Abstract: A fuel injector is disclosed. The fuel injector may have an injector body having a fuel inlet and at least one orifice. The fuel injector may also have a first check valve member. The first check valve member may be selectively movable to fluidly block a first flow of fuel from the fuel inlet to the at least one orifice. The fuel injector may have a second check valve member. The second check valve member may be selectively movable to fluidly block a second flow of fuel from the fuel inlet to the at least one orifice. The fuel injector may also have a control valve assembly. The control valve assembly may be configured to selectively operate either the first check valve or both the first check valve and the second check valve to fluidly connect the fuel inlet and the at least one orifice.

Abstract: An electromagnetic actuator includes a fixed body, a moving part forming a magnetic core of the actuator and being movable in translation with respect to the fixed body between a retracted position and a deployed position, a magnetic piece forming a permanent magnet adjusted to generate a first magnetic force holding the moving part in the retracted position, and a coil adjusted to engender a second magnetic force opposed to the first magnetic force when the coil is supplied with an electrical excitation current. The moving part includes one or more notches formed in a body of the moving part.

Abstract: A fuel injector and method are disclosed wherein an injector body defines a cavity and passages from an inlet at the cavity through an outside surface of the injector body. Each passage may have a first inner contour at a first angle and a second inner contour at a second angle. An injector pin with a fuel pass-though volume may be movable within the cavity to selectively overlap an outlet of the pass-through volume with an inlet of the passages to selectively direct fuel in varying quantities along the first second inner contours.

Abstract: A fuel system for an internal combustion engine includes a common rail and a plurality of fuel injectors connected to the common rail and each including an outlet check, an injection control valve, and an injection rate controller. The injection rate controller varies a flow area to a nozzle of the fuel injector such that a pressure drop through the fuel injector is varied to provide injection rate shaping.

Abstract: A gas injection valve includes a poppet valve extending from a valve body having a valve seat, a plunger moveable within a plunger body, a plunger stop axially moveable within a plunger stop enclosure formed within a plunger stop body secured within the valve body adjacent to the plunger body, a plunger follower secured to and extending through the plunger stop and in contact with the poppet valve, and a port for receiving hydraulic fluid extending through the valve body into the plunger stop body enclosure. The plunger stop is moveable between a first position and a second position. The gas injection valve has a first stroke length when the plunger stop is in the first position and a second stroke length when the plunger stop is in the second position.

Abstract: An injector, including: a moveable armature having a bore and upper and lower control surfaces; a lower housing including a bore and upper and lower stationary control surfaces; and a flow geometry defined along an exterior of the armature. The armature includes a transverse flow path fluidly coupled with the armature bore and the flow geometry. The lower housing includes a transverse flow path fluidly coupled with the lower housing bore. Upon moving the armature from a first position to a second position, a first flow path is formed between the flow geometry and the lower housing transverse flow geometry through a space between the lower stationary control surface and the lower armature control surface, and a second flow path is formed between the armature bore and the lower housing transverse flow geometry through a space between the upper stationary control surface and the armature upper control surface.

Abstract: A jetting device and/or fluid module include a module body defining a passageway extending through the module body and also partially defining a fluid chamber, a nozzle supported by the module body, a valve element at least partially within the fluid chamber, a biasing element contacting the valve element and also contacting the module body, and a sealing member contacting the periphery of the valve element and configured to partially define the fluid chamber. The nozzle defines a fluid outlet that is in fluid communication with the fluid chamber. The valve element has an upper portion outside of the fluid chamber that is adapted for contact with the drive pin, and the biasing element is configured to apply a spring force to the valve element. The valve element is configured to cause a droplet of the fluid to be jetted from the fluid outlet when the valve element is moved in the direction toward the nozzle.

