Abstract: A control for diagnosing a catalytic converter in the exhaust gas of an internal combustion engine having means for determining the catalytic converter temperature is presented. The diagnostic method is carried out in dependence upon the catalytic converter temperature. In the diagnosis, only such results are used which have been determined below a threshold value for the catalytic converter temperature.

Abstract: A method for diagnosing a catalytic converter (7), which is arranged in an exhaust-gas system (6) of an internal combustion engine (1) has the steps of: detecting the signal (USHK) of an exhaust-gas probe (9) downstream of the catalytic converter; forming a limit value model amplitude (AHKF) from at least one quantity (ML, n) which occurs upstream of the catalytic converter (7); forming a catalytic converter evaluation quantity (DKATI) whose value increases with increasing deviation of the amplitude (AHK) of the signal (USHK) from the limit value model amplitude (AHKF); evaluating the operability of the catalytic converter (7) on the basis of the catalytic converter evaluation quantity (DKATI); stopping the evaluation when an oxygen-dependent catalytic converter load (KATIN) exceeds or drops below a threshold value. The method is characterized in that the threshold value is pregiven in dependence upon the signal (USHK) of the exhaust-gas probe (9) rearward of the catalytic converter.

Abstract: An internal combustion engine, especially for a motor vehicle, is described, which is provided with a catalytic converter which can be charged with hydrocarbons. The converting capability of the catalytic converter can be determined by a control apparatus. The converting capability of the catalytic converter is determined by the control apparatus by means of a combination of a passive and an active diagnostic method (27, 31).

Abstract: The invention is directed to a method for evaluating the operability of a catalytic converter mounted in the exhaust-gas system of an internal combustion engine. In the method, the actual value of a signal of an exhaust-gas probe mounted downstream of the catalytic converter is detected and an expectation value of the signal of the exhaust-gas probe is formed from quantities measured upstream of the catalytic converter. A measure is formed for the deviation of the actual value from the expectation value and the operability of the catalytic converter is evaluated on the basis of the measure.

Abstract: The invention is directed to a method of diagnosing a catalytic converter mounted in the exhaust-gas system of an internal combustion engine. An exhaust-gas probe is mounted rearward of the catalytic converter and at least one misfire of a combustion of the engine is stimulated. The reaction of the exhaust-gas probe to the stimulation of the misfire is evaluated to diagnose the catalytic converter. The invention is also directed to an arrangement for diagnosing a catalytic converter.

Abstract: A method of rolling rod in which at least first and second strands are jointly rolled in a mill line having at least one final multistrand stand operating at a rolling speed which is variable as a result of predictable rolling events. Downstream of this stand the strands are separated and passed through single-strand mill stands and loops are provided upstream of the first single-strand mill stand in each line. Each loop has a loop length which can vary between a minimum and a maximum value. Before each of the rolling events occur at least one of the loop lengths is changed to an event optimizing value.

Abstract: The invention is directed to a method for evaluating the operability of a catalytic converter mounted in the exhaust-gas system of an internal combustion engine. In the method, the actual value of a signal of an exhaust-gas probe mounted downstream of the catalytic converter is detected and an expectation value of the signal of the exhaust-gas probe is formed from quantities measured upstream of the catalytic converter. A measure is formed for the deviation of the actual value from the expectation value and the operability of the catalytic converter is evaluated on the basis of the measure.

Abstract: The invention is directed to a method for adjusting the air/fuel ratio for an internal combustion engine having a catalytic converter connected downstream thereof which is capable of storing oxygen. In this method, the oxygen components in the exhaust gas of the engine are detected upstream of the catalytic converter and downstream thereof and the adjustment of the fuel/air ratio is influenced. In the method, a measure for the instantaneous oxygen fill level of the catalytic converter is determined from the above-mentioned oxygen components with the aid of a model. Data as to the state of deterioration of the catalytic converter are derived from the model parameters. The air/fuel ratio is so adjusted that the oxygen fill level of the catalytic converter is held to a constant mean level.

Abstract: In a method and apparatus for monitoring the operating capability of a catalyzer in the exhaust duct of an internal combustion engine, the operating capability of the catalyzer is assessed on the basis of the increase in temperature produced by the exothermic conversion of the exhaust gases in the catalyzer. The increase in temperature is determined with the aid of two temperature signals, the first temperature signal being produced on the basis of a measurement downstream of the catalyzer and the second temperature signal being formed with the aid of a temperature model. The temperature model may form the temperature downstream of a completely inoperational catalyzer, a catalyzer which is still just sufficiently operational, or a catalyzer which is fully operational. The assessment of the operating capability of the catalyzer is performed on the basis of criteria which are matched to the temperature model used.

Abstract: A method for monitoring the starting behavior of a catalytic conversion system by placing an apparatus in the exhaust-gas pipe of an internal combustion engine. The conversion power of the starting region can be determined from the temperature which results when an air/fuel mixture is fed to the catalytic conversion system.

Abstract: A method and device for monitoring a heating device of a sensor mounted in the exhaust system of an internal combustion engine. In assessing the working order of the heating device, use is made of the fact that a sensor heated by a heating element heats up more strongly than an unheated sensor, and that it is possible to establish, with the aid of the signals output by the sensor, whether the sensor has exceeded its minimum operating temperature. The temperature of the sensor is simulated as a function of internal combustion engine operating characteristics. The working order of the heating device can be assessed with the aid of the simulated temperature and the information as to whether the minimum operating temperature is exceeded.

