Glass break detection using multiple frequency ranges
US5552770A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 10, 1995 |
| Grant date | Sep 3, 1996 |
| Priority date | — |
| Expiry date | Mar 10, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/1672
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
Apparatus and a method for detecting glass breaking from an impact. Low frequencies are detected that are characteristics of the glass flexing from the impact, and high frequencies are detected that are characteristic of a) the sound of the impact and b) the glass breaking. An alarm signal is issued when the low and high frequencies occur in a predetermined sequence, and have appropriate durations, that are characteristic of glass breaking events. More specifically, the alarm sounds only when low frequencies are detected not before the high frequencies are first detected but within a predetermined time period after the first detection of the high frequencies.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.