Piezoelectric vibration detector for sensing a nearby intruder
US4194194A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 30, 1978 |
| Grant date | Mar 18, 1980 |
| Priority date | — |
| Expiry date | Jan 30, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/169
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An intrusion sensor uses thin film piezoelectric transducers to sense nea mechanical vibrations. A hose-like sheath contains a pair of insulating strips which carry conductive leaves on their outer surfaces. A series of longitudinally arranged segments of a thin film piezoelectric material are coupled to the leaves to provide signals representative of impinging mechanical vibrations. Since adjacent ones of the thin film segments are alternately polarized, signals are created only when the vibrations are nearby. Greater sensitivity to nearby vibrations is assured when each of the segments is fabricated from several layers of the thin film piezoelectric material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.