Abstract: A fuel injector and servovalve for an internal combustion engine.

Abstract: A fuel injection valve includes a housing having a wall surface on an opposite side of the nozzle hole. A fuel passage opens in the wall surface, and communicates with a nozzle hole through a nozzle cavity. The nozzle cavity accommodates a valve element. A cylinder is substantially in contact with the wall surface at one end, and slidably accommodating one end of the valve element. The cylinder partitions the nozzle cavity substantially into a fuel accumulator chamber and a pressure control chamber. The fuel accumulator chamber accumulates fuel supplied from the fuel passage. The pressure control chamber accumulates fuel for manipulating the valve element. The cylinder has an outer wall defining a deflecting surface for radially outwardly deflecting fuel flowing from the fuel passage.

Abstract: Provided is a highly durable laminated piezoelectric element wherein a stress generated at a portion, i.e., the boundary between an active region and inactive region, is reduced. A method for manufacturing such laminated piezoelectric element is also provided. The laminated piezoelectric element has a laminated structure (15) wherein a plurality of piezoelectric layers (11) and internal electrode layers (13) are alternately laminated. The piezoelectric layer (11) contains a metal element other than those elements constituting piezoelectric ceramic, i.e., the main component of the piezoelectric layer (11), and at a portion (11a) of the piezoelectric layer (11) at the vicinity of an end of the internal electrode layer (13), metal particles having a metal element as a main component exist. The content of the metal at the portion (11a) at the vicinity of the end is higher than the content of a compound of the metal element and a nonmetal element.

Abstract: An internal combustion engine fuel injector (1) has a rod (10) movable along an axis (3) to open/close a nozzle, and a servovalve (7) having a control chamber (23) with a discharge passage (26, 48) which is opened/closed by a shutter (17) movable axially under the control of an electro-actuator; the servovalve also has a fixed axial rod (33) having an outer lateral surface (34) through which the discharge passage (26, 48) comes out; the shutter (17) is fitted to the axial rod (33) to slide axially in substantially fluidtight manner, and, when closing the discharge passage (26, 48), is subjected to substantially zero resultant axial pressure by the fuel; and a calibrated portion (42, 52) of the discharge passage (26, 48) is formed close to the outlet of the discharge passage to produce swirl and/or cavitation in the fuel outflow near to the closing area between the shutter (17) and the axial rod (33).

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

Abstract: A fuel injection valve includes a nozzle body and a plate. The nozzle body includes an injection orifice, through which fuel is injected, a needle that controls the injection through the injection orifice, and a needle-receiving bore that receives the needle. The plate is adjacently provided to the nozzle body for defining a fuel passage therein, through which fuel is supplied to the needle-receiving bore. The plate has an annular groove, which connects the fuel passage with the needle-receiving bore, at an end surface of the plate toward the nozzle body.

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 system having one high-pressure fuel pump and one fuel injection valve, communicating with the high-pressure fuel pump, for each cylinder of an internal combustion engine. A pump work chamber is defined by a pump piston, and the fuel injection valve has an injection valve member by which at least one injection opening is controlled. An electrically actuated control valve controls a communication of the pump work chamber with a relief region and a movable control piston acts at least indirectly in the closing direction on the injection valve member, and the control piston, on its side remote from the at least one injection valve member, is acted upon at least indirectly by the pressure prevailing in the pump work chamber. The control piston, with its side toward the injection valve member, defines a control chamber.

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

Abstract: In an injector, a first shaft portion of a needle is slidably supported by a first sleeves which is loosely received in a first internal chamber, and a second shaft portion of the needle is slidably supported in a body. Thereby, the first and second shaft portions are supported by the different members, and a relatively large clearance is formed on a radially outer side of the first sleeve.

Abstract: Provided is a nozzle unit for use in a bonding device in which bonding between a first member and a second member is effected by providing a bonding member that has been melted by heating at a bonding position where the first member and the second member are to be bonded to each other. The nozzle unit includes: a cylindrical nozzle assembly having an accommodating space accommodating the bonding member, and an opening which allows ejection of the bonding member accommodated in the accommodating space onto the bonding position, which has a diameter larger than the diameter of the bonding member, and which communicates with the accommodating space; and a holding/releasing member for releasably holding the bonding member within the accommodating space.

