Abstract: The present invention relates to an injection device having an injection valve (12), a valve device (18, 20) for controlling the injection, and a setting element (22) for operating the valve device (18, 20), the valve device having at least one first valve (18) and a second valve (20) which can be operated by the settling element (22) via a common hydraulic coupling space (24). The present invention further relates to a method for injecting fluid in which a setting element is (22) is activated, a valve device (18, 20) is operated by the setting element (22), and an injection valve (12) is opened, the first valve (18) and a second valve (20) of the valve device (18, 20) being operated by the setting element (22) via a common hydraulic coupling space.

Abstract: A fuel injection system having a high-pressure source and an injection valve having a pressure chamber communicating with the high-pressure source, and a valve member controlling at least one injection opening when acted upon by the pressure in the pressure chamber in an opening direction counter to a closing force. A control piston movable with the valve member in the closing direction defines a control pressure chamber which communicates with the high-pressure source and which has a communication controlled by an electrically actuated valve, with a relief chamber. The control valve is opened for fuel injection, so that the control pressure chamber communicates with the relief chamber. The valve member and the control piston move in the opening direction when the control valve is opened, and a limitation in the opening motion of the injection valve member and of the control piston is effected only by a pressure increase in the control pressure chamber from closure of the control valve.

Abstract: in a fuel injection valve having a valve body, having a control pressure chamber that is disposed inside the valve body and is closed at one end by an actuating part, which is for an injector needle and can be moved in the control pressure chamber between a closed position and an open position, having an inlet into the control pressure chamber, and having an outlet from the control pressure chamber that is controlled by a control valve, the opening speed of the injector needle should be increased. To this end, the mouth opening of the inlet into the control pressure chamber is disposed so that it is at least partially closed by the actuating part when the actuating part moves from the closed position into the open position.

Abstract: The invention relates to an injector with a valve chamber which is contained in an injector housing and can be loaded by way of an inlet from the high-pressure accumulation chamber. This valve chamber loads a nozzle inlet to an injection nozzle by means of a control element that can be moved in the injector housing upon the pressure relief of a control chamber. On the control element, which is embodied of one part or multiple parts, a control surface is disposed in the pressure relief region of the nozzle inlet.

Abstract: A fuel injection valve with a valve member (10), which cooperates with a valve seat (16) to control injection openings (20). The valve member (10) is guided, in a portion remote from the combustion chamber, in a bore (7) and is surrounded by a pressure chamber (12), which can be filled with fuel at high pressure. The valve member (10) is urged by a spring (27) disposed in a spring chamber (25) and having a closing force in the direction of the valve seat (16), and in an appropriate opening pressure in the pressure chamber (12), as a result of the hydraulic pressure on a pressure shoulder (11), embodied on the valve member (10), the valve member lifts from the valve seat (10) and thus opens the injection openings; the injection of the fuel is effected separately in a main injection and a subsequent postinjection.

Abstract: In a fuel injection nozzle for an internal combustion engine, a frictional force reducing member is interposed between a seating surface of a shoulder portion of a nozzle body and an inner seating surface of a bearing portion of a retaining nut, whereby a frictional force developed between both seating surfaces and can be diminished without performing a high-degree of surface machining on the inner seating surface of a bearing portion of the retaining nut, even if the surface roughness of the inner seating surface of a bearing portion of the retaining nut is large. Consequently, it is possible to prevent deformation of a slide portion of the nozzle needle which is attributable to a twist of the nozzle body caused by frictional force.

Abstract: A fuel injector unit comprises a follower assembly that includes a sleeve having an internal groove that receives a spring clip. The clip is made with a spring ring stock having a diameter less then the width of the groove so that the sleeve may be freely rotated around the retainer clip held in the groove. The retainer clip has linear portions aligned along the flat walls of a follower subassembly that receives a plunger carried by the follower assembly. The flat walls terminate at an expanded shoulder that limits displacement of the retainer clip to a fixed height of the follower assembly for shipping and handling, while permitting controlled axial movement of the follower assembly and the plunger along the aligned flat surfaces of the follower subassembly.

