Call screening system
US4634811A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 1984 |
| Grant date | Jan 6, 1987 |
| Priority date | — |
| Expiry date | Jun 28, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q2213/13256
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A call screening system to be added onto and used with a PBX or Centrex telephone system having an attendant answering console. The call screening system enables incoming calls for various telephone extensions to be directed to another telephone extension in the system for screening such incoming calls. The call screening system includes a DTMF tone generator and a screening system. The DTMF tone generator is coupled to the attendant answering console for generating a first DTMF coded signal for enabling the attendant answering console to call a screening telephone extension within the telephone system and generating a second DTMF coded signal that provides an indication as to the particular telephone extension within the telephone system for the person that the incoming caller is calling. The screening system is coupled between a single tip/ring line from the PBX or Centrex and a tip/ring line to a screening telephone extension of a user screening incoming calls for other telephone extensions. The screening system receives a call from the attendant answering console when the associated screening telephone extension has been called by a generated first DTMF coded signal for such sc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.