Abstract: A solenoid valve provided with a valve element that abuts against and separates from a valve seat to seal fuel; a movable iron core capable of being separated from the valve element; and a fixed iron core arranged opposed to the movable iron core. The solenoid valve also includes: a first spring member that energizes the valve element toward a side of the valve seat; a second spring member that energizes the movable iron core toward the fixed iron core; and a stopper part disposed on the side of the valve seat with respect to the movable iron core, and arranged with the movable iron core via a gap in a displacement direction in a valve closed state. The gap is set so the movable iron core collides with the stopper part when being displaced in the valve closing direction after the valve element is opened.

Abstract: A fuel injector is provided and may include an injector body and an injector valve. The injector body may define a longitudinally extending chamber and may include a first intake port, a second intake port and a fuel injection port. The injector valve may be disposed within the chamber and may include a longitudinally extending aperture in fluid communication with the longitudinally extending chamber. The injector valve may be configured to prevent fluid communication between the first intake port and the second intake port, and may be configured to prevent fluid communication between the fuel injection port and the second intake port.

Abstract: The housing (18) of the fuel injection valve (10) of the device for intermittently injecting fuel into the combustion chamber of an internal combustion engine comprises a high-pressure inlet (34) with a conical sealing face (44). The high-pressure chamber (36) is disposed in the housing (18) from the high-pressure inlet (34). A cartridge-like, independent component (56) is inserted into the high-pressure chamber (36). Said component comprises the valve carrier (46), the non-return valve (48), the holding element (50), and preferably the filter body (52?). The valve carrier (46) is provided with a conical outer sealing face (69), by which the valve carrier rests against the conical sealing face (44). A fixing element (74) presses the supply line (16) against the valve carrier (46).

Abstract: The invention relates to a fuel injection valve comprising a housing (1) in which pressure is applied to a nozzle needle (8), in a control chamber (28), at least indirectly with a closing force in the direction of a valve seat (10). The pressure in the control chamber (28) can be adjusted using a control valve (40) as said control chamber (28) is able to be connected to a low pressure chamber (46) via an outlet restrictor (31) and be filled with fuel at high pressure via an inlet restrictor (30). A longitudinally-displaceable control piston (29) is arranged in the control chamber (28) and divides said chamber (28) into a first control sub-chamber and a second control sub-chamber (228), the first control sub-chamber (128) being able to be connected to the low pressure chamber (46) by means of said outlet restrictor (31).

Abstract: An electromagnetic fuel injection valve includes: a valve element which closes a fuel passage by coming into contact with a valve seat and opens the fuel passage by going away from the valve seat; an electromagnet which includes a coil and a magnetic core formed as a drive portion for driving the valve element; a movable element which is held by the valve element in a state where the movable element is displaceable in the direction of a drive force of the valve element relative to the valve element; a first biasing portion for biasing the valve element in the direction opposite to the direction of a drive force generated by the drive portion; a second biasing portion for biasing the movable element in the direction of the drive force with a biasing force smaller than the biasing force generated by the first biasing portion; and a restricting portion for restricting the displacement of the movable element in the direction of the drive force relative to the valve element.

Abstract: An internal combustion engine includes a cylinder with a combustion chamber and a piston selectively changing the volume of the combustion chamber. The combustion chamber receives a mixture of air, hydrogen and a liquid fuel consisting essentially of water and a flammable, preferably non-fossil, substance. The contents of the combustion chamber are ignited generating power.

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: A common rail fuel injector includes a needle valve member that moves to open and close nozzle outlets for a fuel injection event responsive to pressure in a needle control chamber. Between injection events, the needle control chamber is fluidly connected to the fuel inlet by a first pathway that includes a Z orifice, and fluidly connected to the fuel inlet by a second pathway that includes an F orifice, an intermediate chamber and an A orifice. During an injection event, the needle control chamber is fluidly connected to a drain outlet by a third pathway that includes the A orifice, the intermediate chamber an E orifice and a buffer chamber, which may assist in avoiding cavitation erosion in a sensitive area associated with a flat control valve seat. Different performance characteristics are achieved by adjusting the sizes of the respective of F, A, Z and E orifices.

