Abstract: A piezoelectric fuel injection system and a method of controlling same are provided which include a piezoelectric fuel injector having a piezoelectric element, a power source adapted to provide power to the piezoelectric element to actuate the piezoelectric fuel injector, and a controller adapted to charge the piezoelectric element to an initial voltage to begin said injection event, to decrease the voltage from the initial voltage to an intermediate voltage, and to increase the voltage from the intermediate voltage to a primary voltage to thereby control the injection rate shape. The initial voltage level is at least approximately equal to said primary voltage level and preferably approximately equal to a maximum voltage rating. The initial voltage duration, the intermediate voltage duration and the magnitude of the intermediate voltage can be changed or varied to modify the injection or rate shape.

Abstract: A fuel injection system includes a fuel pressurizer that may be cam actuated. The fuel injection system also includes an electronically controlled spill valve and an electronically controlled needle control valve. The energization of the electronically controlled spill valve closes a fuel pressurization chamber to a drain passage to allow fuel pressure in the fuel injector to build to injection levels. The electronically controlled needle control valve controls whether high or low fuel pressure is applied to a closing hydraulic surface associated with a direct control needle valve. The fuel injection system includes a hydraulic circuitry that allows for fuel injection to occur by either maintaining the electronically controlled needle control valve in a de-energized state, or by de-energizing the same, after fuel pressure within the fuel injector has built to injection levels.

Abstract: A fuel injection system includes a pressure chamber having a displacable piston which can be subjected to pressure via a low-pressure-side pressure booster chamber for compressing the fuel in a high-pressure-side pressure booster chamber to be delivered to an injector. The stroke of the piston is controllable essentially by the pressure in a differential chamber of the pressure chamber and is used to vary the fuel pressure delivered to the injector. Provision is made for enlarging the cross section of the outlet cross section out of the differential chamber of the pressure chamber are provided. The fuel pressure during the injection can be varied. A pressure increase can be simply achieved.

Abstract: A universal injection valve assembly including an injector assembly having a housing, an inlet aperture, an outlet aperture, and a seat located adjacent the outlet aperture. In addition, the injection valve assembly includes a control member movably interconnected to the injector assembly, such that the control member is normally disposed in an operative position relative to the housing. Specifically, the control member is normally disposed in a sealing engagement with the seat of the housing, thereby at least partially defining the operative position. The universal injection valve assembly further includes an actuation assembly having an actuator and an induction mechanism, wherein the induction mechanism is structured to at least temporarily dispose the actuator into an energized state. Additionally, the control member is at least partially comprised of material attracted to the actuator in the energized state, thereby facilitating displacement of the control member from the operative position.

Abstract: A piezoelectric fuel injection system and a method of controlling same, the system including a piezoelectric fuel injector having a piezoelectric element, a power source adapted to provide power to the piezoelectric element to actuate the piezoelectric fuel injector, and a controller adapted to cyclically modulate power provide to the piezoelectric element by the power source during at least a portion of the injection event. The controller cyclically modulates the power between a predetermined first voltage and a predetermined second voltage that is less than the first voltage to control the rate of fuel injected by the piezoelectric fuel injector during the portion of the injection.

Abstract: A fuel injection system includes a pressure booster having a displaceable piston which can be subjected to pressure via a pressure booster chamber on the low-pressure side for compressing the fuel in a pressure booster chamber on the high-pressure side to be delivered to an injector. The stroke of the piston is controllable by the pressure in a differential chamber of the pressure booster and is used to vary the fuel pressure delivered to the injector. Means for continuously variable definition of the inlet cross section to the pressure booster chamber of the pressure booster on the low-pressure side or of the outlet cross section from the differential chamber of the pressure booster are provided.

