Abstract: Disclosed is a method and a device for predicting the failure time of the pressure limiting valve of a high-pressure fuel pump of a motor vehicle. The method includes measuring a characteristic parameter of the pressure limiting valve each time the motor vehicle has been switched off, determining and storing a variable determined by using the measured characteristic parameter, determining the time profile of the variable determined from the characteristic parameter, predicting the future profile of the variable determined from the characteristic parameter, and comparing the predicted future profile of the variable determined from the characteristic parameter with a predetermined wear limiting value. The comparison is to predict the time at which the predicted future profile of the variable determined from the characteristic parameter reaches the predetermined wear limiting value.

Abstract: The disclosure relates to a method for pressure regulation in a fuel high-pressure injection system having an overpressure valve, in which pressure pulsations occur which are caused by fuel being pumped into a high-pressure fuel accumulator and extracted from the high-pressure fuel accumulator. The method includes detecting pressure values of the fuel present in the high-pressure fuel accumulator. The method also includes comparing the detected pressure values with a nominal pressure value; and carrying out a pressure regulation in which the fuel pressure prevailing in the high-pressure fuel accumulator is set to the nominal pressure value. During pressure regulation, a peak pressure value of the detected pressure values is used as the actual pressure value. The disclosure also relates to a device for pressure regulation in a fuel high-pressure injection system.

Abstract: A method for operating an internal combustion engine with detection of the fuel used for injection is described. In the method, the elasticity modulus of the fuel to be injected is determined at a first and a second injection pressure. A difference value is calculated from the difference between the two elasticity modulus values related to the pressure difference and is compared with a differentiating value. The fuel being used is detected depending on whether the difference value is above or below the differentiation value. In particular, the method is used for differentiating diesel fuel EN590 and biodiesel.

Abstract: Disclosed is a method and a device for predicting the failure time of the pressure limiting valve of a high-pressure fuel pump of a motor vehicle. The method includes measuring a characteristic parameter of the pressure limiting valve each time the motor vehicle has been switched off, determining and storing a variable determined by using the measured characteristic parameter, determining the time profile of the variable determined from the characteristic parameter, predicting the future profile of the variable determined from the characteristic parameter, and comparing the predicted future profile of the variable determined from the characteristic parameter with a predetermined wear limiting value. The comparison is to predict the time at which the predicted future profile of the variable determined from the characteristic parameter reaches the predetermined wear limiting value.

Abstract: A method for operating an internal combustion engine with detection of the fuel used for injection is described. In the method, the elasticity modulus of the fuel to be injected is determined at a first and a second injection pressure. A difference value is calculated from the difference between the two elasticity modulus values related to the pressure difference and is compared with a differentiating value. The fuel being used is detected depending on whether the difference value is above or below the differentiation value. In particular, the method is used for differentiating diesel fuel EN590 and biodiesel.

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 pressure-limiting valve for a fuel injection system includes a housing having a fluid inlet and a fluid outlet, a sealing seat, and a sealing body configured to move between a closed position in which the sealing body is in contact with the sealing seat, which blocks fluid flow from the fluid inlet to the fluid outlet, and additional positions that permit such fluid flow, and a holding device for keeping the sealing body in one of the additional positions if the sealing body is moved at least a specified distance away from the sealing seat.

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 includes applying a specified starting voltage to a valve actuator in a first specified operating mode for closing the valve, the valve having a spring with a spring force against which an actuator force of the actuator acts. In the first operating mode, a first period of time is ascertained which represents that a maximum current value has been reached. Furthermore, a second period of time is ascertained which represents that a minimum current value has been reached. In a specified second operating mode, the specified starting voltage is applied to the actuator until the end of the first period of time is reached, and a control voltage is then applied to the actuator until the end of the second period of time is reached, wherein the average value of the control voltage is lower than the average value of the starting voltage.

Abstract: A method for operating a high-pressure pump of an injection system and an injection system is provided. The method relates to a switching off of additional pulses, which are applied to a valve of the high-pressure pump, if the determined coil temperature of the valve exceeds a limit value. The method is, for instance, then carried out if additional pulses are applied to the valve to reduce noise (“whisper function”). Current information and voltage information from the control signal of the valve of the high-pressure pump are used to measure the temperature of the valve and switch off additional current pulses through this information if there is a risk of the valve overheating. The disclosure further describes an injection system of a combustion engine, wherein the injection system comprises a high-pressure pump having a valve and a corresponding control unit.

Abstract: An internal combustion engine has a pressure accumulator, a high-pressure pump, a controllable actuator, and camshaft. The high-pressure pump includes a pump piston movably arranged in a cylinder chamber. The pump piston is supported on the camshaft and thus influences an open volume of the cylinder chamber depending on a rotation of the camshaft. The cylinder chamber is hydraulically coupled to the pressure accumulator to pump the fluid into the pressure accumulator. The actuator drives the camshaft such that the camshaft rotates about the camshaft's longitudinal axis in a specified angular range. The high-pressure pump is controlled prior to an expected motor start such that the high-pressure pump is in a self-priming operating state and the actuator is controlled such that the camshaft rotates about the camshaft longitudinal axis in the specified angular range at least once in a first direction and at least once in an opposite second direction.

