Interactive piezoelectric knock sensor
US4254354A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 2, 1979 |
| Grant date | Mar 3, 1981 |
| Priority date | — |
| Expiry date | Jul 2, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L23/222
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A piezoelectric knock sensor comprises a flexing plate at one end of a generally cylindrical case with a mounting stud extending perpendicularly therefrom and a piezoelectric element attached to the flexing plate within the case for flexure with the flexing plate. When the sensor is attached to a component of a multicylinder, internal combustion engine, the case vibrates interactively with at least a portion of the component through the flexing plate and exhibits both an interactive resonance with the component for a wide resonance peak and response to transverse as well as axial vibrations. The sensor is thus capable of resonant response to knock-induced vibrations from all the cylinders even if the characteristic knock frequencies of the individual cylinders differ over a range too great to be encompassed by a self-resonant sensor. In addition, the sensor has the comparatively high output level of a piezoelectric device and simple construction suitable for mass production.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.