Vibration sensor
US4672839A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 21, 1985 |
| Grant date | Jun 16, 1987 |
| Priority date | — |
| Expiry date | Nov 21, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L23/222
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved vibration sensor of a type used to monitor the vibration and knocking level of an automotive engine or the like. The vibration sensor includes a casing having a cavity in which is received a resonant plate composed of a metal plate and a piezoelectric element. The piezoelectric element has electrodes disposed on opposite sides thereof, one abutting the metal plate. The electrode abutting the metal plate has an extended portion which passes around the edge of the piezoelectric body of the piezoelectric element, extending onto the opposite surface with a gap formed between the end of the extended electrode portion and the electrode on this opposite surface. A thin resistor, such as may be formed by a layer of a resistive paste or a chip resistor, is installed across the gap between the end of the extended electrode layer and the opposing electrode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.