Abstract: The present invention provides a fuel injection control apparatus that can suppress variations in fuel injection amounts in a very small fuel injection region. For this purpose, the fuel injection control apparatus includes a fixed injection pulse generator 10 and a drive current interruption unit 31. The fixed injection pulse generator 10 generates a fixed injection pulse having a valve opening timing at which a drive current is supplied to an electromagnetic coil 19 in an electromagnetic fuel injection valve 18 and a first valve closing timing at which the drive current to the electromagnetic coil 19 is interrupted. Within a period in which the fixed injection pulse is generated, the drive current interruption unit 31 determines an electric energy amount of a drive current supplied to the electromagnetic coil in response to a valve opening timing of the fixed injection pulse.

Abstract: A pump includes a cylinder having a working chamber which contains a fluid. A drive system including at least two linear motors which are connected electrically and/or mechanically in parallel moves a piston in the working chamber to bound the working chamber in the cylinder and to pressurize the fluid in the working chamber. A piston rod is connected to the piston and bundles a force applied by the drive system.

Abstract: A pump includes a cylinder having a working chamber which contains a fluid. A drive system including at least two linear motors which are connected electrically and/or mechanically in parallel moves a piston in the working chamber to bound the working chamber in the cylinder and to pressurize the fluid in the working chamber. A piston rod is connected to the piston and bundles a force applied by the drive system.

Abstract: In a fuel pump and method of operation, an infeed for low pressure fuel leads to a pumping chamber where in an intake phase low pressure fuel is drawn into the pumping chamber and in a pumping phase high pressure fuel is delivered to a common rail. An inlet metering valve and an inlet check valve are upstream of the pumping chamber, and a control system closes the metering valve when no fuel is to be pumped to the common rail. The inlet check valve is also opened while the inlet metering valve is closed and no fuel is to be pumped to the rail. The inlet metering valve can include a proportionally controlled piston that produces a variable quantity of feed fuel and is closable for the no-demand condition with a maximum travel that contacts and holds open the inlet check valve.

Abstract: An internal combustion engine includes a plurality of cylinders, a plurality of fuel injection valves, a control chamber provided in each of the fuel injection valves. A control system for the internal combustion engine includes an electronic control unit which is configured to (i) reduce a pressure of the fuel in the control chamber to be lower than a pressure of the fuel in the fuel passage connected to the control chamber, in each of the fuel injection valves, (ii) reduce the pressure of the fuel such that a first pressure difference is equal to or larger than a predetermined pressure difference, so as to move the needle in a direction to open the injection holes, and (iii) reduce the reference pressure by reducing the pressure of the fuel in a second injection valve, such that the first pressure difference after operation is smaller than the predetermined pressure difference.

Abstract: An apparatus and method are presented for repairing damage to the boundary wall between an engine coolant passage and a fuel injector bore in a cylinder head. The method involves removing the fuel injector from the fuel injector bore adjoining the damaged boundary wall and inserting a purpose-built sealant injector tool into the fuel injector bore. The sealant injector tool is dimensionally equivalent to the fuel injector in critical regions so that it conforms to the interior surface of the fuel injector bore. Sealant is injected into the sealant injector tool at high pressure until the sealant flows into the crack between the fuel injector bore and the coolant passage after which the sealant injector tool is removed and the fuel injector reinstalled.

Abstract: Methods are provided for an engine including modifying fuel injection timing based on engine operating conditions. A delay time period calculation may be based on a comparison of a first engine load with a second engine load. Further, a modified injection start time, based on a delay time period, may include injecting fuel during the compression cycle of an engine.

Abstract: A fuel injection controller has terminals which can be connected to the coil of the fuel injector. A first valve-open control portion supplies the valve-opening voltage to the terminals for opening the fuel injector. The first valve-open control portion stops supplying the electric supply to the coil before the fuel injector is positioned at a full-open position. Before the fuel injector is fully closed, a small injection quantity can be obtained. A demagnetization portion forms a demagnetization circuit for demagnetizing the magnetism remaining in the coil. A normal-injection portion controls the fuel injector at full-open position.

