US 7,621,172 B2 · Knocking determination device for internal combustion engine

Abstract

An engine ECU 200 includes a bandpass filter (1), a bandpass filter (2), and a bandpass filter (3). The bandpass filter (1) extracts only vibrations at a first frequency band A from the vibrations detected by a knock sensor. The bandpass filter (2) extracts only vibrations at a second frequency band B from the vibrations detected by the knock sensor. The bandpass filter (3) extracts only vibrations at a third frequency band C from the vibrations detected by the knock sensor. The first to third frequency bands A-C are identical in bandwidth. The engine ECU calculates a peak value in magnitude of vibrations in a synthesized waveform of these frequency bands, and determines whether knocking occurred or not based on the peak value.

Claims3

Dependent claims

A knocking determination device for an internal combustion engine, comprising:

a vibration detecting unit that detects vibrations of an internal combustion engine;
an extracting unit that extracts, from said detected vibrations, vibrations at a plurality of frequency bands being identical in bandwidth;
a determining unit that determines whether knocking occurred in said internal combustion engine or not, based on said extracted vibrations;
a detecting unit that detects a vibration waveform with predetermined crank angle intervals, based on said extracted vibrations;
and
a storage unit that stores in advance a vibration waveform of said internal combustion engine, wherein
said determining unit determines whether knocking occurred in said internal combustion engine or not, based on a result of comparison between said detected waveform and said stored waveform.

4 more elements

Dependencies are inferred from the claim text.

Knocking determination device for internal combustion engine

Life of this patent

Knocking determination device for internal combustion engine

Life of this patent

Abstract

Claims3