Abstract: A fuel injector for fuel injection systems of internal combustion engines has a valve needle (3) and, mechanically linked thereto, a valve closing body (4), which cooperates with a valve seat surface (6) disposed in a valve seat body (5) to form a sealing seat, and has a plurality of recesses (34), which are introduced in the valve seat body (5) downstream from the sealing seat. Situated downstream on the valve seat body (5) is a flow-through screen (31) in which, for each recess (34), at least one discharge orifice (7) is introduced, whose cross-section is smaller than that of the particular recess (34) and which is positioned such that its inlet cross-section is situated fully within the outlet cross-section of the particular recess (34).

Abstract: A fuel injector, in particular an injector for fuel injection systems in internal combustion engines, includes a valve needle (6) having a valve-closure member (7) which cooperates with a valve-seat surface (8) situated in valve-seat member (5) to form a sealing seat (9) and which has several injection orifices (4, 12) which are situated downstream from the sealing seat (9), and are sealed by sealing seat (9) against a fuel supply. A disk element (10) is arranged downstream from the sealing seat (9), the disk element (10) having at least one valve section (11), which changes its shape when the temperature changes. Valve section (11) is connected to a heating element (13) and is possibly covering an injection orifice (12).

Abstract: The invention relates to an injection system having a piezoelectric adjuster (10), a hydraulic booster (12) and a control valve (14). In continuous operation of the injection system, the stroke of the piezoelectric adjuster (10) can be transmitted to the control valve (14) via a hydraulic medium in the hydraulic booster (12). In addition, the piezoelectric adjuster (10) and the components of the hydraulic booster (12) are disposed relative to the control valve (14) such that at least a portion of the stroke of the piezoelectric adjuster (10) can be transmitted directly to the control valve (14). In the method according to the invention for operating a piezoelectric injector, in which the piezoelectric adjuster (10) is electrically excited and made to execute a stroke; in a first phase, the stroke is transmitted directly to a control valve (14); in a second phase, the stroke is transmitted hydraulically to a control valve (14); and the control valve (14) is opened by the stroke.

Abstract: An high pressure seal comprises a tube with a first end adapted to fit into a first bore of a first mating part and a second end adapted to fit into second bore of a second bore of a second mating part and allow fluid communication between the first bore and the second bore. The seal is expandable radially about an axis to form a seal between the first and second mating parts.

Abstract: A high-pressure fuel system for internal combustion engines, having a housing that contains two high-pressure bodies. The high-pressure bodies rest with contact surfaces at least indirectly against each other and are pressed against each other by means of a tensioning device. A supply conduit is embodied in the high-pressure bodies, which carries highly pressurized fuel and passes through the contact surfaces of the two high-pressure bodies. A sealing film is disposed between the two high-pressure bodies, which encompasses the passage of the high-pressure conduit and thus assures a favorable seal.

Abstract: A fuel injector (10), including a housing (12), an armature assembly (14), an injector needle (16), a needle seat (18), a needle guide (20), and a orifice disc (22) containing one or more orifice metering pathways (24). The needle guide (20) contains a center guide bore (26) and a plurality of filtering passageways (28). The plurality of filtering passageways (28) are used to filter fuel passing through the needle guide (20) and induce swirl in the fuel to improve atomization.

Abstract: Located between the frustoconical needle tip and the cylindrical needle shank of a nozzle needle of a fuel injection valve is a frustoconical needle portion, into which is introduced a peripheral groove. Through this kind of arrangement damping is capable of being set, depending on the position of the groove, during the axial movement of the nozzle needle.

Abstract: The invention relates to an injector for injecting fuel into the combustion chambers of an internal combustion engine. An injector body (3) is provided, which is movable in a housing (2) and whose vertical stroke motion relative to the housing (2) is effected by means of a control chamber (6) that can be pressure relieved via an actuator (10). Via the vertical stroke motion of the injector body (3), the closure or opening of a nozzle inlet line (21) to the injection nozzle (5) takes place. On the injector body, for stroke and/or pressure control of the injector (1), a first slide (23) and a second slide (25) are embodied, offset from one another.

Abstract: The fluid discharge device includes an axial drive device for giving an axial relative displacement to between a piston and a cylinder, a device for giving rotary motion, and a device for pressure feed of fluid. The ON/OFF control of discharge flow rate can be fulfilled by changing the fluid resistance of the discharge passage with the axial drive device.

