Patents Assigned to Opcom
  • PBX DID and E and M tie trunk integration adapter and method
    Patent number: 4792967
    Abstract: A private branch exchange (PBX) direct in dailing (DID) and an E&M tie trunk voice message integration adapter and method is disclosed. The invention permits a calling party on a DID line to a desired extension connected to a PBX to be automatically connected to the called party's mailbox in a VMS when the called extension is busy or does not answer.
    Type: Grant
    Filed: February 20, 1986
    Date of Patent: December 20, 1988
    Assignee: Opcom
    Inventors: David J. Ladd, Stevan C. Smith
  • PBX telephone call control system
    Patent number: 4783796
    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.
    Type: Grant
    Filed: November 29, 1985
    Date of Patent: November 8, 1988
    Assignee: OPCOM
    Inventor: David J. Ladd
  • PBX telephone call control system
    Patent number: 4747124
    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 or Centrex equipped) 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 conjunction with the pre-existing PBX equipment, providing expanded capabilities at a reasonable expense.
    Type: Grant
    Filed: May 6, 1985
    Date of Patent: May 24, 1988
    Assignee: Opcom
    Inventor: David J. Ladd