Abstract: A mechanical system has a component, which is movable under friction. An oscillating micromotion (dither) is impressed upon the component, which, if necessary, is added to a non-oscillating base motion of the component. It is provided that the micromotion (without the base motion that is additional, if necessary) is faster within a period of the oscillation in the one direction and is of shorter duration than in the opposite direction (asymmetrical dither).

Abstract: A mechanical system has a component, which is movable under friction. An oscillating micromotion (dither) is impressed upon the component, which, if necessary, is added to a non-oscillating base motion of the component. It is provided that the micromotion (without the base motion that is additional, if necessary) is faster within a period of the oscillation in the one direction and is of shorter duration than in the opposite direction (asymmetrical dither).

Abstract: A method for cooling a fuel injection system and fuel injection systems are proposed that improve the hot-starting performance of the internal combustion engine.

Abstract: An internal combustion engine is provided with an injection valve with which fuel can be injected directly into a combustion chamber either during a compression phase in a first operating mode or during an intake phase in a second operating mode. In addition, a control unit is provided for shifting between the two operating modes and for differentiated control and/or regulation of the performance quantities that influence the actual torque of the internal combustion engine as a function of a setpoint torque in both operating modes. A change in the actual torque during a shifting operation is determined by the control unit, and at least one of the performance quantities is influenced by the control unit as a function thereof.

Abstract: A method for cooling a fuel injection system and fuel injection systems are proposed that improve the hot-starting performance of the internal combustion engine.

Abstract: An internal combustion engine in for a motor vehicle in (1) is described. The internal combustion engine (1) has an injection valve with which fuel can be injected directly into a combustion chamber either during a compression phase in a first operating mode or during an intake phase in a second operating mode. In addition, a control unit is provided for shifting between the two operating modes and for differential control and/or regulation of the performance quantities that influence the actual moment of the internal combustion engine in both operating modes as a function of a setpoint moment. A change in the actual moment during a shifting operation is determined by the control unit and at least one of the performance quantities is influenced by the control unit as a function thereof.

Abstract: An internal combustion engine, in particular for a motor vehicle, is described. The internal combustion engine is equipped with an injection valve with which fuel can be injected directly into a combustion chamber either, in a first operating mode, during a compression phase or, in a second operating mode, during an intake phase. Also provided is a control device for switching between the two operating modes and for differing open-loop and/or closed-loop control, in the two operating modes, of the operating variables influencing the actual torque of the internal combustion engine as a function of a reference torque. A change in the actual torque during a switchover is operation is detected by the control device and as a function thereof, at least one of the operating variables is influenced by the control device.

Abstract: The device for determining load in internal combustion engines includes a pressure sensor connected with a combustion chamber of an internal combustion engine which produces an output signal depending on a combustion chamber pressure, a crankshaft angle sensor for detection of a crankshaft angle of the internal combustion engine and a processor for determining a load of the engine from relative values of the output signal of the pressure sensor at predetermined crankshaft angles. The processor includes a device for determining the load from a pressure difference between combustion chamber pressures measured at two different predetermined crankshaft angles (x1, x2) or from two integrated pressure values. The integrated relative pressure values are obtained by integration of a pressure-proportional output signal of the pressure sensor between two different predetermined crankshaft angles.

Abstract: An internal combustion engine especially for a motor vehicle is described which is provided with an injection valve (11) with which fuel from a tank (3) can be injected directly into a combustion chamber either in a first mode of operation (S) during a compression phase or in a second mode of operation (H) during an induction phase. Furthermore, the internal combustion engine is provided with a control apparatus (10) for controlling (open loop and/or closed loop) the engine. A line (13) is provided via which vaporized fuel from the tank (3) can be conducted into the combustion chamber in the second mode of operation (H).

Abstract: An internal combustion engine for motor vehicles, with an intake tube for aspirating combustion air, in which the tube leads to at least one combustion cylinder, and in which tube a throttle valve is disposed. The intake tube effects a mixing of combustion air and fuel vapor downstream of the throttle valve. For the sake of intensive mixing of fuel vapor and combustion air into a largely homogeneous mixture, the fuel vapor generated in a fuel evaporator outside the intake tube is introduced via a delivery device into air turbulence paths that unavoidably develop downstream of the throttle valve in the intake tube as a consequence of the geometry of the intake tube and/or throttle valve.

Abstract: A fuel injection for internal combustion engines, having a valve member which is guided so that it moves axially in a valve body and uses a sealing face provided on a combustion chamber end to open and close an injection opening on the valve body. A piezoelectric actuator includes a piezoelectric stack, which changes in length with the action of a control voltage, is coupled to the combustion chamber end of the valve member to actuate the valve member. In order to prevent an interference with a precise adjustment motion of the valve member of an unwanted length change in the piezoelectric stack, a clamping device is provided which fixes the end of the piezoelectric stack remote from the valve member in its axial position during the injection phase of the fuel injection valve, and permits an axial compensation for play at the piezoelectric stack during an injection pause.