Abstract: A firefighting nozzle capable of selectively producing only a solid stream, only a fog pattern or a combination of both. The passage for the fog liquid can be opened to a flushing position for flushing debris therefrom. A solid stream sleeve is removably attached to a nozzle body for allowing discharge of solid streams having different diameters. A valve ball having primary and secondary flow passages is movable to positions for supplying liquid therethrough to both solid stream and annular fog supply passages, or to only the annular fog supply passage while closing the solid stream passage.

Abstract: A device for discharging raw material-fuel includes a pressurizing means for discharging a liquid, a pressure application room (1) in fluid communication with a discharge nozzle, and a liquid discharge nozzle (2) positioned under the pressure application room to discharge the liquid. The nozzle portion has an aspect ratio (L/d) of 5 or more, with L being the length of the nozzle in the thickness direction of the nozzle portion and d being the diameter of the nozzle portion.

Abstract: A compact spray valve that provides an extended atomizing air cap for reaching between tightly spaced electronic components. The compact spray valve of the present invention includes an air body, a fluid control body and an extended atomizing air cap. The atomizing air cap along with a seat extension provides a plurality of laminar air flow conduits causing atomization of a fluid into a spray. The resulting spray pattern can be controlled to provide a narrow line spray pattern with clearly defined edges. Another embodiment of the present invention provides a flat spray pattern.

Abstract: A fuel injection valve for an internal combustion engine includes a valve body having a valve seat face. A valve member has a valve sealing face that interacts with the valve seat face for forming a sealing cross section. The valve member is displaceable along an axial direction in the valve body. The valve body has a wall with injection holes formed therein which are provided downstream of the sealing cross section as seen in a fuel flow direction. The injection holes are coneshaped injection holes and at least two of the injection holes have different cone angles.

Abstract: A fuel injector for a fuel injection system of an internal combustion engine is described. The fuel injector has a fuel inlet connection piece for supplying fuel, a piezoelectric or magnetostrictive actuator, which is sealed off from the fuel by a seal, and a valve closing body actuatable by the actuator via a valve needle. The valve closing body working together with a valve seat surface to form a seal seat. The seal includes an inlet-side gasket, which is arranged between the fuel inlet connection piece and the actuator, and an actuator jacket that is elastically deformable in a longitudinal direction and is connected to the inlet-side gasket.

Abstract: A fuel injection valve is comprised of a nozzle plate which has at least four nozzle-hole sets. Each of the nozzle-hole sets has at least two nozzle holes through which fuel injection flows are injected and are collided with each other. The nozzle-hole sets are arranged into two aggregations so that the collided fuel injection flows are joined and are directed to two different directions.

Abstract: A valve subassembly of a fuel injector that allows spray targeting and distribution of fuel to be configured using non-angled or straight orifice having an axis parallel to a longitudinal axis of the subassembly. Metering orifices are located about the longitudinal axis and defining a first virtual circle greater than a second virtual circle defined by a projection of the sealing surface onto the metering disc so that all of the metering orifices are disposed outside the second virtual circle. The projection of the sealing surface converges at a virtual apex disposed within the metering disc. At least one channel extends between a first end and second end. The first end is disposed at a first radius from the longitudinal axis and spaced at a first distance from the metering disc.

Abstract: A fuel injection device is so constructed that fuel fed from a pressure storage chamber to a valve housing (11) with a nozzle (14) is led to a needle valve back pressure chamber (16) through a groove (21) provided on the peripheral surface of a needle valve (17); a fuel pressure in the back pressure chamber (16) is controlled by opening and closing a pressure regulating port (13) provided in the valve housing by a pilot valve (38) so as to move the needle valve, whereby the nozzle is opened and closed. The pressure regulating port is opened and closed by a drive control of the pilot valve with a valve drive unit by means of elongation and contraction of the magnetostrictive rods attributable by the action of an external magnetic field. The magnetostrictive rods, consisting of first and second magnetostrictive rods (34 and 35), are axially arranged side by side in parallel to the pilot valve.

