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In the method according to the invention, the inlet pressure and the inlet cross section of the fuel pre-stored in the pump work chamber is constant, and it is solely the opening duration of an inlet valve which is electrically regulated. In addition, a shift in the instant of supply onset controlle

In the method according to the invention, the inlet pressure and the inlet cross section of the fuel pre-stored in the pump work chamber is constant, and it is solely the opening duration of an inlet valve which is electrically regulated. In addition, a shift in the instant of supply onset controlled in accordance with operating characteristics is attained by means of a variation in the return-flow fuel quantity. A shift in the instant of supply onset, which is undesired when there is a change in the quantity of fuel to be injected, is prevented by means of a simultaneously-effected correction of the return-flow fuel quantity. A fuel injection apparatus suitable for performing the method has, as the inlet valve, a magnetic valve which determines the quantity of fuel pre-stored in the pump work chamber. The rotary position of the pump piston is variable in order to shift or correct the instant of supply onset by means of an adjacent device actuated by an electromechanical adjustment element. An electric control device emitting the metering pulse and a control pulse is connected with a set-point transducer and an adjustment-path transducer of the adjustment device. The apparatus can be equipped with either a pump/nozzle or a normal piston injection pump supplying the injection nozzle via a pressure line, or with a distributor injection pump.

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1. A method of injecting fuel by a fuel injection assembly into an internal combustion engine, in particular a Diesel engine, having a fuel supply with an instant of onset, an inlet line, an inlet valve, a piston injecting pump with a pump work chamber, a relief means, a fuel metering means, an elec

1. A method of injecting fuel by a fuel injection assembly into an internal combustion engine, in particular a Diesel engine, having a fuel supply with an instant of onset, an inlet line, an inlet valve, a piston injecting pump with a pump work chamber, a relief means, a fuel metering means, an electrical regulating means, and a fuel return means the steps including: metering a quantity of fuel to be injected with the fuel metering means, before the engine compression stroke, injecting the metered quantity of fuel into the engine with the piston injection pump, regulating the flow of fuel in the inlet line with the inlet valve having an opening duration, which leads to the pump work chamber, pre-storing the metered quantity of fuel in the pump work chamber, fixing the end of fuel supply by relieving the pump work chamber with the relief means, wherein metering of the quantity of fuel prestored in the pump work chamber with the fuel metering means occurs while: keeping the pressure of the fuel constant in the inlet line; and keeping the inlet cross-section of the inlet valve constant; and wherein regulating the supply of fuel to be injected into the internal combustion engine occurs by regulating the opening duration of the inlet valve with the electrical regulating means, correcting the quantity of fuel in the fuel return means in accordance with the metered fuel quantity during changing of the quantity of fuel prestored in the work chamber. 2. A method as defined in claim 1, the steps also including: shifting the instant of fuel supply onset in accordance with engine characteristics by changing the quantity of fuel in the fuel return means, re-aspirating the quantity of fuel in the fuel return means; wherein only the quantity of fuel to be injected is metered by means of the opening duration of the inlet valve. 3. A method as defined in claim 1, the steps also including: preventing the re-aspiration of the quantity of fuel in the fuel return means; and replacing the quantity of fuel in the fuel return means with a second fuel quantity; metering the quantity of fuel to be injected and the second fuel quantity by means of the opening duration of the inlet valve, and shifting the instant of fuel supply onset in accordance with engine characteristics by changing the second fuel quantity. 4. A method as defined in claim 1, wherein the inlet line is connected to the pump work chamber through an inlet opening, and wherein the assembly also includes a control member, the steps including: opening the inlet opening; controlling the instants of opening and closing of the inlet valve with the control member during the opening duration of the inlet opening. 5. A method as defined in claim 1, wherein the inlet line is connected to the pump work chamber through an inlet opening, and wherein the assembly also includes a pump piston, the steps including: opening the inlet opening; controlling the instant of opening and closing of the inlet valve with the pump piston during the opening duration of the inlet opening. 6. A method as defined in claim 5, the steps including: keeping the pump piston in an inner dead center position; controlling the inlet valve opening duration only after the end of an intake stroke while the pump piston is at inner dead center. 