Abstract: A fuel system for an internal combustion engine includes a nozzle, a fuel pump, a spill valve assembly, and a pumping control unit. The spill valve assembly includes a first spill valve and a second spill valve fluidly in parallel between a plunger cavity in the fuel pump and a low pressure space. A pumping control unit commands closing of the first spill valve and then the second spill valve to adjust the spill valve assembly to start pressurization in the fuel pump, and commands opening the first spill valve to end pressurization in the fuel pump. A pumping duration is determined based on a timing of the commanded closing of the second spill valve and a timing of the commanded opening of the first spill valve.

Abstract: A blended fuel injection control method may include a cold-starting determination step in which a controller determines whether a cold-starting condition is satisfied on the basis of output values that can be obtained by a vehicle; a detection step in which the controller detects the content of ethanol in blended fuel of gasoline and ethanol when determining the cold-starting condition is satisfied; and a first injection control step in which the controller controls the blended fuel to be injected selectively in one of a Multi-Point Injection (MPI) mode, an MPI & GDI mode combining MPI and Gasoline Direct Injection (GDI) modes, and a GDI mode in accordance with the content of ethanol in the blended fuel until an engine RPM reaches an early peak RPM in engine-cranking.

Abstract: A fuel delivery injector includes a housing, an end cap including an inlet port fluidly coupled to a cavity to direct fuel vapor and liquid fuel into the cavity and an outlet port fluidly coupled to the cavity to direct fuel vapor and liquid fuel out of the cavity, a magnetic assembly fixedly positioned within the cavity, and a pumping assembly including a bobbin and a piston. A return spring is coupled to the pumping assembly to bias the pumping assembly to a home position and a valve assembly including a biasing spring is positioned between an inlet chamber and an outlet chamber. The liquid fuel entering the housing through the inlet port flows from the inlet port to the cavity and fuel vapor entering the housing through the inlet port is directed through a conduit to the outlet port.

Abstract: A fuel delivery injector includes a housing, an end cap including an inlet port fluidly coupled to a cavity to direct fuel vapor and liquid fuel into the cavity and an outlet port fluidly coupled to the cavity to direct fuel vapor and liquid fuel out of the cavity, a magnetic assembly fixedly positioned within the cavity, and a pumping assembly including a bobbin and a piston. A return spring is coupled to the pumping assembly to bias the pumping assembly to a home position and a valve assembly including a biasing spring is positioned between an inlet chamber and an outlet chamber. The end cap includes a protrusion extending therefrom and terminating at an end face, the end face proximate the magnetic assembly and the protrusion is configured to redirect fuel vapor toward the outlet port.

Abstract: A multi-valve fuel injection system comprising an electronic unit pump for outputting high pressure fuel; a low pressure fuel pipe for inputting fuel into the plunger cavity of the electronic unit pump; a fuel supply cam for propelling the movement of the plunger of the electronic unit pump to produce high pressure fuel; at least two electronically controlled fuel injectors for injecting fuel; high pressure fuel injection pipe connecting the electronic unit pump and the electronically controlled fuel injectors for transporting the high pressure fuel outputted form the electronic unit pump to the electronically controlled fuel injectors, respectively, for controlling the electronic unit pump and the opening and closing of solenoid valves in the fuel injectors. The fuel injection system can achieve large range fuel injection and high circulating response. Also disclosed is a fuel injection method for the multi-valve fuel injection system.

Abstract: A fuel injection system for an internal combustion engine is provided which works to correct the pressure of fuel, as measured by a pressure sensor, using a pressure change corresponding to a change in quantity of the fuel in a common rail within a pressure change compensating time Tp to determine a pump discharge pressure Ptop. This compensates for an error in determining the pump discharge pressure Ptop which arises from propagation of the pressure of fuel from a pump to the pressure sensor. The pressure change compensating time Tp is the sum of a time T1 elapsed between sampling the output of the pressure sensor before a calculation start time when the pump discharge pressure is to start to be calculated and the calculation start time and a time T2 required for the pressure to transmit from the outlet of the pump to the pressure sensor.

Abstract: Disclosed is a fuel injection mechanism having a horizontal control surface formed within a plunger for regulating the start of fuel injection. The horizontal control surfaces are formed within one or more of the two opposed ridges formed within the plunger defining a recessed channel there between. The horizontal control surfaces of the ridges regulate the opening and closing of the ports formed within the bushing of the injector. The horizontal control surfaces contribute to reduced wear and provide for accurate timing and fuel quantity delivery.