Abstract: A fuel injector can reduce the smoke emissions generated during low load and decrease NOx during high load. The fuel injector comprises a first accumulator for accumulating a pressurized fuel, a second accumulator for accumulating a fuel having a higher pressure than the pressure of the fuel in the first accumulator, fuel injection valves to which the fuel from the first and second accumulators is supplied and thereby the fuel injection valves are opened, and the fuel is injected, fuel feeding pipes for feeding the fuel accumulated in the first and second accumulators to the fuel injection valves; a first valve mechanism which is provided at the fuel feeding pipe and which opens and allows the flow of the fuel in the first accumulator to the fuel injection valves, a second valve mechanism which is provided at the fuel feeding pipe and which opens and allows the flow of the fuel in the second accumulator to the fuel injection valves, and a control device for controlling the first and second valve mechanisms.

Abstract: The fuel injection device has a high-pressure pump (14) that supplies fuel to a reservoir and is connected to injectors disposed in the cylinders of the engine. A fuel-supply pump delivers fuel from a fuel tank to the suction side of the high-pressure pump. An electrically actuated control valve adjusts the quantity of fuel that the high-pressure pump delivers to the reservoir. The control valve is disposed on the pressure side of the high-pressure pump and can be switched between a first position, in which the pressure side of the high-pressure pump is closed off from a pressure relief region, and a second position, in which the pressure side of the high-pressure pump is connected to the pressure relief region.

Abstract: The fuel injection system has one high-pressure fuel pump and one fuel injection valve for one cylinder of the engine. The fuel pump has a work chamber, and the injection valve has a valve member, and which is movable in an opening direction, counter to the force of a closing spring, by the pressure in a pressure chamber communicating with the pump work chamber; the closing spring is braced between the injection valve member and a displaceable deflection piston which, defines a prechamber that communicates with the pump work chamber. The deflection piston is movable into a storage chamber counter to the force of the closing spring. The prechamber communicates with the pump work chamber via a first throttle restriction, and the pressure chamber of the fuel injection valve communicates with the pump work chamber via a second throttle restriction, circumventing the prechamber.

Abstract: An injector is provided which includes a nozzle valve element, a control volume, and an injection control valve including a control valve member for controlling fuel flow from the control volume so as to control nozzle valve movement. Importantly, the injector includes a nozzle valve lift detecting device for detecting nozzle valve lift and providing a nozzle valve element lift feedback signal. Feedback signals are improved and control valve member oscillations are minimized by positioning a valve seat associated with the control valve member a spaced distance from the control volume, positioning a drain orifice such that the nozzle valve element restricts flow through a drain circuit when in an open position and extending the control valve member from the valve seat to the control volume to form an end wall of the control volume.

Abstract: A turbo-charged internal combustion cylinder assembly includes a combustion chamber, an intake port communicably connected with an intake manifold, and an exhaust port communicably connected with an exhaust manifold. An intake valve is disposed within the intake port, and an exhaust valve is disposed within the exhaust port, the valves facilitating, in an open position, or restricting, in a closed position, gas flow between their respective ports and the combustion chamber. A compressor may be communicably connected to the intake manifold so as to provide pre-combustion gases to, and regulate pressure of the combustion chamber. The exhaust valve may open while the intake valve is closed to exhaust post-combustion gases from the combustion chamber. Alternatively, the exhaust valve may open while the intake valve is open to admit post-combustion gases into the combustion chamber if the combustion chamber pressure is lower than the exhaust port pressure.

Abstract: A fuel injection system has one or more unit fuel injectors or pump-line-nozzle units, corresponding in number to the cylinders, for compressing the fuel. The fuel injection system includes means for generating two different injection pressures during the injection and at least one valve for controlling the injection with a cross sectional control. The fuel injection with the aid of the unit fuel injector or a pump-line-nozzle unit can be achieved over a wide rpm range with great precision.

Abstract: A cam for driving a high-pressure fuel pump has a cam profile that is asymmetric for the suction stroke and the ejection stroke. The cam profile is set so that the cam angle for the ejection stroke is greater than the cam angle for the suction stroke. Therefore, even when the cam drive shaft is rotating at a constant speed, the duration of the ejection stroke becomes longer than the duration of the suction stroke. That is, the changing speed of the capacity of a pressurizing chamber becomes less during the ejection stroke than during the suction stroke.