Abstract: The invention relates to an injection device for the metered injection of two liquids, in predeterminable quantity ratios, into a reaction chamber, the device having a housing (1) that includes an injection nozzle, the opening (13) of which forms an injection valve with the valve seat (14) in the housing (1) and a valve body (15) that can be positioned on the valve seat (14); the valve body (15) can be moved by a first actuator; the collection chamber (16) of the device is associated with the nozzle opening (13), and is connected to a supply line (17) for the first liquid (A) and a supply line (21) for the second liquid (B), with a metering valve (22) being set up to block at least one supply line (21) to the collection chamber, the valve being actuated by a second actuator; one of the two liquids is under a higher pressure than the other liquid; the device further has a control device (10), which can actuate the two actuators as a function of a load-stipulated total injection quantity and as a function of a

Abstract: At an outlet portion of an injection hole (8) of a fuel injection valve (1), through removal of a part (A1, 7B) of a wall forming the injection hole (8), a restriction to a spray flow is released, thereby, a deflection spray is formed in which the spray is rich at the side of restriction released and is learn at the side of restricted, accordingly, ignition property of an internal combustion engine is improved, and an optimum spray is realized which reduces exhaust amount of unburnt gas components.

Abstract: An internal combustion engine fuel injector has a casing defining a nozzle; and a shutter pin having an axis, and housed in axially sliding manner inside the casing to close the nozzle by virtue of a control rod. The pin and the control rod are connected by a connecting device, which has an axial seat carried by the pin, and a head interposed between the axial seat and the control rod, and which engages the axial seat to transmit to the pin a resultant of forces directed solely along the pin axis.

Abstract: Fuel injector provided with a piezoelectric actuator, a valve activated by the piezoelectric actuator and regulating a fuel supply that flows in a working direction, and a mechanical transmission placed between the piezoelectric actuator and the valve; an expansion of the piezoelectric actuator displaces the valve in the working direction from a closed position to an open position in an opposite direction to that of the fuel outlet.

Abstract: A fuel injector having a piezoelectric actuator, which activates a shutter to move the shutter in a work direction between a closed position and an open position; the piezoelectric actuator is housed inside a casing having an inner chamber insulated from the fuel, and an outer surface wet by the fuel.

Abstract: A control valve configuration is described which is used in a fuel injector for internal combustion engine. The control valve contains a valve body that can be displaced axially in a valve chamber by an actuating device and is formed of two rigidly connected sections. A first section of the valve body forms a seat valve between the valve inlet and valve outlet in a first section of the valve chamber. The seat valve is closed in a rest position of the valve body and is opened in a working position of the valve body. A second section of the valve body and a second section of the valve chamber form a slide valve which, in the rest position of the valve body, produces a fluidic connection between the valve outlet and a return opening and blocks the fluidic connection between the seat valve and the valve outlets and which closes the return opening and then starts to produce a fluidic connection between the seat valve and the valve outlet only after it leaves the rest position.

Abstract: A fuel injector (1), particularly an injection valve for fuel-injection systems of internal combustion engines, has a piezoelectric or magnetostrictive actuator (16) that is arranged in a valve housing (2) and is sealed off from a fuel by an actuator housing (15), and a valve-closure member (7) which is operable by the actuator (16) with the aid of a valve needle (6) and which cooperates with a valve-seat surface (5) to form a sealing seat. The valve housing (2) and the actuator housing (15) have cut-outs (38, 39) adjoining one another, and the valve housing (2) is joined to the actuator housing (15) in an edge area of the cut-outs (38, 39). In this manner, a feed-through opening (41) is formed which is sealed off from the fuel. The feed-through opening (41) is filled with a filler element (43) by which at least one electrical supply line (37) of the actuator (16) is fixed in position in the feed-through opening (41).

Abstract: A poppet for a fuel injector having a head with one or more ducts that help reduce the formation of deposits on the head.

Abstract: A fuel injector, especially an injector for fuel injection systems in internal combustion engines, has a piezoelectric or magnetostrictive actuator. The actuator, via a valve needle, activates a valve-closure member, which cooperates with a valve seat surface to form a sealing seat. The actuator can be actuated in a first direction of motion. In contrast, the valve-closure member can be moved by the valve needle in a second direction of motion (40) that is essentially perpendicular to the first direction of motion.

Abstract: A high-pressure fuel system for internal combustion engines, having a housing that contains two high-pressure bodies. The high-pressure bodies rest with contact surfaces at least indirectly against each other and are pressed against each other by means of a tensioning device. A supply conduit is embodied in the high-pressure bodies, which carries highly pressurized fuel and passes through the contact surfaces of the two high-pressure bodies. A sealing film is disposed between the two high-pressure bodies, which encompasses the passage of the high-pressure conduit and thus assures a favorable seal.

