel injection nozzle becomes easy and fuel injection characteristics are improved.

Abstract: A fuel injector includes a center tube, a first valve separate from the center tube and surrounding a first end of the center tube and a second valve also separate from the center tube and surrounding a second end thereof. A solenoid is actuable to independently move the first and second valves and thereby control the application of fluid pressures to first and second ends of a check assembly, in turn to control injection of fuel into an associated engine cylinder.

Abstract: An injector is described which comprises a valve needle engageable with a seating and biased towards the seating by a spring. The spring is located within a spring chamber and engages a moveable stop. The spring chamber communicates through a restricted passage with a low pressure drain. The injector further includes valve means which, when open, permits fuel to escape from the spring chamber at a higher rate.

Abstract: A fuel injector includes a valve member disposed at the upper end of the injector case adjacent a valve recess. The valve member includes a bore and a counterbore, and a tube having a bore is slidably disposed within the counterbore. The valve member bore and the tube bore define a fuel flow passage substantially coincident with the central axis of the injector. The valve member is spring biased to an open position to communicate fuel at transfer pump pressure to the valve recess. At the initiation of the injection cycle, an actuator, preferably an electrical solenoid, closes the valve against the spring force so that fuel is communicated along the central passage to a nozzle.

Abstract: A control valve includes a terminal assembly that has a terminal electrically connected to one of a male electrical connector and female electrical connector. A solenoid assembly includes a metallic solenoid housing defining a solenoid cavity. A solenoid coil and the other of the male electrical connector and the female electrical connector are molded into a plastic solenoid carrier. The plastic solenoid carrier is attached to the metallic solenoid housing and preferably molded into the solenoid cavity. The solenoid assembly is attached to the terminal assembly, and said male electrical connector is mated to the female electrical connector. An armature is positioned between a portion of the terminal assembly and the solenoid coil. A valve member is attached to the armature.

Abstract: The present solenoid stator assembly is adapted to be mounted upon a mounting seat of a fuel injector valve. The assembly includes a housing having an upper end, a lower end, and a base adapted to fit on the mounting seat of the fuel injector valve. A substantially E-shaped stator core is disposed within the housing. The stator core includes a top portion having a first end and a second end. A first outer pole piece depends substantially perpendicularly from the first end, and a second outer pole piece depends substantially perpendicularly from the second end. The central pole piece is located substantially central to the first and second outer pole pieces, and depends substantially perpendicularly from the top portion in a direction substantially parallel to that of the first and second outer pole pieces. The first and second outer pole pieces and the central pole piece each have a distal end forming a face, each face being substantially flush with the base of the housing.

Abstract: An injector arrangement is disclosed which comprises a valve needle urged into engagement with a seating under the action of the pressure of fuel within a control chamber. A needle control valve controls communication between a source of fuel at high pressure and the control chamber, and also between the control chamber and a low pressure drain. The needle control valve includes a valve member including an end which is engageable with a surface extending in a plane normal to the axis of the valve member to close a port communicating with the low pressure drain.

Abstract: A wear and scuff-resistant timing plunger for a timing assembly in a unit fuel injector for an internal combustion engine is provided. The timing plunger is formed of a high thermal expansion ceramic with a thermal expansion coefficient greater than 6.times.10.sup.-6 /.degree. C. and a hardness greater than 800 Kg/mm.sup.2, which maintains a desired diametral clearance and efficient plunger function without scuffing or sticking under the axial, tangential and pressure loads encountered in the fuel injector operating environment. Preferred high thermal expansion ceramics are zirconia, alumina-zirconia and alumina.

Abstract: A fuel injector assembly is provided which operates to effectively creating a low injection flow rate followed by a high injection flow rate during all engine operating conditions, including idle and low engine speed conditions, to produce a high quality fuel spray with proper atomization and thus improved fuel air mixing resulting in improved emissions abatement and fuel economy. The assembly includes two biased valve elements designed to sequentially open and close to initially open a limited number of orifices followed by the opening of a remainder of the orifices thereby effectively varying the available cross sectional flow area from the nozzle cavity into the combustion chamber of the engine during the injection event. The nozzle valve elements may be spring biased or fluid pressure biased and include biasing surfaces sized to cause the sequential opening and closing of the elements.