Abstract: A system for providing fuel to an internal combustion engine comprises a fuel reservoir for containing fuel for use by the internal combustion engine; a first pump that pumps fuel from a supply tank into the fuel reservoir; and a battery that provides electrical power to the first pump. A control circuit sends signals to selectively run the first pump so as both to minimize a total amount of electrical power consumed by the system and to maintain at least a minimum amount of fuel in the reservoir. Methods for filling a fuel reservoir that contains fuel for use by an internal combustion engine are also provided.

Abstract: A method and device are provided for detecting when a closing point of a hydraulic valve has been reached. The valve has a closing element operated by an electric actuator. A predetermined voltage for closing the valve is applied to the actuator. A profile of a current flowing through the actuator is detected. Based on a first increase in the profile corresponding to the valve being at least partially open, a subsequent decrease in the profile corresponding to the closing element carrying out a movement to close the valve, and a second increase in the profile following said decrease in the profile, a local minimum of the detected current is determined between the decrease and the second increase in the profile. Depending on the local minimum of the detected current, a closing point is then determined which corresponds to a time point of the local minimum of the detected current.

Abstract: A method to reduce engine noise in a multi-cylinder direct injection internal combustion engine. The internal combustion engine includes a high pressure fuel pump having both an inlet valve fluidly connected to a fuel source and an outlet valve typically connected to a pressurized fuel rail. In order to reduce engine noise, especially at low engine speeds, the timing of the opening of either the fuel pump inlet valve or fuel pump outlet valve is varied so that it coincides with the opening of the fuel injectors.

Abstract: A fuel injection system of an internal combustion engine delivers fuel into a fuel rail via a high-pressure pump. The quantity of the delivered fuel is influenced by a quantity control valve operated by an electromagnetic operating device.

Abstract: With reference to FIG. 3, the present invention provides a fluid injector (10) which functions as a positive displacement pump and comprises: a housing (12) in which a piston chamber is formed; a piston (11) which reciprocates in the piston chamber to define therewith a variable volume fluid pumping chamber; a one-way inlet valve (32) which allows flow of fluid into the pumping chamber from a fluid inlet; and a one-way outlet valve (25, 26, 27, 28, 29) which allows flow of fluid out of the pumping chamber to a fluid outlet (31). In operation of the injector the piston (11) cyclically moves to increase volume of the pumping chamber and draw fluid into the pumping chamber via the one-way inlet valve (32) and then the piston moves to decrease volume of the pumping chamber and expel fluid from the pumping chamber via the one-way outlet valve (25, 26, 27, 28, 29).

Abstract: A fuel injector has an injector body and a control rod, which is movable in the injector body along an axis for controlling opening/closing of a nozzle that injects fuel in an engine cylinder; the injector body houses a metering servovalve, provided with a control chamber and with an open/close element of a balanced type, axial sliding of which causes a variation in pressure in the control chamber; the metering servovalve comprises a valve body made of two pieces coaxially coupled to one another via a deformable ring, which defines also a gasket for guaranteeing fluid tightness between the two pieces and maintains in a fixed position a disk on which a calibrated restriction is made.

Abstract: The present disclosure is directed to integrated injector/igniters providing efficient injection, ignition, and complete combustion of various types of fuels. One example of such an injectors/igniter can include a body having a base portion opposite a nozzle portion, and a fuel passageway extending from the base portion to the nozzle portion. A force generator and a first valve are carried by the base portion. The first valve is movable in response to actuation from the force generator to move between closed and open positions. The injector/igniter also includes a second valve at the nozzle portion that is deformable in response to pressure in the fuel passageway to deform between a closed position and an open position.

