Abstract: The present invention relates to a nozzle of a fuel injector that comprises a pivotably symmetrical nozzle body having a hollow space for introducing a nozzle needle, a nozzle tip that is provided at one longitudinal end of the nozzle body and has openings for discharging fuel, a housing contact surface that is provided at the other longitudinal end of the nozzle body and serves the pressing at a housing of a fuel injector, and an overhang surface that is provided in the longitudinal extent of the nozzle body between the nozzle tip and the housing contact service and that serves the placement of a nozzle clamping nut. The nozzle is characterized in that the minimal distance of the pivot axis of the nozzle body from the overhang surface is smaller than the minimal distance of the pivot axis of the nozzle body from the housing contact surface.

Abstract: Valve for an airbag system for a motor vehicle and airbag system for a motor vehicle The invention relates to a valve for an airbag system for a motor vehicle, having: a housing (20) which extends along a longitudinal axis (21) and surrounds a cavity (22) having a taper (17) and surrounds a control chamber; an electrically switchable pilot valve (15) which selectively seals or releases a pilot opening (6) of the control chamber (5); a piston (3) which is arranged in the cavity (22) and can be displaced along the longitudinal axis (21) relative to the housing (20); an equalization line (4, 18) which connects an inlet (1) of the valve (100) to the control chamber (5) for fluid communication, wherein: a sealing seat (2) is formed at the taper (17) in order to block a gas flow from the inlet (1) to an outlet (14) of the valve (100) in a closed position, in which the piston (3) is in contact with the sealing seat (2), and to release said gas flow in further positions; the control chamber (5) is arranged on a fi

Abstract: The present disclosure provides a high-pressure common rail fuel injector capable of achieving highly stable injection based on the throttling damping-accommodating effect in the present disclosure, comprising a fuel injector housing, a fuel pipe connector, an accumulator chamber, a fuel chamber control valve, a pressure fluctuation absorption assembly, a control valve assembly and a nozzle assembly; the accumulator chamber is installed in the fuel injector housing, and the fuel pipe connector is installed above the accumulator chamber; the fuel chamber control valve, the pressure fluctuation absorption assembly and the control valve assembly are installed in the fuel injector housing, and the nozzle assembly is arranged below the control valve assembly; and the accumulator chamber is separated into a main accumulator chamber, an auxiliary accumulator chamber and a fuel-return accumulator chamber.

Abstract: An ejector includes a nozzle, a body including a refrigerant suction port and a pressure increasing portion, a passage forming member inserted into the nozzle, and an actuation device moving the passage forming member. A nozzle passage includes a smallest passage cross-sectional area portion, a convergent portion, and a divergent portion. The passage forming member includes a tip portion which changes the passage cross-sectional area at the smallest passage cross-sectional area portion when the actuation device moves the passage forming member. A positive displacement amount is defined as an amount of a displacement of the passage forming member when the passage forming member is moved so as to increase the passage cross-sectional area at the smallest passage cross-sectional area portion. The tip portion has a shape in which an increase rate of the smallest passage cross-sectional area portion is increased according to an increase of the positive displacement amount.

Abstract: The pressing part includes an abutment part capable of being in contact with the inner peripheral surface of the pressing passage, and a depressed opposite part that is opposed to the exhaust port at a position away from the exhaust port in a perpendicular direction perpendicular to the displacement direction due to an outer peripheral surface of the pressing part recessed from the abutment part even when the abutment part is in contact with the inner peripheral surface of the pressing passage. When the abutment part is in contact with the inner peripheral surface of the pressing passage, a depression dimension of the depressed opposite part relative to the abutment part is set, such that an amount of fuel discharged from the valve chest is defined by the exhaust throttle part instead of a gap between the depressed opposite part and the inner peripheral surface of the pressing passage.

