Screen for burglar alarms and method of making the same
US4999608A · kind A · utility
18Cited by
7References
24Claims
0Family size
Inventor
Key dates
| Filing date | Jul 19, 1989 |
| Grant date | Mar 12, 1991 |
| Priority date | — |
| Expiry date | Jul 19, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/126
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An electrically conductive security screen includes an electrical resistance sensor and alarm to detect tampering with the screening material of a window. An elongated path of flexible and electrically conductive coating composition is applied to the screening material in a predetermined and non-overlapping pattern, such that a closed circuit loop is formed when it is attached to the sensor alarm; the coating having an electrical resistance that varies when it is distorted or its path interrupted. The pattern having a marginal section of high electrical resistance and being in series with at least one switch.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.