Methods and apparatus for special status indication in telephone systems
US4140882A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 1977 |
| Grant date | Feb 20, 1979 |
| Priority date | — |
| Expiry date | Sep 12, 1997 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S379/909
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A telephone system usable for example in hotels or the like and in which each of a plurality of telephone sets is equipped with a special status indicator or signal light as well as the usual bell, the system being characterized in that the indicator is automatically excited without ringing the bell by voltages applied from the ring generator whose output signal is connected across the tip and ring leads of a telephone line when the latter is placed in a special status (message waiting) by a status signal in the control unit. The ring generator is constructed to produce special status indicator excitation voltages during the "bell silent" intervals of its output signal, and the indicator is periodically actuated by connecting that output signal across the tip and ring leads of telephone sets, which are in the special status, during at least a portion of such intervals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.