Abstract: A method and device for generating a simulated signal relating to a temperature in the exhaust system of a motor vehicle. By means of a characteristic curve or a characteristic diagram, a signal for a steady state exhaust gas temperature is generated as a function of the flow rate of gas through the internal combustion engine of the motor vehicle. This signal is further processed to generate a signal for a rapid portion and to form a signal for a slow portion of the exhaust gas temperature. The signals for the two portions are superimposed with a prescribable weighting to generate a signal for the exhaust gas temperature. The signal for the slow portion can be logically connected, before the superimposition, to a correction value which depends on the speed of the vehicle.

Abstract: A method and device for forming a signal relating to a temperature in the exhaust system of an internal combustion engine. The method can be used, for example, to form a signal for the exhaust gas temperature upstream of the catalytic converter, a signal for the temperature in the catalytic converter, or a signal for the temperature downstream of the catalytic converter. The first step is to form a signal for a steady-state exhaust gas temperature as a function of at least one operating characteristic of the internal combustion engine. This signal can be subjected to a series of corrections in order to take into account parameters such as the efficiency of the internal combustion engine, the air/fuel ratio, the temperature of the intake air, the mixture flow rate, the vehicle speed, a possibly activated cylinder cutout, and the presence of condensed water in the exhaust system.

Abstract: A system for operating a heating element (114) of a ceramic sensor (112) which is arranged in the exhaust channel (104) of an internal combustion engine (100) and which can be heated by the heating element (114). If the internal combustion engine (100) is in an operating state in which it can be assumed that liquid is present in the exhaust channel (114) of the internal combustion engine (100), the heating element (114) is not activated or is triggered such that the ceramic sensor (112) is operated below a critical temperature (TSeK). Above the critical temperature (TSeK) there is a risk that the ceramic sensor (112) will be damaged due to contact with liquid.

Abstract: A method and a device for forming a simulated signal of the temperature of the exhaust gas, exhaust gas sensor or catalytic converter for an internal combustion engine. Using a temperature characteristic depending on the air mass stream, and two low-pass filters with time constants depending on the air mass stream, the exhaust gas temperature upstream from the catalytic converter, the exhaust gas sensor temperature and the catalytic converter temperature are simulated. The air mass, integrated since the time the internal combustion engine is started, is compared with two threshold values to determine whether or not there is still condensation water present in the exhaust gas channel upstream from the catalytic converter and/or in the catalytic converter itself. If condensation water is present, the simulated temperature(s) is limited to a value of approximately 50.degree. to 60.degree. C.

Abstract: A method, including an amplitude evaluation of control oscillations of the oxygen content of the exhaust gas of an internal combustion engine in front of and behind a catalytic converter, for judging the operating condition of the converter in order to determine whether the performance of the catalytic converter has deteriorated past a predetermined point. As soon as this condition is detected using the amplitude evaluation, switching is effected to the frequency evaluation for judging the functioning of the catalytic converter.

Abstract: In a method and device for monitoring a secondary-air system, a first value is determined which characterizes the secondary air stream blown by the secondary-air system into the exhaust-gas channel of an internal combustion engine. On the basis of this first value, the functioning of the secondary-air system is judged. If the first value lies within a predeterminable interval, it is concluded that the secondary-air system is operating properly. If the first value, on the other hand, lies outside of this predeterminable interval, it is concluded that a malfunction is present. The first value is determined from a second value which characterizes the stream of air fed to the internal combustion engine, from the air/fuel ratio of the mixture drawn in by the internal combustion engine, and from the air/fuel ratio prevailing in the exhaust-gas channel downstream of the place of introduction of the secondary-air line.

Abstract: The invention concerns a method for the determination of the content of a particular haemoglobin derivative in a blood sample. In particular, the invention concerns a method for the determination of the content of haemoglobin derivatives such as glycated haemoglobin which require the separate determination of the total haemoglobin content and the determination of the haemoglobin derivative in order to determine the proportion of the derivatized haemoglobin in the blood as well as a suitable haemolysis reagent for this.

Abstract: The invention is directed to a method for determining the storage capacity of a catalytic converter of an internal combustion engine with the aid of a first signal from an oxygen-indicating first probe mounted forward of the catalytic converter and a second signal from an oxygen-indicating second probe mounted rearward of the catalytic converter. The first and second signals show the change from rich to lean and vice versa and the method includes the steps of: determining the storage capacity as a quantity proportional to the time-dependent integral of an integration variable; starting the integration at a time point at which said first signal changes from rich to lean or vice versa; and, ending the integration after a time interval. The method does not need a special test operation of the engine to determine the storage capacity of the catalytic converter.

Abstract: The invention is directed to a method and an arrangement for making an on-board diagnosis of a catalytic converter. For this purpose, the lambda value of the mixture is shifted in a targeted manner and the jump reaction of a signal of a lambda probe arranged rearward of the catalytic converter is utilized in order to detect the amount of mean-value shift for which the successively reduced oxygen-deficiency input quantities or excess input quantities in the catalytic converter drop below the oxygen-storage capability thereof.