Abstract: A common rail fuel injection apparatus includes a piston that increases the injection pressure, and a chamber that controls the position of the piston so as to control the injection pressure. An input constriction that sets an amount of flow of the fuel that enters the control chamber, and an output constriction that sets an amount of flow of the fuel that exits from the chamber are formed. The input constriction is connected to a common rail by a valve. By opening and closing the valve, the injection pressure of the fuel injected from an injector is changed. Therefore, the injection pressure of fuel injected from the injector can be changed as requested without a need to process high precision component parts.

Abstract: A hydraulically-actuated unit fuel injector of the intensifier type is provided with two independently operable active control valves. A selectively actuable fuel pressure control valve is disposed on the hydraulic actuation fluid side to control the fuel pressure actuation process and provide a window of injection opportunity wherein the fuel pressure is maintained at high pressure. A selectively actuable timing control valve is disposed on the high pressure fuel side to provide precise control of injection timing events and duration, such as start of injection, end of injection, timing of interruption and duration of interruption, which all may occur during a single injection event within the window of opportunity. Both control valves are independently controlled to prevent reverse motion of the intensifier piston and plunger during dwell or interruption of injection while maintaining the full injection pressure.

Abstract: By setting a switching timing of switching means that connects either one of a high pressure fuel source and a low pressure fuel source to an injector earlier than a point of time when an injector finishes a high pressure fuel injection, leak fuel or return fuel is reduced and an engine load is reduced and therefore mileage is improved.

Abstract: Controlling fuel injectors to create varying injection rates and injection rate shapes typically involves using multiple control valves to control fuel pressure and check valve opening pressure independently. The fuel injector of this application uses a single control valve positioned between a fuel supply passage and a tip supply passage. The control valve has at least three positions. In a second position allowing a first maximum fuel injection rate and allowing a second maximum fuel injection rate in a third position.

Abstract: The fuel injection apparatus has one fuel pump for each cylinder of the engine, which pump has a pump piston, driven by the engine in a reciprocating motion, that defines a pump work chamber, which communicates via a line with a fuel injection valve, disposed on the engine separately from the fuel pump, which valve has an injection valve member, by which at least one injection opening is controlled, and which is movable in the opening direction, counter to a closing force, by the pressure generated in the pump work chamber, and at least one first electrically triggered control valve is provided, by which a communication of the pump work chamber with a relief chamber is controlled, and which is disposed near the fuel pump.

Abstract: A pump assembly and method for an internal combustion engine includes a high-pressure pump for pressurizing oil used to actuate fuel injectors or other devices, a hydraulic inlet throttle valve, a three-way valve for alternatively connecting the inlet throttle valve to output pressure or to the sump and a solenoid responsive to signals from an electronic control module for shifting the three-way valve.

Abstract: A fuel injection system is provided which includes a source of high pressure fuel, a low pressure fuel reservoir, and at least one fuel injector which has an injector body that defines a nozzle chamber, a needle control chamber, a needle control vent, a fuel inlet, and a nozzle outlet. A high pressure line extends between the source of high pressure fuel and the fuel inlet. A low pressure line extends between the low pressure fuel reservoir and the needle control vent. A needle control valve is positioned in the injector body and includes a poppet valve member with a first position in which the needle control chamber is fluidly connected to the fuel inlet but closed to the needle control vent. The poppet valve also has a second position in which the needle control chamber is closed to the fuel inlet but open to the needle control vent.

Abstract: End of injection rate shaping can be attained by controlling the flow rate into a check control cavity. Specifically, a flow control valve allows the check control cavity to vent at a first flow rate and to pressurize at a second slower flow rate. By pressurizing at a slower rate, end of injection does not occur as quickly, allowing injection pressure to decrease before injection is terminated.

