Abstract: A fuel injector with a magnetic coil, which cooperates with an armature acted upon by a restoring spring, the armature forming an axially movable valve part together with a valve needle. A valve-closure member, which forms a sealing seat with a valve-seat member, is provided at the valve needle. An inner pole and an outer pole form a magnetic circuit with the magnetic coil. A membrane is positioned at an inflow-side end face of the inner pole, which includes at least one orifice, which is covered by the inner pole in the dosed state of the fuel injector.

Abstract: A fuel injector, in particular an injector for direct injection of fuel into a combustion chamber of a mixture-compressing, spark-ignition internal combustion engine has a solenoid, which cooperates with an armature, and a magnetic internal pole and a magnetic external pole, the armature being connected in a force-locking manner to a valve needle for actuating of the fuel injector, the valve needle having on its injection end a valve-closure member, which cooperates with a valve seat. At least one permanent magnet is arranged in a connecting area between the internal pole and the external pole.

Abstract: A fuel injector for direct injection of fuel into a combustion chamber of a mixture-compressing, spark-ignited internal combustion engine, has a nozzle body that forms a housing body with an external pole and a coil housing, a magnet coil that is electrically energizable by way of a lead and a plug contact, and a central fuel supply. The lead and the fuel supply are positioned together in an adapter that can be placed onto an inflow end of the housing body and is joinable thereto.

Abstract: An injector, especially for common rail injection systems of Diesel engines, has a nozzle needle, a control piston for actuating the nozzle needle, a valve that actuates the control piston and that is triggered by via an outlet throttle and an inlet throttle, and a hydraulic stop for the control piston, such that the flow from the inlet throttle to the outlet throttle at the narrowest cross section can additionally be throttled. The control piston is embodied conically on its offset top side oriented toward the outlet throttle or the inlet throttle.

Abstract: A fuel injector, e.g., for fuel injection systems of internal combustion engines, for direct injection of fuel into the combustion chamber of an internal combustion engine. The fuel injector includes a solenoid, an armature, which is acted upon in a closing direction by a restoring spring, and a valve needle, which is linked in a force-locking manner to the armature, for actuating of a valve-closure member, which together with a valve-seat surface forms a sealing seat. The armature includes a first armature part and a second armature part, the restoring spring is supported on the first armature part and the second armature part is linked in a force-locked manner to the valve needle. The valve needle is acted upon in the closing direction by the restoring spring via the first armature part and the second armature part so that the valve-closure member is held in a sealing position on the valve-seat surface.

Abstract: A fuel injector, in particular a fuel injector for fuel-injection systems of internal combustion engines, includes a first magnetic coil cooperating with a first armature, a second magnetic coil cooperating with a second armature, and a valve needle which is in force-locking connection with the first armature via a first flange and to the second armature via a second flange, to actuate a valve-closure member. A restoring spring acts upon the valve needle in a closing direction of the fuel injector. A first positioning spring, situated between the first flange and the first armature, acts upon the first armature in the closing direction of the fuel injector, while a second positioning spring, situated between the second flange and the second armature, acts upon the second armature in an opening direction of the fuel injector.

Abstract: An electromagnetic actuator for a fluid pressure control valve in a fuel injector for an internal combustion engine is disclosed. The fuel injector comprises a control module including a fuel pressure control valve; an armature connected to the fuel pressure control valve; and a stator assembly including a magnetic core comprising of at least two segments and a bobbin. The stator assembly, when it is energized by a power source, produces a magnetic field to draw the armature towards the stator assembly.

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: A fuel injector including a control valve arrangement for controlling fuel pressure within a control chamber comprises a control valve member which is movable between a first position in which the control chamber communicates with a source of high pressure fuel and a second position in which the control chamber communicates with a low pressure fuel drain and communication between the control chamber and the source of high pressure fuel is broken. The control valve arrangement includes a restricted flow path for restricting the rate of flow of fuel from the source of high pressure fuel to the control chamber when the control valve member is moved towards its first position. The provision of the restricted flow path prevents unbalanced hydraulic forces acting on the control valve member when it moves towards its first position, which can otherwise lead to valve needle dither between injecting and non-injecting states.

