Facsimile and voice communications interface device

Abstract

An interface device allows a telephone (P.sub.1) and a facsimile (F) to effectively share a common telephone line. When an incoming call is detected (10) a check is performed to determine if either the facsimile or telephone are off hook (12). The interface device connects the call and a local ringer (66) generates ringing signals (16) which are sent to the caller. While the rings are occurring, the interface device senses for a tone characteristic of a facsimile transmission (18). If a tone is detected, the call is connected (34) to the facsimile (F) with the local ringer (66) activating the facsimile (F). If a tone is not detected, the call is connected (22) to the phone (P.sub.1) with the local ringer (66) alerting the called party that an incoming voice call has been received. When the call is completed (28), the interface unit is reset to receive another telephone call. If the call is never connected, i.e., if the caller hangs up, a dial tone sensor (78) detects for a dial tone on the telephone line. After a dial tone is detected, the local ringer (66) is deactivated and the interface unit is reset to receive another telephone call.

Dependencies are inferred from the claim text.