Abstract: A fuel injection apparatus for a fuel injector nozzle includes a moveable valve needle slideably located within a nozzle body, the nozzle body having an internal surface defining a valve seat between a fuel supply path and fuel outlets. The valve needle includes an obturator piston that is engagable with an axial fuel outlet and a two-stage lift mechanism for enabling lift of the valve needle. In a first stage lifted position of the valve needle, the valve face is spaced apart from the valve seat, and the obturator piston is positioned such that a fuel flow passage is opened between the obturator piston and the axial fuel outlet. In a second stage lifted position, the valve face is spaced further apart from the valve seat and the obturator piston is positioned such that the fuel flow passage between the obturator piston and the axial fuel outlet is substantially closed.

Abstract: A fuel injector having an injection nozzle comprising a nozzle body being provided with a nozzle bore, an outer valve received within the nozzle bore and being engageable with a first seating to control fuel delivery through a first set of one or more nozzle outlets. The outer valve is provided with an outer valve bore within which an inner valve is received the inner valve being engageable with a second seating to control fuel delivery through a second set of one or more nozzle outlets. The fuel injector further includes an injection control chamber for fuel and pressure control means for controlling the pressure of fuel within the injection control chamber.

Abstract: A fuel injection metering valve has a first fuel outlet for supplying fuel to a first accumulator volume, a second fuel outlet for supplying fuel to a second accumulator volume, valving for controlling fuel flow to the first and second fuel outlets, a first flow path for exposing the valving to fuel pressure representative of fuel pressure in the first accumulator volume and a second flow path for exposing the valving to fuel pressure representative of fuel pressure in the second accumulator volume. The valving is responsive to the representative fuel pressures to control the fuel supply from the second fuel outlet to the second accumulator volume as a function of the fuel pressure in the first accumulator volume. The fuel injection metering valve can be used in a dual-fuel fuel injection system to control the flow of one fuel such that it follows the controlled pressure of a different fuel, so that it is not necessary to provide duplication control components in the fuel injection system.

Abstract: In a device for the injection of fuel into the combustion chamber of an internal combustion engine, including an injector nozzle and a nozzle needle guided in a longitudinally displaceable manner within the injector nozzle for selectively releasing and blocking the fuel flow to the injection openings, the nozzle needle is at least partially surrounded by a nozzle prechamber, wherein a control element determining a supply cross-section for the fuel flow to the injection openings is arranged in the nozzle prechamber.

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.

Abstract: A fuel injection system is disclosed. The fuel injection system has a nozzle member configured to receive fuel and having at least one injection orifice and a valve disposed with the nozzle member and movable between an open position at which fuel flows through the at least one orifice and a closed position at which fuel flow through the at least one orifice is blocked. The fuel injection system also has an actuator coupled to the valve and configured to move the valve between the open position and the closed position in response to a signal applied thereto and a controller in communication with the actuator, the controller being configured to apply to the actuator an ultrasonic frequency signal such that the valve remains at or between the open position or the closed position and vibrates at the ultrasonic frequency.

Abstract: A common rail fuel injection system includes a piezo intensifier fuel injector that includes a plurality of components. Among these are a needle valve member, an intensifier piston, a first piezo stack electrical actuator and a second piezo stack electrical actuator. These components have a first configuration at which the needle valve member blocks a nozzle outlet of the fuel injector, and a shoulder of the intensifier piston is exposed to fluid pressure in a common rail. The components have a second configuration at which the nozzle outlet is fluidly connected to the common rail for a low pressure injection event. The components have a third configuration at which the nozzle outlet is fluidly blocked from the common rail, but movement of the intensifier displaces fluid through the nozzle outlet for a high pressure injection event.