Abstract: A control valve includes a first valve body component that defines an outlet passage and a first planar surface surrounding a valve seat. A second valve body component has a second planar surface and is fastened against the first valve body component with the second planar surface in contact with the first planar surface at a sealing land. The first valve body component and the second valve body component define a high pressure cavity surrounded by the sealing land. One of the first valve body component and the second valve body component define an inlet passage opening to the high pressure cavity. A valve member has a portion positioned in the high pressure cavity and is moveable between a closed position in which the valve member contacts the valve seat closing the outlet passage to the high pressure cavity, and an open position in which the outlet passage is open to the high pressure cavity. The sealing land has a symmetrical non-circular shape.

Abstract: An improved cam operated, open nozzle, unit injector is disclosed including an injector body formed by a barrel, spring housing, and nozzle and containing a central bore for receiving a variable length plunger assembly mounted for reciprocal movement within the injector body wherein the variable length plunger is formed by an outer plunger and inner plunger combined with a timing plunger, mounted between the inner and outer plungers to form a collapsible timing chamber into which a variable quantity of fuel may be metered and expelled on a cycle by cycle basis to provide a variable effective length to the plunger assembly to cause controlled variation in injection timing based on variation in the timing fluid supplied to the injector and wherein the timing plunger is provided with a radial flange for engaging a stop formed in the injector barrel to hold the timing plunger in a predetermined precise location during metering of timing fluid into the collapsible timing chamber and to render the injector timing i

Abstract: A fuel injector comprises a barrel, a plunger, and a port. The plunger is disposed in a bore in the barrel such that it intersects the port disposed in the barrel. The plunger has an injection rate shaping device and a cavitation control device disposed therein. The pressure control device is in such a position on the plunger such that subsequent to the rate shaping device passing fluidly communicating with the port, the cavitation control device aligns with the port to control the pressure wave propagated through the port by the termination of rate shaping.

Abstract: A fuel pumping apparatus is disclosed which comprises a pumping plunger reciprocable within a bore. A spill valve communicates with the bore. A pilot piston is exposed to the fuel pressure within the bore, the pilot piston being arranged to move under the action of the fuel pressure to supply a pilot quantity of fuel to an injector. The pilot piston is arranged so that, in one position, only part of an end face thereof is exposed to the fuel pressure within the bore.

Abstract: A control valve, preferably for use with a fuel injector, includes a valve body defining a solenoid cavity, an inlet passage, an outlet passage and a metering passage extending between the solenoid cavity and the outlet passage. A solenoid is mounted in the solenoid cavity. A valve member has one end attached to the solenoid and is positioned to reciprocate in the valve body between an open position in which the inlet passage is opened to the outlet passage and a closed position in which the inlet passage is closed to the outlet passage. The inlet passage is in fluid communication with the solenoid cavity via the metering passage when the valve member is in its open position. Appropriate sizing of the metering passage can prevent secondary injections by providing adequate pressure relief to the solenoid cavity while also substantially damping any pressure waves that may travel to the solenoid cavity through the metering passage.

Abstract: An injection nozzle comprises a valve needle engageable with a seating. The needle includes a surface arranged such that when the needle occupies a fully lifted position, part of the surface is exposed to the fuel pressure within a control chamber whilst a second part of the surface is exposed to the fuel pressure within a second chamber. Independent restricted passages provide communication between the control and second chambers and a supply line. A control valve communicates with the second chamber to control operation of the injection nozzle. The control valve is actuated by an electromagnetic actuator having a core arrangement--armature air gap of tapering axial length.

