Abstract: A method for controlling knocking in multi-cylinder internal combustion engines in KC emergency operation and at activated guide-cylinder function are provided by which a torque loss is able to be avoided at low application expenditure and the functionality desired by the guide-cylinder function is maintained even in KC emergency operation. In KC emergency operation and when the guide-cylinder function is activated, cylinder pairs are formed from the cylinders operating in each case at a 360° offset. Each twin pair having at least one cylinder to be guided is assigned at least one of the available guide cylinders, so that the ignition timing retard of the cylinder pair to be guided is based on the ignition timing retard of the associated guide cylinder. Only when the number of available guide cylinders is insufficient will a safety retard timing be triggered, in which an ignition angle is adjusted which has been predefined for all cylinders.

Abstract: Devices and methods for knock detection and knock control are described, in which, in addition to the customary component parts, the knock-detection circuit has a filter with switchable filter characteristic. The switchover of the filter characteristic, i.e. the shift, for example, of the mid-frequency of the filter, is carried out taking into consideration specifiable quantities or parameters, for instance, as a function of rotational speed. During the switchover of the filter characteristic, i.e. the shift of the mid-frequency, problems could occur in the knock detection; that is why measures are proposed which carry out the knock detection according to a special knock-detection algorithm during a switchover phase lasting a specifiable time.

Abstract: A device having a monitoring circuit for a knock control and a control circuit (10) which initiates substitute measures in the event of a fault in the knock control, depending on the output signal (f) of the monitoring circuit, is described. The control unit is designed, for example, so that the number of fuel injection operations per operating cycle of a cylinder of the engine is increased as the substitute measure.

Abstract: A method and a device for controlling knock in response to the failure of a phase detector are described, which implement the normal, cylinder-selective knock control under the condition, that the dual ignition is not activated. If the dual ignition is activated when the phase detector fails, then the knock control is carried out, using a non-cylinder-selective measure. Such a non-cylinder-selective measure could include safety-ignition retard or knock control, using one knock-detection threshold value for all of the cylinders.

Abstract: The invention relates to a method for knock control of an internal combustion engine, a knock detection being carried out on the cylinders of the internal combustion engine and a moment of ignition being retarded by a specifiable value as a function of detected knocking combustion in at least one of the cylinders, the system including at least two evaluation electronics and at least one cylinder being assigned to each of these evaluation electronics, and the knock sensor signals assigned to the cylinders being evaluated by the evaluation electronics assigned in each case, and the knock detection and the specification of the moment of ignition being effected by a control electronics, and the evaluation electronics being monitored for functionality.

Abstract: A method for operating an internal combustion engine and a corresponding device are described in which a combustion of a fuel in a fuel-air mixture introduced into a cylinder occurs in at least one cylinder. At least one adjusting device is used to influence at least one physical process, which modifies the distribution of the constituents and/or the overall composition of the fuel-air mixture in the at least one cylinder. If knock occurs, a knock control is used to gradually retard an ignition angle in the at least one cylinder from a fundamental ignition angle by an adjustment angle. When the adjustment of the at least one adjusting device exceeds a specifiable first threshold and/or the change in the at least one physical process exceeds a specifiable second threshold, the adjustment angle is rapidly reduced by increments, the more rapid reduction occurring with a larger increment and/or with a higher frequency of increments.

Abstract: A method for knock detection in an internal combustion engine is disclosed, in which the output signal of at least one knock sensor, which is associated with the engine, is evaluated with the aid of an evaluation device. Knocking is detected when the prepared signal of the knock sensor exceeds a predeterminable reference level. The calculation of the input signal of the reference level tracking takes place as a function of whether the internal combustion engine is in a dynamic operating state or not, wherein in order to calculate the reference level in the event of dynamics, measurement values are also used which were determined when knocking was detected.

Abstract: A device for signal evaluation is described, in particular for knock recognition in an internal combustion engine, in which the signals forwarded by sensors are evaluated digitally and error recognition is carried out that performs two different test functions, whereby a first test function supplies a test pulse at a specifiable location, and the second test function clears the sensor signals, and the reaction of both the analog and digital parts of the circuit are monitored.

Abstract: A method for knock control during KC emergency operation with which, given low application expenditure, a torque gain can be attained, while the application reliability increases. The method for knock control of multi-cylinder internal combustion engines having 2n cylinders, a cylinder counter, at least one knock sensor and an evaluation unit for evaluating the knock-sensor signal with the aid of an individual knock-recognition characteristic for each cylinder, is characterized in that during KC emergency operation, cylinder pairs are formed from the cylinders operating offset in each case by 360°, and the minimal value of the two knock-recognition characteristics of the cylinder pair is assumed in each case as the knock-recognition threshold for the cylinders of the cylinder pair affected by the malfunction of the phase recognition.

Abstract: The apparatus detects knock in an internal combustion engine with at least one knock sensor associated with a cylinder of the internal combustion engine. The apparatus initially processes the analog knock sensor output signals in an analog signal preparing device (18), which can include a multiplexer and analog/digital converter, but the actual knock detection occurs only in a purely digital signal analysis device (19), which processes the prepared and digitized knock sensor output signals. The digital signal analysis device (19) extracts at least one knock index and compares it with predetermined threshold values for knock detection, preferably considering a reference value for knock-free operation. A method of detecting knock is also described which is based on the use of this apparatus.