Abstract: A nozzle supply valve is positioned in the nozzle supply passage of a fuel injector, and is constructed to generate a boot shaped rate trace mechanically. The goal of the concept is to restrict the flow area during the first boot step and release the flow area restriction in the second step. During the first stage of injection, the flow to the nozzle only goes through a restricted orifice. When the line pressure is high enough to overcome the valve movement pressure spring preload, the nozzle supply valve moves to an unrestricted position, and the boot shaped rate trace is formed. Since this boot shape rate trace is generated mechanically, it can be combined with fuel injectors having a direct control needle valve in order to get different rate traces including, ramps, squares, pilots, posts and other split injections.

Abstract: A fuel injector includes a spool control valve, a plunger which moves in a fuel pressure chamber between retracted and full stroke positions. The fuel injector may include a spill port for spilling fuel from the fuel pressure chamber, the spill port being open at the start and closed by the translating motion of the plunger to delay the start of injection. The fuel injector chamber may further include a control port which is closed at the start of plunger motion and is opened by the plunger to connect the pressure chamber to a needle back chamber to bias the needle valve closed. The needle back chamber becomes isolated from the pressure chamber by further movement of the plunger and includes a pressure control passage to allow the pressure therein to decay upon control port closure, thereby effecting split injection or rate shaping.

Abstract: A rail connection assembly includes an outer rail connection tube having a rail connection outlet, a component having a substantially centrally located bore that is fixed to the outer rail connection tube remote from said rail connection outlet, and a piston adapted for movement between a first position and a second position, with the second position being remote from said bore. A nipple having a predetermined cross section and extends from the piston and is slidably movable into and remote from said bore when the piston is moved between the first and second positions, respectively. A fluid communication path exists between the bore and the rail connection outlet. This provides a pilot injection of fuel when the piston moves into an intermediate position between the first and second positions and a full injection of fuel when the piston reaches the second position.

Abstract: An electromagnetic control valve has a passage for conducting fluid. An electromagnetic actuator generates an electromagnetic force. A main valve body opens and closes the passage in accordance with the electromagnetic force generated by the electromagnetic actuator. A bypass is formed in the main valve body. A sub valve body opens and closes the bypass in accordance with the electromagnetic force generated by the electromagnetic actuator. The electromagnetic force generated by the electromagnetic actuator is adjusted such that the sub valve body is opened and closed while the main valve body closes the passage.

Abstract: A fuel injector for an internal combustion engine has an injector housing having a pressure releasable control chamber for a vertical stroke movement and an annular chamber, an injector body closeable by the annular chamber, an inlet connectable to a high pressure collecting chamber and connected to and emptying into the annular chamber, an injection nozzle having a nozzle inlet and a nozzle chamber, with the nozzle inlet opened or closed by a sealing surface, a hydraulic spring associated with the injector body and including a control element impinged with high pressure via a volume of the hydraulic spring and via the inlet.

Abstract: A variable delivery fuel supply device capable of improving linearity of discharge characteristics with respect to a rotational angle of a cam and reducing abrasion of the cam.

Abstract: To prevent the sticking of the valve body of an electromagnetic valve under idling conditions or under non-injection conditions in a control device of common rail fuel injection system of an engine wherein the fuel supplied from a feed pump (6) is pressurized to high pressure by a high-pressure pump (3) and the quantity of fuel supply to this high-pressure pump (3) is adjusted by an electromagnetic valve (7) whose degree of opening is controlled in accordance with a duty signal, the control frequency of the duty signal is altered to a lower frequency (&lgr;l) when an operating condition such that the degree of opening of the electromagnetic valve (7) is constant is detected. In this way, the energy or amplitude per current wave flowing in the electromagnetic solenoid (39) can be made larger, so making it possible to produce minute vibrations of the valve body (41). Sticking of the valve body (41) can thereby be prevented.

