Knock detecting apparatus for internal combustion engines
US4462247A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Mar 3, 1982 |
| Grant date | Jul 31, 1984 |
| Priority date | — |
| Expiry date | Mar 3, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S73/04
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A knock detecting apparatus for detecting the occurrence of knocking in an internal combustion engine by detecting variations in the pressure of engine cooling water. A sealed double diaphragm structure is formed by a first diaphragm which is directly responsive to variations in the cooling water pressure and not resonant at the knock frequencies and a second diaphragm which is resonant at the knock frequencies. A noncompressible fluid is contained in the sealed double diaphragm structure between the two diaphragms. Pulsations of the second diaphragm, resonant at the knock frequencies, are detected by a magnetic device or a piezoelectric device operative to output an ac signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.