Abstract: Disclosed is an injector for fuel injection, with a magnet valve for controlling an injection valve, in which the magnet valve has a movable armature that can be moved onto a valve seat in the lower armature chamber. The lower armature chamber communicates fluidically with the control pressure chamber of the injection valve via bores. Via a return bore, incidental leak fuel quantities can be returned to a tank via the lower armature chamber. To prevent armature recoil upon closure of the valve seat by the armature, it is proposed that means be provided in the injector for reducing pressure fluctuations occurring in the lower armature chamber. Eliminating pressure fluctuations in the lower armature chamber leads to maximal elimination of armature recoil.

Abstract: A fuel injector having a fuel flow rate set by injector stroke is disclosed. The fuel injector includes a housing having a hollow passage and a seat disposed at one end of the hollow passage. A needle is slidably mounted in the hollow passage. The needle is operable between a first position wherein the needle engages the seat and a second position wherein the needle is disposed away from the seat. A first flow area is formed by a minimum frusto-conical area between the seat and the needle when the needle is disposed away from the seat. The fuel injector also includes an opening at the one end of the hollow passage proximate to the seat. The opening has a second flow area larger than the first flow area. A method for setting a gaseous fuel injector flow rate with injector stroke is also disclosed.

Abstract: A control apparatus for a unit fuel injector, the injector internally preparing fuel during an injection event at a pressure sufficient for injection into an internal combustion engine by means of an intensifier piston includes a selectively actuatable controller being in fluid communication with a source of pressurized actuating fluid and being in fluid communication with a substantially ambient actuating fluid reservoir, the controller having a first valve for selectively independently porting actuating fluid to and venting actuating fluid from the intensifier piston and a second valve for selectively independently porting actuating fluid to and venting actuating fluid from a needle valve during the injection event for controlling opening and closing of the needle valve. The control apparatus may also control an engine intake/exhaust valve. An engine valve actuator and methods of control are further included.

Abstract: A flow controller assembly for use with a hydraulically-actuated, electrically-controlled fuel injector, includes a flow controller fluidly disposable intermediate an injector control valve assembly and an injector intensifier assembly for controlling flow of actuating fluid to and from the intensifier assembly to effect rate shaping of an injectable quantity of fuel and to effect a reduction of noise generated by the stopping of return motion of an intensifier piston. A fuel injector and a method of controlling an intensifier piston are also included.

Abstract: The fuel injector includes a solid state actuator that operates through an actuator motion amplifying lever to directly control the needle valve motion. Hydraulic forces, which act along the axes of the needle valve and the motion amplifying lever, are compensated by using a control piston, or other biasing means, to reduce the required amplitude of the control current/voltage and to reduce the required strength of the spring biasing the needle valve closed. The fuel injector may also include a control fuel inlet that is separate from the injection fuel inlet port.

Abstract: A fuel injection system having a high-pressure fuel pump and a fuel injection valve for each engine cylinder. A pump work chamber can be made to communicate with a pressure chamber of the injection valve having a valve member movable by pressure in the pressure chamber to control opening of at least one injection opening. A connection of the pump with a relief chamber is controlled by a first electrically actuated control valve, and a second control valve controls the pressure in a control pressure chamber, which pressure urges the injection valve in the closing direction. A blocking valve is disposed in the connection of the pump with the pressure chamber, and the connection of the pump with the relief chamber, in which the first control valve is disposed, leads away between the pump and the blocking valve.

Abstract: A pressure-controlled injector for injection systems for injecting fuel that is at high pressure into combustion chambers of internal combustion engines. A 3/2-way valve body is provided, which communicates with an inlet for fuel from a high-pressure collection chamber (common rail). The nozzle chamber of a nozzle needle can also be acted upon by fuel at high pressure. The stroke motion of the nozzle needle can be achieved via a hydraulic control chamber that can be pressure-relieved via a control line that has an externally actuatable control element.

Abstract: An electronically-controlled fuel injector includes a pressurized fluid chamber that communicates high pressure fluid to first and second pressure control chambers. A direct-operated check moves between closed and open positions in response to a difference in fluid pressure in the first and second pressure control chambers. A thermally pre-stressed bender actuator is used to operate a control valve that controls the fluid pressure in the first pressure control chamber to effectively control opening and closing of the check during portions of an injection sequence.

