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

Abstract: In an injection nozzle for a fuel injection system, the opening stroke of the nozzle needle is to be limited selectively, so that different injection cross sections can be employed. To that end, the injection nozzle is provided with a nozzle body, a nozzle needle displaceable in the nozzle body, two groups of injection ports, which are uncovered as a function of an opening stroke of the nozzle needle, a piston that is connected to the nozzle needle, a stop chamber in which the piston is disposed and which is provided with an outlet, and a control valve that can open and close the outlet of the stop chamber, as a result of which the stroke of the piston in the stop chamber and thus the opening stroke of the nozzle needle can be selectively limited.

Abstract: A fluid dosing device for a pressurized liquid is disclosed, which comprises a chamber (35) which is supplied with pressurized liquid by means of a liquid supply line (17, 19); a valve needle (9) which is guided through the chamber (35), the first end section of said valve needle being able to be lifted and the second end section thereof forming a valve in conjunction with a valve seat disposed on the housing (3). Metal bellows (33) are provided as a leadthrough element for the first end section of the valve needle (9). The metal bellows seal the chamber in said region in a tight manner. A throttle point (37, 39) is provided between the valve needle (9) and the inner wall of the chamber between the metal bellows (33) and the mouth (18) of the liquid supply line (17) leading into the chamber.

Abstract: A fuel injector for injecting pressure fuel in a combustion chamber of an internal combustion engine has an injector housing, an inlet connectable with a high pressure collecting chamber, a nozzle inlet line, a 2/2-way valve for opening and closing the nozzle inlet line, a control chamber in which a pressure change occurs, at least one first ball valve positioned at a side of the control chamber, at least one second ball valve positioned at a side of the inlet, and a guide element movable in the housing, the first and second ball valve being positioned opposite to one another and associated with the movable guide element.

Abstract: A technique is provided for enhancing fluid flow in an outwardly opening nozzle assembly. A flow enhancement assembly is provided adjacent an exit from an outwardly opening poppet to provide desired spray characteristics. The flow enhancement assembly includes converging and diverging passages and a plurality of ports to form a spray.

Abstract: A fuel injector for delivering fuel to a combustion space comprises a valve needle which is movable within a bore provided in a nozzle body and which is engageable with a seating to control the supply of fuel from the bore. The injector further comprises a return flow passage for permitting fuel to escape from the bore to a low pressure drain upon initial movement of the valve needle away from its seating. The injector may include a cover member which defines, together with the nozzle body, a part of the return passage for fuel through which fuel flows, in use, to reduce the temperature of the nozzle body.

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

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

Abstract: Disclosed is a fuel injection valve having at least two valve body parts, which each contact one another at a respective contact face and pressed against one another perpendicular to the contact face by a clamping device. An inflow conduit for fuel formed in both valve body parts passes through the contact faces, and a high fuel pressure prevails in it. At least one radially widened portion is embodied in the inflow conduit, near the contact face of at least one valve body part, so that this radially widened portion, as a result of the fuel pressure in the inflow conduit, undergoes an expansion in the axial direction. As a result, the region of the contact face surrounding the inflow conduit is pressed against the contact face of the contacting valve body part, so that the contact pressure of the contact faces increases, whereby the inflow conduit is thus better sealed off, and the force of the clamping device can be reduced.

Abstract: A technique is provided for homogenizing fluid flow in an outwardly opening nozzle assembly. A cavity is provided in a fluid flow passage adjacent a spray exit of an outwardly opening poppet to dampen fluid flow variances prior to spray formation at the spray exit. Accordingly, the spray formed at the spray exit has a substantially uniform distribution of fluid droplets.

Abstract: A valve for controlling fluids is embodied with a piezoelectric actuator (3) for actuating a valve member (2) that on one end has a valve head (7), forming a valve closing member, that cooperates with a seat (8) provided on the valve body (6) for opening and closing the valve (1). On a side of the piezoelectric actuator (3) remote from the valve member (2), a hydraulic chamber (21) is provided, which communicates, via at least one hydraulic line (23), with a bore (5) of the valve member (2) that is sealed from the piezoelectric actuator (3), and into which bore a piston (20) connected to the piezoelectric actuator (3) can plunge; the hydraulic chamber (21) is embodied as a hydraulic spring, which with its spring force on the piston (20) connected to the piezoelectric actuator (3) act as the prestressing element and the tolerance compensating element. The valve is intended in particular as a component of a fuel injection valve.