Abstract: Method and apparatus for controlling needle seat load in very high pressure diesel injectors. In accordance with the method, a needle control piston responsive to hydraulic forces for controllably forcing the injector needle against the needle seat is provided, as is a stop for the needle control piston to limit the needle control piston movement toward the needle seat. This provides a stop for the needle control piston, so that the compressive deflection between the needle control piston and the needle seat limits the force of the injector needle on the needle seat against increasing hydraulic forces on the needle control piston once the needle control piston reaches the needle control piston seat.

Abstract: A common rail fuel injector includes a needle valve member that moves to open and close nozzle outlets for a fuel injection event responsive to pressure in a needle control chamber. Between injection events, the needle control chamber is fluidly connected to the fuel inlet by a first pathway that includes a Z orifice, and fluidly connected to the fuel inlet by a second pathway that includes an F orifice, an intermediate chamber and an A orifice. During an injection event, the needle control chamber is fluidly connected to a drain outlet by a third pathway that includes the A orifice, the intermediate chamber and an E orifice. Different performance characteristics are achieved by adjusting the sizes of the respective of F, A, Z and E orifices.

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: Oil intensified common rail injectors that combine a common-rail non-intensified injector with an oil-intensified injector. The invention also uses fuel (common rail) pumps that are commercially available since the injector does not rely on this pump for intensification function. Also, since the pressure of the fuel pump is limited to lower than the intensified pressure, the injected pressure is limited to the unit injector; this eases the rail and tube requirements to this lower fuel rail pressure. The injector operates up to this limited pressure with no intensification. Also a separate oil system is configured to operate a hydraulic intensifier. Thus the system is able to achieve very high injection pressure without common rail pump, rail, fitting and jumper tube limits. The oil system does not need to operate or run unless these elevated pressures are required. Embodiments using direct needle control are disclosed.

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 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 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: 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.

Abstract: A gasoline unit injector includes a high speed, high force actuator such as a magnetrostrictive or piezoelectric actuator. The actuator operates a positive displacement diaphragm pump. The pumping volume is isolated from a supply rail by an inlet check valve, and is isolated from the engine manifold by an outlet check valve. Each of the check valves includes a disk having a central anchor and a peripheral valve seat. Diaphragm movement reduces pump volume and thereby displaces fuel at high pressure through outlet valve. Fuel spray is formed by geometry of outlet valve, the frequency of actuation, and mass and pressure of the displaced fuel. Relaxation of actuator, and therefore diaphragm, increases pump volume and thereby draws fuel into pump volume through the check valve.

Abstract: Fuel injectors with boosted needle control providing controlled and rapid needle closure. Boost and drive pistons are provided for hydraulic actuation to controllably close the needle, with the boost piston reaching a mechanical stop before the needle reaches the closed position, with the drive piston alone providing adequate hydraulic force to hold the needle closed. In a preferred embodiment, fuel from the intensifier is coupled to the top of the boost and drive pistons to close the needle, and controllably coupled to the bottom of the boost and drive pistons to allow pressure in the needle chamber to open the needle. Apparatus for control of fuel pressure to the bottom of the boost and drive pistons is disclosed.

Abstract: A fuel injection valve includes a valve chamber, a control valve, an actuator, a control chamber, and a nozzle. The control valve is provided in the valve chamber. The actuator actuates the control valve. The control chamber is always communicated with the valve chamber through a communication passage. The nozzle has a needle for opening and closing an injection orifice, wherein the needle is biased in a valve closing direction for closing the injection orifice by pressure of fuel in the control chamber. High pressure fuel in a high-pressure fuel passage is introduced into the control chamber only through the communication passage in a state, where communication between the valve chamber and the high-pressure fuel passage is allowed by the control valve. The communication passage has a common orifice.