Abstract: A fuel injector for use in an internal combustion engine includes a valve needle which is engageable with a valve needle seat to control fuel injection through an injector outlet. An actuator, typically in the form of a piezoelectric actuator stack, is arranged to control fuel pressure within a control chamber and a surface associated with the valve needle is exposed to fuel pressure within the control chamber. A load transmitter, preferably in the form of a motion inverter, transmits movement of the actuator to the valve needle. The load transmitter includes a bellows arrangement which is compressible and expandable in response to said actuator movement so as to vary fuel pressure within the control chamber, thereby to control movement of the valve needle relative to the valve needle seat. A piezoelectrically operable injector is operable in an energize-to-inject mode to provide efficient opening of the valve needle and to enable rapid closure of the valve needle.

Abstract: In a fuel injection nozzle including multiple nozzle hole groups each having multiple solitary nozzle holes, a group distance C between two of the nozzle hole groups is 0.8 or more times larger than an in-group hole distance ? in a nozzle hole group. The group distance C is the minimum interval of inter-group intervals that are formed between (i) peripheral boundaries of solitary nozzle holes belonging to a first nozzle hole group and (ii) peripheral boundaries of solitary nozzle holes belonging to a second nozzle hole group adjacent to the first nozzle hole group. The in-group hole distance ? is the minimum of intervals between peripheral boundaries belonging to each nozzle hole group.

Abstract: A fluid injection valve has an inlet, which is set up to receive fluid from a supply line, and which is connected to a chamber, a fluid outlet, which is connected to the chamber, and which is set up to allow fluid to flow out of the fluid injection valve, and a valve arrangement, having a valve seat and a valve member, the valve member being set up to execute opening and closing movements relative to the valve seat. A linear actuator is set up to move the valve member relative to the valve seat, and a spring arrangement exerts on the valve member a spring force which is dependent on the fluid pressure prevailing in the chamber.

Abstract: An atomization system for fuels, particularly for charging a chemical reformer for obtaining hydrogen, features at least one metering device, accommodated in a supporting device, for metering fuel into a temperature-adjusted substance stream, which introduces the fuel directly into the temperature-adjusted substance stream without the interpolation of a supply line.

Abstract: A control device (52) of a fuel injection valve has a mushroom-shaped intermediate valve member (56) which is guided with a sliding fit (58?) in a first intermediate plate (12). An injection valve member (28), which has a control piston (28?), for opening and closing injection openings in order to realize intermittent injection processes defines a control space (54) together with a guide sleeve (36) and the lower face (12a) of the first intermediate plate (12). A second intermediate plate (14) is situated between the first intermediate plate (12) and a housing body (10), and has a valve space (70) which is hydraulically connected to the end side of a shank (58) of the mushroom-shaped intermediate valve member (56).

Abstract: A fuel injection device includes a fuel injection valve for injecting fuel, which is distributed from a pressure-accumulation vessel. A pressure sensor is located in a fuel passage, which extends from the pressure-accumulation vessel to a nozzle hole. The pressure sensor is located closer to the nozzle hole than the pressure-accumulation vessel. A storage unit stores individual difference information obtained by an examination. The individual difference information indicates an injection characteristic of the fuel injection valve and indicates at least one of an injection response time delay between an injection start point and a time point, at which a fluctuation is caused by the start of fuel injection in detected pressure of the pressure sensor, and a parameter for calculating the injection response time delay.

Abstract: The invention relates to an injector for injecting fuel into a combustion chamber. The injector comprises at least one spray orifice with an inlet opening and an outlet opening. The spray orifice has a device for specifically producing cavitation at the outlet opening in order to remove deposits from the outlet opening that are produced during operation.

Abstract: A charge control unit controls electricity charged to a piezo element, which is for actuating a backpressure control valve so as to control backpressure applied to a valve element for a fuel injection valve. The backpressure control valve is configured to start to decrease the backpressure to actuate the valve element to open an injection port of the fuel injection valve when voltage of the electricity exceeds a threshold. A charge unit increases the voltage by repeating increasing and decreasing a drive current, which is supplied to the piezo element, for multiple times for charging the piezo element. A switching unit alternates the increasing and the decreasing such that the voltage exceeds the threshold in an intermediate period in a middle of a specific increasing period among multiple increasing periods, in each of which the drive current increases.