Abstract: A method for controlling a fuel injection system (10) of an internal combustion engine. Including a high-pressure pump (16) associated with a quantity controlling valve (15) having a solenoid valve (22) electromagnetically actuatable by a coil (21) for supplying fuel, the quantity control valve (15) controlling the quantity of fuel supplied by the high-pressure pump (16) and the coil (21) of the solenoid valve (22) having a first current value applied thereto, in order to close the same for supplying fuel to the high-pressure pump (16), the first current value being reduced to a second current value when the solenoid valve is closing (22), such that the radiation of audible sound arising from the closing of the solenoid valve (22) is at least partially reduced.

Abstract: A fuel injection device for injecting fuel includes an electrical-plug-and-socket connection configured as a modular component. The electrical-plug-and-socket connection includes an electric line region and exactly one one-piece plug contact molding. The plug contact molding surrounds the electric line region, and the plug contact molding forms a part of the outer geometry of the fuel injection device.

Abstract: A control method of an electronic injection fuel feeding system for an internal combustion engine and displaying at least one injector and a non-continuous flow rate fuel pump actuated by a an actuator device; the control method includes the steps of: determining the desired fuel amount which must be injected at each cycle of the internal combustion engine; driving the injector for injecting the desired fuel amount at each cycle of the internal combustion engine; determining an optimal pumping frequency of the actuator device of the fuel pump according to the desired fuel amount which must be injected at each cycle of the internal combustion engine; and actuating the actuator device of the fuel pump at the optimal pumping frequency.

Abstract: Described herein is an electronic-injection fuel-supply system for an internal-combustion engine having at least one injector and a fuel pump; the fuel pump is provided with: a variable-volume pumping chamber; a one-way intake valve; a one-way delivery valve; a mobile piston that integrates within it the intake valve and is coupled to the pumping chamber to vary cyclically the volume of the pumping chamber itself; and an actuator device that impresses a reciprocating motion on the piston and has an electromagnetic actuator for actuating the piston during an intake phase and a spring for actuating the piston during a delivery phase.

Abstract: A high-pressure fuel pump of an internal combustion engine has a fuel injection valve provided on a cylinder. The high-pressure fuel pump is for pumping fuel to the fuel injection valve, and has a pressure chamber, a plunger for pressurizing the fuel in the pressure chamber, a fuel valve provided in the pressure chamber, and an actuator for operating the fuel valve. A control device has means for calculating the drive signal of the actuator so as to realize the variable discharge of the high-pressure fuel pump. The end timing of the drive signal is limited or restricted so that an attraction force of a solenoid coil is not maintained at the bottom dead center of the plunger in case that the required discharge to the fuel pump is less than the total discharge.

Abstract: A method of displacing a pumping assembly. In a first step, a first current is applied in a first direction through a coil assembly to displace a drive assembly from an initial position to cause a first pumping motion. Then, the drive assembly is returned to the initial position to cause a second pumping motion. At some point nearing the end of the second pumping motion, a second current is applied in the first direction through the coil assembly to decelerate the drive assembly before it reaches the initial position. A third current may be applied in a second direction through the coil assembly to cause or assist a return of the drive assembly to the initial position. An apparatus capable of carrying out the method is also disclosed.

Abstract: A fuel injector with an injector body is disclosed which has at least two separate function units that are largely independent of one another. The function units are reversibly joined to one another by a connecting element and at least one positioning pin. The two function units can be produced and tested separately, which greatly simplifies both the production process and maintenance of the fuel injectors and lessens the vulnerability of the fuel injectors to malfunction.

Abstract: The invention relates to a system and method for detecting a closing of a solenoid. The system includes a capacitive charge circuit electrically coupled to the solenoid. The capacitive charge circuit conditions the current flow through the solenoid to increase the current in response to the closing of the solenoid. The invention also relates to a system and method that includes detecting a current through the solenoid and determining a current slope characteristic. The current slope characteristic is a function of the current and time. The method also includes conditioning an electrical characteristic of the solenoid such that the conditioning is in response to a current slope parameter. The current slope parameter defines a change in the current after removal of an electrical charge to the solenoid.