Abstract: A fuel injector comprises a body having a longitudinal axis, a length-changing actuator that has first and second ends, a closure member coupled to the first end of the length-changing actuator, and a compensator assembly coupled the second end of the actuator. The length-changing actuator includes first and second ends. The closure member is movable between a first configuration permitting fuel injection and a second configuration preventing fuel injection. And the compensator assembly axially positions the actuator with respect to the body in response to temperature variation. The compensator assembly utilizes a configuration of at least one spring disposed between two pistons so as to reduce the use of elastomer seals to thereby reduce a slip stick effect. Also, a method of compensating for thermal expansion or contraction of the fuel injector comprises providing fuel from a fuel supply to the fuel injector; and adjusting the actuator with respect to the body in response to temperature variation.

Abstract: A fuel injector comprises a body having a longitudinal axis, an length-changing actuator that has first and second ends, a closure member coupled to the first end of the length-changing actuator, and a compensator assembly coupled the second end of the actuator. The length-changing actuator includes first and second ends. The closure member is movable between a first configuration permitting fuel injection and a second configuration preventing fuel injection. And the compensator assembly axially positions the actuator with respect to the body in response to temperature variation. The compensator assembly utilizes a configuration of at least one spring disposed between two pistons so as to reduce the use of elastomer seals to thereby reduce a slip stick effect.

Abstract: A fuel injection valve has a valve seat element having a fixed valve seat. A valve closure element coacts with the valve seat to open and close the valve. The valve seat element possesses an outer enveloping surface that is equipped with a coating made of a material other than the material of the valve seat element, or with an adhesive, by way of which a hydraulically sealed join can be achieved between the valve seat element and a valve seat support that receives the valve seat element. The fuel injection valve is suitable in particular for use in fuel injection systems of mixture-compressing spark-ignited internal combustion engines.

Abstract: An electromagnetic fuel injector comprises a body with a fuel inlet and a fuel outlet and a base that comprises a valve seat connected to the body. A moveable valve assembly comprising an armature and a valve outlet member is disposed at the fuel outlet for controlling the flow of fuel from the outlet. Positioned between the armature and valve outlet member is a dampening device that acts on the moveable valve assembly to reduce bounce of the valve outlet member at the valve seat. An electromagnetic fuel injector comprises a body with a fuel inlet and a fuel outlet and a base that comprises a valve seat connected to the body. A moveable valve assembly comprises an armature connected to a valve outlet member that includes a pintle and a ball element that is disposed at the fuel outlet to control the flow of fuel from the outlet. At least one spring, positioned between the armature and the valve outlet member, acts on the moveable valve assembly to reduce bounce of the valve outlet member at the valve seat.

Abstract: An electromagnetically actuated valve (1) has a core (5), a solenoid coil (8) and an armature that can be acted upon by the solenoid coil (8) in a stroke direction in opposition to a restoring spring (27), and a valve needle (13). The valve needle (13) is fixedly joined both to the armature (11) as well as to a valve-closure member, which cooperates with a fixed valve seat, and constitutes a movable valve element. On the valve needle (13), between the armature (11) and the valve-closure member, an auxiliary body (30) is arranged, which is movable relative to the valve needle (13). The valve needle (13) is designed as having a driving arrangement (34) such that, in response to a motion of the auxiliary body (30) in the stroke direction, the valve needle (13) can be accelerated in the same direction by energy transfer, and a rapid opening of the valve is realized.

Abstract: An injector is disclosed, in which the change in the internal pressure of each chamber is relaxed when a pressure application mechanism is reciprocating thereby to lengthen the service life of the component parts including a diaphragm portion.

Abstract: A unique variable orifice electronically controlled common variable rail injector (VOECCRI) for use in internal combustion engines characterized in part by the provision of injection ports or orifices along a tip portion of the nozzle housing having an internal cylindrical surface, and which cooperates in sealing and sliding relation with an internal hollow fuel needle having a cylindrical outer surface. In seating, the needle seats against a frusto-conical seat carried in the closure sac at the lower tip of the assembly, whereby leakage is controlled and precise opening of the injection orifices can be effected and programmed, as desired.

Abstract: At fuel downstream end of a valve body, there is arranged an injection port plate formed into a thin disc shape. In the injection port plate, there are formed four injection ports having fuel inlets in a common circumference on the center axis of the injection port plate. The injection ports are formed in the fuel injecting direction apart from the center axis of the injection port plate. In each injection port, with respect to the injection port axis joining the center of the fuel inlet and the center of the fuel outlet of each injection port, the injection port inner circumference more distant from the center axis of the injection port plate is more inclined toward the outer circumference with respect to the center axis than the injection port inner circumference less distance from the center axis of the injection port plate with respect to the injection port axis.