7. A method as defined in claim 1, the steps also including: moving the pump piston to end pre-storage of fuel in the pump work chamber; correcting the opening duration of the inlet valve by only varying the instant of opening of the inlet valve; fixing the instant of closing of the inlet valve at time which is subsequent to the end of pre-storage of fuel in the pump work chamber. 8. A method as defined in claim 1, the assembly also including a temperature sensing means, the steps also including: correcting the inlet pressure according to temperature with the temperature sensing means. 9. A method as defined in claim 1, the assembly also including a temperature sensing means, the steps also including: correcting the opening duration of the inlet valve according to temperature with the temperature sensing means. 10. A method as defined in claim 1, the assembly also having a detecting means the steps also including: detecting a rapid shift in the instant of supply onset; correcting the opening duration of the inlet valve during a transitional period, such that when the instant of supply onset shifts to a later time the fuel quantity is reduced, and such that when the instant of supply onset is towards an earlier time, the fuel quantity is increased. 11. An apparatus for regulating fuel injection in an internal combustion engine having a fuel supply pump which provides an inlet pressure, in particular a Diesel engine, having a piston injection pump which includes: a piston; a pump work chamber; an adjusting device connected to the piston injection pump to alter the end of a piston supply stroke; a diversion opening in the wall of the piston injection pump; a control face on the piston which controls the diversion opening; an inlet line provided with an inlet valve; a pressure regulating valve connected to regulate the inlet pressure; wherein the inlet valve is a magnetic inlet valve and is connected to the pump work chamber to regulate a fuel quantity which is prestored in the pump work chamber; the piston injection pump also including: an electromechanical adjusting element connected to actuate the adjusting device; a pulse generating means which is connected to generate a control pulse to the electromechanical adjusting element to alter the piston position; a set-point transducer which generates set-point information to the adjusting device; an adjustment-path transducer which generates adjustment path information to the adjusting device; an electrical control device connected to generate a signal to the electromechanical adjusting element such that the electromechanical adjusting element is dependent on the electrical control device, and wherein the electrical control device is connected to the set-point transducer to receive the set-point information and to the adjustment path transducer to receive the adjustment path information, and wherein the electrical control device is also connected to generate a metering pulse to the magnetic inlet valve to determine duration of the magnetic valve opening. 12. An apparatus as defined in claim 11, wherein the injection pump includes a pump cylinder in which the piston is axially and rotationally guided, and wherein the apparatus includes: the inlet line, having an inlet opening, connecting the pump work chamber to the fuel supply; a first control edge on the piston, which operates to close the inlet opening during a supply stroke and having a second oblique control edge which acts as an axial limitation for the control face and is positioned such that the diversion opening is opened at the end of the supply stroke to release a return flow fuel quantity, and is closed after a predetermined portion of the intake stroke which permits re-aspiration of the return flow fuel quantity, wherein the magnetic inlet valve is a multi-way valve which in open position connects the inlet line to the pump work chamber with a constant inlet cross section, and in a closed portion blocks the pump work chamber from the inlet line, and wherein opening duration of the magnetic valve determines the quantity of fuel to be injected into the engine. 13. An apparatus as defined in claim 12, wherein the adjusting device has a regulating rod which engages the electromechanical adjusting element, wherein the piston is arranged such that a variable rotary position of the piston determines the return-flow fuel quantity, and controls supply onset and wherein the adjustment path transducer is connected to the piston to detect piston rotary position. 14. An apparatus as defined in claim 12, further including a line section which connects the magnetic inlet valve to the inlet opening, and wherein the inlet opening is embodied as a throttle bore having a cross section less than the magnetic inlet valve cross section and less than the line section cross section. 15. An apparatus as defined in claim 13, further including a line section which connects the magnetic inlet valve to the inlet opening, and wherein the inlet opening is embodied as a throttle bore having a cross section less than the magnetic inlet valve cross section and less than the line section cross section. 