PBX telephone call control system
US4783796A · kind A · utility
98Cited by
8References
17Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Nov 29, 1985 |
| Grant date | Nov 8, 1988 |
| Priority date | — |
| Expiry date | Nov 29, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M2215/745
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A PBX telephone call control system is disclosed. The system provides a line interface unit connection between a plurality of subscriber line extensions and a private branch exchange (PBX) switching equipment. The call control system appears to the PBX like any other telephone extension within the office environment and provides the user with more features in conjuction with the pre-existing PBX equipment, providing expanded capabilities at a reasonable expense.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.