Abstract: A fuel injection system comprises a pumping plunger slidable within a bore and arranged to supply fuel to an injector nozzle. A spill valve communicates with the bore to control the fuel pressure applied to the nozzle. The nozzle includes a valve member biased into engagement with a seating by a spring, the spring engaging a piston member at least part of the end of which remote from the spring is exposed to the fuel pressure in the bore. The spill valve includes a flow connection which communicates by way of a restrictor with a drain. The restrictor is formed by the piston member and cylinder within which the piston member is slidable.

Abstract: A fuel injector having a plurality of spaced apart apertures modifies the rate of fluid flow of the fuel injectors. The apertures are sequentially opened by movement of the intensifier piston in a piston bore passing actuating fluid flow at an increasing rate to a piston pressure chamber defined by a first end surface of the intensifier piston, a closed end surface of the piston bore and the cylindrical surface of the piston bore. The opening of the spaced apart fluid delivery apertures provide a stepped rate trace. The stepped rate trace allows less fuel to be injected into the combustion chamber by injecting the fuel slower during the early phase of the combustion process where combustion is less harsh.

Abstract: A pump/injector arrangement comprises a pump including a pump chamber arranged to communicate through a fuel line with an injector. A valve is provided within the injector to control whether or not fuel is able to flow from the fuel line to a control chamber. The control chamber communicates with a low pressure reservoir through a restricted passage. A by-pass is provided to permit fuel to flow from the reservoir by-passing the restricted passage.

Abstract: An improved nozzle assembly for servo-controlled fuel injectors is provided which includes a needle valve control device including a rate shaping control device for effectively producing a predetermined time varying change in the flow rate of fuel injected into the combustion chamber during an injection event so as to reduce emissions. The rate shaping control device includes an injection control valve positioned along a drain circuit connected to a control volume positioned at one end of the needle valve element. The injection control valve includes an actuator for controlling the flow of fuel through the drain circuit to variably control the rate of movement of the needle valve element between the open and closed positions so as to provide the desired shaping to the flow rate of fuel into the combustion chamber.

Abstract: A rapid-response solenoid-operated fuel injector for diesel engines is provided which includes a solenoid-operated valve member and a needle valve. The solenoid-operated valve member selectively establishes fluid communication between a fuel inlet and a fuel outlet. The needle valve is moved to selectively open and close a spray hole through which the fuel is sprayed. The solenoid-operated valve member is exposed at its head to the fuel pressure within a pressure control chamber supplied from the fuel inlet and has formed therein a pressure balancing chamber communicating with the pressure control chamber through a first orifice. The pressure of fuel within the pressure balancing chamber acting on the solenoid-operated valve member to block the fluid communication between the fuel inlet and outlet is balanced with the pressure of fuel within the pressure control chamber acting on the solenoid-operated valve member to establish the fluid communication between the fuel inlet and outlet.

Abstract: A hybrid hydraulic electronic unit injector (HEUI) assembly, having some characteristics of an accumulator-type assembly and some characteristics of a non-accumulator type assembly, is produced by designing the volume (V.sub.ACC) of the passageway downstream of an existing blowback prevention check valve of the assembly to be between 1.0 and 10.0 times the maximum quantity Q.sub.MAX of fuel injected during an injection event. The resulting hybrid assembly 1) exhibits a rising injection rate during at least the initial stages of the injection event and therefore exhibits benefits generally associated with non-accumulator type HEUI assemblies, and 2) exhibits a falling rate injection during at least the final stages of the injection event and therefore exhibits benefits generally associated with accumulator-type HEUI assemblies. The percentage of the injection event taking place under a falling rate increases generally proportionally with the ratio V.sub.ACC /Q.sub.MAX.

