Abstract:
To reduce disturbance and interference signals, and particularly recurring disturbance signals due to vibration or out-of-round conditions of rotating elements coupled to a speed transducer, a low-pass filter (11) is connected to the speed transducer and, in addition, a high-pass filter (12) which, however, is disconnected upon sensing that the speed of the wheel or of the vehicle is below a predetermined limit, or that the anti brake-lock system unit (13) has responded. Thus, disturbance signals, and particularly periodic disturbance signal which might cause oscillatory conditions to arise in the filter and transducer circuitry, are effectively suppressed. To further increase the reliability of response, the output from the filter circuits is connected to threshold circuits with a variable threshold level in which comparators compare a peak signal with a weighted, then existing signal, so that the comparison level threshold is continuously shifted based on previously occurring peaks, so that disturbance signals are reliably excluded from affecting signal processing within the anti brake-lock system unit (13).
Abstract:
An automotive engine forming part of a motor vehicle is controlled to avoid slipping or spinning of a driven wheel by controlling the maximum rate of change of fuel which can be supplied to the engine, for example, by limiting the speed of deflection of a throttle flap (6) driven by a servo motor (7). The deflection speed, limited for example by a voltage divider (14) can be controlled as a function of operating parameters of the engine or the vehicle, for example, vehicle speed (V.sub.F), engine speed (n.sub.M), engine loading or a percentage of engine loading, actual wheel slip, actual angle or deflection position of the throttle flap, and the like. Further, non-linearities between deflection of an operator actuated pedal, such as a gas pedal (1) and actual deflection of the control flap (6) can be compensated for, for example, in a difference forming circuit (9) providing an output error signal for the servo motor (7) or by software, e.g. by recourse to non-linear characteristics stored in a table or graph. The duration of limiting can be determined by timing circuit connected to a terminal (p) for example, on the voltage divider (14). The system can be instrumented electrically (FIG. 2) or, for example, hydraulic-electrically (FIG. 3).
Abstract:
The invention relates to a method and device for diagnosing deviations in a single cylinder lambda control in an internal combustion engine having at least two cylinders and an exhaust gas sensor designed as a broadband lambda sensor, wherein a pump current is evaluated by means of a pump cell and said pump current is used at least temporarily for an individual cylinder lambda control. According to the invention, a pump voltage or a pump voltage change is determined via the pump cell in addition to the pump current and said value is transmitted to a diagnosis apparatus. Deviations in the single cylinder lambda control can thus be better diagnosed without additional material expense according to the invention, which provides advantages in particular in respect of tightened rulemaking in on-board diagnosis. A preferred application of the method is the use in internal combustion engines having multi-bank exhaust systems.
Abstract:
A procedure to calculate the Lambda value with a wideband Lambda sensor of an internal combustion engine of a motor vehicle is thereby characterized, in that from the measured pumping electricity and the sensitivities of the wideband Lambda sensor as well as the gas concentration ratios, in the lean operation an oxygen concentration and in the rich operation an oxygen deficit are determined and from these respectively a conclusion is drawn about the Lambda value using the Pischinger Formula.
Abstract:
A circuit configuration for operating a gas sensor is described, including a reference gas space in which an electrode is situated which is supplied with a reference gas pump current to maintain the concentration of the reference gas. A diagnostic system determines a concentration change of the reference gas via a change in the reference pump current and a time-based evaluation of the sensor signal of the gas sensor.
Abstract:
The invention further relates to a method and a model for modeling a discharge phase of a nitrogen oxide (NOx)-storage catalytic converter (12′) of an internal combustion engine (1). The NOx-storage catalytic converter (12′) is subdivision into an oxygen (O2)-store and a nitrogen oxide (NOx)-store and a reducing agent mass flow (msrg) is determined which charges the O2-store and the NOx-store. To model a discharge phase of the NOx-storage catalytic converter (12′), the O2-store is modeled via a first integrator for oxygen (O2) and the NOx-store via a second integrator for nitrogen oxide (NOx) and the first integrator and the second integrator are charge proportionally with the reducing agent mass flow (msrg) in accordance with an apportioning factor determined in dependence upon the O2-store content (mo2sp) and the NOx-store content (mnosp) of the NOx-storage catalytic converter (12′).
Abstract:
A method of desulfurization of a ceramic storage medium for sulfur oxides and/or nitrogen oxides situated in a gas stream, in particular a storage device for nitrogen oxides or sulfur oxides situated in the exhaust gas stream of an internal combustion engine, is described, a mixture having a low oxygen concentration being established in the gas stream to release the stored sulfur oxides. A measuring signal is recorded by an oxygen probe positioned downstream from the storage medium in a gas stream flow direction, the curve of this measuring signal being used to determine the loading of the storage medium with sulfur oxides. This method allows determination of the need for desulfurization as a function of the loading of the storage medium with sulfur oxides, to monitor and control the progress of desulfurization initiated and to check on how complete the desulfurization that is concluded has been.
Abstract:
An internal combustion engine (1), especially for a motor vehicle, is described, which has a catalytic converter (12) which can be loaded with and unloaded of nitrogen oxides. An NOx sensor (14) is provided with which NOx emissions can be measured downstream of the catalytic converter (12). The catalytic converter (12) can be only partially loaded by a control apparatus (18). An increased NOx emission can be generated forward of or in the catalytic converter (12) by the control apparatus (18). A conclusion can be drawn as to the operability of the catalytic converter (12) by the control apparatus (18) from NOx emissions measured downstream.
Abstract:
A control system and method for an internal-combustion engine with which the torque output of the internal-combustion engine can be reduced by suppressing the injection of fuel in individual cylinders in accordance with specifiable suppression patterns or by shifting the ignition firing point or the ignition angle. The suppression pattern is selected in dependence upon the desired torque reduction. The suppression of cylinders is allowed, however, only when in the case of the selected suppression pattern the number of cylinders to be suppressed per working cycle lies above a threshold value. The threshold value is selected in dependence upon the operating state of the internal-combustion engine, in particular on at least one of the following operating parameters: temperature of the internal-combustion engine, exhaust gas temperature, catalytic-converter temperature, load, rotational frequency, and a variable indicating whether a warm-up function of the internal-combustion engine has been activated.
Abstract:
A method and an arrangement for controlling the air supply to an internal combustion engine of a motor vehicle are proposed with filtered values being generated for the control of the actuating element position from input values formed in dependence upon operating parameters of the internal combustion engine and/or of the motor vehicle as values to be filtered and in which the speed of change of the actuating element position is variable in accordance with the input of the values to be filtered and the filtered values, in particular their difference, by influencing the filter characteristic and the transmission behavior.