Abstract: The fuel injector includes an orifice plate being situated downstream from a valve-seat body having a fixed valve seat, the orifice plate having at least one outlet opening. Provided directly upstream from the outlet openings is an inflow opening having an annular inflow cavity. The valve-seat body covers the inflow cavity in such a way that the downstream outlet openings of the orifice plate are covered. A boundary surface of the valve-seat body lying opposite the orifice plate is designed such that, beginning at an exit opening, the height of the inflow opening decreases continuously in a first section up to the at least one outlet opening, while the height of the inflow opening in a second, radially outer section remains largely constant. The fuel injector is particularly suitable for use in fuel injection systems of the mixture-compressing internal combustion engines having external ignition.

Abstract: A fuel injector is described that includes a polymeric housing, a metering assembly, and a closure assembly. The polymeric housing includes a continuous polymeric bore that extends from a first external seal proximate an inlet to a second external seal proximate an outlet of the bore along a longitudinal axis. The metering assembly is disposed proximate the second external seal. The closure assembly is disposed proximate the metering assembly, and a portion of the closure assembly is contiguous to the polymeric bore and disposed between the first and second external seals. A method of maintaining leak integrity is described.

Abstract: A fuel injection apparatus with a deterioration detection device that includes a volume changing chamber, the volume of which is determined by fuel pressure inside the injector. After injector nozzle opens, the time for the volume changing chamber to change from an initial volume to a target volume is measured and used for calculating changes in nozzle orifice size. The value of orifice size change can be used for both diagnosing injector deterioration and compensating fuel flow rate in a feedback control. In addition to detecting injector deterioration and failures, the volume changing device also dampens effects of noise in fuel pressure to fuel flow rate control and decreases chances of after-injection and second injection.

Abstract: The invention relates to a fuel injection valve for fuel injection systems of self-igniting air-compression internal combustion engines. The fuel injection valve comprises an actuator, housed in a valve chamber, and a valve closing element that is actuated by the actuator by means of a valve needle. The valve closing element interacts with a valve face to give a sealing seat. The valve also comprises a transition piece that is attached to the actuator, and an expandable hose encompasses the periphery of the actuator and a part of the transition piece. The expandable hose is connected to the transition piece in an area of fastening.

Abstract: A fuel injector has a valve needle that has a maximum diameter at a flow-off edge, and a valve seat acting together with the valve needle using a sealing seat, the valve seat widening, starting from the sealing seat up to a discharge edge, and the flow-off edge of the valve needle being offset backwards, in relation to the flow direction, with respect to the discharge edge of the valve seat, when the fuel injector is closed. The flow-off edge of the valve needle is offset backwards with respect to the discharge edge of the valve seat in a predetermined range of 2 micrometers to 20 micrometers, in the direction of a longitudinal valve axis.

Abstract: A heating time period is decreased by that a valve body including a hollow valve shaft is arranged in a slidable manner in a cylindrical part of a casing on which a nozzle body with a valve seat is mounted at a front end thereof, a fuel is introduced from a fuel outlet port opening on a shaft wall of the valve shaft into a fuel path formed by the valve shaft and the cylindrical part, the fuel is heated to be injected from the nozzle body by a heater arranged at an outside of the fuel path of the cylindrical part, and a sleeve is mounted in the fuel path so that a large diameter part thereof closes the fuel path at an upper area of the fuel outlet port, while a fuel inlet port is formed on a small diameter part of the sleeve to introduce the fuel into the fuel path, so that the fuel path is narrowed to decrease an amount of the fuel to be heated by the heater.

Abstract: A control servo valve (8) is housed inside the casing (2) of an internal combustion engine fuel injector (1), and has a piezoelectric actuator (40), and a control chamber (13) having a fuel outlet passage (21); the outlet passage (21) comes out inside an annular chamber (34) defined by a fixed tubular portion (25) and by a shutter (32), which engages the tubular portion (25) in substantially fluidtight manner and is slid axially by the piezoelectric actuator (40) from a closed position, in which it closes the annular chamber (34) and is subjected to a zero axial resultant force by the fuel pressure, to an open position, in which the outlet passage (21) communicates with a discharge conduit.