Abstract: The movement of an injection valve member, which can be longitudinally displaced and guided in a housing and which is used to close and release injection openings, is controlled of a hydraulic control device which comprises a control body which is maintained in a central bore on the periphery thereof and which is provided with a control duct which is connected to a control area on a lower front-surface side of the control body and which is sealed on another upper front-surface side of the control body and which can be connected to a low pressure area by a pilot 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: 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 injector having an injection nozzle comprising a nozzle body being provided with a nozzle bore, an outer valve received within the nozzle bore and being engageable with a first seating to control fuel delivery through a first set of one or more nozzle outlets. The outer valve is provided with an outer valve bore within which an inner valve is received the inner valve being engageable with a second seating to control fuel delivery through a second set of one or more nozzle outlets. The fuel injector further includes an injection control chamber for fuel and pressure control means for controlling the pressure of fuel within the injection control chamber.

Abstract: The fuel injector comprises a hollow casing, fixed on which is a nozzle having a nebulizer for the fuel under pressure, a needle axially mobile for opening and closing the nebulizer by means of a first end thereof, and a control rod, substantially coaxial with the needle and in direct engagement therewith. The needle is normally pushed into a closing position of the nozzle by the fuel under pressure acting on the rod, aided by a compression spring, which acts on the needle through a sleeve that is in axial engagement with a portion of the rod. The sleeve further comprises a surface designed to engage at the front and directly one end of the needle. The spring engages another surface of the sleeve so as to transmit its action directly onto the needle.

Abstract: The invention relates to a fuel injector having an injector housing which has a high-pressure fuel connection which is connected outside the injector housing to a central high-pressure fuel source and inside the injector housing to a pressure space. From the fuel injector highly pressurized fuel is injected into a combustion chamber of an internal combustion engine as a function of the pressure in a control space when a nozzle needle opens In order to provide a fuel injector which can be manufactured inexpensively, the pressure in the control space is controlled directly by a magnetic actuator.

Abstract: The invention relates to a fuel injection valve for intermittent fuel injection into the combustion chamber of internal combustion engines. A needle-shaped injection valve member (34) is arranged in the high-pressure fuel chamber (30) adjacent to the injection valve seat (32), said injection valve member co-operating with the injection valve seat (32) and defining, in a piston-type manner, the cylinder chamber (36) which is connected to the high-pressure inlet (26). The booster piston (28) is controlled by means of the control valve (34) embodied as a flat seat valve, increasing the pressure of the fuel in the high-pressure fuel chamber (30) for an injection, and thus lifting the injection valve member from the injection valve seat. In this way, the injection is carried out with increased pressure.

Abstract: The invention relates to a fuel injection device with a multi-part injector body containing a pressure booster that can be actuated by means of a differential pressure chamber, and includes a pressure booster piston that seals a working chamber off from the differential pressure chamber. An on-off valve disposed above the injector body can actuate the fuel injection device. A pressure change in the differential pressure chamber occurs via a central control line that extends through the pressure booster piston of the pressure booster.

Abstract: Disclosed is a valve comprising a valve member (72) that is guided so as to be movable in the direction of the longitudinal axis (73) thereof, extends into a valve pressure chamber (77), and is provided with a sealing surface (81) on a face which runs perpendicular to the longitudinal axis (73) thereof inside the valve pressure chamber (77). Said sealing surface (81) of the valve member (72) cooperates with a valve seat (79) that runs perpendicular to the longitudinal axis (73) thereof so as to at least largely close an opening (78) which is surrounded by the valve seat (79) relative to the valve pressure chamber (77). A connection (64) to a low-pressure area lies immediately next to said opening (78).

Abstract: In some fuel injectors, a variable flow rate valve is used to control actuation fluid flow rates to and from an intensifier piston. Over time, the variable flow rate valve is subjected to wear that can affect the predictability of the injection rate shape. The present invention reduces variable flow rate valve wear within a fuel injector, at least in part, by guiding a variable flow rate valve member along guide bore walls within a rate shaping path. The rate shaping path and an unrestricted path are defined by an injector body. When in a retracted position, a moveable intensifier piston includes a first hydraulic surface that is exposed to hydraulic pressure in the unrestricted path and a second hydraulic surface that is exposed to hydraulic pressure in the rate shaping path. The variable flow rate valve member defines a central passage with a predetermined flow area and includes a side surface that separates a closing hydraulic surface from an opening hydraulic surface.

