Life safety audio system having a voice synthesizer and a constant volume telephone network
US4682348A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 16, 1985 |
| Grant date | Jul 21, 1987 |
| Priority date | — |
| Expiry date | May 16, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M11/045
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A life safety system for monitoring a building has a plurality of detectors for detecting alarm conditions located throughout the building, a plurality of speakers located throughout the building, a source of pre-stored voice messages which can be broadcast over the speakers, and a telephone network. The improvement is a voice synthesizer for providing the source of pre-stored voice messages and a constant volume telephone system. The constant volume telephone system has a telephone line and a plurality of telephones which can be connected to the telephone line, and a power supply having an adjustable output voltage which provides the voltage for the telephone line. A sensing and adjusting circuit senses the number of telephones off-hook and causes the power supply to be adjusted in response to the number of telephones off-hook.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.