Abstract: Fuel injectors with boosted needle control providing controlled and rapid needle closure. Boost and drive pistons are provided for hydraulic actuation to controllably close the needle, with the boost piston reaching a mechanical stop before the needle reaches the closed position, with the drive piston alone providing adequate hydraulic force to hold the needle closed. In a preferred embodiment, fuel from the intensifier is coupled to the top of the boost and drive pistons to close the needle, and controllably coupled to the bottom of the boost and drive pistons to allow pressure in the needle chamber to open the needle. Apparatus for control of fuel pressure to the bottom of the boost and drive pistons is disclosed.

Abstract: An injection nozzle for use in delivering fuel to an internal combustion engine includes an outer valve (24) which is engageable with an outer valve seat (38) so as to control fuel delivery into the engine through a first nozzle outlet (26) and an inner valve (32) which is slidable within a bore (30; 130) provided in the outer valve (24) and engageable with an inner valve seat (40) so as to control fuel delivery into the engine through a second nozzle outlet (28).

Abstract: A fuel injection device of an internal combustion engine includes a piezoelectric actuator and a valve element that are coupled to one another. The valve element has a pressure stage. An increase in the force acting on the piezoelectric actuator is interpreted as an actual opening of the valve element, and/or a decrease in the force acting on the piezoelectric actuator is interpreted as an actual closing of the valve element, and that these be taken into account at least part of the time in the controlling of the piezoelectric actuator.

Abstract: A fuel injection valve includes a main body having a nozzle hole and a compression chamber. The main body accommodates a compression unit for pressurizing fuel accumulated in the compression chamber. The fuel injection valve further includes a valve element being axially movable in the main body. The valve element includes a valve portion and a pressure-receiving portion. The valve portion is movable in an opening direction to open the nozzle hole in response to pressure of fuel being pressurized by the compression unit and applied to the pressure-receiving portion. A regulating unit is provided in the compression chamber for regulating movement of the valve element with respect to the opening direction.

Abstract: An injector, in particular an injector for a combustion engine, includes at least one nozzle module which has an injection nozzle and a supply line for a fluid under a supply pressure, and a valve-control module, which is in operative connection with the nozzle module, and at least one valve-closure member on which the supply pressure acts, and includes a piezoelectric actuator which is used to activate the valve-closure member and which is prestressed by a spring in the direction facing away from the valve-closure member, the piezoelectric actuator being activated by a valve-control unit which specifies a control gradient. The control gradient is a variable that is dependent upon the supply pressure.

Abstract: An actuator (4) is connected, on one side, to a valve needle (3), and on the opposite side, to a hydraulic piston (6) pertaining to a hydraulic length compensator. A working chamber (5) is divided by a tight separating membrane (9), into an actuator chamber (10) containing the actuator (4) and a fluid chamber (11) which can be filled with the fluid to be dosed in a pressurized manner while the actuator chamber (10) and the hydraulic chamber (7) are filled with a hydraulic fluid. A base pressure can be produced in the hydraulic fluid by means of the pressure of the fluid to be dosed, which is transmitted through the separating membrane (9).

Abstract: A fuel injector (1) for an internal-combustion engine has a shell (2) provided with two opposite terminal portions; the first terminal portion (4) has an inlet (7) for supply of the fuel and is generally designed to extend outside the engine, whilst the second terminal portion (5) has a nozzle (9) communicating with said inlet (7), is designed to be housed in the engine and has, in the radial direction, dimensions smaller than those of the first portion (4); the injector (1) further has an actuator (16) and a servo valve (15) housed in the first terminal portion (4); the servo valve (15) is provided with an open/close element (32), which can slide axially, under the action of the actuator (16) and substantially in a fluid-tight way, in a seat (27) and is subjected to an axial resultant of pressure of the fuel that is substantially zero; the fuel inlet (7) is made laterally in an intermediate axial position between the actuator (16) and the nozzle (9).