Abstract: A first valve element (32) and second valve element (34) are arranged in a pressure switching chamber (30) of a three-way valve (8). When switching a destination of a fuel flow passage (15) from a high pressure fuel feed passage (5a) to a low pressure fuel return passage (26a), the state where the first valve element (32) is open and the second valve element (34) is closed is switched through a state where the first valve element (32) and second valve element (34) are both closed to a state where the first valve element (32) is closed and the second valve element (34) is open. Fuel pressure of a pressure control port (55) sealed by a sliding seal face (53) formed at an outer circumference of the second valve element (34) is used to control an opening timing of a needle valve (9).

Abstract: A control servo valve (8) is housed inside the casing (2) of an internal combustion engine fuel injector (1), and has a piezoelectric actuator (40), and a control chamber (13) having a fuel outlet passage (21); the outlet passage (21) comes out inside an annular chamber (34) defined by a fixed tubular portion (25) and by a shutter (32), which engages the tubular portion (25) in substantially fluidtight manner and is slid axially by the piezoelectric actuator (40) from a closed position, in which it closes the annular chamber (34) and is subjected to a zero axial resultant force by the fuel pressure, to an open position, in which the outlet passage (21) communicates with a discharge conduit.

Abstract: The fluid injection valve has a first and second valve bodies fastened to each other, to bring a first end face of the first valve body into an intimate contact with a second end face of the second valve body. A first fluid passage in the first valve body is communicated with a second fluid passage in the second valve body. The first end face has a first depressed portion thereon, and the second end face has a second depressed portion thereon to be communicated with the first depressed portion to form a cavity to surround the first and second fluid passages.

Abstract: A common rail injector for injecting fuel through a high-pressure channel includes a control chamber, a control valve, and a drive unit. The control chamber applies pressure to a nozzle needle. The control valve switches communication of the control chamber between the high-pressure channel and a low-pressure channel. The drive unit selectively sets a valve element of the control valve on a low-pressure side seat or a high-pressure side seat. The drive unit has an actuator and a slide pin member. The slide pin member slides inside a slide hole to transmit a force to the valve element. A diameter of the low-pressure side seat is less than or equal to a diameter of the high-pressure side seat. The pressure in the control chamber is exerted as an assistance force, so that a high-pressure side seat closing load becomes less than or equal to a low-pressure side seat opening load.

Abstract: An electronically controlled fuel injector includes a reduced part count and complexity over similar fuel injectors without a substantial reduction in performance capabilities. This is accomplished by using a one-piece needle that is hydraulically balanced and biased toward a closed position with a spring positioned in the needle control chamber. Although subtle, this injector has some ability to control the fuel pressure when the needle valve is opening and closing by adjusting a relative timing of a pressure control valve opening relative to a needle control chamber, using separate electrical actuators. The invention is particularly applicable to fuel injectors that cycle through high and low pressure states during and between injection events, respectively. Cam actuated fuel injectors being particularly well suited.

Abstract: The injector includes a nozzle, a needle, a control chamber, a working fluid supply passage, an electric switching valve, a high-pressure gaseous fuel supply passage and a lubrication liquid fuel supply passage. The nozzle has an injection hole, through which high-pressure gaseous fuel is injected. The needle is axially reciprocably received in the nozzle to open and close the injection hole. The needle includes a sliding portion and a valve portion. The control chamber applies a pressure to the needle. The working fluid supply passage supplies liquid fuel to the control chamber. The electric switching valve controls an inflow/outflow of the liquid fuel to/from the control chamber. The high-pressure gaseous fuel supply passage supplies the high-pressure gaseous fuel to the injection hole. The lubrication liquid fuel supply passage supplies the liquid fuel from the working fluid supply passage to the sliding portion and the valve portion.

Abstract: A fuel injector with direct needle control has a nozzle needle guided in a nozzle body, and an actuator and a hydraulic pressure boosting unit that has an actuator pressure boosting piston connected to the actuator and a nozzle needle pressure boosting piston connected to the nozzle needle. The actuator pressure boosting piston and the nozzle needle pressure boosting piston both act on a coupler chamber. The nozzle needle pressure boosting piston contains a cylindrical chamber in which a control piston is axially guided, whose coupler chamber pressure surface is exposed to the coupler chamber and whose differential pressure chamber pressure surface is exposed to an inner differential pressure chamber contained in the cylindrical chamber. At its end oriented away from the coupler chamber, the nozzle needle pressure boosting piston is associated with an outer differential pressure chamber that communicates with the inner differential pressure chamber via a hydraulic connection.