16. An apparatus as defined in claim 12, also including a constant pressure chamber wherein the piston has a jacket face, a portion of which closes the inlet opening from the pump work chamber during the supply stroke, and wherein the piston is provided with a relief channel arrangement which connects the inlet opening to the constant pressure chamber. 17. An apparatus as defined in claim 16, wherein the pressure of the constant pressure chamber is equal to the inlet pressure. 18. An apparatus as defined in claim 11, wherein the apparatus also includes: an oblique control edge on the piston which acts as an axial limitation to the control face and which opens the diversion opening at the end of the supply stroke, a further valve which acts to close the diversion opening to prevent re-aspiration of a return-flow fuel quantity into the pump work chamber which is released at the end of the supply stroke; and wherein the magnetic valve is embodied as a multi-way valve which has an opening duration that determines a quantity of fuel to be injected into the engine and a quantity of fuel to replace the return-flow fuel quantity. 19. An apparatus as defined in claim 11, the pressure regulating valve having: a pressure regulating spring; an adjustment element which is connected to and corrected by the pressure regulating spring, wherein the apparatus includes a temperature sensing means which detects injection pump temperature and which is connected to the pressure regulating valve such that correction of the adjustment element by the pressure regulating spring is in accordance with injection pump temperature. 20. An apparatus as defined in claim 11, the pressure regulating valve having: a pressure regulating spring; an adjustment element which is connected to and corrected by the pressure regulating spring, wherein the apparatus includes a temperature sensing means which detects fuel temperature and which is connected to the pressure regulating valve such that correction of the adjustment element by the pressure regulating spring is in accordance with fuel temperature. 21. An apparatus as defined in claim 11, the pressure regulating valve having a chamber which contains a pressure regulating spring, the apparatus including: an auxiliary pump having a work chamber, which is driven parallel to the injection pump, and is supplied with fuel from the fuel supply; an intake line which connects the chamber of the pressure regulating valve with the auxiliary pump work chamber; wherein the intake line includes a check valve, which opens toward the work chamber, and wherein the auxiliary pump generates an underpressure which is substantially equal to a fuel vapor pressure occuring at an intake stroke of the injection pump and can be variably set to allow a partial filling of the auxiliary pump work chamber. 22. An apparatus as defined in claim 21, wherein the auxiliary pump is embodied as a piston pump. 23. An apparatus as defined in claim 11, the apparatus including: a means to generate a metering pulse to the magnetic inlet valve; a differentiation element which corrects the metering pulse to the magnetic inlet valve upon detecting a rapid shift in the instant of supply onset such that when the instant of supply onset shifts to a later time the fuel quantity is reduced, and such that when the instant of supply onset is towards an earlier time the fuel quantity is increased. 24. An apparatus as defined in claim 23, wherein the differentiation element generates a correction signal and is connected to the adjustment-path transducer, and wherein the electrical control device is connected to receive the correction signal from the differentiation element and an output from the adjustment-path transducer, which determine the correction of the metering pulse to the magnetic inlet valve in accordance with the correction signal and the adjustment-path transducer output. 25. An apparatus as defined in claim 23, also including an rpm transducer, which is connected to generate an output to the electrical control device, wherein the differentiation element is connected to generate a correction signal to the electrical control device to determine the correction of the metering pulse to the magnetic inlet valve in accordance with the correction signal and the rpm transducer output. 26. An apparatus as defined in claim 24, wherein the differentiation element is an electrical element and comprises an R-C circuit having at least one capacitor and two resistors. 27. An apparatus as defined in claim 25, wherein the differentiation element is an electrical element and comprises an R-C circuit having at least one capacitor and two resistors. 28. An apparatus as defined in claim 24, wherein the differentiation element is an electromechanical element which includes: an adjustment means, a potentiometer which is adjusted by the adjustment means; and at least one mechanical damping element connected to damp the movement of the potentiometer. 29. An apparatus as defined in claim 25, wherein the differentiation element is an electromechanical element which includes: an adjustment means; a potentiometer which is adjusted by the adjustment means; and at least one mechanical damping element connected to damp the movement of the potentiometer.