Abstract: A fuel pressure regulating system for an internal combustion engine has a pressure accumulator which is used to store fuel under pressure and to feed the combustion chambers of the internal combustion engine by fuel-supplying injectors, a high-pressure pump which supplies a fuel mass flux to the pressure accumulator, a first valve via which the fuel can be guided out of the pressure accumulator, and a second valve for restricting the fuel mass flux. The system is provided with a first control loop having the first valve as an actuator for regulating the pressure in the pressure accumulator, and a second control loop having the second valve as an actuator for regulating the pressure in the pressure accumulator, and the two control loops are embodied as cascade regulators, the first control loop being a master regulator and the second control loop being a follower regulator.

Abstract: An injection system for injecting fuel has an actuator, a pilot valve with a valve mushroom, and a supply throttle. The control chamber encompasses a control piston, a first discharge throttle, a first sealing edge for forming a first sealing seat along with the valve mushroom, a second sealing edge of a piston chamber with a valve piston, the second sealing edge forming a second sealing seat along with the valve piston during a maximum actuator working lift for sealing the piston chamber and the valve chamber from each other; and a second discharge throttle connecting the piston chamber to the low-pressure zone between the first and the second sealing edge, wherein d1>d2>d3, d1 are the minimum diameter of the first discharge throttle, d2 being the minimum diameter of the second discharge throttle, and d3 being the minimum diameter of the supply throttle.

Abstract: A method for operating an internal combustion engine has the steps: (a) during an overrun phase of the internal combustion engine, activating an injector of a first combustion chamber for a predetermined activation time ?inj with a predetermined activation voltage Ui=1, (b) measuring a torque variation, (c) determining, from the torque variation, a fuel quantity mi=1 of the fuel injected by the injector during the activation time ?inj, (d) varying the activation voltage to a value Ui+1 which differs from Ui, (e) repeating steps (a) to (d) with further incrementation of i until i has reached a preset value N or the internal combustion engine is no longer in the overrun phase, and (f) determining an injector characteristic value of the injector of the first combustion chamber from the fuel quantities m1, m2, . . . , mN and the activation voltages U1, U2, . . . , UN.

Abstract: In a method for pressure control in an injection system of an internal combustion engine, a pump efficiency dependent upon the type of pump is taken into account in the control of a high-pressure stored value. To this end, the pump efficiency may be determined based on a stored table or a proximity function.

Abstract: In a method and a device for determining an operating characteristic of an injection system, to determine an operating characteristic (30) of an internal combustion engine (1) that is charged by a turbocharger (4), the method has the following steps: A) carrying out a pilot injection of fuel into a cylinder (51, 52, 53, 54) of the internal combustion engine using the injection system (30); B) determining an operating parameter of the turbocharger (40); C) determining an operating characteristic of the injection system (30) using the operating parameter of the turbocharger (40) previously determined.

Abstract: In a method for determining an uncontrolled acceleration of an internal combustion engine, a valve opening cross section is allocated to each load state of the internal combustion engine. In the event that a controller value is outside a limit range, an uncontrolled acceleration of the internal combustion engine is thereby detected.

Abstract: In a method of operating an internal combustion engine having at least two combustion chambers, each combustion chamber contributes torque to the total torque of the internal combustion engine, and the internal combustion engine is designed in such a way that a quantity of exhaust gas can be recycled into combustion chambers. The method has the steps: (a) detecting the torque contributions of at least two combustion chambers, then (b) changing the quantity of exhaust gas recycled into the combustion chambers, the torque contribution of which has been detected in step (a), then (c) detecting the torque contributions of at least two combustion chambers, the torque contribution of which has been detected in step (a), then (d) determining the change in the torque contributions as a result of the change in the quantity of recycled exhaust gas, and then (e) outputting a signal as a function of the change in the torque contributions.

Abstract: A common rail injection system for an internal combustion engine has at least one combustion chamber, a high pressure fuel pump for supplying fuel, a high pressure fuel accumulator connected to the high pressure fuel pump for storing fuel pinj at injection pressure in relation to the environment of the common rail injection system, an injector connected to the high pressure fuel accumulator for delivering fuel into the at least one combustion chamber, and a return line for returning fuel from the injector to the high pressure fuel pump. The fuel is pressurized by a return line pressure pdrain in relation to the environment of the common rail injection system. It is proposed that the common rail injection system has an adjusting means for adjusting the return line pressure pdrain. It is additionally proposed to use a pressure control means in the fuel leakage flow feedback system of an internal combustion engine.