Abstract: The invention relates to a fuel injector which includes a hydraulic booster which can be made to communicate on the high-pressure side with an inlet from a high-pressure source. Between a high-pressure side and a system pressure side, there is a throttle restriction. A throttle element that can be acted upon by pressure from the high-pressure side and that is associated with an outflow opening is received movably in a hollow chamber of the injector body and closes a sealing gap that lengthens a sealing length.

Abstract: A reverse flow valve member is positioned within an injector body of a fuel injector and is movable between a closed position and an open position. When the reverse flow valve member is in its closed position, an upper portion of a nozzle supply passage is blocked from fluid communication with a lower portion of the nozzle supply passage. A compressed spring biases the reverse flow valve member to its closed position. When the reverse flow valve member is in its open position, the fuel pressurization chamber is fluidly connected to the lower portion of the nozzle supply passage. The present invention limits gas ingestion due to tip leakage, and allows an injector with trapped gas to prime itself.

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 fuel injector has a fuel inlet, and a metering valve which is activated by an electromagnetic actuator to open and close an injection nozzle; the metering valve has a control chamber communicating with the inlet and defined by an end wall, in which is formed an outlet hole closed by a shutter moved along an axis by the actuator; the end wall and the shutter are defined by respective parallel, facing surfaces which rest against each other to compress the film of fuel issuing from the hole during closure by the shutter, and which have channeling formed about the hole to generate, in use, a counterpressure for the outflowing fuel.

Abstract: For each cylinder of the internal combustion engine, the fuel injection apparatus has a high-pressure fuel pump and a fuel injection valve connected to it. A pump piston of the high-pressure fuel pump defines a pump working chamber, which is connected to a pressure chamber of the fuel injection valve, which has an injection valve member, which controls the injection openings and which the pressure prevailing in the pressure chamber can move in an opening direction, counter to a closing force. A first control valve controls a connection between the pump working chamber and a relief chamber, and a second control valve controls a connection between a relief chamber and a control pressure chamber connected to the pump working chamber. A control piston, which is connected to the injection valve member, divides the control pressure chamber into two separate partial chambers, which are connected to each other by means of a throttle restriction.

Abstract: The injector has a control rod controlled by the fuel pressure in a control chamber, and a nozzle having an injection chamber supplied with pressurized fuel for injection. The nozzle has at least one injection orifice normally closed by a pin connected to the rod and activated by the fuel pressure in the injection chamber. The control chamber has a pressurized-fuel intake conduit, and a fuel discharge conduit which is normally closed and is opened for a variable length of time depending on the amount of fuel to be injected. The pin and the rod, and/or the intake conduit and the discharge conduit, are so sized as to keep the pin and the rod hydraulically balanced in the maximum-lift position to open the orifice.

Abstract: The invention relates to a common rail injector for the injection of fuel in a common rail injection system of an internal combustion engine, which has an injector housing with a fuel inlet that communicates with a central high-pressure reservoir outside the injector housing and communicates with a pressure chamber inside the injector housing, from which highly pressurized fuel is injected depending on the position of a control valve, which assures that a nozzle needle, which can move axially back and forth in a longitudinal bore in the injector housing counter to the initial stress of a nozzle spring, lifts up from a seat when the pressure in the pressure chamber is greater than the pressure in a control chamber, which can be connected via an inlet throttle to the fuel inlet and can be connected via an outlet throttle to a relief chamber, and in order to produce a common rail injector which is simple in design and inexpensive to produce, the connection between the fuel inlet and the pressure chamber is dispo

Abstract: In a fuel injection nozzle, a nozzle body is provided inside with a guide hole having a second guide portion (cylindrical hole) for slidably holding a guide shaft of a needle and a seat surface axially below the second guide portion, with first injection bores opened to the seat surface and with second injection bores opened to an inner circumference of the second portion. The needle is provided at an end thereof with a circular seat contact coming in contact with the seat surface axially above the first injection bores and inside the guide shaft with a fuel passage through which fuel is supplied to a position axially above the seat contact. With the construction mentioned above, as the second guide portion is formed axially above the sack chamber and inner diameter thereof is larger than that of the sack chamber, the second guide portion is more easily formed at lower cost.