Abstract: A method of assembly of a fuel injector having a valve plunger reciprocable in a guide tube for movement from a closed position engaging a valve seat to an open position engaging a valve stop by energizing of a solenoid coil to move the plunger against a biasing spring, wherein the method includes setting the valve stop at a position effective to establish the desired valve stroke, and fixing the valve stop to the guide tube by first laser spot welding the valve stop in the guide tube to fix the position of the valve stop without changing the set gap, and then laser seam welding the valve stop in the guide tube at an axial location beyond the spot welds, relative to a plunger-engagable end of the valve stop, to provide a hermetic seal around the valve stop.

Abstract: A control unit for controlling a pressure buildup by a pump unit in a fuel injection system. The control unit has a control valve and a valve actuation unit connected to the control valve. The control valve is embodied as an inlet valve that opens inward in the flow direction. The control unit has a valve body that is supported so that the valve body moves axially in a housing of the control unit and rests against a valve seat of the control valve from the inside when the control valve is closed. In order to give the through flow curve of the control valve as flat a course as possible with small strokes (Ssmall) of the control valve. The control unit includes a throttle device that throttles the flow through the control valve when the control valve is open by a small stroke (Ssmall).

Abstract: A fuel injection valve for a fuel injection system of an internal combustion engines includes a valve closing body cooperating with a valve seat body to form a sealing seat, and a piezoelectric actuator for actuating the valve closing body. The piezoelectric actuator includes piezo layers and one or more temperature compensation layers. The temperature compensation layers have a temperature expansion coefficient having an operational sign opposite the sign of the temperature expansion coefficient of the piezo layers.

Abstract: An injector seat assembly for a fuel injector is provided. The injector seat assembly includes an injector seat having a longitudinal seat channel and a longitudinal channel axis extending therethrough. The injector seat is constructed from a first material. An insert is fixedly inserted into the longitudinal seat channel. The insert has a longitudinal insert channel and a longitudinal insert channel axis extending along the longitudinal seat channel axis. The insert is constructed from a second material, different from the first material. A method of constructing the injector seat assembly is also provided.

Abstract: A microdispensing system is useful for the open-jet dispensing of liquids. A valve having a valve chamber is bounded by an impermeable elastic membrane and is filled with the liquid for dispensing. One or more liquid supply lines lead to the valve chamber. An outlet closed from the exterior by the membrane in the position of rest leads from the chamber to a dispensing nozzle. An actuator chamber is disposed on the other side of the membrane. In the actuator chamber, an electromechanical drive is connected to the membrane for the purpose of briefly lifting the membrane from the outlet. The actuator chamber is closed in such manner that it can be subjected to a pressure differing from atmospheric pressure.

Abstract: A fuel injector having a fuel inlet, a fuel outlet, and a fuel passageway extending along an axis between the fuel inlet and the fuel outlet. The fuel injector includes a body having an inlet portion, an outlet portion, and a neck portion disposed between the inlet portion and the outlet portion. An adjusting tube is disposed within the neck portion of the body. A spring is disposed within the neck portion of the body, the spring having an upstream end proximate to the adjusting tube and a downstream end opposite the upstream end. A filter assembly is disposed within the tube assembly to provide a reaction member for the spring. An armature having a lower portion is disposed within the neck portion of the body and displaceable along the axis relative to the body. The downstream end of the spring is disposed proximate to the armature, the spring applying a biasing force to the armature. A valve seal is substantially rigidly connected to the lower portion of the armature.

Abstract: A fuel injector for use with an internal combustion engine. The fuel injector comprises a valve group subassembly and a coil group subassembly. The valve group subassembly includes a tube assembly having a longitudinal axis that extends between a first end and a second end; a seat that is secured at the second end of the tube assembly and that defines an opening; an armature assembly that is disposed within the tube assembly; a member that biases the armature assembly toward the seat; an adjusting tube that is disposed in the tube assembly and that engages the member for adjusting a biasing force of the member; a filter that is disposed at least within the tube assembly; an O-ring that circumscribes the first end of the tube assembly and that is maintained by the retaining portion of the filter; and a first attachment portion.