Abstract: A fuel pump for a direct-injection system provided with a common rail comprises a pumping chamber defined in a main body. A piston is mounted in a sliding manner inside the pumping chamber to cyclically vary volume of the pumping chamber. A suction channel is connected to the pumping chamber and regulated by a suction valve. A delivery channel is connected to the pumping chamber and regulated by a delivery valve. A flow-rate-adjustment device is mechanically coupled to the suction valve to keep, when necessary, the suction valve substantially open during pumping of the piston and includes a control rod that is coupled to the suction valve and an electromagnetic actuator that acts on the control rod and has a one-way hydraulic brake that is integral to and substantially slows movement of the control rod.

Abstract: A high pressure fuel pump control system for an internal combustion engine includes a fuel injection valve provided in a fuel common rail and a high pressure fuel pump for feeding fuel by pressure to the fuel injection valve. The high pressure fuel pump includes a pressurized chamber, a plunger for pressurizing fuel in the pressurized chamber, a discharge valve provided in a discharge passage, an intake valve provided in an intake passage, and an actuator for operating the intake valve. The control system includes a means for calculating a drive signal for the actuator to make a discharge amount or pressure of the high pressure fuel pump variable. The means reduces pressure in the common rail by opening the discharge valve to return the fuel in the fuel common rail to the pressurized chamber when a requirement for reducing the pressure in the fuel common rail is made.

Abstract: A fuel injection pump having a separable plunger includes a separable plunger of which outer circumference is slide coupled to an inside of the a such that a lower portion thereof is supported by an upper portion of a main plunger to enable upward and downward slide movement in association with the main plunger, wherein an injection timing control spiral step of which upper surface is formed in a spiral shape, is protrudingly formed on the outer circumference thereof and a fuel passage is formed on one side of the outer circumference thereof including the injection timing control spiral step and an elastic member having a lower portion elastically supported by the separable plunger and an upper portion inserted within the barrel to be supported by an upper surface of the barrel.

Abstract: One embodiment is a fuel system for an internal combustion engine including a fuel pump having a fuel pump gear operable to drive the fuel pump to pressurize fuel. The fuel pump gear is offset relative to engine top dead center by a predetermined angle to reduce a sound or noise. The offset can be determined by selecting the minimum sound produced over a range of offsets or operating conditions.

Abstract: A vibration reducing system for an engine is disclosed. The vibration reducing system includes at least one pumping member movable through a plurality of pumping strokes during an engine cycle. The vibration reducing system also includes a controller in communication with the at least one pumping member, the controller being configured to identify a vibration characteristic of the engine. The controller also is configured to adjust the displacement of fuel during at least one of the plurality of pumping strokes based on the vibration characteristic.

Abstract: The fuel supply system of an internal combustion engine includes an electronic control unit (ECU) for transferring the engine from a state in which a high-pressure fuel pump does not deliver any pressurized fuel to a state in which the high-pressure fuel pump begins to deliver the pressurized fuel by gradually varying an output period of a drive signal for controlling opening/closing behavior of a solenoid valve while monitoring changes in fuel pressure detected by a pressure sensor, and for estimating a mounting error between angular mounting positions of the high-pressure fuel pump and a pump actuating cam with reference to a rotation signal from a state of the solenoid valve drive signal when a change in the fuel pressure has been detected. The solenoid valve drive signal is corrected based on the value of the mounting error estimated by the ECU.

Abstract: A vibration reducing system for an engine is disclosed. The vibration reducing system includes at least one pumping member movable through a plurality of pumping strokes during an engine cycle. The vibration reducing system also includes a controller in communication with the at least one pumping member, the controller being configured to identify a vibration characteristic of the engine. The controller also is configured to adjust the displacement of fuel during at least one of the plurality of pumping strokes based on the vibration characteristic.

Abstract: Noise and vibrations associated with a common rail fuel system drive linkage are reduced by synchronizing a high pressure common rail supply pump with engine operation. This may be accomplished by selecting a linkage associated with a desired ratio of engine speed to pump speed along with selecting a number of pump plungers and cam lobes that results in synchronizing action of the pump with engine combustion events. In particular, a pattern of pumping events per engine cycle repeats during each engine cycle. In a more sophisticated version, the pattern of pumping events per engine cycle includes a sub-pattern of pumping events that repeats an integer number of times each engine cycle, where the integer number equals the number of engine cylinders.

