Knock detecting apparatus for internal combusion engines
US4476709A · kind A · utility
8Cited by
4References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 17, 1982 |
| Grant date | Oct 16, 1984 |
| Priority date | — |
| Expiry date | Aug 17, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L23/225
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a knock detecting apparatus for an internal combustion engine, the output signal of a knock sensor whose output signal level varies in accordance with the engine conditions, engine speed, sensor sensitivity, etc., is passed through an automatic gain control circuit (AGC) thereby stabilizing the output level. The background noise level derived by integrating the output signal and the stabilized output signal are compared to detect the occurrence of knocking. The stabilized output signal is passed through a low-pass filter or a band-pass filter and the resulting control signal is used to control the gain of the AGC circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.