Abstract: A fuel injector device for injecting fuel into a combustion chamber of an internal combustion engine is provided in which the fuel injector includes a body having an upper chamber and a lower chamber, an annular shoulder between the upper and lower chambers, an armature assembly disposed in the upper chamber, and a pilot valve seat having an inlet orifice disposed in the lower chamber and an outlet orifice disposed in the upper chamber. The pilot valve seat has a shaft extending between the outlet and inlet orifice and an angled shoulder between the outlet and inlet orifice. The angle shoulder of the shaft prevents fuel flow around the shaft between the upper and lower chambers. The armature assembly is configured to move to an upward position and to a downward position, the shaft also being disposed within the armature assembly to guide the armature assembly between the upward and downward positions.

Abstract: A nozzle assembly for a fuel injector capable of withstanding high-pressures includes a nozzle chamber defined by a high-pressure containment sleeve, a tip component defining a nozzle outlet, and an injector stack component. A leakage path is defined between an injector body casing and an outer wall surface of the high-pressure containment sleeve and a needle valve member that opens and closes the nozzle outlet is out of contact with the high-pressure containment sleeve. The high-pressure containment sleeve has a hollow, cylindrical shape and has an inner wall exposed to fluid pressure inside the nozzle chamber that is free of stress concentrating surface features associated with heart shaped cavities in the prior art.

Abstract: A common rail fuel injector includes a control valve member unattached to, but trapped between, a push pin and a seat of an injector body. The push pin has a head that includes a contact surface and a crown that includes a stop surface. An air gap surface of an armature is located between a top of the head and the stop surface of the crown when the contact surface of the push pin is in contact with the armature. The stop surface of the crown is located between an air gap plane of a stator assembly and the air gap surface of the armature. The push pin, the armature and the control valve member are movable among a rest configuration, an injection configuration, and an over travel configuration.

Abstract: An assembly for a fuel injector that includes a piston that is decoupled from the needle of a needle valve. The piston is slidingly positioned in a disk bore. The portion of needle in the disk bore is smaller than the disk bore so as to prevent the disk bore from interfering with movement of the needle between seated and unseated positions. During periods of operation, the upper surface of the piston is engaged by a control volume of fuel that pushes the needle toward a seated position, while the needle pushes in an opposing direction against a lower surface of the piston. The surface area of the piston acted on by the control volume is larger than the upper portion of the needle that is typically acted upon by the control volume, thereby providing a larger force on the piston that keeps the needle in a seated.

Abstract: A fuel injector includes a body, a main valve body, a sub valve body, an electric actuator, and a valve-opening force transmission mechanism. The body houses a main passage through which fuel flows to an injection, and a sub passage branched from the main passage and through which the fuel flows to the injection port. The main valve body opens or closes the main passage, and the sub valve body opens or closes the sub passage. The electric actuator applies a valve-opening force to the sub valve body. The valve-opening force transmission mechanism transmits the valve-opening force of the sub valve body to the main valve body to open the main valve body in a condition that a valve-opening stroke of the sub valve body is greater than or equal to a predetermined amount.

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: The invention relates to a fuel injector and, in particular, to a common-rail injector for injecting fuel into a combustion chamber of an internal combustion engine with a multi-part injection valve element, which can be adjusted between an open position and a closed position. A first part and a second part of the injection valve element are coupled to one another via a hydraulic coupler, which is bounded radially by a first guide for the first part and by a second guide for the second part. According to the invention, at least some sections of the first and the second guide are surrounded at their outer radii by fuel under high pressure, and the pressure realized in the hydraulic coupler is lower than the pressure radially outside the guides.

Abstract: A tubular outer needle, slidably housed in a body, can communicate nozzle and suck chambers R1, R2 with each other and shut them from each other, and defines nozzle and suck chambers R1, R3. A rod-like inner needle, coaxially slidably housed in the outer needle, has a tip end portion movable into the suck chamber R2 at its lowermost position. In the range of small inner lift amount, an annular clearance is formed between an inner peripheral surface of an inner side wall defines the suck chamber R2 and an outer peripheral surface of an outer side wall of the needle tip end portion. Outer and inner lift amounts are regulated such that when fuel injection is started, the outer and inner lift amounts simultaneously increase from zero while when fuel injection is terminated, the inner lift amount returns to zero after the outer lift amount returns zero.