Abstract: A fuel injector in injection systems for internal combustion engines having a valve body containing a control chamber that can be pressure-relieved and can be acted on with fuel via an inlet throttle and can be pressure-relieved via an outlet throttle. A first actuator can actuate a closing element. The valve body is connected to a holding body that has a nozzle body connected to it, which encompasses an injection valve element. In order to relieve the pressure in the control chamber, an additional, second outlet throttle is provided, whose closing element can be actuated either by an additional actuator or as a function of the power supply to a double-switching actuator.

Abstract: A fuel injector includes an auxiliary valve member that can assist in raising a mean injection pressure, increase a nozzle valve opening pressure, and hasten the closure rate of a nozzle valve member over an equivalent fuel injector without the auxiliary valve. The auxiliary valve member is fluidly positioned between a needle control chamber and a high pressure space, which includes a fuel pressurization chamber within the fuel injector. The auxiliary valve member includes a closing hydraulic surface exposed to fluid pressure in the high pressure space. The plumbing and the auxiliary valve member allow high pressure fuel to act upon a closing hydraulic surface of the nozzle valve member to increase valve opening pressure and mean injection pressure. The needle control chamber may be vented or may be a closed volume when the auxiliary valve member is in its closed position.

Abstract: An injection nozzle is proposed in which the nozzle needle has an annular groove in the vicinity of the transition between the blind hole and the nozzle needle seat. In seat hole injection nozzles, the annular groove is disposed in the vicinity of the injection orifice(s). The annular groove reduces the tolerance of the flow resistance of the injection nozzle with a partial stroke of the nozzle needle and thus permits a more precise measurement of the fuel quantity injected.

Abstract: A fuel injector for an internal combustion engine having a crankshaft is disclosed. The fuel injector has plunger to displace fuel and an electronically controlled spill valve. The fuel injector also has a nozzle member having at least one orifice and a valve needle disposed within the nozzle member, and movable against a spring bias to selectively inject pressurized fuel through the at least one orifice. The fuel injector also has an electronically controlled check valve. The valve needle is automatically moved to inject pressurized fuel when the pressure of the fuel within the fuel injector reaches a predetermined valve opening pressure determined by a spring bias. Valve elements of the electronically controlled spill and check valves are both in a flow blocking position before the pressure of the fuel within the fuel injector reaches the predetermined valve opening pressure. Injection terminates when the valve element of the electronically controlled check valve is moved to a flow-passing position.

Abstract: A fuel injection arrangement, which comprises a fuel source and a fuel nozzle connected thereto, including a fuel chamber and a needle valve arrangement in connection with the fuel chamber for controlling the fuel injection and an arrangement for bringing about a force effect on the valve of the needle valve arrangement in the closing direction thereof; a fuel control arrangement by means of the different switching positions of which, the fuel flow connection is connectable between the fuel source and the fuel chamber of the fuel nozzle as well as between the fuel source and the arrangement for bringing about a force effect, in which the fuel control arrangement comprises a mechanical force unit for changing its switching positions.

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: A fuel injector, in particular a fuel injector for fuel-injection systems of internal combustion engines, including a piezoelectric or magnetostrictive actuator, which, via a valve needle, actuates a valve-closure member arranged on the valve needle, the valve-closure member cooperating with a valve-seat surface to form a sealing seat, the fuel injector having an hydraulic compensation chamber. A pressure piston cooperates with the compensation chamber, which is filled with hydraulic fluid via an hydraulic fluid inlet. The actuator is arranged between the pressure piston and the valve needle and displaceable in the axis of the valve needle and the pressure piston.

Abstract: An apparatus and method of compensating for thermal expansion and tolerance variations (wear, brinelling, mounting distortion) in a fuel injector is provided. The apparatus includes a magneto-hydraulic thermal expansion compensator containing magnetically-active fluid positioned in operative contact with the fuel injector actuation element. A electromagnetic coil is provided proximate the magneto-hydraulic compensator. Magnetic flux generated by the electromagnetic coil causes the viscosity of the magnetically-active fluid within the magneto-hydraulic compensator to increase, causing the magneto-hydraulic compensator to become substantially rigid during actuation of the fuel injector.