Abstract: A fuel injector nozzle is disclosed which solves a long-standing problem in the industry of reducing polluting engine emissions. The nozzle has a needle which alternately blocks and leaves open spray holes for delivering fuel to the combustion chamber. The needle is received in a cavity where the injector needle seats. Machining the seat of the cavity causes a sac at the nozzle tip where the unburned fuel causes the polluting emissions. Minimizing the sac volume minimizes the polluting emissions. The present invention discloses a nozzle formed with a seat having an apex located at the bottom of a sac. The design of the present minimizes the sac volume and the sac volume is closer to zero volume than any prior design.

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

Abstract: A nozzle assembly for fuel injection in an internal combustion engine comprising a nozzle tip with a hollow interior defining a fuel chamber. The nozzle tip has at least one spray orifice opening to an outer surface on the nozzle tip, and a valve member at least partially disposed within the nozzle tip. The valve member is moveable between a first position in which the valve member contacts an upper valve seat to prevent fluid communication of fuel from the fuel chamber to the at least one spray orifice, and a second outward position in which the valve member contacts a lower valve seat to allow fluid communication of fuel from the fuel chamber to the at least one spray orifice. The valve member is directly electrically actuated, preferably by a solenoid. Further, the valve member is biased in the closed position and the valve member is pressure balanced when high pressure fuel in present in the fuel chamber.

Abstract: A high pressure gaseous fuel injector for injecting natural gas or other gaseous fuels at high pressures (eg. 300 to 700 psig more or less) into combustion engines for improved efficiency, better performance and reduced environmental emissions. The fuel injector includes an outer cartridge housing and a universal valve cartridge mounted therein. Spring washers are used to urge the valve cartridge against a metal O-ring supported by the outer cartridge housing.

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

Abstract: A valve actuating device is provided which may be employed in fuel injectors for automotive internal combustion engines. The valve actuating device includes an actuator, a large-diameter piston displaced by said actuator, a small-diameter piston operating a valve, a displacement amplifying chamber filled with working fluid to amplify and transmit displacement of the large-diameter piston to the small-diameter piston, and a drain passage. The drain passage communicates with the displacement amplifying chamber through a pinhole for draining the working fluid within the displacement amplifying chamber, thereby enabling the pressure in the displacement amplifying chamber to be released in order to ensure the movement of the small-diameter piston when the valve actuating device is started.

Abstract: The fuel injection valve of the present invention is constituted such that a needle valve 5 and a movable core 4 are movably disposed in an axial direction in the inside of a body 1. Here, a fixed member 8 which the movable core 4 approaches at the time of closing the valve is disposed in the body 1, and a gap is formed between the movable core 4 and the fixed member 8 at the time of closing the valve. When fuel remaining in the gap between the movable core 4 and the fixed member 8 is pressurized according to the movement of the movable core 4 to the valve closing side, a squeezing portion SB1 is disposed at a portion which constitutes a passage for the fuel extruded from the gap. At the time of closing the valve, a squeezing reaction force (reaction force against the squeezing-out force or pushing-out force generated at the time of pressurizing a liquid and squeezing a liquid through the gap) is generated on the movable core 4.

Abstract: A method of controlling the injection rate and injection pressure of an electromagnetic fuel injector assembly having a pressure balanced control valve including a solenoid and a valve member subject to the pressures developed by the injector and actuated by the solenoid to close the valve member against the biasing force of a spring. The control valve is supported in a valve bore in the injector body. The valve bore includes a relieved portion. The method includes the step of providing a first level of current to the solenoid for moving the valve member from an open to a closed position allowing the pressure in the injector to rise, providing a reduced level of current to the solenoid at preselected times during the injector event to unbalance the forces acting on the valve member thereby slightly unseating the valve member to regulate the injection pressure and injection rate of the fuel injector and ending current to the solenoid thereby moving the valve member to its open position.

Abstract: An outwardly opening fuel injector comprises a valve needle movable within a bore provided in a nozzle body and engageable with a seating to control the supply of fuel from the bore. The valve needle is biased towards its seating and is moveable outwardly of the bore to move the valve needle away from its seating. The fuel injector comprises a sleeve member which is moveable with the valve needle, the valve needle and the sleeve member together defining a chamber for fuel such that, in use, fuel pressure within the chamber serves to dilate the sleeve member to reduce fuel leakage from the injector. A surface associated with the valve needle may be engageable with an additional seating defined by the bore to limit outward movement of the valve needle within the bore.