Abstract: In a method for operating an internal combustion engine (10) equipped with a piston pump as a high-pressure pump (18), which is driven by a drive shaft (28) of the engine (10), in which the high-pressure pump (18) delivers fuel from a low-pressure region (16) to a high-pressure side (38) and a quantity control valve (44) sets the quantity of fuel delivered by the high-pressure pump (18), the acoustic emission of the high-pressure pump is reduced by virtue of the fact that the high-pressure pump (18) functions in a two-point operation, alternating between full delivery for individual or successive piston strokes and idle delivery for individual or successive piston strokes and, when the pressure falls below a lower pressure threshold, the full delivery is activated until an upper pressure threshold is reached.

Abstract: A control servo valve is housed inside the casing of an internal combustion engine fuel injector, and has an actuator, a control chamber communicating with a fuel inlet and with a fuel outlet passage, and a shutter movable along an axis by the actuator between a closed position and an open position to close and open the outlet passage respectively; the servo valve also has a fixed axial rod interposed between the actuator and the control chamber; the outlet passage comes out through an outer lateral surface of the axial rod; and the shutter is defined by a sleeve which slides axially on the outer lateral surface, and, in the closed position, closes the outlet passage so as to be subjected to a zero axial resultant force by the pressure of the fuel.

Abstract: A fuel pump for use in an internal combustion engine comprises a pump housing provided with a plunger bore, a pumping plunger which is movable within the plunger bore by means of a cam drive arrangement to perform a pumping stroke to pressurise fuel within a pumping chamber and a cam follower arrangement interposed between the cam drive arrangement and the pumping plunger so as to transmit a drive force of the drive arrangement to the pumping plunger. The cam follower arrangement includes a timing advance piston for advancing or retarding the timing of the pumping stroke, and control means for controlling the timing advance piston so as to advance or retard the timing of the pumping stroke. The timing advance piston is provided with a groove on its outer surface for receiving fluid, thereby to provide a centralising force to the timing advance piston, in use.

Abstract: Disclosed is a fuel injection mechanism for regulating the volume of fuel injected into a cylinder comprising a selectively detachable helix ring configured to be removably affixed to an outside diameter of a plunger. The selectively detachable helix ring includes a ridge that has at least one helix angle. The helix angle is associated with a throttle position of the mechanism.

Abstract: An electroinjector is provided for controlling fuel injection in an internal-combustion engine. The electroinjector includes an electroactuator, an injection nozzle, and a pin, which is movable along an opening stroke and a closing stroke for opening/closing the nozzle under the control of the electroactuator and according to the supply pressure of the fuel into the electroinjector. A first electrical command and at least a second electrical command, which are sufficiently close to one another as to displace the pin with a profile of motion without any discontinuity in time, and such as to cause the pin to perform a first opening displacement and, respectively, a second opening displacement, are supplied to the electroactuator.

Abstract: An advance arrangement for use in controlling timing of fuel delivery by a fuel pump for use in an engine comprises an advance piston (12) which is slidable within a first bore (14) and which cooperates, in use, with a cam arrangement of a fuel pump to adjust the timing of fuel delivery by the pump. A surface associated with the advance piston (12) is exposed to fuel pressure within a first control chamber (38). The pressure of fuel within the first control chamber (38) is controlled by means of a servo piston (24) which is slidable within a further bore (22) provided in the advance piston (12). The servo piston (24) is responsive to speed dependent fuel pressure variations within a servo control chamber (37), thereby to permit adjustment of the timing in response to engine speed.

Abstract: A direct fuel injection/spark ignition engine control device is configured to enable compression stroke injection when the fuel pressure is low at startup and immediately after startup, and to reduce the wall flow and amount of HC exhaust. When the catalyst requires warming, fuel is injected in the compression stroke, and the fuel injection timing in the compression stroke is set in accordance with the fuel pressure. When the fuel pressure is low, the fuel injection timing injects fuel in the first half of the compression stroke. The fuel injection timing is delayed as the fuel pressure increases until the optimum fuel injection timing is reached.

Abstract: A diesel locomotive engine having a piston with a unique bowl geometry. The bowl is defined in part by a center portion having a partial spherical shape. A cone portion (22) is located adjacent the central portion. An annular toroidal surface (24) is connected to the cone portion (22) and is defined by a toroidal major diameter (Dtm) and a toroidal minor radius (Rtm). A crown rim (26) is connected to the annular toroidal surface (24) and to an upper flat rim face of a sidewall.