Abstract: With reference to Figure, the present invention provides a fuel injection system for an internal combustion engine which delivers fuel to be mixed with charge air for subsequent combustion in a combustion chamber of the internal combustion engine. The fuel injection system comprises a fuel injector which functions as a positive displacement pump and dispenses in each operation thereof a set quantity of fuel; a mixing chamber into which the fuel injector dispenses fuel; and a gas supply passage for supplying gas to the mixing chamber to entrain the fuel dispensed into the mixing chamber in a flow of gas which passes through the mixing chamber into the combustion chamber. The mixing chamber is connected to the combustion chamber to deliver fuel and gas into the combustion chamber separately from the charge air and a depression in the combustion chamber is used to draw gas through the gas supply passage into the combustion chamber.

Abstract: A reciprocating pump includes a drive section and a pump section. The drive section has a reciprocating coil assembly to which alternating polarity control signals are applied during operation. A permanent magnet structure of the drive section creates a magnetic flux field which interacts with an electromagnetic field produced during application of the control signals to the coil. Depending upon the polarity of the control signals applied to the coil, the coil is driven in one of two directions of movement. A drive member transfers movement of the coil to a pump element which reciprocates with the coil to draw fluid into a pump chamber and expel the fluid during each pump cycle. The pump is particularly well suited to cyclic pumping applications, such as fuel injection systems for internal combustion engines.

Abstract: A method and system for controlling a fuel pressurizing system in a direct-injection, spark-ignition engine is disclosed such that the ticking sound of a solenoid valve in the high pressure pump is disabled at certain engine operating conditions. The fuel pressurizing system includes two pumps in series: a low pressure lift pump and a high pressure pump. Based on an engine operating parameter (speed, load, temperature, fuel delivery rate, as examples) the high pressure fuel pump is disabled when the engine operating parameter is below a threshold. The disablement of the pump is accomplished by turning off the normally-open solenoid valve on the inlet side of the high pressure pump, particularly at low speed and/or low torque conditions, e.g., idle, when the ticking of the injector is particularly noticeable. When the pump is disabled, fuel is supplied to the fuel injectors at lift pump pressure.

Abstract: A reciprocating pump includes a drive section and a pump section. The drive section has a reciprocating coil assembly to which alternating polarity control signals are applied during operation. A permanent magnet structure of the drive section creates a magnetic flux field which interacts with an electromagnetic field produced during application of the control signals to the coil. The coil assembly includes a drive member that drives a plunger assembly having a plunger and a valve stem movably interfitted within the plunger and having a lower poppet head. As the plunger is driven downwardly the plunger contacts the poppet head to drive it into the pump chamber to force the fluid therefrom. There is a gap between the poppet head and the plunger so that the initial downward movement of the plunger closes the gap to gain momentum before it contacts the poppet head and drives it downwardly.

Abstract: This fuel injection control device includes: a fuel injection valve; a piezoelectric element or a solenoid which drives the fuel injection valve; a fuel pump which pressurizes fuel and supplies it to the fuel injection valve; a magnetostrictive element which drives the fuel pump; and a magnetostrictive element driving coil which drives the magnetostrictive element; and the magnetostrictive element driving coil also serves as a voltage elevation coil for a drive circuit which drives the piezoelectric element or the solenoid.

Abstract: The present invention achieves an increase in the amount of vapor that is expelled, stabilized fuel injection and improved starting characteristics in a fuel injection pump. In an electromagnetically driven fuel injection pump 20 which allows fuel to escape into the return passage 5 in the initial region of the pressure-feeding stroke of the plunger 21, and which pressure-feeds fuel into the injection port 33 in the later region of the pressure-feeding stroke, pulse powering of the coil 23 that does not lead to the injection of fuel, i.e., pulse powering which is such that the plunger 21 performs a reciprocating motion through the initial region, is performed when the engine 2 is in an idle operating state, or in a state in which the engine 2 is re-started after being stopped immediately following high-load operation.