Abstract: Fuel injectors with intensified fuel storage and methods of operating an engine therewith. At least one storage cavity is provided in the intensifier type fuel injector, with a check valve between the intensifier and the needle chamber and storage cavity preventing loss of injection pressure while the intensifier plunger cylinder is refilling with fuel. This provides very efficient injector operation, particularly at low engine loads, by eliminating the wasted energy of compressing, venting and recompressing fuel for injection. Various injector designs and methods of operating the same in an engine are disclosed.

Abstract: A fuel injection device includes a cylinder that defines a pressure chamber at an end portion of a nozzle needle. A floating plate as a control member is placed in the cylinder. A cutout portion and multiple grooves are formed in the floating plate. The cutout portion and the grooves causes a gap between a large-diameter inner circumferential surface and an outer circumferential surface to communicate with the pressure chamber. The cutout portion and the grooves reduce a contact surface portion between the cylinder and the floating plate and divide the contact surface portion into multiple island portions. As a result, it is possible to reduce the contact surface portion.

Abstract: A fuel injector for a compression ignition internal combustion engine which comprises a fuel injection valve having an injection valve member which is moveable in use, under the influence of fuel pressure within an injection valve member control chamber acting upon it, between a closed position and an open position. The fuel injector further comprises a high pressure fuel supply passage to the injection valve member control chamber, and an actuator operable to open and close a discharge valve connected between the injection valve member control chamber and a fuel outlet passage to a low pressure reservoir or drain. A shut-off valve is provided in the high pressure fuel supply passage and the shut-off valve has a shut-off valve member which is moveable in use, under the influence of fuel pressure within a shut-off valve member control chamber acting upon it, between a closed position and an open position.

Abstract: In a method for injecting fuel into the combustion chamber of an internal combustion engine, the fuel is fed by at least one prefeed pump from a tank to at least one high-pressure pump and the high-pressure fuel fed by the high-pressure pump is supplied to the injector, wherein the injector has an injection nozzle with an axially movable nozzle needle protruding into a control chamber which can be fed with fuel under pressure and whose pressure is controlled by a control valve which opens or closes at least one inflow or outflow duct for fuel. Between the prefeed pump and the high-pressure pump, a partial volume of the fuel is branched off as a flushing volume and supplied to a flushing channel of the injector, wherein the flushing volume is directly supplied to the control valve such that the flushing volume flows at least partially through the control valve and preferably mixes with the fuel from the inflow or outflow duct, respectively.

Abstract: In a fuel injection device, a control body has a pressure control chamber, an inflow port and an outflow port. The inflow port and the outflow port are opened at an abutting surface exposed to the pressure control chamber. In the pressure control chamber is arranged a floating plate for pressing the abutting surface by a pressing surface with the pressure of the fuel to interrupt communication between the inflow port and the pressure control chamber. The abutting surface of the control body is provided with an outer opposite surface portion opposite to an outer edge of the pressing surface in a displacement axis direction of the floating plate, and the outer opposite surface portion has a special depressed portion that is depressed in the displacement axis direction and that extends along the shape of the outer edge of the pressing surface.

Abstract: A common rail fuel injector includes a fuel inlet, a set of nozzle outlets, a drain outlet, a nozzle chamber and a needle control chamber. A needle control valve includes a ceramic control valve member movable between a closed position in contact with a flat valve seat to block the needle control chamber from the drain outlet, and an open position at which the needle control chamber is fluidly connected to the drain outlet. A solenoid actuator is mounted in the injector body and includes an armature movable between an overtravel position and an energized position, but the armature has a stable un-energized position between the overtravel position and the energized position. A needle valve member is positioned in the injector body and includes an opening hydraulic surface exposed to fluid pressure in the nozzle chamber, and a closing hydraulic surface exposed to fluid pressure in the needle control chamber.

Abstract: The invention relates to a ball valve for adjusting a flow of a fluid medium. The ball valve includes a valve seat and a rounded closing element, in particular a valve ball. Furthermore, the ball valve has an inlet with a choke valve and one diffuser arranged between the choke valve and the valve seat. The diffuser includes a constriction on the side facing the valve seat.