Abstract: After initial combustion at the time of engine startup under very low temperature conditions, a fuel-injection start time point and a fuel-injection end time point are restricted to a period of time during which smoldering of an ignition plug is less prone to occur, to warm up the inside of a cylinder and increase engine speed. Thereafter, a fuel injection period is adjusted by gradually elongating it by reducing the restriction on the injection start time point and the injection end time point each time the engine speed exceeds a predetermined value in the course of the increase in the engine speed. In this way, the engines are made to reach a state where the engine can operate in a self-sustaining manner, before smoldering of the ignition plugs progresses after the initial combustion at the time of the engine startup under very low temperature conditions.

Abstract: A pump for a fuel system is disclosed. The pump has a housing defining at least one pumping chamber, and a plunger. The plunger is movable to draw a fluid into and displace the fluid from the at least one pumping chamber. The pump also has a metering valve and a controller. The metering valve has a valve element movable to selectively meter fluid drawn into the at least one pumping chamber. The controller is configured to receive an indication of a desired discharge characteristic and reference a first map to determine an inlet opening area corresponding to the desired discharge characteristic. The controller is also configured to reference a second map to determine a position of the metering valve corresponding to the determined inlet opening area, and to send a control signal to the metering valve indicative of the determined position.

Abstract: The high-pressure pump (7) comprises a number of pumping elements (18) actuated in reciprocating motion through corresponding suction and delivery strokes. Each pumping element (18) is provided with a corresponding intake valve (25) in communication with an intake pipe (10) supplied by a low-pressure pump (9). Set on the intake pipe (10) is an on-off solenoid valve (27) having a reduced flow rate substantially of the same order of magnitude as the maximum amount of fuel that can be injected by an injector (5). The solenoid valve (27) is controlled in a chopped way in synchronism with an intermediate part (32) of the suction stroke of each pumping element (18).

Abstract: Each of paired centrifugal weights are interlockingly connected to an advancing spring, which is interlockingly connected to a temperature-sensing operation device. When cold-starting the engine, the advancing spring is maintained extensible based on a state of the temperature-sensing operation in which the temperature-sensing operation device senses a temperature to operate. This advancing spring exerts a spring force, which pushes and widens the paired centrifugal weights to an advancing position. While the engine is warm, the advancing spring is held contracted based on another state of the temperature-sensing operation device, in which the temperature-sensing operation device senses a temperature to operate, so that the spring force of the advancing spring does not act on the paired centrifugal weights. A shape memory spring composed of a compression coil spring is used for the temperature-sensing operation device.

Abstract: In accordance with one aspect of the present technique, a method of reducing pollutant emissions from a compression-ignition engine is provided. The method includes adjusting timing of fuel injection into a combustion chamber of a piston-cylinder assembly of the compression-ignition engine. The method of adjusting timing of fuel injection includes indexing a drive mechanism intercoupling a camshaft to a crankshaft by at least one tooth away from a standard position. The method of adjusting timing of fuel injection further includes adjusting a pre-stroke of a plunger of a fuel injector assembly.

Abstract: A control servo valve (8) is housed inside the casing of an internal combustion engine fuel injector (1), and has an actuator (9), a control chamber (13) communicating with a fuel inlet (5) and with a fuel outlet passage (22), and a shutter (35) movable along an axis (3) by the actuator (9) between a closed position and an open position to close and open the outlet passage (22) respectively; the servo valve (8) also has a fixed axial rod (29) interposed between the actuator (9) and the control chamber (13); the outlet passage (22) comes out through an outer lateral surface (30) of the axial rod (29); and the shutter (35) is defined by a sleeve which slides axially on the outer lateral surface (30), and, in the closed position, closes the outlet passage (22) so as to be subjected to a zero axial resultant force by the pressure of the fuel.

Abstract: In an energy-saving high-pressure fuel supply control device for sucking a low-pressure fuel via a flow rate control valve and supplying high-pressure fuel acquired by pressurizing the sucked fuel to a fuel rail, at a time point that is logically decided from a bottom dead center and at which the pressure of the high-pressure fuel rises to a pressure to hold closing of the flow rate control valve, energization of the flow rate control valve is ended to restrain energization energy to the flow rate control valve. The time point when the energization of the flow rate control valve is ended is deviated toward lag side in advance by a time that causes deviation of the bottom dead center of the plunger toward the lag side from the original bottom dead center.

