PBX and adjunct using multi-frequency tones for communication therebetween

Patent 4879743 Issued on November 7, 1989. Estimated Expiration Date:

October 3, 2008. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

3264415

3443032

Communication system call coverage arrangements
Patent #: 4150257
Issued on: 04/17/1979
Inventor: Fenton , et al.

Telephone electronic answering device
Patent #: 4304968
Issued on: 12/08/1981
Inventor: Klausner , et al.

Multiple use digital tone generator in telephone
Patent #: 4571462
Issued on: 02/18/1986
Inventor: Janssen

Integrated message service system
Patent #: 4646346
Issued on: 02/24/1987
Inventor: Emerson , et al.

PBX telephone system I/O interface Patent #: 4674082
Issued on: 06/16/1987
Inventor: Flanagin , et al.

Inventors

Assignee

Application

No. 252477 filed on 10/03/1988

US Classes:

379/142.13, Adaptive module coupled to telephone line or telephone device379/88.26, Recording voice message from non subscriber caller379/207.07, Transition from on-hook to off-hook (e.g., idle to busy)379/207.14, Dialed number identification service (DNIS)379/207.15, Automatic number identification or calling number identification (ANI or CLID)379/214.01, Secretarial or answering service379/235, Voice frequency signalling over trunk379/376.01, Visual indication of incoming call (e.g., LED or light bulb)379/903, PASSWORD379/914, PROGRAMMABLE TELEPHONE COMPONENT379/917VOICE MENUS

Examiners

Primary: Dwyer, James L.

Attorney, Agent or Firm

Caccuro; John A.

International Class

H04M 007/06

Abstract

A PBX system is responsive to an incoming call which is directed to an adjunct of the system for sending a ringing signal over a station facility to the adjunct. When the adjunct goes off-hook, the system outputs to the adjunct over the station facility multi-frequency tones containing information associated with the incoming call prior to establishing a connection between the adjunct and calling party. The information selects the proper operating mode of the adjunct and provides other call processing information to the adjunct. The adjunct communicates information to the PBX using a switch-hook flash and multi-frequency tones.