Abstract: A fuel injector for a machine is disclosed. The fuel injector has a nozzle member with a first end and a second end. The first end of the fuel injector has at least one orifice. The fuel injector also has a control chamber located at the second end of the nozzle member with an end wall portion approximately orthogonal to an axial direction of the nozzle member. The fuel injector further has a port disposed in the end wall portion of the control chamber and at least one passageway in fluid communication with the control chamber via the port. The fuel injector additionally has a needle valve element with a tip end and a base end. The tip end is configured to selectively block fuel flow through the at least one orifice. The base end has a recess configured to cap off the port.

Abstract: A fuel system includes a fuel rail that communicates fuel at a first pressure through a fuel amplifier to a fuel injector. The fuel pressure amplifier increases the pressure from the first pressure to a second pressure. The second pressure is higher than the first pressure and is communicated through each of the plurality of fuel injectors. The fuel amplifiers provide for the application of fuel pressure without the need to configure each and every fuel system component for the corresponding higher pressures.

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: A fuel injection device has a two-way control valve driven by a two-position actuator. The control valve directly controls oil pressure in a back pressure chamber to control an injection operation of an injection nozzle. A two-position three-way flow passage switching valve operated by control pressure of the control valve selectively connects a control chamber of a pressure intensifier with a fuel supply passage leading to a pressure accumulator or a pressure release passage leading to a low-pressure system to indirectly control oil pressure in the control chamber. The flow passage switching valve starts a pressure intensifying operation in retard of the injection operation. When pressure is supplied to the control chamber, stoppage of the pressure intensification operation and returning operation of the pressure intensifier do not lag behind the injection operation.

Abstract: The invention relates to a fuel injection valve for intermittent fuel injection into the combustion chamber of internal combustion engines. A needle-shaped injection valve member (34) is arranged in the high-pressure fuel chamber (30) adjacent to the injection valve seat (32), said injection valve member co-operating with the injection valve seat (32) and defining, in a piston-type manner, the cylinder chamber (36) which is connected to the high-pressure inlet (26). The booster piston (28) is controlled by means of the control valve (34) embodied as a flat seat valve, increasing the pressure of the fuel in the high-pressure fuel chamber (30) for an injection, and thus lifting the injection valve member from the injection valve seat. In this way, the injection is carried out with increased pressure.

Abstract: A fuel injector (1) in an internal combustion engine, wherein an intermediate chamber control valve (26) operated by the fuel pressure in a common rail (2) is arranged in a fuel flow passage (25) connecting a two-position switching type three-way valve (8) and an intermediate chamber (20) of a booster piston (17). When the fuel pressure in the common rail (2) is in a high pressure side fuel region, the booster piston (17) is operated by this intermediate chamber control valve (26), while when the fuel pressure in the common rail (2) is in a low pressure side fuel region, the operation of the booster piston (17) is stopped by this intermediate chamber control valve (26).

Abstract: A fuel injection device for internal combustion engines, having a control valve located between high-pressure and low-pressure sides and which opens or blocks the communication of a control chamber with the low-pressure side, and an outlet throttle located between the control valve and the low-pressure side, the control valve having a first valve position, in which the communication of the control chamber with the low-pressure side is blocked, a second valve position, in which the control chamber communicates with the low-pressure side via a first outlet conduit, and a third valve position, in which the control chamber communicates with the low-pressure side via a second outlet conduit having an outlet throttle.

Abstract: A closed nozzle fuel injector is provided which effectively controls the fuel injection flow rate, especially during an initial portion of an injection event, while also permitting accurate control over pilot and/or post injection flow rates at all operating conditions thereby advantageously reducing emissions and combustion noise. The injector includes a rate shaping orifice to restrict fuel flow during an initial portion of an injection event and a rate shaping sleeve mounted for movement to cause a greater flow of injection fuel during a later portion of the injection event. A damping chamber and orifice are also provided to control movement of the rate shaping sleeve.

Abstract: A fuel injection system for an internal combustion engine includes a common rail, a plurality of accumulator injectors, and at least one accumulator controller separate from the accumulator injectors and connected to the common rail. Each accumulator controller includes a solenoid-controlled valve to control the fuel injection operations of one or more accumulator injectors.

Abstract: A fuel injector with a pressure booster supplied with fuel at high pressure. A work chamber of the pressure booster is separated from a differential pressure chamber via a booster piston. The pressure relief and the subjection to pressure of the differential pressure chamber are effected via a switching valve which communicates with the differential pressure chamber via a control line. A pressure chamber on an injection valve member communicates with a compression chamber of the pressure booster via a pressure chamber supply line. The switching valve is embodied as a direct-switching 3/2-way valve, whose valve needle is pressure-balanced and has both a sliding seat and a slide seal.

