Knocking sensor
US4337640A · kind A · utility
6Cited by
7References
2Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1980 |
| Grant date | Jul 6, 1982 |
| Priority date | — |
| Expiry date | Apr 8, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R17/10
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A knocking sensor having a thin vibrating plate (10) receiving sound produced from an engine. The vibrating plate is applied with a piezoelectric element (11) which delivers electric output in proportion to the vibration. The resonance frequency of the vibrating plate is made same as the knocking frequency. A resonant tube (20) for forming resonating cavity is attached in front of the vibrating plate. A sound collector (30) is provided in front of the vibrating plate. A duct (50) is arranged between the sound collector and the sensor to improve sensitivity and freedom of mounting of the sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.