Abstract: A device for suppressing engine knocks in an internal combustion engine, using a detection device for the detection of the respective operating parameters of the internal combustion engine; a control unit for determining manipulated variables for the injection and ignition on the basis of the acquired operating parameters; a dynamic phase detection device for acquiring a dynamic phase of the internal combustion engine; and a correction device for correcting the manipulated variables for the ignition, which is constructed so that for knock suppression, the ignition control quantity, given a dynamic phase acquired by the dynamic phase detection device, can be adjusted in the late direction by a dynamic lead that is dependent on a predicted load difference, and at the end of the dynamic phase can be brought step-by-step back to the manipulated variable determined by the control unit.

Abstract: A method and a device for fault detection or diagnosis are described which are used on a multi-cylinder internal combustion engine with a knock sensor. For diagnostic purposes an instantaneous reference value formed from the sensor signal is compared with predefinable upper or lower reference threshold levels. If the instantaneous reference value exceeds or falls below the thresholds to a predefinable extent, a malfunction is detected. The reference levels correspond, for example, to the background noise present in knock-free operation. The fault detection or diagnosis is performed only for the cylinder which emits the loudest noise or from which the loudest noise is recorded.

Abstract: A method for ignition control is described in which the load gradient is determined. The load gradient is compared with a first specifiable dynamic threshold and the ignition control variable is additively retarded by application of an adaptable dynamic derivative action if the load gradient exceeds the first dynamic threshold. If the load gradient exceeds a second specifiable dynamic threshold and no knock occurs, then the output dynamic derivative action is reduced so that the ignition is advanced again.

Abstract: A method for knock control during KC emergency operation with which, given low application expenditure, a torque gain can be attained, while the application reliability increases. The method for knock control of multi-cylinder internal combustion engines having 2n cylinders, a cylinder counter, at least one knock sensor and an evaluation unit for evaluating the knock-sensor signal with the aid of an individual knock-recognition characteristic for each cylinder, is characterized in that during KC emergency operation, cylinder pairs are formed from the cylinders operating offset in each case by 360°, and the minimal value of the two knock-recognition characteristics of the cylinder pair is assumed in each case as the knock-recognition threshold for the cylinders of the cylinder pair affected by the malfunction of the phase recognition.

Abstract: The method for knock detection includes establishing that knock is occurring in the internal combustion engine when the amplified knock signal exceeds a predetermined reference level in a predetermined manner. The reference level is determined on the basis of individual cylinders and the increase in the reference level is limited when a new reference level leaves a predetermined reference level range or the gradient of the sound increase exceeds a predetermined threshold value. For determination of the reference level range and/or the threshold for the gradient average values of the signals originating from the sound of other cylinders are considered.

Abstract: In the apparatus for controlling a coasting air recirculation valve of the turbocharger of an internal combustion engine, the coasting air recirculation valve is arranged in the coasting air recirculation line bypassing a compressor in the intake duct, and the coasting air recirculation valve is controllable by way of the intake duct pressure on the downstream side of the throttle valve. In order to ensure defined opening and closing of the coasting air recirculation valve, an additional control pressure, with which the coasting air recirculation valve can be opened independently of the intake duct pressure, can be delivered to the coasting air recirculation valve.

Abstract: The apparatus detects knock in an internal combustion engine with at least one knock sensor associated with a cylinder of the internal combustion engine. The apparatus initially processes the analog knock sensor output signals in an analog signal preparing device (18), which can include a multiplexer and analog/digital converter, but the actual knock detection occurs only in a purely digital signal analysis device (19), which processes the prepared and digitized knock sensor output signals. The digital signal analysis device (19) extracts at least one knock index and compares it with predetermined threshold values for knock detection, preferably considering a reference value for knock-free operation. A method of detecting knock is also described which is based on the use of this apparatus.

Abstract: A device for suppressing knocks in internal combustion engines, in which the ignition firing point is adjusted after knocking has occurred, and this knock control is only activated in response to specifiable thermal conditions in the internal combustion engine. The gas-inlet temperature in the combustion chamber of the internal combustion engine is ascertained for the valuation of the thermal conditions of the internal combustion engine and for switching the knock control into the active state.

Abstract: A method for monitoring and error detection in a device for knock detection is disclosed, in which two different diagnosis functions can be carried out in an alternating fashion. If one of the diagnosis functions gives rise to the suspicion of an error or an error correction, this diagnosis function is carried out again in order to confirm the suspicion before the other diagnosis function is carried out, wherein the renewed diagnosis is carried out at a shorter interval than usual.

Abstract: To achieve a very sturdy automatic control of the boost pressure, the integration of system deviation of the boost pressure, which is carried out by an integrator, is limited to a predefinable limiting value. Limiting value is composed of a basic value and a correction value superimposed upon it. Correction value is determined adaptively as a function of speed, a plurality of speed ranges being predefined. Adapted correction value can be increased or reduced stepwise, which mainly depends on whether the integral-action component of the manipulated variable for the boost pressure is smaller or greater than the current limiting value.