Abstract: Providing a fuel injection valve of the accumulator injection system, whereby the surge pressure caused by the change of the fuel injection rate when the nozzle needle begin to be seated on is reduced or lessened; the deterioration as to the fuel injection performance and the strength of the injection valve components the deterioration which is caused by the surge pressures is prevented. A fuel injection valve of the accumulator injection system, the fuel injection valve including: a nozzle 1, a nozzle needle 2, and a control rod 23; wherein, the control rod is provided with a groove whereby the groove communicates the high pressure fuel passage prior to a fuel injection shot; the groove is disconnected to the high pressure fuel passage and the fuel is injected into an engine combustion chamber during the fuel injection shot; the groove communicates with the high pressure fuel passage at the end of the injection shot.

Abstract: In a fuel injection device, a pressure control valve is configured to make communication between an outflow port and a return channel and to interrupt the communication so as to control pressure of a fuel in a pressure control chamber, a valve member is configured to open and close a valve portion in response to the pressure of the fuel in the pressure control chamber, and a pressing member is arranged to be reciprocated and displaced in the pressure control chamber. The pressing member has an outer wall surface portion that is opposite to an inner wall surface portion of the control body to be capable of contacting the inner wall surface portion of the control body, and at least one of the outer wall surface portion of the pressing member and the inner wall surface portion of the control body is provided with a recess portion that is recessed to a side separated from the other one of the outer wall surface portion of the pressing member and the inner wall surface portion of the control body.

Abstract: The invention relates to an injector for injecting fuel into combustion chambers of internal combustion engines. According to the invention, a valve seat of a control valve is designed as a flat seat that has a planar valve seat surface. A circumferential edge located on the face of a sleeve of the control valve rests on the planar valve seat surface when the control valve is closed.

Abstract: A method of operating a fuel injector having a piezoelectric actuator for controlling movement of an injector valve needle comprises: (a) prior to an initial fuel injection event, reducing the voltage across the actuator at an initial rate so as to de-energize the actuator; (b) increasing the voltage across the actuator at a first rate in order to initiate an initial fuel injection event of a first fuel injection sequence; and (c) reducing the voltage across the actuator at a second rate in order to terminate the initial fuel injection event. The method may further comprise the step of: (d) increasing the voltage across the actuator at a third rate, which is lower than the first rate, so as to de-energize the actuator but without initiating an injection event, once the initial fuel injection event has terminated and before a subsequent fuel injection event is initiated.

Abstract: A component includes a transmission arrangement for transmitting a force between an actuator and a control valve. The transmission arrangement includes a post that is associated with the actuator. The control valve is displaceable to an open position from a closed position when an opening force is applied to the control valve that is greater than a closing force provided to the control valve. The transmission arrangement is disposed in the component between the post and the control valve actuator and arranged to mechanically transmit by physical contact an actuator force from the post to the control valve when the post begins to travel towards the extended stroke position, and hydraulically amplify the actuator stroke between the post and the control valve when the post travels from the retracted stroke position to the extended stroke position.

Abstract: A low leakage large bore fuel system includes a common rail fluidly connected to at least one of a source of heavy fuel oil and a source of distillate diesel fuel. A plurality of fuel injectors are fluidly connected to the common rail and each include a cooling inlet and a cooling outlet. Each fuel injector also includes an electrical actuator coupled to a direct operated nozzle check valve by a pilot valve member and a control valve member. Fuel leakage is reduced between injection events by equalizing pressures in a pilot control chamber and an intermediate control chamber that are separated by a guide surface of the control valve member. Also, between injection events the pilot valve member blocks a drain outlet from a common rail inlet of the fuel injector.

Abstract: An injector includes a nozzle body, a main body including a supply port on the outer peripheral surface of the main body and a high pressure passage, and a fuel pressure sensor on an outer peripheral surface of the main body to detect fuel pressure. The high pressure passage has a first passage extending from the supply port in a radial direction of the main body, and a second passage extending from a fuel downstream end portion of the first passage toward an injection hole in an insertion direction of the nozzle body. The supply port and the sensor are diametrically opposed to each other. The main body includes a sensor passage, which branches from the high pressure passage to extend from the fuel downstream end portion of the first passage in an imaginary extension of the first passage so that fuel flows into the sensor through the sensor passage.

