Spectral knock detection method and system therefor
US6456927B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 22, 1993 |
| Grant date | Sep 24, 2002 |
| Priority date | — |
| Expiry date | Mar 22, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L23/225
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A spectral method, and corresponding system, for knock detection includes acquiring (603) spectral energy associated with vibration caused by a knocking condition from a running engine. Preferably, a sampled data system (105) acquires the spectral energy by converting an output from an accelerometer (101) into data samples (103) in a digital form. Then from the acquired spectral energy, a knock variable is derived from magnitudes of spectral components, representing a characteristic of a combustion chamber located within the running engine. In a preferred embodiment the knock variable is derived from magnitudes of spectral components related by ratios corresponding to Bessel function coefficients. The preferred embodiment includes a Digital Signal Processor (109) applying a Fast Fourier Transform method (503) to estimate a spectral content used to determine the knock variable. Then, a knock indication is provided (509) when the knock variable exceeds a magnitude of a predetermined threshold (507). Other embodiments include provision for providing a knock indication when a knock variable (703) derived from magnitudes of individual spectral components corresponding to characteristic …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.