Abstract: A fuel injector in injection systems for internal combustion engines having a valve body containing a control chamber that can be pressure-relieved and can be acted on with fuel via an inlet throttle and can be pressure-relieved via an outlet throttle. A first actuator can actuate a closing element. The valve body is connected to a holding body that has a nozzle body connected to it, which encompasses an injection valve element. In order to relieve the pressure in the control chamber, an additional, second outlet throttle is provided, whose closing element can be actuated either by an additional actuator or as a function of the power supply to a double-switching actuator.

Abstract: A modified pump follower device (2) and method of retarding injection timing of EMD-type unit injectors by a desired amount of crank degrees includes the steps of providing a modified pump follower (2) whose plunger engagement location, also known as t-slot (7), varies depending on the desired amount of retarding. Specifically, the modified pump follower (2) has a t-slot (7) which has a predetermined distance t? on the modified pump follower (2), as compared to conventional pump followers having a predetermined distance t, such that the t-slot (14) is closer to the top face (9) of the pump follower (2). The difference in spacing between the original timing t and the retarded timing t? is r, which is an amount equal to the amount of retardation, in linear units, that corresponds to the desired amount of retardation in crank degrees.

Abstract: A fuel injection pump comprises: a barrel formed with a main port 39 and a sub port 36a; a plunger 32; and a CSD 30 including an injection-advancing actuator 38 which operates a piston 35 for opening or closing sub port 36a so as to change an injection timing. Plunger 32 is moved to connect or separate sub port 36a and main port 39 to and from a fuel compression chamber 17. The barrel is further formed with at least one exclusive overflowing sub port 36b constantly opened regardless of the operational state of the piston 35.

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: Fuel injection equipment is provided which realizes characteristics of fuel injection proper for all over the operation range of an engine, can further reduce nitrogen oxide(NOx) emission, and is high in mechanical durability. The fuel injection equipment for an internal combustion engine comprises an injection pump having a plunger part and a fuel passage equipped with a main electromagnetic valve, a fuel supply part for supplying the fuel to the fuel injection pump, a fuel injection pipe for sending the fuel to an injection nozzle part, and a secondary electromagnetic valve attached to an overflow pipe for returning to said fuel supply part the redundant fuel not to be injected from said unit injector, wherein an orifice is attached to said overflow pipe.

Abstract: A method for the direct injection of fuel into an internal combustion engine, wherein a high-pressure pump with a variable flow rate supplies the fuel to a common rail, which in turn supplies the fuel to a series of injectors; the flow rate of the high-pressure pump is controlled by choking each pump stroke by varying the closure time of an intake valve of said high-pressure pump; the mechanical actuation of the high-pressure pump is timed so that each injection interval is located at the beginning of a respective choking action; and each pump stroke is choked by at least an angular interval having a duration no shorter than that of the injection intervals irrespective of the quantity of fuel to be supplied to the common rail in such a way that the injection phase of each injector always takes place when the high-pressure pump is not pumping fuel to the common rail.

Abstract: A method of controlling fuel injection timing in a compression ignition engine including at least one cylinder. The method includes monitoring a parameter indicative of a commanded operating speed of the engine corresponding to an engine throttle notch and monitoring a parameter indicative of the actual operating speed of the engine. When the commanded engine speed exceeds the actual engine speed, the fuel injection timing for the engine may be advanced to reduce emissions.

Abstract: In a method for forming a fuel/air mixture in a direct-injection internal combustion engine with a fuel injection nozzle arranged in each cylinder, a closing member of the fuel injection nozzle is moved from a closed position to an operating position by means of a control device at different speeds until the operating stroke is reached, in order to obtain optimum combustion, and a uniform concentration of the fuel particles introduced with increased impulse into the combustion chamber is achieved providing for the formation of a swirl with a constant symmetry and uniform distribution of fuel in the swirl.

Abstract: An internal combustion engine fuel injector has a casing defining a nozzle; and a shutter pin having an axis, and housed in axially sliding manner inside the casing to close the nozzle by virtue of a control rod. The pin and the control rod are connected by a connecting device, which has an axial seat carried by the pin, and a head interposed between the axial seat and the control rod, and which engages the axial seat to transmit to the pin a resultant of forces directed solely along the pin axis.

Abstract: A control a control for an injector includes an energizing device actuated by a fluid pressure during an injection event to provide a monitoring voltage. The control unit is used with an injector and is capable of monitoring the variables of the injector such as opening and closing times of the spool valve by using a pressure of the working fluid. The control unit can control the opening and closing of the injector by determining the opening times based on a generated voltage.

