Tamper resistant magnetic contact apparatus for security systems
US6963281B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 1, 2001 |
| Grant date | Nov 8, 2005 |
| Priority date | — |
| Expiry date | Sep 25, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H36/0046
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A tamper resistant magnetic contact switch apparatus for alarm systems that has a plurality of magnetic reed switches configured in a logic circuit and a magnetic pack for actuation. A magnetic shield disposed around the switches defines an actuation zone. In combination with the magnetic shield preventing magnetic fields from reaching the switches from locations outside the actuation zone, the magnet pack activates two of the five switches when positioned within the actuation zone to complete the logic circuit. The magnet pack does not, however, activate any of the other switches. If any of the other three switches are activated, or if either of the two activated switches are deactivated, the logic circuit is broken and the alarm circuit is activated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.