Abstract: This invention relates to an electrically operated fuel injection apparatus comprising a fuel inletting device (110), a fuel pumping device (112) and a fuel injecting device (113). Fuel from the said fuel inletting device (110) is pumped by the said fuel pumping device (112) and then is injected out by the said fuel injecting device, wherein the said fuel pumping device (112) includes an operating coil (13), a returning coil (12) and a driven device (114) driven by the magnetic fields of these two coils; the magnetic loop induced by the said operating coil (13) excites the said driven device 9114) so as to inject the fuel by the said fuel injecting device (113), and the magnetic loop induced by the said returning coil (12) excites the said driven device to return back to its original position.

Abstract: The fuel injection system has least one magnet valve for controlling the fuel injection. The magnet valve is triggered by an electric control unit and has a magnet coil, a movable pistonlike magnet armature by which a valve member is movable between at least two positions, a magnetic disk by which the magnet armature is attracted when current flows through the magnet coil, and a cup-shaped capsule into which the magnet armature dips. The magnet armature is guided at least indirectly displaceably via its outer jacket in the capsule.

Abstract: A solenoid-valve-controlled fuel-injection pump for internal combustion engines, in particular diesel engines, has a solenoid valve, whose valve needle separates a high-pressure region from a low-pressure region, i.e. connects the high-pressure region and low-pressure region, in the pump housing, via a valve seat; the injection period being controlled by the opening of the solenoid valve. In addition, a low-pressure compensating piston situated in the low-pressure region is provided in order to compensate for pressure fluctuations in the low-pressure region. The exceptional feature is that the low-pressure compensating piston, which is positioned coaxially to the solenoid-valve needle, takes the form of a component part that is separate from the solenoid-valve needle. This ensures that the solenoid valve is opened unhindered and as rapidly as possible by the opening force exerted on the solenoid-valve needle by the electromagnet.

Abstract: A fuel injection control apparatus and fuel injection method for injecting suitable fuel with quick response to required fuel injection amounts varying with every moment, while improving the energy efficiency, and enabling support for electromagnetic fuel injection apparatus.

Abstract: An internal combustion engine includes an injector that injects fuel into a cylinder. A plunger-type fuel pump pumps the fuel to the injector from a fuel tank. A control system for the fuel pump includes a unit for determining an injection start timing of the injector, and a drive unit for driving the fuel pump for a second predetermined time that starts a first predetermined time earlier than the injection start timing. This control system makes stable combustion possible even when there are pressure variations in the fuel pumped to the injector.

Abstract: An electronically controlled fuel injection device includes a plunger pump, a circulation passage which circulates fuel that has been pressurized in the initial stage of a pressure-feeding stroke, a valve body which blocks the circulation passage in the later stage of the pressure-feeding stroke, an inlet orifice nozzle which allows the passage of fuel whose pressure has been increased in the later stage of the pressure-feeding stroke, an outlet orifice nozzle which is used to circulate some of the fuel that has passed through the inlet orifice nozzle back into the fuel tank, an injection nozzle which injects an amount of fuel equal to the difference between the fuel that has passed through the inlet orifice nozzle and the fuel that has passed through the outlet orifice nozzle, and a control arrangement for controlling the plunger pump in response to the cycle of the engine.

Abstract: A fuel injector system according to the present invention has a housing (52) having a valve assembly (56) disposed therein. A solenoid (54) is also disposed within the housing (52). A valve assembly (56) is disposed between an inlet port (82) and an outlet port (80). The valve assembly has a valve seat (74) having an opening (84) therein. A drive pin (108) extends at least partially through valve opening (84). A stop (78) has a spring (86) thereon. A valve element (76) is urged against the valve opening (84) by spring (86). The drive pin is at least partially coated with a lubricating coating. In the preferred embodiment at least a concave surface (144) of drive pin (108) is coated. In addition, a concave surface (140) of stop (108) is also coated. In addition, spring seat (79) may also be coated with a lubricating coating as well.