Abstract: An electromagnetic actuator for a control valve module in an engine fuel injector, the module being a replaceable, independent element of the injector. The actuator has a stator with electromagnetic coil windings on a bobbin located within the control valve module. An armature is connected to a control valve in the module. The bobbin supports and precisely positions connector pins for the coil windings for registry with an external electrical wire harness.

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 invention relates to an injector body for a fuel injection system, in which the injector body has a substantially cylindrically shaped valve chamber, into which fuel can be introduced at high pressure via an inlet bore, which discharges through an inlet opening in the valve chamber. To compensate for the high local notch tensile stresses in the circumferential direction of the valve chamber, it is proposed that at least in the region of the inlet opening, the valve chamber be provided with bulges, each adjacent the inlet opening in the circumferential direction. These bulges bring about a major compensation for the notch tensile stresses and thus increase the high-pressure strength.

Abstract: An injector for an injection system of an internal combustion engine, with an injector head (1), a nozzle (13) for injecting fuel, a control unit (12) for controlling the transfer of fuel from the injector head (1) to the nozzle (13) and an actuator (6) for the mechanical activation of the control unit (12) in order to control fuel injection, an injector housing (2), which receives at least the control unit (12), being integrally formed on the injector head (1) at the bottom.

Abstract: A closed needle injector assembly and method are provided which effectively extending injection duration and improving fueling accuracy at part load conditions, providing a low quantity detached pilot injection at all operating conditions and controlling the duration of, and dwell time between, the pilot injection and one or more higher flow rate primary injections independent of fuel injection pressure. The closed needle injector assembly includes first and second needle valve elements, respective control volumes and a single injection control valve to control the movement of the needle valve elements. A sequencing device is mounted on the injector to permit movement of only the inner needle valve element to define a low fuel injection rate event and permit selectively, controlled movement of both the inner and outer needle valve elements to open positions to define a subsequent primary fuel injection event.

Abstract: An improved closed nozzle injector assembly for injecting high pressure fuel into the combustion chamber of an engine is provided which includes a first needle valve element associated with a first set of injector orifices, a first needle valve control device for controlling the opening and closing of the first needle valve, a second needle valve associated with a second set of injector orifices and a second needle valve control device for controlling the opening and closing of the second needle valve. Each needle valve control device includes a control volume positioned at one end of the respective needle valve, a control volume charge circuit for supplying high pressure fuel to the respective control volume and the respective injection control valve for controlling the flow of high pressure fuel from the respective control volume to a low pressure drain thereby controlling the movement of the respective needle valve.

Abstract: In some hydraulically actuated fuel injectors, a pressure communication passage extends from a pilot valve to the underside of a spool valve to control movement of the same. For the spool valve to move, a substantial amount of fluid flow past the pilot valve is required due to the relatively large amount of fluid that must be displaced by movement of the spool valve member. However, during cold start, when the oil in the pressure communication passage is relatively viscous, it is difficult to move enough fluid past the relatively small flow area through the pilot valve to allow the spool valve to advance to its upper position. Therefore, the fuel injector of the present invention includes a pressure communication passage that is connected to the underside of the spool valve to be separated from the branch that passes through the pilot valve.

Abstract: An ultrasonic fuel injector for injecting a pressurized liquid fuel into the combustion chamber of an internal combustion engine that uses an overhead cam for actuating the injector includes a valve body having an injector needle disposed therein forming a needle valve to meter the flow of fuel through the injector. The valve body is formed of ceramic material that is transparent to magnetic fields changing at ultrasonic frequencies. The injector needle includes a magnetostrictive portion disposed in the region of the valve body that is surrounded by a wire coil wound around the outside surface of the ceramic valve body. The wire coil is connected to a source of electric power that oscillates at ultrasonic frequencies. A sensor is configured to signal when the overhead cam is actuating the injector to inject fuel into the combustion chamber of the engine.

Abstract: A control valve (15) for injectors of injection systems for internal combustion engines is proposed, in which part of the displacement path of the final control element (45) serves the purpose of pressure elevation in the control chamber (11). The closing times of the nozzle needle (19) are thereby reduced.

