Abstract: The present invention relates to a method for operating a fuel supply system for an internal combustion engine, and to a corresponding device. The fuel supply system of an internal combustion engine may include: an outlet of a high-pressure pump coupled to a pressure-limiting valve and a high-pressure fluid accumulator. The method may include, when the internal combustion engine is set into a deactivated state, actuating the high-pressure pump such that, at the outlet side of the high-pressure pump, a pressure is increased such that the pressure-limiting valve is opened.

Abstract: The present disclosure relates to internal combustion engines and the teachings thereof may be embodied in methods and apparatus for detecting a malfunctioning rail pressure sensor. Some embodiments may include a method for detecting a malfunctioning rail pressure sensor comprising: delivering an analog output signal characterizing the rail pressure to a control unit; generating a differential rail pressure signal as a digital output signal; delivering the differential rail pressure signal of the rail pressure sensor to the control unit; analyzing the analog output signal and the differential rail pressure signal in the control unit; and detecting a malfunctioning rail pressure sensor based on the analysis by the control unit.

Abstract: A method for operating a fuel injection system of an internal combustion engine is disclosed. The fuel injection system comprises a high pressure accumulator (rail) and a high-pressure fuel pump with a digital inlet valve and which guides fuel into the high pressure accumulator. The number of the control pulses for the digital inlet valve and thus the number of the pump delivery strokes is reduced with respect to the number of the injection steps of an injector of the injection system, in order to thereby reduce the noise and the energy consumption of the high-pressure pump.

Abstract: The present disclosure relates to internal combustion engines and the teachings thereof may be embodied in methods and apparatus for detecting a malfunctioning rail pressure sensor. Some embodiments may include a method for detecting a malfunctioning rail pressure sensor comprising: delivering an analog output signal characterizing the rail pressure to a control unit; generating a differential rail pressure signal as a digital output signal; delivering the differential rail pressure signal of the rail pressure sensor to the control unit; analyzing the analog output signal and the differential rail pressure signal in the control unit; and detecting a malfunctioning rail pressure sensor based on the analysis by the control unit.

Abstract: The present invention relates to a method for operating a fuel supply system for an internal combustion engine, and to a corresponding device. The fuel supply system of an internal combustion engine may include: an outlet of a high-pressure pump coupled to a pressure-limiting valve and a high-pressure fluid accumulator. The method may include, when the internal combustion engine is set into a deactivated state, actuating the high-pressure pump such that, at the outlet side of the high-pressure pump, a pressure is increased such that the pressure-limiting valve is opened.

Abstract: A method for determining an error in a pressure, which is measured by means of a pressure sensor in a pressure accumulator for accumulating fuel that can be let out of the pressure accumulator via an injection valve and injected into a cylinder, wherein the method comprises: determining at least two 3-tuples of a first pressure, a period of time, and a second pressure, wherein each first pressure is measured by the pressure sensor; wherein after measuring each first pressure, the valve is opened for a period of time; and wherein after the opening of the valve for the period of time, the second pressure is measured by the pressure sensor; and determining the error of the measured pressure from the at least two 3-tuples.

Abstract: A method is disclosed for operating a high-pressure accumulator fuel injection system for an internal combustion engine of a motor vehicle which has a stop-start automatic function by way of which the internal combustion engine can be switched off and restarted afterwards independent of the intervention of the driver of the motor vehicle, the fuel being conveyed to the high-pressure accumulator as needed by means of a high-pressure pump and the pressure of the fuel being adjusted on the pressure side by means of a pressure control valve which is electrically actuated and open when de-energized. According to the method, the supply with power of the pressure control valve is adapted to the prevailing pressure in the high-pressure accumulator during a stop phase within a stop-start cycle.

Abstract: A valve includes a spring having a spring force, an actuator having an actuator force that acts against the spring force, and a tappet that can be actuated by means of the actuator. The valve also includes a sealing element, which is or can be coupled to the tappet, and a sealing seat, such that the valve is closed when the sealing element lies against the sealing seat. A current having a specified curve, proceeding from an initial value of the current to a specified final value of the current, is applied during a specified time interval of the actuator after a closing phase of the valve for a normally open valve or after an opening phase for a normally closed valve. The initial value of the current is less than the final value.

Abstract: A method for operating a fuel injection system of an internal combustion engine is disclosed. The fuel injection system comprises a high pressure accumulator (rail) and a high-pressure fuel pump with a digital inlet valve and which guides fuel into the high pressure accumulator. The number of the control pulses for the digital inlet valve and thus the number of the pump delivery strokes is reduced with respect to the number of the injection steps of an injector of the injection system, in order to thereby reduce the noise and the energy consumption of the high-pressure pump.