Abstract: A method and system for injecting fuel in at least two different high fuel pressures via injectors into a combustion chamber of an internal combustion engine. The higher fuel pressure being stored in a central pressure reservoir, the lower fuel pressure is generated individually locally for each injector, at all times during the injection event by diversion of the higher fuel pressure. The diversion being activatable or deactivatable via a multi-way valve. To that end, a corresponding fuel injection system with a central pressure reservoir for storing the higher fuel pressure has a local diversion unit for each injector by means of which the lower fuel pressure can be generated dissipatively from the higher fuel pressure, and the local diversion unit has a multi-way valve for activating and deactivating the diversion, respectively. In this way, an improved metering of the lower fuel pressure can be achieved.

Abstract: In a pressure increasing type injector, a fuel pressure increasing chamber is communicated via a pressure relief passage, a recessed portion, a communication hole, a hollow portion and a bypass passage with a pressure release portion. A ball valve disposed within the recessed portion interrupts the communication between the recessed portion and the pressure relief passage at the start of fuel injection, and communicates the recessed portion with the pressure relief passage at the end of the fuel injection. Consequently, an injection ratio is increased gently at the start of the injection, and the fuel within the fuel pressure increasing chamber flows out therefrom to a pressure release portion when the valve is closed. Accordingly, an injection port can be closed rapidly and therefore the injection ratio is lowered abruptly.

Abstract: In a method for operating a Diesel engine with a pump-line-nozzle injection system, which allows the pressure level to be raised in the lower and intermediate engine speed ranges in relation to a predetermined maximum permissible injection pressure without this maximum permissible injection pressure being exceeded in the upper engine speed range by providing an injection pump designed to deliver the desired fuel injection pressure at low and intermediate engine speeds and including a pressure relief valve in the fuel injection line permitting limiting of the fuel injection pressure at higher engine speeds.

Abstract: A fuel injection valve for internal combustion engines with a valve member that is guided so that the valve member can move axially in a bore of the valve body. The valve member, on an end oriented toward the combustion chamber of the engine, has a conical valve sealing surface with which the valve member cooperates with a conical valve seat surface at the closed, combustion chamber end of the bore of the valve member. The conical valve sealing surface on the valve member is divided into two regions that have different cone angles, at the transition of which a transition region is formed. The transition region is delimited by an upstream and a downstream valve sealing edge, where the difference between the cone angle of the transition region and the cone angle of the valve sealing surface is smaller than the difference between the cone angle of the downstream region and the cone angle of the valve sealing surface (inverse seat angle differential).

Abstract: A fuel system for an outboard motor includes a plurality of high-pressure pumps and a conduit circuit with a multi-branched passage connecting the engine's combustion chamber(s) to the fuel supply. At least two sections of the conduit circuit may be connected together at a point downstream of the high-pressure pumps. The high-pressure pumps also may be driven by a common pump drive unit, which may be designed to drive the pumps in a manner providing a generally uniform flow of fuel.

Abstract: The invention relates to a unit injector system for internal combustion engines, in particular diesel engines, having a pump element for subjecting fuel in a pump chamber to high pressure, having an injection element for injecting the pressurized fuel into the combustion chamber of the engine, and having a control valve, which opens and closes a connection between the pump chamber and a low-pressure chamber. To make a preinjection possible, a throttle device (13) is disposed in the connection between the pump chamber and the low-pressure chamber, and there is a flow through the throttle device as a function of the position of the control valve.

Abstract: The invention relates to a method for shaping the injection pressure course (27) in injectors, which are used for instance in injection devices of injection systems in motor vehicles. The injection device includes a pump part (1) and an injection nozzle part (2). The pump part (1) and injection nozzle part (2) communicate with one another via a high-pressure line (3). Control valves (8, 10) which are triggered by means of an actuator (9) are contained in the pump part (1). By the triggering by means of the actuator (9), injection parameters during the preinjection phase (28), pressure buildup phase (29) and main injection phase (30) are determined.