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 injector having an arrangement to stabilize the temperature of its components within an engine cylinder in a direct injection application. The fuel injector includes a body, an armature, a needle, a swirl generator, and a seat. The body has an inlet portion, an outlet portion, a body passage, extending from the inlet portion to the outlet portion along a longitudinal axis of the fuel injector. The armature is located proximate the inlet portion of the body, and is operatively connected to the needle. The needle is provided with a substantially uniform cross-sectional area, and the body is selected to surround the needle and form a body passage that has an average cross-sectional area less than two times the substantially uniform cross-sectional area of the needle.

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: A method involves retrofitting conventional injectors with needles having magnetostrictive portions and wound coils configured and disposed so as to subject the magnetostrictive portions of the needles to ultrasonically oscillating magnetic fields.

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: The injector has a hollow body housing the body of the metering valve, which has a discharge hole for discharging the usual control chamber. The hole comes out at a flat surface of the valve body, and is engaged by a flat surface of a plate, under the control of an armature of an electromagnet. The armature is in the form of a disk, has substantially no stem, is connected to the hollow body by a leaf spring hinge, and has a surface having a spherical-bowl-shaped recess. A ball is located between the recess and another recess carried by a second surface of the plate. The valve body is fixed to the hollow body by a ring nut of a given height. And, to cover the distance between the valve body and the armature, a spacer member is preferably formed in one piece with the valve body.

Abstract: A fuel injection valve includes: a magnetic barrel body made of a magnetic material and shaped substantially into a barrel, a core barrel made of a magnetic material and shaped substantially into a barrel, a valve seat member positioned on a downstream side of the core barrel and disposed in the magnetic barrel body, a valve body positioned between the core barrel and the valve seat member, an O-ring positioned in a vicinity of a flange portion of the magnetic barrel body, a fuel filter assembly disposed at the first end on the fuel's influx side of the magnetic barrel body. A flange of the fuel filter assembly is made of a material lower in hardness than the magnetic material of the magnetic barrel body. The flange of the fuel filter assembly has a diameter larger than the diameter of the flange portion of the magnetic barrel body.

Abstract: A fuel injection system for internal combustion engines includes a plurality of injection valves, each connected to an injection line and each having a nozzle chamber and a control chamber, which both communicate with the injection line; a valve member, which controls the injection openings and is actuatable via a first control face, located in the nozzle chamber and acting in the valve opening direction, and via a second control face located in the control chamber and acting in the valve closing direction; a first valve for controlling the pressure prevailing in the control chamber; and a second valve for switching the injection pressure. Both valves, have a common valve body with the valve body stroke H2 required to close the first valve being greater than the stroke H1 required to open the second valve.

Abstract: A fuel injector (10; 100) comprises an inlet (60) from which fuel can be transferred into a cavity (61) of the injector, at least one outlet orifice (86) communicating with said cavity (61), and ejecting means (44, 88) operable to apply force to fuel in said cavity to cause said fuel to be ejected through said orifice as discreet charges at pre-determined intervals. The operation of said ejecting means (44, 88) is also operable to transfer further fuel into said cavity (61).

Abstract: A valve with an integral orifice for use in gas feeding equipment provided with a pressure-type flow volume control device to be employed for manufacturing of semi-conductors and chemical goods. The valve with an integral orifice has the excellent flow rate control characteristics by improving the processing accuracy of the orifice and preventing the distortion of the orifice at the time of assembling. The orifice is formed in a stainless steel made orifice disc. The metal-made orifice disc with the orifice formed by separate processing and the synthetic-resin-made valve seat body are removably assembled, wherein the orifice disc and the synthetic resin made valve seat body are fixed airtight to the valve main body by pressing the valve seat body via a metal inner disc.

Abstract: A fuel injector, in particular a fuel injector for fuel-injection systems of internal combustion engines, includes a valve needle cooperating with a valve-seat surface to form a sealing seat, and has an armature engaging with the valve needle, the armature being axially moveable on the valve needle and damped by a damping element made of an elastomer. The damping element is positioned in a recess of the armature at the valve needle in such a way that the valve needle is connected to the armature in the radial direction via the damping element.

Abstract: The injector has a hollow body supporting an ordinary injection nozzle and a metering valve for metering the fuel to be injected; and a support defined by a sleeve and by an end wall. The sleeve houses an electromagnet controlling the metering valve, and is fitted to the hollow body. For which purpose, there is provided a leaf spring having a ring-shaped portion engaging the end wall of the support; and a number of elastic blades, each terminating with a hook-shaped appendix which engages a corresponding retaining element on the hollow body.