Abstract: A high pressure gaseous fuel injector for injecting natural gas or other gaseous fuels at high pressures (eg. 300 to 700 psig more or less) into combustion engines for improved efficiency, better performance and reduced environmental emissions. The fuel injector is powered by hydraulic signals from an electrohydraulic valve. The fuel injector includes an outer cartridge housing and a universal valve cartridge mounted therein. The cartridge comprises an activator body and a valve body secured together, and the valve body has a gas valve slidable therein. The stroke of the valve is adjustable by controlling the size of shims in the valve body assembly, thereby providing a universal valve cartridge that can be easily adapted to differing fueling requirements for models and sizes of engines. The valve body includes a spring chamber between upper and lower valve guides.

Abstract: A fuel injector for delivering fuel to a combustion space comprises a valve needle which is movable within a bore provided in a nozzle body and which is engageable with a seating to control the supply of fuel from the bore. The injector further comprises means for permitting fuel to escape from the bore to a low pressure drain upon initial movement of the valve needle away from its seating. The injector may include a cover member which defines, together with the nozzle body, a part of a return passage for fuel through which fuel flows, in use, to reduce the temperature of the nozzle body.

Abstract: An injector for a fuel injection system is provided with an injector housing in which a piezoelectric stack is located and with a valve housing connected with the injector housing in which a valve closing device with a jet needle is displaceably located. The valve closing device can be actuated by the piezoelectric stack. The valve closing device can be reset by a return device. A hydraulic following amplifier is located between the piezoelectric stack and the jet needle of the valve closing device. The amplifier has a displacement piston actuated by the piezoelectric stack. A control piston located downstream from the displacement piston and increases the displacement travel. A working piston that actuates the jet needle and increases the actuating force.

Abstract: A high pressure gaseous fuel injector for injecting natural gas or other gaseous fuels at high pressures (eg. 300 to 700 psig more or less) into combustion engines for improved efficiency, better performance and reduced environmental emissions. The fuel injector is powered by hydraulic signals from an electrohydraulic valve. The fuel injector includes an outer cartridge housing and a universal valve cartridge mounted therein. The cartridge comprises an activator body and a valve body secured together, and the valve body has a gas valve slidable therein. The stroke of the valve is adjustable by controlling the size of shims in the valve body assembly, thereby providing a universal valve cartridge that can be easily adapted to differing fueling requirements for models and sizes of engines. The valve body includes a spring chamber between upper and lower valve guides.

Abstract: A fuel injector has an actuator for generating a lifting movement and a lift translator filled with a hydraulic medium and deformable in the lifting direction, for transferring the lifting movement of the actuator to a valve needle, provision being made for a compensating chamber for the hydraulic medium, the compensating chamber being connected to an interior space of the lift translator via a throttle opening and enclosed by an elastic casing. Thus, temperature-related quasistatic deformations of actuator, lift translator, and/or valve needle can be compensated for by an exchange of the hydraulic medium between the interior space of the lift translator and the compensating chamber, while the comparatively fast lifting movements of the actuator are transmitted to the valve needle essentially without damping.

Abstract: A fuel injection valve for internal combustion engines, having a valve member that is displaceable axially outward counter to a restoring force in a bore of a valve body. On an end toward the combustion chamber, the valve member has a closing head. The closing head protrudes from the bore and forms a valve closing member and on a side toward the valve body has a valve sealing face. The valve closing member cooperates with a valve seat face, disposed on a face end toward the combustion chamber of the valve body. The valve closing member at least one injection opening on the closing head. The injection opening originating at a pressure chamber and outlet opening being covered, in the closing position of the valve member, by the valve body and being uncovered upon an outward-oriented opening stroke. A two-stage hydraulic stroke stop, which limits the opening stroke of the valve member and is embodied as a hydraulic damping chamber with a relief line that can be opened.

Abstract: The injection valve has a control valve with a control chamber in which a closing member is disposed. The closing member is pressed against a corresponding sealing seat by a pressure (e.g. fuel pressure) in the control chamber. The closing member merges into a rod that passes through a drain hole and is connected to a spring plate. The spring plate is preloaded against the housing by a compression spring in such a way that the closing member is pressed against an associated sealing seat. The closing member can be raised from the sealing seat by an actuator piston which rests against the spring plate.