Abstract: A hydraulic control device which may be used in a number of applications, including with a fuel injector, includes a control valve having a first and a second independently shiftable valve member, the control member being configurable to define a plurality of actuating fluid flow paths for controlling hydraulic flow therethrough. A fuel injector includes the aforementioned control valve. A method of hydraulic control includes a number of steps, including independently controlling the shifting of two valves in a control valve assembly to selectively control the flow of actuating fluid to an actuator.

Abstract: A controller (8) of an accumulator fuel-injection apparatus opens a selector valve (5) for injection rate switching for a short time between auxiliary injection and main injection, the selector valve controlling high-pressure fuel supply from a high-pressure accumulator (3) to a fuel passage (10a) on the downstream side of a check valve (32), whereby a fuel pressure higher than an auxiliary injection pressure and lower than a main injection pressure is formed in the fuel passage on the downstream side of the selector valve (5). By opening, in this state, an on-off valve (7) for injection timing control to start the main injection, a proper pressure higher than the auxiliary injection pressure and lower than the subsequent main injection pressure is established in the initial stage of main injection, improving fuel economy and exhaust-gas characteristic.

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 injector for an internal combustion engine, having a valve member which is axially displaceable in a guide bore of a valve body, has two guide areas with which it is displaceably guided in the guide bore, a first upper guide area being provided on the send of the valve member facing away from the combustion chamber and a second lower guide area being provided in an area of the valve member near the combustion chamber, a lower guide area separating an annular clearance which is formed between the valve member shaft and the wall of the guide bore and is connected to a high-pressure fuel inlet channel is separated from a lower pressure space opening onto the valve seat face when the fuel injector is closed, and opening this connection during the opening stroke movement of the valve member, and having a connecting throttle cross section between the annular clearance and the lower pressure space. This throttle cross section is designed as a throttlebore.

Abstract: A fuel injector comprising a valve needle which is slidable within a bore and engageable with a seating to control fuel delivery through first and second outlet openings. The valve needle is moveable between a closed position and first and second fuel injecting positions. The fuel injector further comprises a fuel supply passage for supplying fuel under pressure to the bore and a control chamber which is arranged to receive fuel from the fuel passage, in use. The valve needle is acted upon in use by a force due to fuel pressure within the control chamber. An actuator arrangement controls fuel pressure within the control chamber, and a damping means are provided for damping movement of the valve needle away from the seating into the first or second fuel injecting position. The supply passage for fuel may be provided with a restricted flow passage which serves to limit the amplitude of pressure waves within the supply passage.

Abstract: When two fuel shots such as the main and anchor fuel shots are closely coupled, the controller is operable to determine a total main and anchor fuel quantity, a main shot duration, and anchor delay. The total main and anchor fuel quantity is determined by subtracting a pilot shot fuel amount from the governor fuel output, and a sensor senses a rail pressure. If a triggering condition is met, preferably a main shot fuel amount being less than or equal to a minimum main shot fuel amount, the anchor duration is determined from a map using the main shot duration, anchor delay, rail pressure, and total main and anchor fuel quantity as factors for setting the anchor duration.

Abstract: A high pressure fuel injection system for an internal combustion engine having a high pressure pump for delivering fuel to a fuel injector. The pressure output of the pump is sensed and is controlled to provide appropriate fuel pressure to the fuel injector for the given running condition. In addition, a release passage is formed that intersects the high pressure pump at a point intermediate the ends of its stroke and which is controlled by a control valve for releasing pressure to further provide pressure control. Even if fully opened due to failure, the release valve will not preclude the generation of pressure sufficient to run the engine.

Abstract: A fuel injection valve for high-pressure injection of fuel from a high-pressure reservoir into a combustion chamber of an internal combustion engine, especially a diesel engine, is described. The fuel injection valve has a magnet valve by means of which the fuel pressure can be either relieved (injection position) or built up (closing position) in a control chamber via a throttle having at least one throttle conduit segment defined by conduit walls. According to the invention, the throttle conduit segment is embodied substantially in the form of a variable aperture, or a variable throttle aperture.