Abstract: A fuel injector, in particular for a high-pressure injector for direct injection of fuel into a combustion chamber of an internal combustion engine, has compression of a fuel/air mixture with spark ignition. On the downstream end of the valve a valve seat element is provided, to which a perforated disk acting as a flow restrictor is connected downstream. A swirl element is situated upstream from the valve seat which imparts an atomization-promoting rotational motion to the fuel to be injected. In the valve seat element downstream from the valve seat, an elongated outlet orifice is provided which opens directly into an orifice in the perforated disk attached to the valve seat element. The width of the outlet orifice is greater than the width of the orifice in the perforated disk, at least at its narrowest location, so that it is possible to adjust the steady-state flow rate of the valve at the orifice.

Abstract: A fuel injector for fuel injection systems of internal combustion engines has a valve-closure member that is in working engagement with a valve needle and that coacts with a valve-seat surface positioned in an orifice of a valve-seat member to form a sealing seat. The fuel injector has at least one spray discharge opening positioned in the valve-seat member. Between the valve-seat surface and the spray discharge opening, a second surface that make a more acute angle with the center axis of the fuel injector than the valve-seat surface, is formed by the orifice of the valve-seat member. A closure element extension whose enveloping surface forms an obtuse angle with the contiguous contour of the valve-closure member is positioned at the downstream end of the valve-closure member.

Abstract: A fuel injector, particularly a fuel injector for fuel injection systems of internal combustion engines, has a magnetic coil, an armature acted upon in a closing direction by a resetting spring and a valve needle connected to the armature by force-locking for operating a valve-closure member, which forms a sealing seat together with a valve-seat surface. The armature has a pot-shaped axial extension, in which at least one cutout is formed.

Abstract: A fuel injector is described, particularly for fuel injector systems of internal combustion engines, including an actuator, a valve needle actuatable by the actuator for actuation of a valve-closure member, which together with a valve-seat surface forms a sealing seat, and a swirl device, having at least one swirl channel through which fuel flows having a tangential component regarding a longitudinal axis of the fuel injector. The axial position of a bypass disk, which is mechanically linked to a valve needle, determines a cross section of at least one bypass channel, which bypasses the at least one swirl channel without a tangential component.

Abstract: An electromagnetic fuel injection valve includes a valve housing coupled to at one end thereof to a valve seat member; a stationary core coupled to the other end of the valve housing; and a valve assembly comprised of a movable core slidably accommodated in the valve housing, and a valve member connected to the movable core through a rod portion and adapted to cooperate with the valve seat. In the electromagnetic fuel injection valve, the valve housing is provided with a guide portion on which the valve assembly is axially slidably carried, and a high-hardness coating of diamond-like carbon including silicon is formed on an outer peripheral surface of the valve assembly contacting with the guide portion. The surface roughness Rmax of the high-hardness coating is set in a range of 0.05 to 0.2 ?m.

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 located at the first end of the tube assembly and that has an integral retaining portion; 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 (1) for fuel injector systems of internal combustion engines has a valve-closure member (4) which is mechanically linked to a valve needle (3) and cooperates with a valve-seat surface (6) of a valve-seat member (5) to form a sealing seat. A turbulence-producing element is provided in the valve-seat member (5), situated downstream from the sealing seat, and its center line (38) preferably forms an angle different from zero with the center line (39) of the fuel injector (1), a threaded rod (36) being pressed into the valve-seat member (5) as the turbulence-producing element.

Abstract: A hydraulically actuated, intensified fuel injector includes a controller achieving a desired injection control strategy by selectively independently porting actuating fluid to and venting actuating fluid from an intensifier piston to control the compressive stroke of the intensifier piston and selectively independently porting actuating fluid to and venting actuating fluid from a needle valve to control the opening and closing of the needle valve during the injection event. A method of control is further included.

Abstract: 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 a valve 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 injector includes a homogenous charge nozzle outlet set and a conventional nozzle outlet set controlled respectively by inner and outer needle value members. The homogenous charged nozzle outlet set is defined by an outer needle value member that is moveably positioned in an injector body, which defines the conventional nozzle outlet set. The inner needle valve member is positioned in the outer needle valve member. The outer needle valve member is a piece component that includes at least one external guide surface, an external value surface and an internal valve seat.

