Circuitry for providing call override in a PBX system
AssigneeWestern Electric Company, Inc.
InventorEdward Walter Sobanski
Life of this patent
Estimating the term…
Abstract
In a telephone switching system wherein a plurality of line circuits are terminated in station sets, the line circuits are interconnectable to a plurality of trunk circuits through a multistage switching network. A call originated by a calling party to a called party, engaged in a conversation with a third party, is completed by overriding the conversation between the called party and the third party provided the calling party is equipped with a class of service which permits call override. Call override is initiated by the calling party upon receipt of a busy tone by a flashing of his switchhook.
Claims13
In a telephone switching system having a plurality of line circuits terminated in station sets, said line circuits being interconnectable to a plurality of trunk circuits through a multistage switching network, the invention comprising call override circuitry for completing a connection between a calling station and a called station said called station being busy as a result of a connection to a third station, said call override circuitry comprising
- means for determining a class of service provided to said calling station,
- means for detecting a busy condition of said called station,
- means for providing a through connection path from said calling station to said busy called station, said through path connection means including
- a call override trunk circuit,
- means for seizing said call override trunk circuit provided said calling station has a class of service permitting call override, and
- means for enabling said call override trunk circuit in response to a switchhook flash from said calling station.
Circuitry for controlling the establishment of call override connections between an entitled calling station and a busy called station, said called station being busy as a result of a connection to a third party station, said circuitry comprising
- means, responsive to a call from said entitled station to said called station, for detecting a busy condition of said called station,
- means, subsequently activated by said detecting means and responsive to a switchhook flash from said entitled station, for effecting the establishment of call override connections between said entitled station and said busy station, and
- means, enabled by said called station, for excluding said third party station from said call override connections.
Call override circuitry comprising
- means for seizing said circuitry in response to a call from an entitled calling station to a busy called station, said called station being busy as a result of a connection to a third party station,
- means, responsive to a receipt of a switchhook flash from said calling station, for establishing call override connections between said calling station and said called station, and
- means, enabled by said called station, for excluding said third party station from said call override connections.
Call override circuitry comprising
- means for seizing said circuitry in response to a call from an entitled calling station to a busy called station,
- means, responsive to a receipt of a switchhook flash from said calling station, for establishing call override connections between said calling station and said called station, said call override connections extending connections to another station connected on a prior call to said called station,
- means, activated by said establishing means, for supplying a call override signal over said call override connections to said calling and called stations for a predetermined time interval,
- means, responsive to a call disconnect signal from said called station which controls a release of call connections to said other station, for holding said seizure of said call override circuitry and said call override connections to said calling and called stations for a predetermined time interval following said call disconnect signal.
Dependencies are inferred from the claim text.