Abstract: Pressurized injector actuation fluid, such as oil or fuel, is supplied to high pressure common rail by a fixed displacement fluid pump. Variable delivery from the pump is achieved by selectively spilling pumped fluid through a digital-acting by-pass or spill valve. The by-pass valve is actuated by a momentary electrical signal, which causes internal fluid pressure in the valve to latch it in a closed condition. The digital-acting by-pass valve permits high precision variations in the pump delivery with rapid response times. Unit pump configurations, radial pump configurations, and axial pump configurations are disclosed for both fuel injection applications and non-fuel injection applications. A single pump with plural pistons can be used to power multiple independent hydraulic systems.

Abstract: The invention relates to an apparatus for injecting fuel, having a control valve (16) that has a valve chamber (18). From the valve chamber (18), a high-pressure line (37) leads to the injector; the valve chamber (18) also communicates with a pump chamber (23) for fuel that is at high pressure. The control part of the control valve (16) is actuatable by means of an electromagnet (17). The control valve (16) is coupled with a passive piston (20), which to avoid the pulse change, which acts on the piston (20), is provided with a bore (21).

Abstract: The solenoid valve has a fuel supply conduit, and a ball shutter controlled by an electromagnet and cooperating with a conical seat in the conduit. The conduit has fuel filtration means having a cylindrical wall with a number of openings for preventing particles of dirt from infiltrating between the seat and the shutter, without producing an excessive fall in fuel pressure. The thickness of the cylindrical wall is less than 1 mm, and the width of the openings is less than 0.25 mm.

Abstract: A fuel injector control circuit reduces the number of gates required by arranging high side and low side gates in a matrix. Each coil is selectively activated by activating a unique pair of a high side gate and a low side gate, thus reducing the total number of gates required.

Abstract: A fuel injector having a fuel inlet, a fuel outlet, and a fuel passageway extending along an axis between the fuel inlet and the fuel outlet. The fuel injector includes a body having an inlet portion, an outlet portion, and a neck portion disposed between the inlet portion and the outlet portion. An adjusting tube is disposed within the neck portion of the body. A spring is disposed within the neck portion of the body, the spring having an upstream end proximate to the adjusting tube and a downstream end opposite the upstream end. A filter and an O-ring retainer assembly are disposed proximate the upstream end. An armature having a lower portion is disposed within the neck portion of the body and displaceable along the axis relative to the body. The downstream end of the spring is disposed proximate to the armature, the spring applying a biasing force to the armature. A valve seal is substantially rigidly connected to the lower portion of the armature.

Abstract: The present invention relates to fuel injectors having the ability to inject fuel at multiple pressures during an injection event. Traditional fuel injectors used in common rail fuel injection systems and unit pump fuel injection systems typically did not have the ability to inject fuel at multiple pressures during an injection event. However, engineers have learned that increased control over an injection event can lead to improved emissions by the fuel injectors. Therefore, the present invention utilizes an electronically controlled valve member that can direct the flow of fuel through a fuel injector during an injection event between a relatively restricted passageway and a relatively unrestricted passageway. The present invention finds particular application in both common rail fuel injection systems and electronic unit pump fuel injection systems used in diesel engines.

Abstract: A fuel injection system for internal combustion engines essentially comprises a high-pressure injection pump, supplied with fuel from a low-pressure region, and a magnet valve, embodied as a piston valve and serving to control the injection pump, which magnet valve, in a valve housing, has two coaxial valve chambers, communicating with one another through a valve opening but separable from one another by a valve seat, and an armature chamber. The armature chamber communicates with the inlet side via a pressure conduit, and the (low-pressure) valve chamber communicates with the outlet region of the injection pump. The (low-pressure) valve chamber has a fuel inlet conduit and a fuel outlet conduit. The fuel inlet conduit and fuel outlet conduit, each in the respective portions immediately adjacent to the (low-pressure) valve chamber, have a gradually tapered cross section compared to the cross section of the remaining regions of the fuel inlet conduit and fuel outlet conduit.