Abstract: This fuel injector for internal combustion engines makes the best use of the responsiveness of a piezoelectric element and the leakage resistance and fixing easiness of a solenoid type fuel injection nozzle, and secures a sufficient lift of a control piston. In this fuel injector, a control piston is connected to and controls a sliding movement of a needle valve, and a return spring provided in a fuel chamber urges the needle valve in the injection port closing direction, the lift of the control piston being controlled by a piezoelectric element which is adapted to be displaced in accordance with voltage variation. The displacement of the piezoelectric element is increased by the effect of lever and fulcrum of a displacement increasing mechanism, and the resultant displacement is transmitted to the control piston, whereby the lift of the control piston and needle valve is secured.

Abstract: An electromechanically actuated fuel injector and a solenoid stator assembly for an electromechanically actuated fuel injector are disclosed. The solenoid stator assembly comprises a cup shaped stator core assembly comprised of a plurality of magneto-conductive wire members of a predetermined length arranged in parallel, adjacent and abutting relationship relative to an adjacent wire member. These wire members are bound at one end thereof for some length less than the entire length of the wire members to form a central pole piece, and splayed umbrella like about the central pole piece at the opposite end thereof to form a first pole piece in concentrically spaced relationship relative to said center pole piece. The stator core thereby has a circular top portion and an open end disposed opposite said top portion and facing an armature in the fuel injector.

Abstract: The present invention provides direct control over the opening and closing of a fuel injector nozzle valve independent of fuel injection pressure or engine operating condition and allows for initial fuel injection rate shaping by controlling the opening velocity of the nozzle valve. The present invention further allows for control over the closing velocity of the nozzle valve thereby reducing stresses on the nozzle tip as the check engages the check seat while not adversely affecting the performance of the fuel injector. This results in lower tip wear and improved life of the fuel injector.

Abstract: A valve includes a housing having a high pressure inlet, a low pressure inlet, an outlet and first and second sealing surfaces. A pilot valve is disposed in the housing and includes a valve element movable between first and second positions. A movable spool is also disposed in the housing and includes third and fourth sealing surfaces engagable with the first and second sealing surfaces, respectively, carried by the housing to connect the outlet to the low pressure inlet when the valve element is in the first position and to connect the outlet to the high pressure inlet when the valve element is in the second position.

Abstract: An unit-type fuel injection device including a plunger for pressurizing fuel in a fuel pressurizing chamber, an injection nozzle which has a fuel reservoir and serves to inject the fuel pressurized in the fuel pressurizing chamber, and an electromagnetic valve which has a valve plug and serves to intercept fuel supply to the fuel pressurizing chamber, wherein the valve plug of the electromagnetic valve is provided with an intercommunication hole through which the fuel pressurizing chamber and the fuel reservoir of the injection nozzle intercommunicate with each other when the valve plug intercepts the fuel supply to the fuel pressurizing chamber.

Abstract: A metering valve for metering a fluid for a fuel injection valve for internal combustion engines, with a hydraulic displacement amplifier for converting the actuating displacement of a piezoelectric actuator into an increased stroke of the valve needle. Integrating the displacement amplifier spatially into the valve housing in an "O valve" to give a small overall volume is served by providing the lifting piston of the displacement amplifier with an end section of reduced diameter which projects into a recess in the operation piston of the displacement amplifier. A Belleville spring lying in the amplifier chamber bounded by the pistons presses the operating piston against the actuator, and a helical compression spring arranged in the recess concentrically to the end section presses the lifting piston against the valve needle.

Abstract: An electromagnetic fuel injection control valve positioned inside a fuel injector, i.e. a unit injector, for providing fast response and high pressure capability while minimizing the size and complexity of the injector. The control valve includes a valve housing having a supply inlet and fuel outlet, a center tube having a center passage and an annular valve seat, a control valve sleeve slidably mounted on the center tube and an actuator assembly having a coil spring, a stator and an armature. The control valve sleeve moves between an open position permitting fuel to flow between the supply inlet and the fuel outlet and a closed position which sealingly engages the annular valve seat for blocking the flow of fuel between the supply inlet and the fuel outlet. The coil spring biases the control valve sleeve in an open position and is positioned around the center tube. The stator is also axially positioned around the center tube and includes multiple poles.