Abstract: A fuel injector includes first and second electrical actuators positioned within an injector body. First and second pairs of electrical conductors extend from a socket connector outside of the injector body to the first and second electrical actuators, respectively. The electrical conductors extend through an elastomeric sealing member that seals against fuel leakage from the fuel injector. The elastomeric sealing member provides annular sealing ridges in sealing contact with an access passage of the injector body and includes individual conductor seal passages that form seals around the outer surface of the individual electrical conductors. The elastomeric sealing member includes features that facilitate assembly of the fuel injector in a manner that reduces risk of damage to the sealing strategy.

Abstract: An electrically operated injector (1) for feeding a gaseous fuel to a cylinder of an internal combustion engine, in particular for a motor vehicle, includes an electromagnetic actuator (2) acting on a mechanical interceptor member (3) arranged to free or intercept a passage (4) for the fuel from a feed conduit (61) to a delivery conduit (5) connected to an outlet (6), between the delivery conduit (5) and the interceptor member (3) there being positioned a seal element (40). This latter is carried by the interceptor member (3) and has a shape tapering towards the delivery conduit (5) in order to effectively intercept the fuel gas passage (4) and minimize the area of impact with an annular end portion (43) of the delivery conduit (5).

Abstract: The fluid injection valve has a first and second valve bodies fastened to each other, to bring a first end face of the first valve body into an intimate contact with a second end face of the second valve body. A first fluid passage in the first valve body is communicated with a second fluid passage in the second valve body. The first end face has a first depressed portion thereon, and the second end face has a second depressed portion thereon to be communicated with the first depressed portion to form a cavity to surround the first and second fluid passages.

Abstract: A fuel injection system for internal combustion engines, having a fuel injection nozzle supplied with fuel by a high-pressure fuel source, which fuel injection nozzle has a movable nozzle piston for opening and closing injection openings, an injection nozzle high-pressure chamber, and an injection nozzle control chamber. A pressure boosting device connected between the fuel injection nozzle and the high-pressure fuel source has a movable piston, a work chamber, and a high-pressure chamber, in which a filling connection which is open for filling the high-pressure chamber when the fuel injection nozzle is closed and is itself closed when the fuel injection nozzle is open.

Abstract: A fluid injector has a housing, an actuator and a valve body. The valve body has a cartridge (21) with a recess, that forms an injection nozzle on one end, and with a needle (22), that is arranged in the recess and closes the injection nozzle, if it rests with its seat area (224) on a needle seat (215) of the cartridge (21). The area (216) of the cartridge (21) adjacent to the needle seat (215) has a cylindrically-shaped outer contour and the needle (22) has a cylindrically-shaped area (223) adjacent to the seat area (224). The area (216) adjacent to the needle seat (215) and the cylindrically-shaped area (223) have the same diameter.

Abstract: A common rail injector for injecting fuel through a high-pressure channel includes a control chamber, a control valve, and a drive unit. The control chamber applies pressure to a nozzle needle. The control valve switches communication of the control chamber between the high-pressure channel and a low-pressure channel. The drive unit selectively sets a valve element of the control valve on a low-pressure side seat or a high-pressure side seat. The drive unit has an actuator and a slide pin member. The slide pin member slides inside a slide hole to transmit a force to the valve element. A diameter of the low-pressure side seat is less than or equal to a diameter of the high-pressure side seat. The pressure in the control chamber is exerted as an assistance force, so that a high-pressure side seat closing load becomes less than or equal to a low-pressure side seat opening load.

Abstract: The invention relates to a fuel injector having a solenoid valve for actuating an armature assembly which is configured in one piece or a plurality of pieces. A closing element is actuated via this in order to relieve the pressure in a control chamber. The armature assembly is guided in an armature guide which is fastened in the injector body by means of a valve-clamping screw. In a fixing region in the injector body, the armature guide has at least one circumferential recess which allows for deformation of the fixing region during fastening by the valve-clamping screw.