Abstract: A fuel injector having a fuel inlet, a fuel outlet, and a fuel passageway extending along an axis between the fuel inlet and the fuel outlet. The fuel injector includes a body having an inlet portion, an outlet portion, and a neck portion disposed between the inlet portion and the outlet portion. An adjusting tube is disposed within the neck portion of the body. A fuel filter is mounted inside the adjusting tube prior to the insertion of the adjusting tube into the fuel injector inlet tube. A spring is disposed within the neck portion of the body, the spring having an upstream end proximate to the adjusting tube and a downstream end opposite the upstream end. An armature having a lower portion is disposed within the neck portion of the body and displace able along the axis relative to the body. The downstream end of the spring is disposed proximate to the armature, the spring applying a biasing force to the armature. A valve seal is substantially rigidly connected to the lower portion of the armature.

Abstract: A fuel injector includes an injector body that defines a nozzle outlet. A needle valve member is mounted in the injector body and moveable a lift distance between an open position in which the nozzle outlet is open, and a closed position in which the nozzle outlet is blocked. A piezoelectric actuator is mounted in the injector body and is moveable a piezo distance between an off position and an on position. A coupling linkage interconnects the needle valve member to the piezoelectric actuator such that a movement of the piezoelectric actuator is multiplied into a larger movement of the needle valve member.

Abstract: A fuel injector comprising a valve needle engageable with a seating to control the supply of fuel to an outlet opening, comprising an adjustment member including an opening. The adjustment member is moveable to move the opening thereof relative to the outlet opening to vary the restriction to fuel flow formed by said outlet opening and, hence, the rate at which fuel is delivered by said injector.

Abstract: A high pressure gaseous fuel injector for injecting natural gas or other gaseous fuels at high pressures (eg. 300 to 700 psig more or less) into combustion engines for improved efficiency, better performance and reduced environmental emissions. The fuel injector is powered by hydraulic signals from an electrohydraulic valve. The fuel injector includes an outer cartridge housing and a universal valve cartridge mounted therein. An unsealed small clearance between the actuating piston and its bore in the cartridge allows controlled leakage of oil. The leakage of oil lubricates metal to metal contact between the upper guide and the valve and lubricates the dynamic gas seal. Gaseous fuel leakage into the leaked oil is tolerated and any combined oil/gaseous fuel is removed to an external location for separation.

Abstract: An electronically controlled micro-dispensing apparatus (10) is described. The apparatus includes a container (12), an adaptor (18), a nozzle (28) and a control circuit (34 or 42). The container is filled with the chemical (104) and propellant (102). The adaptor, nozzle and control circuit are removable from the container and are reusable. The control circuits controls the length of pulse and the time duration between each pulse. By controlling these factors, the apparatus dispenses a precise amount of liquid over a set time period. The ejector allows for controlled dispensing and allows the liquid to be sprayed a greater distance. In the preferred embodiment, the apparatus are used to dispense a pheromone in an outdoor setting, such as an orchard (100), to control insects.

Abstract: There is provided a fuel injection valve in which an operation sound at the time of an operation of the fuel injection valve is lowered, and durability of parts is improved. A flat surface 4a of a valve body 4 is provided at a lower surface side of a should portion 3a provided at a needle valve 3, and when the needle valve 3 moves in a valve closing direction, a portion B in which fuel is confined is compressed at a place between a lower surface of the shoulder portion 3a and the flat surface 4a, so that a damping effect of fluid is obtained and an operation sound is lowered.

Abstract: A fuel injection valve includes a valve seat member having a valve bore, and an injector plate coupled to an outer end face of the valve seat member. A fuel diffusion chamber is defined between the valve seat member and the injector plate. The injector plate is provided with a plurality of fuel injection bores which are parted on a plane including an axis of the valve bore into primary and secondary groups for injecting fuel toward primary and secondary intake ports. When a direction of arrangement of the primary and secondary intake ports is represented by X, and a direction perpendicular to the direction of arrangement is represented by Y, the fuel injection bores of the primary and secondary groups are formed so that they are inclined to a side opposite from the axis of the valve bore only in a direction X toward a downstream side.

Abstract: A piezoelectrically actuable fuel injector comprising an accumulator volume within which a piezoelectric stack is arranged, the accumulator volume being arranged to receive fuel from a source of pressurized fuel, in use. The piezoelectric stack carrying an end member which engages a surface associated with a piston member so as to apply a retracting force to the piston member upon a reduction in the axial length of the piezoelectric stack, the piston member being operable to control fuel pressure within a control chamber. A volume is defined between the end member and the surface associated with the piston member. The volume is provided with a vent arrangement to permit fuel within the volume to flow to a low pressure drain.