Abstract: A fuel injector for the direct injection of fuel into the combustion chamber of an internal combustion engine includes a piezoelectric or magnetostrictive actuator, a hydraulic coupler, the hydraulic coupler having a master piston and a slave piston that are connected to a pressure chamber, and the pressure chamber being filled with an hydraulic fluid. The pressure chamber is sealed from an actuator chamber by a first seal and from a valve interior chamber by a second seal.

Abstract: Common rail fuel injectors typically have difficulty in changing an injection rate during an injection event. Fuel injectors for this common rail fuel injection system include a multi-position admission valve. The admission valve is stoppable at a middle position to inject fuel at a low rate. The lower rate is accomplished by leaking some fuel to drain to reduce injection pressure. The admission valve is also stoppable at a fully open position to inject fuel at a high rate. Fuel injection events are ended, and the fuel injectors maintained between injection events, with the admission valve member in contact with a supply seat to close the high pressure supply passage. This strategy can be used in conjunction with a spring-biased needle valve member to expand fuel injector capabilities.

Abstract: An injection device for injecting fuel comprises a nozzle needle (2), which is arranged in a nozzle body (1), and a micro-bore (10) formed in the nozzle body (1), in which at least one injection hole (8) is configured. Here one tip (3) of the nozzle needle (2) projects into the micro-bore (10) in such a way that the tip (3) is arranged at the level of the injection holes (8) in the axial direction (X—X) of the nozzle needle, with recesses being formed in the tip at the tip (3) of the nozzle needle (2) level with the injection holes (8), in order to ensure a minimum distance between the tip (3) and the injection holes (8).

Abstract: A controller for controlling a needle valve of a spring closing type fuel injector includes a fluid assist selectively exerting a force on the needle valve, the force acting in cooperation with a bias exerted by a return spring on the needle valve to effect a relatively low valve opening pressure of the needle valve and relatively very high valve closing pressure. A spring closing type fuel injector and a method for controlling a needle valve of a spring closing type fuel injector are further included.

Abstract: A temperature compensated actuator device comprises a piezoelectric stack having first and second ends along a central axis and having a first thermal expansion coefficient; and a compensator arranged on one end of the piezoelectric stack. The compensator comprises a first member in form of a cylinder; a second member in form of a piston plate wherein the first member and the second member are arranged movably along the axis with respect to each other and define a hollow space between them; and a compensation member having a thermal expansion coefficient higher than the first thermal expansion coefficient for filling the hollow space.

Abstract: Engineers have determined that the performance of fuel injectors, including those used in common rail fuel injection systems, can be increased, and undesirable emissions reduced, by controlling the mass flow rate of fuel injected into a combustion chamber during an injection event. While a number of fuel injectors have been developed that have limited rate shaping capabilities, the ability to produce some front end rate shapes has not been possible. In an effort to increase rate shaping capabilities, the present invention includes a valve assembly having at least one valve member that is movable between a plurality of positions to control fluid communication between a number of fluid inlets and outlets.

Abstract: The injector has a cylindrical body, which houses an injection nozzle regulated by an injection valve provided with a moveable pin, a fuel supply channel, an injection chamber communicating with the fuel supply channel housing a lower portion of the pin and delimited at the bottom by a valve seat for the injection valve, a control chamber communicating with the fuel supply channel and housing an upper portion of the pin, and a control valve, which is of the poppet type and is actuated by an electromagnetic actuator in order to move between a closed position and an open position, in which it puts the control chamber in communication with a low-pressure fuel exhaust passage.

Abstract: An annular notch is provided in the body seat associated with the nozzle valve of an ALCO-type diesel injector. The notch extends from (i) an upper edge that is on the seat and is above the imaginary edge that would have been the sac inlet edge had the notch not been provided to (ii) a lower edge below such imaginary edge. The notch has a lowest wall that, at least at the portion of its length where such lowest wall approaches such lower edge, has a given angle-to-vertical of less than 60°.

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.