Abstract: A fuel injector for injecting fuel into a combustion chamber of an internal combustion engine, the injector having body and a nozzle holder in which an injection valve member is movably received, which injection valve member has a seat that opens or closes injection openings, and the injection valve member is actuatable via a piezoelectric actuator. The piezoelectric actuator actuates a first booster piston, in which a second booster piston, connected to the injection valve member is guided.

Abstract: A fuel injector comprising a valve member which is engageable with a valve seating to control fuel delivery from the injector, an actuator arrangement and an amplifier arrangement for transmitting movement of the actuator arrangement to the valve member. The amplifier arrangement comprises a piston member with which the actuator arrangement is cooperable to apply a retracting force to the piston member, and a control chamber for fluid. The amplifier arrangement preferably comprises a mechanical coupling arrangement for coupling movement of the piston member to the valve member upon application of an initial retracting force to the piston member.

Abstract: This invention relates to the injection of compressible gaseous fuel directly into the combustion chamber of a reciprocating piston-type internal combustion engine. In particular, the invention provides apparatus and methods for low-pressure, high-speed direct injection of compressed natural gas into a combustion chamber of an engine. Using the present invention, relatively low intake pressures of about 50 to about 150 PSIG yield high-speed (sonic and supersonic) gas flow through the diverging nozzle portion for injection into the combustion chamber. Preferably, the gas reaches supersonic velocity, approaching Mach 1.5 to 2.5.

Abstract: The hydrogen gas injector plug for diesel engines employs an injector plug for generating hydrogen gas from water. Pressurized hot water is pulsed into contact with a heated metallic catalyst. The pressurized hot water turns to steam and disassociates into a mixture of oxygen and hydrogen gases. The catalyst removes the oxygen gases from the gaseous mixture. The hydrogen gas expands into a combustion chamber and is burned therein, creating a pressure to drive an engine piston disposed in the combustion chamber.

Abstract: The injector includes a nozzle, a needle, a control chamber, a working fluid supply passage, an electric switching valve, a high-pressure gaseous fuel supply passage and a lubrication liquid fuel supply passage. The nozzle has an injection hole, through which high-pressure gaseous fuel is injected. The needle is axially reciprocably received in the nozzle to open and close the injection hole. The needle includes a sliding portion and a valve portion. The control chamber applies a pressure to the needle. The working fluid supply passage supplies liquid fuel to the control chamber. The electric switching valve controls an inflow/outflow of the liquid fuel to/from the control chamber. The high-pressure gaseous fuel supply passage supplies the high-pressure gaseous fuel to the injection hole. The lubrication liquid fuel supply passage supplies the liquid fuel from the working fluid supply passage to the sliding portion and the valve portion.

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 pressurizing piston has a head section, which contacts an axial end face of a piezoelectric actuator to receive displacement of the actuator, and a piston wall section, which is formed in a cylindrical shape and can move in an axial direction in response to the movement of the head section. The head section and the piston wall section are combined such that relative displacement therebetween is possible in a radial direction. An outer sleeve slidably holding an outer periphery of the piston wall section restricts radial movement of the head section. When an expansion-contraction direction of the actuator inclines with respect to the axial direction, inclination of the piston wall section is inhibited by a radial deviation caused between the head section and the piston wall section. Thus, pinching of the piston wall section to the outer sleeve is inhibited.

Abstract: A fuel injector with direct needle control has a nozzle needle guided in a nozzle body, and an actuator and a hydraulic pressure boosting unit that has an actuator pressure boosting piston connected to the actuator and a nozzle needle pressure boosting piston connected to the nozzle needle. The actuator pressure boosting piston and the nozzle needle pressure boosting piston both act on a coupler chamber. The nozzle needle pressure boosting piston contains a cylindrical chamber in which a control piston is axially guided, whose coupler chamber pressure surface is exposed to the coupler chamber and whose differential pressure chamber pressure surface is exposed to an inner differential pressure chamber contained in the cylindrical chamber. At its end oriented away from the coupler chamber, the nozzle needle pressure boosting piston is associated with an outer differential pressure chamber that communicates with the inner differential pressure chamber via a hydraulic connection.