Abstract: A metering valve for metering a fluid for a fuel injection valve for internal combustion engines, with a hydraulic displacement amplifier for converting the actuating displacement of a piezoelectric actuator into an increased stroke of the valve needle. Integrating the displacement amplifier spatially into the valve housing in an "O valve" to give a small overall volume is served by providing the lifting piston of the displacement amplifier with an end section of reduced diameter which projects into a recess in the operation piston of the displacement amplifier. A Belleville spring lying in the amplifier chamber bounded by the pistons presses the operating piston against the actuator, and a helical compression spring arranged in the recess concentrically to the end section presses the lifting piston against the valve needle.

Abstract: In a cylinder-selective injection system for an internal combustion engine, there are cylinder-selective injection suppressions. Subsequent to the suppressions, restoring added quantities specific to an individual cylinder are generated, whose initial value is dependent upon the number of suppressed injections for the cylinder in question, and whose notching-down to zero is dependent upon the number of injections of the cylinder that have taken place after completion of the suppression.

Abstract: The invention is directed to a method and an arrangement for controlling the supply of secondary air to the exhaust gas of an internal combustion engine. A method for diagnosing this arrangement is also provided. The arrangement includes an electrically operated secondary air pump which can be operated in at least two stages in dependence upon operating parameters of the engine. In this way, the supply of secondary air can be finely adapted to the actual value of the exhaust gas quantity supplied by the engine. This fine adaptation is determined by the number of stages. Resistors are switched into the current supply of the secondary air pump for the drive which has at least two stages.

Abstract: In order to determine the fuel quantity to be fed into an internal combustion engine during each stroke of the engine, the air mass sucked into each cylinder for combustion during each intake stroke is determined based on an intake-pipe pressure. A current air mass is determined using a measured value for the intake-pipe pressure. Subsequently, during a period in which there is no change in an air intake cross-section for each cylinder, the air mass is determined using a projected intake-pipe pressure, and the fuel quantity to be fed to each cylinder during the current and subsequent intake strokes is determined based on the air mass determinations and a wall film model.

Abstract: The emission of toxic materials when starting an internal combustion engine equipped with a catalytic converter and a secondary air pump can be further reduced with the method and arrangement of the invention. This reduction takes place by a switch-on of the secondary air pump under selectable conditions which include a warm start of the engine. The danger of overheating the catalytic converter by the operation of the secondary air pump for a warm engine is taken into account by a variable switch-on duration of the secondary air pump which can be realized by a counting procedure having an increment dependent on operating parameters.

Abstract: To measure the irregular running of an internal combustion engine, the following equation, for the running irregularity value (LUW) is applied:LUW=f(T)x.vertline.(T.sub.-- V2-T.sub.-- V1)-(T.sub.-- V3-T.sub.-- V2).vertline.,The values T.sub.-- V1, T.sub.-- V2 and T.sub.-- V3 are combustion time periods, as they are measured at any one time between two fixed segment marks. Different groups of runningirregularity values are formulated, which differ in that combustion time periods are applied in the mentioned equation for different combinations of cylinders. In each group, the running-irregularity values are averaged; and the difference between the minimum and the maximum value of the averaged values is formulated. The difference is evaluated as a variable for the extent of running irregularity.

Abstract: In a method for protecting a catalytic converter from overheating, a conventional misfire recognition method is used to determine whether misfires are occurring in a cylinder. If this is the case, an attempt is made to interrupt the fuel supply to the affected cylinder. If this succeeds, the remaining cylinders are supplied with a lean mixture. If it does not succeed, all the cylinders are operated with a rich mixture. The lean setting of the mixture in the case of interrupted fuel supply to the affected cylinder has the effect that after the combustions in the cylinders, no further fuel reaches the catalytic converter which could combust in the catalytic converter with the oxygen induced by the affected cylinder.

Abstract: The invention is directed to a method for determining misfires in an internal combustion engine of a motor vehicle. The determination is discontinued after a misfire under specific further conditions for a pregiven number of ignition strokes. When the misfire determination is not discontinued, then a check is made as to whether simple measurement value relationships apply which make a misfire very improbable. If such measurement value relationships are present, then the actual complicated misfire determination is discontinued. It is of special significance to count ignition strokes, which are counted in order to determine the relative frequency of misfires, only then when the above-mentioned conditions are all satisfied which determine as to whether a condition is present at all in which a determination of the misfire is purposeful. In this way, the decisive frequency determination is not influenced by the count of the ignition strokes which are not at all relevant to misfires.

Abstract: To detect knock, a detected signal relating to a combustion property in a cylinder of an engine is generated. The detected signal (I) is filtered to select those portions characteristic of knock. However, the filtered signal (I') is only investigated to determine whether knock has occurred, when the unfiltered detected signal (I) meets at least two, and usually four, preset conditions. One preset condition is that the detected signal (I) must have reached a predetermined threshold value (I.sub.s). Other preset conditions for the detected signal include the following: that the maximum value (I.sub.max) of the detected signal (I) is below a predetermined critical value (I.sub.max crit) and that within a predetermined crank angle difference (.DELTA..alpha..sub.F), after reaching the threshold value (I.sub.s), during a predetermined time interval (.DELTA.t) the detected signal (I) does not decrease by more than a first critical amount (.DELTA.I.sub.