Abstract: A hydraulic control valve for a fuel injector for an automotive engine, which includes a piezoelectric actuator and a hydraulic valve mechanism. The hydraulic valve mechanism converts a mechanical deformation of the piezoelectric actuator produced as a result of application of a voltage into a hydraulic pressure to move a valve member for opening and closing a fluid port. The hydraulic valve mechanism is so designed that the piezoelectric actuator produces a maximum output force which works to develop the hydraulic pressure when opening the fluid port through the valve member and decreases after the fluid port is opened and which is set smaller than one-half of a maximum possible output force of the piezoelectric actuator under application of a maximum working voltage to said piezoelectric actuator, thereby ensuring a maximum movement of the valve member at high energy efficiency under application of the voltage within a working voltage range.

Abstract: Fuel injector, in particular, a fuel injector for the direct injection of fuel into a combustion chamber of an internal combustion engine is described having an actuator for actuating a valve needle, the valve needle having on an injection-side end a valve-closure member which forms a sealing seat together with a valve-seat surface, which is formed on a valve-seat member. Fuel channels are arranged in a valve needle guide, connected to the valve-seat member or designed as a single piece with it, in several rows circumferentially in the valve needle guide, at least one row of fuel channels being arranged, in the resting state of the fuel injector, above a guide line of the valve-closure member.

Abstract: A fuel injector, in particular a fuel injector for fuel injection systems of internal combustion engines, has a piezoelectric or magnetostrictive actuator, a valve closing element that can be actuated by the actuator and that works together with a valve seat face to form a seal seat, and a temperature compensation device. The temperature compensation device has a housing that is elastically deformable along a direction of actuation of the actuator, and has at least one throttle that connects an interior space of the housing with a fuel inlet of the fuel injector. The cross-section of this throttle is dimensioned such that an entry and exit of fuel into the housing of the temperature compensation device is enabled when there is a temperature-caused change in length of components of the fuel injector.

Abstract: A fuel injector for fuel-injection systems of internal combustion engines includes an actuator, a valve needle, which is able to be activated by the actuator to actuate a valve-closure member, which, together with a valve-seat surface formed at a valve-seat member, forms a sealing seat; and a plurality of spray-discharge orifices which is formed in the valve-seat member. At a discharge-side end of the fuel injector, a nozzle-orifice cover is positioned, which shields the spray-discharge orifices from the combustion chamber of the internal combustion engine.

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: 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 assembly comprising an engine camshaft driven piston plunger in a plunger body, a control valve, an electromagnetic actuator for stroking the control valve between limiting positions and a valve stop assembly establishing a first limiting valve stroke position when the control valve is fully open and a second valve stroke position corresponding to a reduced fuel delivery pressure prior to a main fuel pressure pulse in a fuel injection event.

Abstract: A two stage intensifier capable of multiple intensification rates comprises a stepped top portion and a shoulder portion, each being actuated by separate fluid passages. A stepped top portion is received into an upper bore of a piston bore and a shoulder is received into a lower bore. The stepped top forms a seal with the upper bore to prevent direct fluid communication between a first actuation cavity above the stepped top and a second actuation cavity above the shoulder.

Abstract: A fuel injection valve having a valve body (5), in which a pistonlike valve member (7) is guided longitudinally displaceably in a bore (15) embodied as a blind bore. A conical valve seat (23) and at least one injection port (25) are embodied on the bottom face of the bore (15), and the injection port connects a pressure chamber (11), formed between the portion (107) of the valve member (7) toward the combustion chamber and the bore (15), with the combustion chamber. On the end toward the combustion chamber of the valve member (7), there is a valve member tip (13), on which a first conical face (30), adjacent to the valve member (7), and a second conical face (32), disposed on the combustion chamber side of the first conical face, are embodied.

Abstract: The invention relates among others to a method for producing outlet openings (32) in a valve, in particular a fuel injection valve. The injection valve has a fuel inlet (2), an excitable actuating device (1, 2, 19) by which a valve closing member (28) is movable, a fixed valve seat (27) embodied on a valve seat element (26), with which seat the valve closing member (28) cooperates to open and close the valve, and at least one outlet opening (32), as a fuel outlet, provided downstream of the valve seat (27). The at least one outlet opening 32 is produced in such a way that in a first method step, a through hole is created in the valve seat element (26), and in a second method step, from the ejection end of the through hole, an outlet region is created that is altered in shape and/or size and/or contour compared to the through hole.