Abstract: An injection system for injecting fuel has an actuator, a pilot valve with a valve mushroom, and a supply throttle. The control chamber encompasses a control piston, a first discharge throttle, a first sealing edge for forming a first sealing seat along with the valve mushroom, a second sealing edge of a piston chamber with a valve piston, the second sealing edge forming a second sealing seat along with the valve piston during a maximum actuator working lift for sealing the piston chamber and the valve chamber from each other; and a second discharge throttle connecting the piston chamber to the low-pressure zone between the first and the second sealing edge, wherein d1>d2>d3, d1 are the minimum diameter of the first discharge throttle, d2 being the minimum diameter of the second discharge throttle, and d3 being the minimum diameter of the supply throttle.

Abstract: A unit fuel injector (30) has a boundary edge filter. A first endless annular internal space (100) is open to a holes (92) forming a fuel inlet port, a second endless annular internal space (102) that is spaced axially of the first endless annular internal space and through which fuel is supplied to an injection mechanism, and a series of circumferentially spaced apart, axially extending channels (104) through which fuel can pass from the first endless annular internal space to the second endless annular internal space.

Abstract: A fuel injection valve includes a needle for opening or closing an injection hole. The needle moves in response to a fuel pressure in a control chamber. The fuel injection valve includes an electromagnetic valve which opens or closes a discharge passage for changing pressure in the control chamber to actuate the needle. A narrow part is provided in the discharge passage. The narrow part is formed to shorten a length along a flow direction. The shortened narrow part can suppress pulsations. Therefore, it is possible to accurately control injection quantity, since a variation of closing speed of the armature caused by the pulsations can be suppressed.

Abstract: A fuel injector and a method of assembly includes a determination of various flow areas through clearances or openings formed in various components of the injector. With the various flow areas determined, the various components can be classified according to their flow areas such that sets of components can be selected having desirable flow area characteristics for assembly of the fuel injector.

Abstract: The invention relates to a fuel injector for injecting fuel into a combustion chamber of an internal combustion engine, which fuel injector comprises an injection valve element, for opening and closing at least one injection opening and a pressure booster, by way of which fuel which is at system pressure is compressed to injection pressure. The pressure booster is actuated via a first control valve and the injection valve element is actuated via a second control valve. The pressure booster comprises a pressure booster piston which is assigned a spring element which is supported by way of one side on the injector housing and by way of the other side on the pressure booster piston. The pressure booster piston delimits a compression chamber, a differential pressure chamber and a control chamber.

Abstract: Three-way valves having reduced leakage and fuel injectors using the same. Three-way spool poppet valves are disclosed having a spool with a poppet valve thereon cooperating with a seat on the valve housing to provide a substantially leak free valve closing in one direction characteristic of a poppet valve while preserving the advantages of a spool valve. Three-way ball valves are also disclosed having substantially leak free valves closing in both directions, but further including reduced short circuit losses due to direct flow from a high pressure supply to a low pressure vent during transition of the ball from one position to the opposite position. Fuel injectors with direct needle control using the three-way valves of the present invention are also disclosed.

Abstract: The present invention relates to a fuel injector for injecting fuel into a combustion chamber of an internal combustion engine, having a valve piston that is displaceably guided in an injector body in terms of lifting motions, whereby the lifting motion of the valve piston can be controlled by a control valve. The control valve has a valve needle with a guide bore, so that the needle is displaceably guided in the direction of a lifting axis in terms of lifting motions. A guide section integrally formed on an end of a valve piece extends into the guide bore for the displaceable guidance of the valve needle in terms of lifting motions. Along the lifting axis a vertical bore extends through the valve piece into the guide section, such that fuel is able to flow through the bore from a control chamber into an annular chamber introduced between the guide bore and the guide section for controlling the lifting motion of the valve piston.