Abstract: Stable spray characteristics (particle size, directivity, divergence angle of spray, and penetration force) are provided for individual nozzle holes, flows of fuel toward the nozzle holes are not interfered with each other, and further spray characteristics can arbitrarily be altered at respective nozzle holes. A whirler 11 for providing a whirling force to fuel is provided, and a whirl flow is formed in a cavity 20 downstream of a seal portion of a needle valve 16. A plurality of nozzle holes 13 are formed in an orifice plate 14, and openings on the cavity 20 side of the nozzle holes 13 are formed on substantially the same diameter with respect to the central axis of a fuel injection valve 1. Thus it becomes possible to cause fuel having inflow angle and high flow velocity to flow into the openings of the nozzle holes 13.

Abstract: The valve of the fuel cartridge nozzle is constituted by a valve body, a valve seat, a first compression spring urging the valve body to move toward the valve seat, a seal ring interposed between the valve body urged by the first compression spring and the valve seat, a valve stem disposed inside flow channel which is communicated with the liquid delivery port, and an inside plug supporting the first compression spring, and the valve of the inlet member of fuel cell is constituted by a valve body, a valve seat, a second compression spring urging the valve body to move toward the valve seat, a seal ring interposed between the valve body urged by the second compression spring and the valve seat, a valve stem disposed inside flow channel which is communicated with the liquid-receiving port, and a lower member supporting the second compression spring.

Abstract: A nozzle device has a nozzle holes for injecting sprays grouped into spray groups respectively in injection directions. The nozzle device has an injection axis extending through the center in the thickness direction thereof. The injection axis perpendicularly intersects with an imaginary plane, which is at a predetermined distance from the nozzle device. The nozzle holes respectively have passage axes from which imaginary lines are respectively extended. The imaginary plane and the imaginary lines therebetween have intersections respectively defining outer intersections and an inner intersection in at least one of the spray groups. Each of the nozzle holes is inclined at an inclination angle being determined in such a manner that: the outer intersections exist in a polygon or a circle, and the inner intersection exists inside the outer intersections.

Abstract: A relatively inexpensive robust attachment strategy that insures good perpendicularity between a valve member and an armature utilizes an intervening nut between the armature and valve member. A valve member is received in a guide bore of a valve body. A nut is threaded onto one end of a valve member. The armature is press fit onto a orientation neutral interface of the nut, and a fixture is utilized to set near perfect perpendicularity between an air gap plane of the armature and a centerline of the valve member. The armature is then welded to the valve member. The weld may be accomplished via laser welding while the valve assembly is firmly held in an appropriate position within the fixture. The valve assembly may be then incorporated into a fuel injector stack of components in a conventional manner.

Abstract: A fuel injector, particularly for the direct injection of fuel into a combustion chamber of an internal combustion engine, has an actuator for actuating a valve needle; at a spray-discharge end, the valve needle having a valve-closure member that, together with a valve-seat surface configured on a valve-seat member, forms a sealing seat at a seat-contact point; the valve-seat member and/or the valve-closure member being provided with at least one stiffness-reducing element.

Abstract: In the valve, fuel, flowing down as a valve side flow along the side of the valve, further flows down toward an orifice plate through a fuel path which closes and opens upon forward and backward movement of the valve, and is injected as a mist from each orifice. The valve moves forward and backward by sliding on a valve surrounding portion through a guide portion constituted by plural sliding guides arranged between the valve and valve surrounding portion. Since the sliding guides are tapered from the valve to the surrounding portion, the side flow from the guide portion has a flow velocity distribution biased toward the surrounding portion.