Abstract: The control space of the fuel injection valve is delimited, on the one hand, by the piston of the injection-valve member, on the other hand by the slide-valve body and circumferentially by the sleeve. Both the double-acting piston and the slide-valve body are guided in a narrow sliding fit on the sleeve. The throttle passage runs through the slide-valve body and is flow-connected permanently to the control passage in the control body. The throttle inlet leads from the high-pressure space into the control passage. The latter, on the side facing away from the slide-valve body, can, via a pilot valve, be connected to a low-pressure space and be separated again from the latter. The connection of the control passage to the low-pressure space leads to a pressure drop in the control space, with the result being that the injection-valve member moves in the direction of the slide-valve body and releases the injection nozzles.

Abstract: The injector has an injector body having a seat for a metering valve in turn having a control chamber for controlling a control rod. The control chamber has an inlet conduit and a drain conduit controlled by a shutter, and is defined by two parts, one of which is defined by a bush having a through opening for guiding the control rod, and the other of which is defined by a plug member for closing the control chamber. The inlet conduit is located on the bush, and the drain conduit on the plug member. The bush is of such a diameter as to interfere slightly with at least one cylindrical portion of the seat, and is driven in fluidtight manner inside the seat so that an end edge rests on a shoulder of the seat. The plug member is fixed in fluidtight manner to the opposite end of the bush by means of a ring nut having a projection which acts along the centerline of the thickness of the bush.

Abstract: An injector for a common rail fuel injection system in which the opening of the nozzle needle is done under pressure control, while the nozzle needle is compulsorily closed when the control valve closes. This has advantages with regard to the onset of injection and the closing of the nozzle needle.

Abstract: The invention relates to an injector for injecting fuel that is at high pressure into the combustion chambers of an internal combustion engine. A control part (4) which is movable up and down by actuator actuation is received in a bore (3) in the housing (2) of the injector (1). By means of the actuator, the control part (4) is movable into a position that enables the fuel delivery into a nozzle inlet (10, 11). The valve chamber (8, 38) in the housing (2) of the injector (1) can be opened and closed during the injection phases (41, 42) by control edges (36, 37) toward the control part, while the pressure relief of the injection system (11, 12, 34) is effected via slide portions (13, 21) disposed on the control part (4).

Abstract: A metering device and method for delivering fluid that employs a compensating element. The metering device has a housing defining a fluid chamber that contains a pressurized fluid. The-housing further encloses an actuating drive, a valve needle and a compensating element. The housing terminates at a housing opening for delivery of fluid to the outside of the housing. Fluid is delivered from the housing by moving the actuating drive which in turn displaces the valve needle in an opening direction. Upon displacement of the valve needle, the valve needle moves axially in the opening direction with little, if any, lift loss due to the compensating element. The compensating element further acts to compensate for shifting or movement of metering components due to external factors, such as varying thermal loads, aging effects, and settling effects.

Abstract: In a fuel injection valve for a pump-line-injector system of an internal combustion engine, comprising a fuel injector with a nozzle body, a nozzle needle longitudinally movably supported in the nozzle body between a seated nozzle closing position and a lift-off position assumed during fuel injection, the nozzle includes a fuel supply passage, a fuel drain passage, a connecting passage extending from the fuel supply passage to the fuel drain passage, and a spring-loaded pressure relief piston forming a control valve disposed in the path of the pressurized fuel from the fuel supply passage to the drain passage for controlling the pressure of the fuel supplied to the nozzle needle during fuel injection into a cylinder of the internal combustion engine.

Abstract: The fuel injection valve (16) has an injection valve member (24), by which at least one injection opening (26) is controlled. The motion of the injection valve member (24) is varied by a control valve (18) that has a control valve member (54) by which the pressure in a control pressure chamber (50) is controlled in that the control valve member controls a relief chamber (46) in a closing piston (42) that defines the control pressure chamber (50) and that by means of the pressure prevailing in the control pressure chamber (50) urges the injection valve member (24) in its closing direction. The control valve member (54) is displaceable via a hydraulic boost by a piezoelectric actuator (78), as a result of which the piezoelectric actuator opens or closes the relief chamber (46).

Abstract: The present invention finds application in engines using mechanically actuated electronically controlled fuel injectors having direct control needle valves. In valves such as these, a spill control valve member controls fuel pressurization within the injector while a needle control valve member controls the timing and duration of the injection event. However, when the momentum of fuel exiting the fuel injector past the spill valve is greater than that of the tappet and plunger moving toward their downward positions, engine components upstream of the tappet can briefly separate and re-engage, which can result in increased mechanical noise levels. Therefore, the present invention is directed to maintaining sufficient contact force in the various engine components to reduce the mechanical noise levels by positioning a flow restriction between the fuel pressurization chamber of the fuel injector and a fuel source.

