Method for recognizing erratic combustion

US5433107A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Anton Angermaier · Landshut, DE
• Manfred Wier · Wenzenbach, DE
• Thomas Vogt · Regensburg, DE

Key dates

• Filing date: Jun 30, 1993
• Grant date: Jul 18, 1995
• Expiry date: Jun 30, 2013

Classification

• Technology area (CPC G): Physics
• CPC primary: G01M15/11
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method is provided for recognizing erratic combustion in a multicylinder internal combustion engine by using a time measuring device to measure successive time periods which a crankshaft needs to rotate through predetermined angles during operating strokes of successive cylinders. The method includes determining a static component by using a calculating device to subtract a time period of the next cylinder in an ignition order from the time period of a cylinder to be examined. The static component is multiplied with a standardizing factor by using the calculating device. A dynamic component is determined by using the calculating device to subtract a time period of a next cylinder in the ignition order from a time period of a preceding cylinder in the ignition order, and a dynamic component is negated. A change component for a lack of smoothness value is formed, the lack of smoothness value is multiplied with a weighting factor to form a weighted value, and the weighted value is set equal to zero if the weighted value is negative. A sliding average is formed from the weighted value in a sliding averaging process. A lack of smoothness value is determined from addition of the static…