Method and apparatus for recognition of knocking in an internal combustion engine

US4565087A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Eckart Damson · Stuttgart, DE
• Martin Klenk · Munich, DE
• Winfried Moser · Ludwigsburg, DE
• Heinz Moller · Stuttgart, DE

Key dates

• Filing date: May 23, 1984
• Grant date: Jan 21, 1986
• Expiry date: May 23, 2004

Classification

• Technology area (CPC G): Physics
• CPC primary: G01L23/225
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Engine knock sensor signals are amplified, band-pass filtered and rectified and then a sequence of integrated signal peak values are compared with reference signals relating to a typical engine knock signal. If the deviation of the integration values or peak values or their sum over a measurement period differs by less than a predetermined amount from the corresponding reference values, a knock indication is produced. The initial integration or peak value may be given less weight than those that follow. The knock sensor may be an engine block sound sensor, or a combustion chamber light, pressure or iron current sensor. Additional criteria, such as the interval between null transitions or signal maxima or the number of them in a measuring period may be used to inhibit a knock indication in case the main processing should occasionally provide an anomalous knock signal, but this precaution is not sufficiently needed to warrant its inclusion in simplified systems.