Robert Boschgmbh

Audi Ag

Unisia Jecs Corporation

Klaus Ries-Muller

Manfred Mezger

Jurgen Forster

Andrea Lohmann

Asmus Volkart

Wolfgang Wimmer

Ernst Wild

Rainer Frank

Sigrid Hafner

Christian Kohler

Helmut Denz

Kenichi Machida

Andreas Blumenstock

Erich Schneider

Karsten Mischker

Martin Klenk

Robert H Entenmann

Rudi Mayer

Heinz Bohmler

Hartmut Dietz

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.

Method of diagnosing a catalytic converter and arrangement therefor

Diagnosis of electrical consumers in a motor vehicle

A first signal imaging nonuniformities in the rotational movement of the crankshaft is provided and corrective values are formed and successively changed for each cylinder individually and specifically for each load/rpm range of a plurality of load/rpm ranges until a predetermined condition is satisfied. The corrective value of the first one of the load/rpm ranges wherein the predetermined condition is satisfied is logically coupled to the first signal also in the remaining ones of said the ranges so long until the condition is also satisfied in the remaining ones of the ranges to thereby form a second signal less influenced by the nonuniformities than the first signal. A misfire is then detected when the second signal crosses over a reference value.

Method of detecting combustion misfires

The invention is directed to a method for detecting combustion misfires in an internal combustion engine having a crankshaft and a transducer wheel coupled to the crankshaft and a sensor. The combustion misfires are detected on the basis of a time-dependent trace of the rotational movement of the transducer wheel and the transducer wheel has predetermined segments which pass the sensor. In the method, a sensor is utilized to detect segment times in which the segments pass the sensor so that the sensor produces a sensor signal representing the segment times. The sensor signal is applied as an input signal to first and second lowpass filters mutually connected in parallel thereby obtaining first and second output signals which react with different speeds to changes in the input signal. The difference between the first and second output signals is formed and a measure is, in turn, formed for the changes of the difference. The measure is compared to a threshold value and a movement of the measure above the threshold value is evaluated as a misfire.

Method of detecting combustion misfires by evaluating RPM fluctuations

The invention is directed to a method for detecting combustion misfires on the basis of a first input feature signal in which the nonuniformity of the rotational movement (on the basis of rpm or segment times) of the engine is mapped within the first order. According to the method, a permanent misfire at a cylinder is preliminarily detected when a first threshold value is exceeded by the amount of a first input feature signal and a detection signal for permanent misfires at several cylinders is active (and in this way, permanent misfires at several cylinders are recognized) when a threshold value is exceeded by the magnitude of further assigned input feature signals or by the magnitude of the first feature signal when a second threshold value is exceeded. The detection signal for permanent misfires at a cylinder is always switched to be inactive when there is an active detection signal for permanent misfire at several cylinders. When there is an inactive detection signal for permanent misfire at several cylinders, the preliminary detection signal for the permanent misfire at a cylinder becomes finally active and permanent misfires at a cylinder are recognized.

Method for detecting combustion misfires at one or more permanently

The invention is directed to a method of detecting disturbances of the crankshaft rpm for an internal combustion engine which are caused by an empty tank. Uneven-running values (LU) of the engine are detected which are distributed in bands of values and the spacing between the bands of uneven-running values (LU) is computed. A quantity of the engine is detected which is relevant to the exhaust gas of the engine. A check is then made to determine whether the computed band spacing is less than a pregiven threshold spacing and whether the exhaust-gas relevant quantity lies within a pregiven threshold value interval and, if so, this data is utilized as an indication that the disturbances of the crankshaft rpm are caused by an empty tank.

Method of detecting disturbances in an internal combustion engine caused

Apparatus for monitoring the cylinders of a multi-cylinder internal

The invention is directed to a method for detecting combustion misfires on the basis of a first complex input feature signal wherein the nonuniformity of the rotational movement (on the basis of rpm or segment times) of the internal combustion engine is mapped within a first order defined by a rotation of the crankshaft through an angle of 720.degree./k wherein k=1. The input feature signal serves as a feature signal to detect recurring misfires and functions as a feature signal to detect sporadic misfires. The complex input signal is defined by a magnitude and a phase angle which vary as a function of time. The presence of a misfire is detected from the magnitude and the affected cylinder is determined from the phase angle.

