Security alarm transmission system
US4148019A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 5, 1975 |
| Grant date | Apr 3, 1979 |
| Priority date | — |
| Expiry date | Mar 5, 1995 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B19/00
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A security alarm transmission system for protecting a building includes a plurality of alarm transmitter units each having a transmitter circuit controlled by associated condition sensors to generate coded alarm signals which are inductively coupled to a pick-up loop extending around the periphery of the building and extended to a receiver connected to the loop which decodes the alarm signals and provides a suitable alarm indication. The alarm transmitter unit is adaptable to provide different alarm outputs for indicating fire in the building or an unauthorized entry of the building, or an emergency condition, for example. The multipurpose alarm transmitter unit comprises a housing unit for containing the transmitter circuit, the housing permitting the transmitter circuit to be controlled by normally open or normally closed switches, and a mounting assembly which permits convenient installation of the transmitter unit at desired locations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.