Abstract: In a method and an apparatus which more accurately reach a predefined setpoint value of a combustion characteristic variable for an internal combustion engine (1) with an injection system (30), a first injection signal which triggers an injection of fuel into a combustion chamber (53) of the internal combustion engine (1) is generated using at least one injection signal parameter. A combustion signal which represents a combustion of the injected fuel is generated by a detector (40). The combustion characteristic variable is determined using the combustion signal. The injection signal parameter is corrected using a deviation of the combustion characteristic variable from a setpoint value, in such a way that the deviation of a second injection signal which is generated using the corrected injection parameter is reduced for an injection which is to be performed later.

Abstract: A method for operating an internal combustion engine has the steps: (a) during an overrun phase of the internal combustion engine, activating an injector of a first combustion chamber for a predetermined activation time ?inj with a predetermined activation voltage Ui±1, (b) measuring a torque variation, (c) determining, from the torque variation, a fuel quantity mi=1 of the fuel injected by the injector during the activation time ?inj, (d) varying the activation voltage to a value Ui+1 which differs from Ui, (e) repeating steps (a) to (d) with further incrementation of i until i has reached a preset value N or the internal combustion engine is no longer in the overrun phase, and (f) determining an injector characteristic value of the injector of the first combustion chamber from the fuel quantities m1, m2, . . . , mN and the activation voltages U1, U2, . . . , UN.

Abstract: In a method and device for characterising the return stroke of injectors, in particular piezo-injectors of an internal combustion engine provided with a common rail system, when the internal combustion engine is switched off, a constant pressure is dropped in the rail, thereby making it possible to measure the rail pressure and to adjust the injectors by corresponding power. The actuating power is increased until a discontinuity in a temporal progression of rail pressure occurs. The actuating energy applied for the state and a pressure available in the make it possible to measure the return stroke of corresponding injector.

Abstract: A common rail injection system for an internal combustion engine has at least one combustion chamber, a high pressure fuel pump for supplying fuel, a high pressure fuel accumulator connected to the high pressure fuel pump for storing fuel pinj at injection pressure in relation to the environment of the common rail injection system, an injector connected to the high pressure fuel accumulator for delivering fuel into the at least one combustion chamber, and a return line for returning fuel from the injector to the high pressure fuel pump. The fuel is pressurized by a return line pressure pdrain in relation to the environment of the common rail injection system. It is proposed that the common rail injection system has an adjusting means for adjusting the return line pressure pdrain. It is additionally proposed to use a pressure control means in the fuel leakage flow feedback system of an internal combustion engine.

Abstract: In a method and device for characterising the return stroke of injectors, in particular piezo-injectors of an internal combustion engine provided with a common rail system, when the internal combustion engine is switched off, a constant pressure is dropped in the rail, thereby making it possible to measure the rail pressure and to adjust the injectors by corresponding power. The actuating power is increased until a discontinuity in a temporal progression of rail pressure occurs. The actuating energy applied for said state and a pressure available in the make it possible to measure the return stroke of corresponding injector.

Abstract: A method and device control a volumetric flow in a common rail injection system of an internal combustion engine by producing a rail pressure with a high pressure pump, setting the rail pressure with a high pressure control valve and determining the volumetric flow by a valve position of a volumetric flow control valve controlled by a precontrol characteristic field and a two-dimensional adaptation characteristic field having adaptation values for the valve position predefined as a function of two operating parameters of the engine. This overcomes the problem in current common rail injection systems of the adapted valve position of the volumetric flow control valve often being subject to error, for instance because the valve position is controlled as a function of the rail pressure only using a one-dimensional adaptation characteristic field. This can lead to unwanted ambiguities, which can result in injecting fuel in incorrect quantities.

Abstract: A method and device control a volumetric flow in a common rail injection system of an internal combustion engine by producing a rail pressure with a high pressure pump, setting the rail pressure with a high pressure control valve and determining the volumetric flow by a valve position of a volumetric flow control valve controlled by a precontrol characteristic field and a two-dimensional adaptation characteristic field having adaptation values for the valve position predefined as a function of two operating parameters of the engine. This overcomes the problem in current common rail injection systems of the adapted valve position of the volumetric flow control valve often being subject to error, for instance because the valve position is controlled as a function of the rail pressure only using a one-dimensional adaptation characteristic field. This can lead to unwanted ambiguities, which can result in injecting fuel in incorrect quantities.

Abstract: The invention relates to the return stroke between an actuator and an element. In order to displace the element the actuator (A) is impinged upon by a control voltage (ANS). The control voltage (ANS) is selected in such a manner that it is dependent on the size of return stroke in order to compensate the alteration in the return stroke.

Abstract: The invention relates to the return stroke between an actuator and an element. In order to displace the element the actuator (A) is impinged upon by a control voltage (ANS). The control voltage (ANS) is selected in such a manner that it is dependent on the size of return stroke in order to compensate the alteration in the return stroke.