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: To provide a fuel injection device capable of reducing the amount of fuel discharging to the outside. The fuel injection device is provided with the nozzle body, the injection control valve, and the close assistance piston. In the nozzle body, the first fuel chamber and the nozzle valve close chamber are formed. The injection control valve advances to a first position, thereby allowing the first fuel passage to be communicated with the first fuel chamber and blocking access from the first fuel chamber to the third fuel passage, and the injection control valve retreats to a second position, thereby blocking access from the first fuel passage to the first fuel chamber and allowing the first fuel chamber to be communicated with the third fuel passage. The close assistance piston prevents fuel in the first fuel chamber from discharging to the outside of the fuel injection device.

Abstract: The invention relates to a fuel injector having a coupler. The reciprocating movement of an actuator is transmitted by the coupler to a pin-shaped injection valve member which is guided into the nozzle body. The coupler has a valve piston and a coupler sleeve, and the valve piston is displaced in the inner diameter area of the coupler sleeve. The inner diameter of the coupler sleeve is greater than the outer diameter of the injection valve member. The difference between the inner diameter of the coupler housing and the outer diameter of the injection valve member is 0.2 mm or less.

Abstract: The invention relates to a fuel injector, in particular a common rail injector, for injecting fuel into a combustion chamber of an internal combustion engine. The fuel injector has an injection valve element which is adjustable between a closing position and an opening position and which is switchable by means of a control valve. The control valve has a sleevelike control valve element that is adjustable along an adjustment axis and in its closing position rests sealingly on a control valve seat element. According to the invention, it is provided that the control valve seat element is disposed movably relative to the adjustment axis of the control valve element.

Abstract: A fuel system includes a plurality of fuel injectors fluidly connected to a common rail. Each of the fuel injectors has at least one body component and includes an intensifier control valve for controlling movement of an intensifier piston, a needle control valve for controlling movement of a needle valve member, and exactly one electrical actuator coupled with the intensifier control valve and the needle control valve via a coupling linkage. The intensifier control valve and the needle control valve each include a valve member that is movable with respect to a valve seat. The electrical actuator includes an intermediate position during which the valve member of one of the intensifier control valve and the needle control valve is in contact with the respective valve seat, and the valve member of the other of the intensifier control valve and the needle control valve is out of contact with the respective valve seat.

Abstract: A fuel injector comprising a nozzle having a nozzle needle which is moveable with respect to a first needle seat to control fuel delivery through a nozzle outlet. The injector includes a nozzle control valve for controlling fuel flow into a control chamber through a first passage to pressurise the control chamber, and for controlling fuel flow out of said control chamber through said first passage to depressurise the control chamber. Movement of the nozzle needle is controlled by fuel pressure within the control chamber, such that pressurising the control chamber causes the nozzle needle to be urged against the first needle seat to close the nozzle outlet, and depressurising the control chamber causes the nozzle needle to lift from the first needle seat to open the nozzle outlet. The nozzle needle defines, at least in part, a restricted passage through which fuel can flow into the control chamber as the control chamber depressurises.

Abstract: A fuel injector and a method of assembly includes a determination of various flow areas through clearances or openings formed in various components of the injector. With the various flow areas determined, the various components can be classified according to their flow areas such that sets of components can be selected having desirable flow area characteristics for assembly of the fuel injector.

Abstract: A metering servovalve for a fuel injector of an internal combustion engine has an electro-actuator and a fixed valve body, which defines a control chamber communicating with an inlet and with an outlet channel. The outlet channel has at least one calibrated restriction and exits through the lateral surface of an axial stem, on which a sleeve slides, in a substantially fluid-tight manner, to open/close the outlet channel and so vary the pressure in the control chamber. The outlet channel is closed by an end portion of the sleeve that is elastically deformable in a radially outward direction, under the thrust of the fuel pressure, to increase the diameter at which the seal against the valve body is formed, with respect to a non-deformed state, and to generate an axial unbalancing force on the sleeve upon opening when the outlet channel is closed.