Abstract: The present invention relates to engines having common rail fuel injection systems. In traditional common rail fuel injection systems, each fuel injector utilized by the fuel system includes its own solenoid. These individual solenoids must cooperate to ensure that the proper amount of fuel is being injected from each injector at the proper time. It is believed in the art that a reduction in the number of moving or electrical components in the fuel injection system can improve robustness of the system. Therefore, the fuel injection system of the present invention includes fuel injectors that are controlled in operation by a common electronic actuator that is positioned remote from the fuel injectors.

Abstract: A fuel injection device works based on the principle of storage of energy in a solid body and is designed as a reciprocating piston pump with a feeding piston (35, 24) that stores kinetic energy during an almost resistance-free acceleration phase. The stored kinetic energy is abruptly transmitted to the fuel contained in a compression chamber (66), generating a pressure wave for injecting fuel through an injection nozzle. The means that interrupt the resistance-free acceleration phase are designed as a valve with a valve body (50a) and a valve seat (57) shaped on the feeding piston (35, 24). To generate the pressure wave, the valve closes the compression chamber (66) so that the kinetic energy of the feeding piston (35, 24) is transmitted to the fuel enclosed in the compression chamber (66). The valve seat (57) and the valve body (50a) lie at the front end of the feeding piston (35, 24), seen in the direction of injection, and separate the compression chamber (66) from the feeding piston (35, 24).

Abstract: A capacitive actuator is driven with a control signal st. The duration ti of actual actuator actuation is compared with the duration tst of the control signal st. Proper operation is determined, and the actuator is assumed to be operating correctly, if the measured duration ti is within a range determined by the duration tst of the control signal.

Abstract: A driving apparatus for an electromagnetic valve which supplies fuel to an engine comprises a conduction control circuit and a current-limit-value setting circuit. The conduction control circuit turns on and off an FET so that a conduction current flowing through a coil of the electromagnetic valve has a magnitude equal to a predetermined current limit value while a microcomputer is outputting a driving signal to the conduction control circuit. The predetermined current limit value used in the conduction control circuit is set at a first current limit value during a predetermined period starting at a point of time the microcomputer outputs the driving signal. When the predetermined period has lapsed, the predetermined current limit value is switched from the first current limit value to a second current limit value which is smaller than the first current limit value.

Abstract: A high-pressure injection system for internal combustion engines, in particular diesel engines, operates with an actuating force superimposed on a spring force which loads a nozzle needle in the closing direction. The high-pressure injection system operates in such a way that the pressure profile which occurs over the injection stroke of the pump and the resulting injection profile is varied by the actuating force.

Abstract: The solenoid valve has a fuel supply conduit, and a ball shutter controlled by an electromagnet and cooperating with a conical seat in the conduit. The conduit has fuel filtration means having a cylindrical wall with a number of openings for preventing particles of dirt from infiltrating between the seat and the shutter, without producing an excessive fall in fuel pressure. The thickness of the cylindrical wall is less than 1 mm, and the width of the openings is less than 0.25 mm.

Abstract: A fuel delivery system for an internal combustion engine employs a plurality of fuel delivery assemblies for each combustion chamber. The fuel delivery system contains a fluid actuator for each respective combustion chamber or cylinder. Each fluid actuator receives fuel from a source of fuel and directs the fuel to the plurality of fuel delivery assemblies for each combustion chamber. The fluid actuators are under the control of a control system. The control system controls the operation of the fluid actuators to provide desired volumes of fuel at desired flow rates to a combustion chamber from the plurality of fuel delivery assemblies.