Local combined telephone and alarm system
US6799031B1 · kind B1 · utility
28Cited by
7References
14Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 25, 2002 |
| Grant date | Sep 28, 2004 |
| Priority date | — |
| Expiry date | Jan 2, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M11/04
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
The invention concerns a local combined telephone and an alarm system comprising a central base communicating through two-way radio channel, according to a multiple access communication protocol, with telephone stations and detectors adapted to detect an emergency situation. The base transmits at regular intervals of less than 10 minutes, scanning messages addressed to the detectors and determines whether the detectors are operating, depending on whether it receives clearance messages from the detectors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.