Two-line telephone controller with hold feature
US5960065A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 14, 1996 |
| Grant date | Sep 28, 1999 |
| Priority date | — |
| Expiry date | Mar 14, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/0089
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a two-line telephone controller which includes a line select switch which operates complementarily to a force busy relay that allows an unselected telephone line to be forced to a busy state, a method for using the force busy relay also to place an active line on hold. The method includes detecting an incoming call on an inactive line, switching the line select switch to the inactive line, receiving an instruction to place the active line on hold, and responding to the hold instruction by closing an off-hook relay so as to connect the force busy switch across the active telephone line, opening a first handset select switch for the active telephone line, and closing a second handset select switch so as to select the incoming call on the ringing line. Because the force busy switch is connected across the formerly-active telephone line, loop current is maintained, thereby placing and maintaining the formerly-active call on hold.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.