Abstract: The invention relates to a fuel injection valve for internal combustion engines having a valve body in which a blind hole is formed, with at least one injection opening proceeding from said blind hole. A longitudinally displaceable needle in the valve body has a valve sealing face formed at its end which faces towards the blind hole. The valve sealing face is formed from one or more conical faces, and the valve needle interacting, by means of a body seat, with said valve sealing face to control a fuel flow to the at least one injection opening. A needle tip adjoining the valve sealing face dips into the blind hole when the valve needle bears against the body seat, the needle tip being curved in a concave fashion directly adjacent to the valve sealing face.

Abstract: A fuel injection device has a nozzle body formed with an injection hole for injecting fuel and a nozzle needle reciprocating in the nozzle body to open and to close the injection hole. The nozzle needle has a sliding portion capable of moving in the nozzle body in a sliding manner, an insertion portion, of which diameter is smaller than that of the sliding portion, and a pressure receiving portion connecting the sliding portion with the insertion portion. The nozzle body has a guide portion for slidably holding the sliding portion and a fuel sump chamber formed on the injection hole side of the guide portion. The insertion portion is inserted through the fuel sump chamber. A clearance decreasing toward the fuel sump chamber is provided between the guide portion and the sliding portion.

Abstract: A fuel injection valve for internal combustion engines, having a valve body with a bore defined on its end toward the combustion chamber by a conical valve seat, with a valve needle disposed longitudinally displaceably in the bore and a sealing face with two sealing portions on its end toward the combustion chamber with the second conical face being disposed on the combustion chamber side of the first conical face. An annular groove extending between the conical faces has an end facing away from the combustion chamber which acts as a sealing edge upon contact of the valve sealing face with the valve seat. Recesses embodied in the valve seat and/or on the valve sealing face hydraulically connect the annular groove with a portion of the second conical face located on the combustion chamber side of the annular groove.

Abstract: A method of operating a fuel injector having a piezoelectric actuator that is operable by applying an electrical drive pulse thereto to activate and deactivate the injector. The method includes monitoring an electrical characteristic of the actuator during a predetermined time period, determining a time-domain data sample corresponding to the monitored electrical characteristic during the predetermined time period, determining a frequency spectrum signature corresponding to the time-domain data sample, and comparing the frequency spectrum signature of the monitored electrical characteristic to a predetermined frequency spectrum signature indicative of an injector event.

Abstract: A solenoid-type fuel injector assembly having at least one component formed of stabilized, solenoid-quality ferritic stainless steel. In a preferred embodiment, an austenitic fuel tube is laser-welded to an injector body and to a solenoid pole piece formed of the subject material. The stabilized, solenoid-quality ferritic stainless steel, preferably a free-machining grade thereof, comprises from about 10% to about 35% chromium, and at least one stabilizing element selected from the group consisting of titanium and columbium. Components thus formed are weldable, exhibit soft magnetic properties sufficiently strong for carrying a magnetic flux in a solenoid pole piece, have desired structural and mechanical properties, and reduce the susceptibility of a solenoid-type fuel injector to metallurgical sensitization and intergranular corrosive attack at weld sites.

Abstract: A fuel injector incorporates a flow control into the needle valve and valve body to regulate fuel flow through the injector. The flow control defines an initial pilot fuel flow path that is closed by needle valve movement away from the nozzle seat. A primary fuel flow path requires axial movement of the needle valve through a mid-range position in which neither fuel flow paths are open. At low engine speeds, the needle valve is not driven through its mid-range position and closes prior to being driven to its fully open position, resulting in a pilot injection. At higher engine speeds, the needle valve is driven through its mid-range position eliminating a distinct pilot injection to provide only rate shaping.

Abstract: A valve device and a method directly inject gaseous fuel into a combustion chamber. A rapid response in a simple and compact design is achieved by a piezoelectric, magnetostrictive, or electromagnetic actuator that acts on a transmission device that comprises at least two levers, which are connected in series to increase the lift of the actuator to actuate a valve. An associated sensor device detects the position of a valve element, such that the actuator can be controlled to reduce the free play between the actuator and the valve.