Patent ID: 6529817
Filing Date: 2003-03-04
Classification: G01L

Abstract:
An apparatus for detecting knock in an internal combustion engine, said apparatus comprising:a plurality of knock sensors (10, 11) for detection of the presence of oscillations produced by knocking combustion in the internal combustion engine and for generation of respective analog output signals (S1, S2) according to said oscillations; analog signal processing means (18) for processing said respective analog output signals (S1, S2), said analog signal processing means for said processing including at least two symmetric knock sensor inputs (E1, E2) for said respective analog output signals, a multiplexer and an analog/digital converter for converting said corresponding analog output signals into a digital output signals; and digital signal analysis means (19)comprising means for analyzing said digital output signal and means for determining whether or not knock is occurring from said digital output signal, wherein said digital signal analysis means (19) includes at least one digital filter (20), a rectifier (21) and an integrator (22) connected in series with each other, so that said rectifier (21) processes a filtered signal from the at least one digital filter and produces a rectified filter signal and said integrator integrates said rectified filtered signal.