Abstract: Systems and methods for reducing engine emissions in a locomotive are presented. In an embodiment, a fuel injector or a fuel injection pump of a fuel injection mechanism includes a plunger with an upper helix whose angle changes between points on the plunger that correspond to an idle throttle position and a full throttle position. As such, injection timing is optimized, and engine emissions are reduced.

Abstract: A method and apparatus for reducing the smoke emissions of a railroad locomotive during throttle notch changes. For certain throttle notch increases the present invention advances the engine timing angle and controls application of the load at the new throttle notch position, according to certain predetermined parameters. These strategies, when used together or separately, minimize visible smoke during transient operation.

Abstract: The fuel injection system has one high-pressure fuel pump (10) with a pump work chamber (22) and one fuel injection valve (12), communicating with the pump work chamber, for each cylinder of the engine. The fuel injection valve (12) has a first injection valve member (28), by which at least a first injection opening (32) is controlled, and which is movable in an opening direction (29) counter to a closing force by the pressure generated in the pump work chamber (22).

Abstract: A radial piston pump used for producing high fuel pressure in fuel systems of internal combustion engines, in particular in a common rail injection system includes a housing with at least one cylinder and a drive shaft is supported in the housing and having at least one cam section. A stroke ring is disposed encompassing the cam section a piston contained in each cylinder is supported against the stroke ring. A possibility for adjusting the delivery quantity of the radial piston pump is achieved in that an adjusting ring is disposed between the cam section and the stroke ring and the internal opening of this adjusting ring is eccentric in relation to the outer contour and can be rotated around the central axis of the internal opening into a desired angular position in relation to the cam section.

Abstract: A fuel injection device (26) for an internal combustion engine (10) has a fuel inlet (40) and a fuel outlet (42). A plunger (58) is operable within a fuel pumping chamber (50) for forcing pressure-amplified fuel to open and pass through an outlet control valve (56) at the outlet. A (“fast-acting”) control valve (64) operates in timed relation to the engine cycle to allow control fluid from an oil rail (34) to force valve (56) closed when fuel is not to be injected and to disallow control fluid from forcing valve (56) closed when fuel is to be injected. A (“slow-acting”) control valve (72) is selectively operable in timed relation to the engine cycle to disallow control fluid from acting on plunger (58) when fuel is not to be injected, but allow control fluid to act on the plunger to force injection when control valve (72) is disallowing control fluid from forcing control valve (56) closed.

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: Systems and methods for reducing engine emissions in a locomotive are presented. In an embodiment, a fuel injector or a fuel injection pump of a fuel injection mechanism includes a plunger with an upper helix whose angle changes between points on the plunger that correspond to an idle throttle position and a full throttle position. As such, injection timing is optimized, and engine emissions are reduced.

Abstract: Systems and methods for reducing engine emissions in a locomotive are presented. In an embodiment, a fuel injector or a fuel injection pump of a fuel injection mechanism includes a plunger with an upper helix whose angle changes between points on the plunger that correspond to an idle throttle position and a full throttle position. As such, injection timing is optimized, and engine emissions are reduced.

Abstract: A novel injection-pump plunger used in a unit injector for an EMD-type diesel engine has its upper (cut-off) control edge shaped to retard start of injection at full power from what it is with standard plungers, and to provide in a straight-line manner a relatively small increase in retardation from full load to idle. In a preferred form, the plunger has one or more steps in its upper (cut-off) control edge, the step or steps being formed between adjacent segments of the edge that are associated with different load points. A method of improving emissions/fuel-economy of EMD diesel engines comprises using prototype injection-pump plungers shaped within certain parameters, assessing their performance, selecting new patterns of timing based on the assessment, making new prototype plungers and assessing them, and repeating the steps of selecting, making and assessing if and as required until an assessment indicates compliance with applicable performance standards.

Abstract: An electroinjector is provided for controlling fuel injection in an internal-combustion engine. The electroinjector includes an electroactuator, an injection nozzle, and a pin, which is movable along an opening stroke and a closing stroke for opening/closing the nozzle under the control of the electroactuator and according to the supply pressure of the fuel into the electroinjector. A first electrical command and at least a second electrical command, which are sufficiently close to one another as to displace the pin with a profile of motion without any discontinuity in time, and such as to cause the pin to perform a first opening displacement and, respectively, a second opening displacement, are supplied to the electroactuator.