Robert Boschgmbh

Jurgen Forster

Klaus Ries-Muller

Andrea Lohmann

Asmus Volkart

Martin Streib

Manfred Mezger

Wolfgang Wimmer

Martin Knoss

Sigrid Hafner

Berthold Steinmann

Diethard Lohr

Hartmut Dietz

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 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 and an arrangement for controlling the power of an internal combustion engine. In the method and arrangement, the power-adjusting element for adjusting the supply of air to the engine is adjusted in the context of a load control loop. When the load detection becomes disabled, measures are taken for ensuring operational reliability and an emergency method for adjusting the throttle flap is described in the fault situation.

Method and arrangement for controlling the power of 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 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.

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Chemnitz, Germany

Jurgen Forster