Abstract: A fuel injector (1) for fuel injection systems of internal combustion engines has a solenoid (10), a valve needle (3) pressed in the closing direction by a return spring (23) to activate a valve closing member (4), which together with a valve seat surface (5) forms a sealing seat, and an armature (20) in friction-locking connection with a valve needle (3). A first guide sleeve (35) and a second guide sleeve (36) are connected to the valve needle (3). The armature (20) has radial play with respect to the valve needle (3) as a result of the central opening (34), the diameter of which is greater than the diameter of the valve needle (3).

Abstract: A fuel injector, in particular for direct injection of fuel into the combustion chamber of an internal combustion engine, includes a valve-closure member which forms a sealing seat together with a valve-seat surface which is formed on a valve-seat member, and several injection orifices, each of which is connected with at least one spiral groove so that an outer edge of the swirl grooves coincides in part with a circumferential edge of the injection orifices. The swirl grooves extend generally perpendicular to a center line of the injection orifice associated with them.

Abstract: An improved fuel injector is provided which effectively controls fuel injection events using two injection control valves which operate in series to control the movement of a nozzle valve element. An outer injection control valve and actuator assembly operates to control fluid pressure in a control volume adjacent an inner injection control valve thereby controlling the movement of the inner control valve which, in turn, controls fuel pressure in an inner control volume adjacent one end of the nozzle valve element. A particular design of the inner injection control valve prevents control valve oscillations thereby minimizing unwanted fuel injection variations.

Abstract: A 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 within one quadrant of the circle. A channel is formed between the seat orifice and the metering disc that allows the fuel injector to target fuel spray generally within an arcuate sector of at least 90 degrees about the longitudinal axis of the metering disc. A method of targeting is also provided.

Abstract: The invention is based on a hydraulic control device (60), in particular for an injector (16) of a fuel injection system (10) in motor vehicles. Known control devices have a piezoelectric actuator, which controls a multi-position valve (75), embodied as an outward-opening valve with a valve member (74) guided in a valve bore (76). According to the invention, it is proposed that a booster (62) that reverses the deflection motion of the actuator (52) be disposed between the actuator (52) and the valve member (74), and that the multi-position valve (75) be embodied as an inward-opening 3/2-way valve. The valve member (74) of this valve, in operative connection with a valve seat (98) and a control edge (96), alternatingly opens or closes pressure fluid connections between pressure fluid conduits (86, 88, 92).

Abstract: A valve needle (2), in particular for spraycoating apparatus and their spraycoating devices. The valve needle (2) has a shank (4) and a plunger (8) affixed thereon. The shank (4) is made of another material than is the plunger (8). A preferred material for the shank (4) is an industrial ceramic.

Abstract: A fuel injector for fuel injection systems of internal combustion engines and a method of manufacturing same are described. The fuel injector includes a valve seat body into which a valve seat face is introduced, which cooperates with a valve closing body to form a sealing seat, and a nozzle body to which the valve seat body is fixedly connected. The valve seat body is insertable into the interior of the nozzle body and on its downstream side it has a partially spherical outside geometry, which rests on a bearing surface of a seat body recess in the nozzle body. Valve seat body is mounted so it can rotate relative to the nozzle body on the bearing surface until its position is finally secured, and it may be aligned by a centering mandrel.

Abstract: The fuel injection device has a fuel injection valve that has an injection valve member, which is guided so that it can slide in a valve body and controls at least one injection opening and which can be moved in the opening direction, counter to the force of a closing spring contained in a spring chamber by means of the pressure prevailing in a pressure chamber of the fuel injection valve. Highly pressurized fuel is supplied from a high pressure source to the pressure chamber of the fuel injection valve. An electrically controlled valve at least indirectly controls a connection of the pressure chamber to a relief chamber and connects the pressure chamber to the relief chamber in order to terminate the fuel injection. The pressure chamber of the fuel injection valve has a connection to the spring chamber, which connection contains a check valve that opens toward the pressure chamber.

Abstract: Valve body for a fuel injector; the valve body is provided with a cylindrical tubular container which has a central cylindrical cavity, a valve seat which is disposed at a lower end of the tubular container, a pin which can engage the valve seat and is accommodated in a sliding manner inside the tubular container, a lower guide for the pin, which guide is accommodated in the valve seat, and an upper guide for the pin which is contained in a support element, which is disposed at an upper end of the tubular container and defines a pair of supply apertures which open into the cavity for supply of fuel to the cavity itself.