Abstract: A method is disclosed for controlling a valve having a spring with a spring force, an actuator with an actuator force opposing the spring force, and a pin that is actuated by the actuator, a seal element that can be coupled with the pin, and a seal seat, the valve being closed when the seal element sits against the seal seat. The method includes determining an expected natural opening time when the seal element is lifted off the seal seat based on a pressure difference in front and behind the valve, impressing a specified current on the actuator at a point in time within a specified interval prior to the natural opening time, the seal element sitting against the seal seat at the point in time such that the pin contacts the seal element and the actuator force matches the spring force, which is reduced by a specified value.

Abstract: A pressure-limiting valve for a fuel injection system includes a housing having a fluid inlet and a fluid outlet, a sealing seat, and a sealing body configured to move between a closed position in which the sealing body is in contact with the sealing seat, which blocks fluid flow from the fluid inlet to the fluid outlet, and additional positions that permit such fluid flow, and a holding device for keeping the sealing body in one of the additional positions if the sealing body is moved at least a specified distance away from the sealing seat.

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: An electrically controllable electromechanical inlet valve (2a) which is closed in the currentless state and is held in the closed state by the force of a spring (2b), an outlet valve (5a), and a displacement element (6), the inlet valve is operated in a self-controlling operating mode after a start command is present. In the self-controlling operating mode, the rail pressure is built without knowledge of the phase position of the displacement element. During the self-controlling operating mode, the phase position of the displacement element is determined. After the phase position of the piston or displacement element is determined, the inlet valve is switched over to a non-self-controlling operating mode.

Abstract: A method includes applying a specified starting voltage to a valve actuator in a first specified operating mode for closing the valve, the valve having a spring with a spring force against which an actuator force of the actuator acts. In the first operating mode, a first period of time is ascertained which represents that a maximum current value has been reached. Furthermore, a second period of time is ascertained which represents that a minimum current value has been reached. In a specified second operating mode, the specified starting voltage is applied to the actuator until the end of the first period of time is reached, and a control voltage is then applied to the actuator until the end of the second period of time is reached, wherein the average value of the control voltage is lower than the average value of the starting voltage.

Abstract: An internal combustion engine has a pressure accumulator, a high-pressure pump, a controllable actuator, and camshaft. The high-pressure pump includes a pump piston movably arranged in a cylinder chamber. The pump piston is supported on the camshaft and thus influences an open volume of the cylinder chamber depending on a rotation of the camshaft. The cylinder chamber is hydraulically coupled to the pressure accumulator to pump the fluid into the pressure accumulator. The actuator drives the camshaft such that the camshaft rotates about the camshaft's longitudinal axis in a specified angular range. The high-pressure pump is controlled prior to an expected motor start such that the high-pressure pump is in a self-priming operating state and the actuator is controlled such that the camshaft rotates about the camshaft longitudinal axis in the specified angular range at least once in a first direction and at least once in an opposite second direction.

Abstract: A method for controlling a valve including a spring, an actuator having an actuator force opposing the spring, and a pin actuatable by the actuator. To open the valve, in a first operating mode a current having a predefined curve is applied to the actuator, starting from a starting value of the current at which the pin is positioned to allow the valve to close, measured values of the current are determined chronologically sequentially, a reference value of the current takes on the current measured value of the current when the measured current deviates from the applied current by a predefined degree. In a second operating mode, a current having a predefined curve is applied to the actuator, starting with the starting value of the current to a final value of the current at which the pin is in a position that prevents the valve from closing.

Abstract: A method is disclosed for controlling a valve having a spring with a spring force, an actuator with an actuator force opposing the spring force, and a pin that is actuated by the actuator, a seal element that can be coupled with the pin, and a seal seat, the valve being closed when the seal element sits against the seal seat. The method includes determining an expected natural opening time when the seal element is lifted off the seal seat based on a pressure difference in front and behind the valve, impressing a specified current on the actuator at a point in time within a specified interval prior to the natural opening time, the seal element sitting against the seal seat at the point in time such that the pin contacts the seal element and the actuator force matches the spring force, which is reduced by a specified value.

Abstract: In a method for adapting the performance of a fuel prefeed pump of a motor vehicle which has a common rail injection system and an internal combustion engine, after the ignition is switched on and before the internal combustion engine is started, adaptation values are determined and stored which are assigned to the fuel prefeed pump and describe its individual performance. After the internal combustion engine is started, the stored adaptation values are taken into consideration during the determining of an actuating signal for the prefeed pump.