Abstract: An apparatus and method for causing a fuel injector to overcome its inherent fuel injection pressure threshold long enough to completely inject a predetermined volume of fuel during each fuel shot associated with a particular fuel injection event. The fuel injector is in electrical communication with an electronic controller for receiving control signals of pre-calculated timing and duration therefrom. Furthermore, the fuel injector is in mechanical communication with a cam follower. A camshaft has a cam profile in mechanical communication with the cam follower, the cam profile including at least one lobe operable to generate pressure within the fuel injector sufficient to overcome the fuel injection pressure threshold in predetermined intervals in conjunction with the control signal of the electronic controller.

Abstract: In a fuel injector for internal combustion engines having a valve housing, having an axially movable valve element for opening and closing an injection opening, and having a drive rod that operates in the closing direction of the valve element, the drive rod being guided in a bore hole of a valve piece that is inserted into the valve housing, and enclosing in the valve piece a control pressure chamber, which can be connected, via an intake channel that radially branches off from the control pressure chamber and that is provided with at least one intake throttle, to a high-pressure fuel connection, and that can be connected, via an outlet channel having an outlet throttle and being able to be closed by a control valve element, to a low-pressure fuel connection, in order to be able to set the fuel flow through the intake throttle, it is proposed that, in a through hole of the valve housing running radially with respect to the axis of the bore hole, a control element is arranged that can be fixed in position and

Abstract: The invention relates to a metering valve for controlling the delivery of fuel from a high-pressure fuel line (1) to an injection nozzle (6) of an internal combustion engine, having one connection for the high-pressure fuel line (2), one connection for the injection nozzle (6), and one connection for a leak fuel line (13).

Abstract: An EMD-type injector is provided with a spring seat in which the juncture between the head and the stem of the spring seat is formed as an undercut groove within specified shape parameters.

Abstract: A closed needle injector assembly and method are provided which effectively extending injection duration and improving fueling accuracy at part load conditions, providing a low quantity detached pilot injection at all operating conditions and controlling the duration of, and dwell time between, the pilot injection and one or more higher flow rate primary injections independent of fuel injection pressure. The closed needle injector assembly includes first and second needle valve elements, respective control volumes and a single injection control valve to control the movement of the needle valve elements. A sequencing device is mounted on the injector to permit movement of only the inner needle valve element to define a low fuel injection rate event and permit selectively, controlled movement of both the inner and outer needle valve elements to open positions to define a subsequent primary fuel injection event.

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: Process for the introduction of liquid into a continuous process for the gas-phase polymerization of a olefin monomer and one or more other alpha-olefins in a fluidized-bed reactor, the liquid being introduced by at least one nozzle having a feed pipe and a sleeve sliding inside and at the end of the pipe, the position of the said sleeve along the feed pipe being determined by the pressure of the feed liquid and the return force of a preloaded spring, the spring having one end fixed to the sleeve and the other end to the feed pipe, the sleeve being provided with one or more recesses along its surface for sliding with the feed pipe, the recesses emerging in a groove around the circumference of the sleeve and below a circular stop integral with the same sleeve, the stop resting, when the nozzle is not in use, on a rim of the end of the feed pipe, the rim and the circular stop of the sleeve each being provided with a bearing surface, the contact area of which is minimized to allow good sealing.

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: The fuel injection device has a fuel pump for each cylinder of the engine, which fuel pump has a pump piston that is driven into a stroke motion by the engine and delimits a pump working chamber, which is supplied with fuel from a fuel tank and is connected to a fuel injection valve, which has an injection valve member that controls at least one injection opening and can be moved by the pressure generated in the pump working chamber in an opening direction counter to a closing force. A first electrically controlled control valve controls a connection of the pump working chamber to a discharge chamber, and a second electrically controlled control valve controls the pressure prevailing in a control pressure chamber of the fuel injection valve, which pressure acts at least indirectly on the injection valve member in the closing direction.

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.