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: An actuator arrangement for use in a fuel injector of an internal combustion engine includes an inner core (30) comprising a plurality of laminates (30a) and a first outer pole (32) for receiving at least a part of the inner core (30), wherein the inner core (30) and the outer pole (32) together define a first volume (46) for receiving a first electromagnetic winding. An injector is provided in which the actuator arrangement controls a valve arrangement, either a spill valve or a nozzle control valve, or both, so as to control injection by the injector.

Abstract: An internal combustion engine fuel injector (1) has a rod (10) movable along an axis (3) to open/close a nozzle, and a servovalve (7) having a control chamber (23) with a discharge passage (26) which is opened/closed by a shutter (17) movable axially under the control of an electro-actuator (14); the servovalve (7) also has a fixed axial rod (33) having an outer lateral surface (34) through which the discharge passage (26) comes out; the shutter (17) is fitted to the axial rod (33) to slide axially in substantially fluidtight manner, and, when closing the discharge passage (26), is subjected to substantially zero resultant axial pressure by the fuel; and the control chamber (23) is bounded radially by a tubular portion (8) formed in one piece with said axial rod (33).

Abstract: A valve back pressure chamber is provided to exert a back pressure of a first valve needle. Furthermore, a hydraulic pressure passage is provided to extend through the valve back pressure chamber. A valve body is provided to a second valve needle and is driven to connect and disconnect between the hydraulic pressure passage and a fuel tank and thereby to drive the first valve needle. The second valve needle is driven by hydraulic pressure induced by an actuator.

Abstract: A common rail fuel injector comprises a three-way control valve that controls the flow of high-pressure fuel to a fuel cavity for fuel injection. Specifically, when the control valve is transitioning to a first, on position, from a second, off position, high-pressure fuel is provided to both the fuel cavity and to a check control cavity, thereby preventing fuel injection until the control valve seats in the first, on position. Once seated in the first, on position, the control valve only provides high-pressure fuel to the fuel cavity allowing fuel injection to occur. To stop injection, the control valve is moved from the first, on position to the second, closed position. Once again, while the control valve is in the transition location between the two positions, high-pressure fuel is provided to both the fuel cavity and to the check control cavity thereby terminating injection.

Abstract: A fuel injector with a direct needle control for an internal combustion engine, having an actuator, a hydraulic booster, and a nozzle needle guided in a nozzle body and acting on a nozzle needle sealing seat. The hydraulic booster includes a booster piston connected to the actuator and a nozzle needle booster piston connected to the nozzle needle; a booster chamber in the form of an actuator coupler chamber is associated with a pressure surface of the actuator booster piston; and depending on the pressure in the actuator coupler chamber, the nozzle needle is lifted away from the nozzle needle sealing seat, thus initiating an injection. In addition to the actuator booster piston, a control element is provided that is able to execute a stroke motion, is hydraulically coupled to the actuator coupler chamber by means of a first control surface, and is associated with a control chamber by means of a second control surface.

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 three-way valve having a valve chamber with a low-pressure port, a high-pressure port, and a control port is provided. The three-way valve also has a control valve installed in the valve chamber for closing one of the low-pressure port and the high-pressure port. A guide hole communicates with the valve chamber via the high-pressure port. A guide portion is slidably installed in the guide hole and moves together with the control valve. The guide portion further receives a fuel pressure at the high-pressure port in a closing direction of the high-pressure port. The control valve is driven by a piezoelectric actuator to open the low-pressure port and close the high-pressure port. The valve chamber communicates with an oil-accumulating chamber via a by-pass conduit. The oil-accumulating chamber is defined within the guide hole and is located opposite the guide portion from the valve chamber.

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: The present invention provides a fuel injection valve which moves a needle valve (10) via a viscous fluid and a piston (7) by having an actuator (9) move a cylinder (3). The fuel injection valve comprises a sealing member (27) for sealing a gap between the cylinder (3) and piston (7), and a linking hole (29) formed in the piston (7) for connecting two chambers (5, 6) to each other. The size and/or shape of the linking hole (29) is set such that when a force for moving the cylinder (3) or piston (7) at a lower speed than the driving speed of the actuator (9) is generated due to differential thermal expansion between members, the viscous fluid moves between the two chambers (5, 6) through the linking hole (29), and when a force for moving the cylinder (3) at a higher speed than the force generated by the differential thermal expansion is generated by the actuator (9), the viscous fluid cannot pass through the linking hole (29).