Method for detecting combustion misfires via a separate classification

The invention is directed to a method for detecting combustion misfires in a multicylinder internal combustion engine. The method includes the steps of: forming a criterion for the rough running of the engine for each cylinder individually on the basis of time intervals during which the crankshaft passes through predetermined angular ranges; and, forming corrective values from rough-running values for each cylinder individually during misfire-free operation so that the rough-running values for each individual cylinder coupled to said corrective values become equal with respect to each other.

Method of detecting engine speed for detecting misfires in an internal

The invention is directed to a method for detecting misfires in the combustion of a z-cylinder four stroke internal combustion engine wherein the engine includes a transducer wheel coupled to the crankshaft of the engine and rotating in phase synchronism with the crankshaft. The transducer wheel has typically z/2 segments and the segments are scanned with a sensor device to supply a segment-time signal reflecting the nonuniformity of the rotational movement of the crankshaft with respect to individual ones of the cylinders of the engine. Rough-running values are formed for each cylinder on the basis of the segment times with each of the rough-running values including a component occurring at the frequency of the crankshaft. The component is filtered out and then the filtered rough-running value is compared to a threshold value. A misfire is determined to be present when the filtered rough-running value exceeds the threshold value.

Method for detecting combustion misfires

The invention is directed to a method for detecting combustion misfires in a multicylinder internal combustion engine. The method includes the steps of: detecting the time span ts(i) in which the crankshaft of the engine passes through a pregiven angular range (.phi.) for each ignition of the engine; computing a vector element Lut(i) for the rough running of the engine based on at least one detected time span ts(i) for each ignition (i) of the engine; forming a vector LUT(i) from at least two vector elements Lut(i), Lut(j) with the two vector elements Lut(i), Lut(j) being for each ignition (i); computing the spacing between the vector LUT(i) and at least one predetermined reference vector Rn and Ra; and, detecting a combustion misfire when the spacing satisfies a predetermined condition.

Method of detecting misfires in a multicylinder internal combustion

Adaption device for transmitter wheel of combustion engine

The invention is directed to a method for detecting combustion misfires in an internal combustion engine on the basis of a first signal wherein the nonuniformity of the rotational movement of the crankshaft of the engine is imaged. The method includes the steps of: generating a second signal which is periodic and has a period duration corresponding to one of the following: the cycle duration of a complete work cycle of the engine or the cycle duration divided by a whole number, and the second signal having a fixed phase relationship to the rotational movement of said crankshaft; providing an ancillary signal based on the first signal; modulating the second signal with the ancillary signal and filtering the second signal to form a third signal; and, utilizing the third signal for detecting the presence of misfires and for identifying the cylinder affected by the misfires.

Apparatus and method for recognizing an absence or presence of a misfire in each of cylinders of a multi-cylinder internal combustion engine without influences of a mechanical deviation in a crank angle sensor and of a combustion state deviation between each of the cylinders. A period of each reference signal (REF) is generated from the crank angle sensor and a fuel combustion state deviation between each of the cylinders. The period of each reference signal (REF), which is generated from the crank angle sensor whenever an engine crankshaft has rotated through a predetermined crank angle expressed as 720.degree./n (n denotes a number of engine cylinders), is measured by a timer. A determination of the absence or presence of the misfire in each cylinder is made based on the measured period of the reference signal for each corresponding one of the cylinders. The measured period being corrected with either or both of first and second correction coefficients (KT.sub.i KKT.sub.i) derived by learning the corresponding first correction coefficient for the mechanical deviation and by learning the corresponding second correction coefficient for the combustion state deviation.

Growing community of inventors

Bad Rappenau, Germany

Klaus Ries-Muller