Abstract: A mechanically actuated electronically controlled fuel injector (MEUI) includes a first electrical actuator that controls the position of a spill valve, and a second electrical actuator to control pressure on a closing hydraulic surface associated with a directly operated nozzle check valve. The fuel injector is actuated via rotation of a cam to move a plunger to displace fuel from a fuel pumping chamber either to a spill passage, or at high pressure out of a nozzle outlet of the fuel injector for an injection event. The minimum controllable fuel injection quantity, especially as it relates to small closely coupled post injections following a large main injection, is accomplished by the inclusion of a Z orifice passage that maintains a fluid connection between a needle control chamber and the nozzle supply passage.

Abstract: A fuel injector for an internal combustion engine is proposed having a directly actuatable injection valve element. The fuel injector has a nozzle needle, axially guided in a nozzle body, and an actuator accommodated in an injector housing. The nozzle needle is connected to a coupling piston on the nozzle-needle side and the actuator is connected to a coupling piston on the actuator side. The coupling piston on the actuator side acts on a coupling chamber and the coupling piston on the nozzle-needle side acts on a control chamber. The nozzle needle is lifted from a nozzle-needle sealing seat as a function of the pressure in the control space. An intermediate plate is provided between injector housing and nozzle body. The plate has a conduit hydraulically connecting the coupling chamber to the control chamber. The conduit contains a hydraulic throttle which has at least two sections having different cross sections of flow.

Abstract: An apparatus for injecting fuel into an internal combustion engine having a fuel injector acted on with highly pressurized fuel actuated by means of a metering valve device that is able to control the pressure in a pressure booster control chamber so that in a pressure booster pressure chamber delimited by a pressure booster piston which can be filled via a check valve with high-pressure fuel and communicates with an injection valve member pressure chamber, the pressure booster piston increases the pressure, causing an injection valve member for injecting fuel to open.

Abstract: A common rail single fluid injection system includes fuel injectors with one or two control valve assemblies with the ability to produce ramp, square and split injection rate shapes. This is accomplished by including a check speed control device disposed between a first and second check control chamber within a cavity defined by the injector body. The control valves and check speed control device control the speed of a check by controlling the flow of fuel out of the first and second check control chambers.

Abstract: A fuel injector injects high-pressure gaseous fuel directly into a cylinder of an engine. A small amount of liquid fuel is used in the injector to lubricate sliding portions of the fuel injector in addition to utilizing it as a medium for transmitting driving force. The fuel injector includes a nozzle member having injection holes at its elongated end and a needle slidably disposed in an elongated center hole of the nozzle member. The needle is driven by pressure of the liquid fuel introduced into a control chamber to open or close the injection holes. The pressure in the control chamber is controlled by a switching valve which is in turn driven by an actuator such as an electromagnetic or piezoelectric actuator. The liquid fuel is injected together with the high-pressure gaseous fuel after lubricating the sliding portions between the nozzle member and the needle.

Abstract: A control valve arrangement for use in controlling fuel pressure within a control chamber (30) includes a control valve member (32) which is movable between a first position in which the control chamber (30) communicates with a source of high pressure fuel, and a second position in which the control chamber (30) communicates with a low pressure fuel drain and communication between the control chamber (30) and the source of high pressure fuel is broken. The control valve arrangement also includes restricted flow means (55, 70, 86) for restricting the rate of flow of fuel from the control chamber (30) to the low pressure fuel drain when the control valve member (32) is moved from the first position to the second position.

Abstract: Provided is the structure of a control valve of accumulator fuel injection equipment wherein an adverse effect by bounce can be reduced by a low-cost means without requiring any special device in the control valve structure of accumulator fuel injection equipment.

Abstract: A fuel injector having an injector body and a fuel inlet communicates with a high-pressure fuel source outside the injector body and including an actuator received in a hollow chamber from which a high-pressure inlet extends to an injection valve member. Depending on the pressure in the first hydraulic chamber, fuel is injected into a combustion chamber of an internal combustion engine when the injection valve member lifts from a seat. The actuator acts directly upon a stepped piston which defines the first hydraulic chamber and actuates a control piston. The injection valve member is guided in the control piston.