Abstract: An electromagnetic control valve has a passage for conducting fluid. An electromagnetic actuator generates an electromagnetic force. A main valve body opens and closes the passage in accordance with the electromagnetic force generated by the electromagnetic actuator. A bypass is formed in the main valve body. A sub valve body opens and closes the bypass in accordance with the electromagnetic force generated by the electromagnetic actuator. The electromagnetic force generated by the electromagnetic actuator is adjusted such that the sub valve body is opened and closed while the main valve body closes the passage.

Abstract: A hydraulically actuated fuel injector has an electronically controlled actuator that moves an actuation valve member. The actuator can position the actuation valve member at one position to cause pressurization of fuel in a nozzle chamber for fuel injection, and at another position to hydraulically bias a check to halt fuel injection while maintaining full fuel pressure in the nozzle chamber indefinitely.

Abstract: A diesel injector is provided with a variable-volume flow-subtraction chamber containing a spring-loaded flow-subtraction piston. The chamber is connected to the pump chamber or related lines by passages that include a flow-subtraction control orifice. A space behind the piston is vented to fuel supply ducting that is associated with the system. A flow-subtraction control orifice controls the subtractive flow of fluid into the flow-subtraction chamber in predefined proportion to the flow of fluid through the combined nozzle orifices, such proportion being that between the cross-sectional area of the control orifice and the combined cross-sectional areas of the nozzle orifices. Such proportion of flow is maintained until the subtractive flow ends as the piston reaches a stop at its fully open position, whereupon the reduced-rate-of-injection phase ends and the main injection phase then occurs.

Abstract: A hydraulically actuated fuel injector includes an injector body that defines a fuel nozzle outlet and a plurality of passages, including high pressure actuation fluid passages, and low pressure drainage and vent passages. A piston with at least one hydraulic surface is movably disposed between retracted and advanced positions along a stroke distance in a piston bore defined by the injector body. When acted upon by high pressure actuation fluid, the piston, in cooperation with a plunger, advances from its initial retracted position a certain stroke distance before it uncovers and exposes an actuation fluid flow enhancement annulus. Exposure of the piston hydraulic surface(s) to the additional flow capacity provided via the actuation fluid flow enhancement annulus yields higher piston and plunger acceleration rates, resulting in sustained high piston acceleration and a higher peak fuel injection pressure and flow rate.

Abstract: A fuel injection system for a diesel engine operating at retarded fuel injection timing includes a fuel cam configured to increase a fuel injection pressure and decrease a fuel injection duration, thereby improving fuel atomization and combustion in a plurality of engine cylinders and improving an indicated efficiency of the engine and reducing exhaust emissions. The fuel cam is oriented in a phase relationship with a compression stroke top-dead-center position to accommodate the retarded fuel injection timing and to optimize an engine brake efficiency and performance.

Abstract: This accumulating fuel injection apparatus is provided with a needle valve 6 adapted to open and close an injection nozzle 11 having injection ports 14 in a lower end portion thereof, a balancing chamber 5 formed in a casing 2 so as to apply a fuel pressure to a head portion of the needle valve 6, a supply passage including a slit 10 and used for supplying a fuel from a fuel supply port 19 to the balancing chamber 5, a discharge passage 20 comprising an orifice for discharging the fuel from the balancing chamber 5, and a solenoid valve 22 adapted to open and close the discharge passage 20, the lift of a valve disc 26 of the solenoid valve 22 is controlled by a lift control means comprising a stopper 28 the position of which is controlled by a lift control mechanism 23.

Abstract: An apparatus for producing a variable volumetric flow in a fuel feed system includes a high-pressure pump having at least one inlet, at least one cylinder, at least one piston each moveable in a respective cylinder, and a shaft driving the at least one piston. A metering device is disposed in the at least one inlet of the high-pressure pump, is synchronized with the shaft and feeds a variably meterable volume of fuel to the at least one cylinder during each revolution of the shaft. Metering is performed by varying an angle between opening and closure of the at least one inlet.