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

Abstract: A method for analyzing the efficiency of a high-pressure pump of a fuel injection system includes analyzing the efficiency of the high-pressure pump with respect to individual pumping strokes of the high-pressure pump, detecting and analyzing the pressure build-up and the pressure drop for the individual pumping strokes, and drawing conclusions about the state of individual components of the high-pressure pump from the analysis of the pressure build-up or the pressure drop.

Abstract: A fuel injection system of an internal combustion engine includes a first and a second fuel pump, a leakage-prone volume flow regulating valve arranged in a fuel line between the first and the second fuel pump, and a control unit configured to actuate the first fuel pump as a function of a position of the leakage-prone volume flow regulating valve, such that the leakage-prone volume flow regulating valve serves as the sole actuating element for pressure regulation in the fuel injection system. An associated pressure regulating method is also disclosed.

Abstract: A method is provided for controlling a valve having a spring, a pin, and an actuator for actuating the pin. A current having a specified current profile is applied to the actuator, starting from an initial current value at which the pin is in an initial position in which the pin allows the valve to move between open and closed positions. The current profile includes a section or several consecutive sections, wherein each section defines an initial current value and a final current value, a first time interval having a continuously falling current, and a subsequent second time interval having a continuously rising current. For each section, the final current value is less than the initial current value. After the specified current profile has been passed through, the pin is in a final position in which the pin prevents the valve from moving between open and closed positions.

Abstract: A method is provided for operating an injection system of a motor vehicle, which injection system is designed as an adjusting system having volumetric flow rate control via a normally open inlet valve. If a fault of the inlet valve leading to undesired closing of the inlet valve is detected, the inlet valve is closed already during the suction phase of the high-pressure pump by applying current and is opened again during a part of the suction phase corresponding to a pumping demand in order to thereby control or at least reduce the flow rate of the high-pressure pump. Thus, corresponding safety measures, such as a pressure-limiting valve in the high-pressure region, can be omitted.

Abstract: A method is provided for operating an injection system of a motor vehicle, which injection system is designed as an adjusting system having volumetric flow rate control via a normally open inlet valve. If a fault of the inlet valve leading to undesired closing of the inlet valve is detected, the inlet valve is closed already during the suction phase of the high-pressure pump by applying current and is opened again during a part of the suction phase corresponding to a pumping demand in order to thereby control or at least reduce the flow rate of the high-pressure pump. Thus, corresponding safety measures, such as a pressure-limiting valve in the high-pressure region, can be omitted.

Abstract: A method for analyzing the efficiency of a high-pressure pump of a fuel injection system includes analyzing the efficiency of the high-pressure pump with respect to individual pumping strokes of the high-pressure pump, detecting and analyzing the pressure build-up and the pressure drop for the individual pumping strokes, and drawing conclusions about the state of individual components of the high-pressure pump from the analysis of the pressure build-up or the pressure drop.

Abstract: A valve includes a spring having a spring force, an actuator having an actuator force that acts against the spring force, and a tappet that can be actuated by means of the actuator. The valve also includes a sealing element, which is or can be coupled to the tappet, and a sealing seat, such that the valve is closed when the sealing element lies against the sealing seat. A current having a specified curve, proceeding from an initial value of the current to a specified final value of the current, is applied during a specified time interval of the actuator after a closing phase of the valve for a normally open valve or after an opening phase for a normally closed valve. The initial value of the current is less than the final value.

Abstract: A method is provided for controlling a valve having a spring, a pin, and an actuator for actuating the pin. A current having a specified current profile is applied to the actuator, starting from an initial current value at which the pin is in an initial position in which the pin allows the valve to move between open and closed positions. The current profile includes a section or several consecutive sections, wherein each section defines an initial current value and a final current value, a first time interval having a continuously falling current, and a subsequent second time interval having a continuously rising current. For each section, the final current value is less than the initial current value. After the specified current profile has been passed through, the pin is in a final position in which the pin prevents the valve from moving between open and closed positions.

Abstract: A fuel injection system of an internal combustion engine includes a first and a second fuel pump, a leakage-prone volume flow regulating valve arranged in a fuel line between the first and the second fuel pump, and a control unit configured to actuate the first fuel pump as a function of a position of the leakage-prone volume flow regulating valve, such that the leakage-prone volume flow regulating valve serves as the sole actuating element for pressure regulation in the fuel injection system. An associated pressure regulating method is also disclosed.

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