The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 13, 1999
Filed:
Sep. 24, 1997
Asmus Volkart, Bietigheim-Bissingen, DE;
Klaus Ries-Muller, Bad Rappenau, DE;
Jurgen Forster, Chemnitz, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
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.