Branched telephone system

• US 5,022,068 A
• Filed: 03/02/1988
• Issued: 06/04/1991
• Est. Priority Date: 03/05/1987
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Fujisaki, Hisashi, Shimada, Keiko
• Primary Examiner(s): Dwyer, James
• Application Number:
  US07/162,878
• Time in Patent Office: 1,189 Days
• Field of Search: 379/61, 379/62, 379/63, 379/58, 379/168, 379/184, 379/161, 379/185
• US Class Current: 455/463
• CPC Class Codes: H04M 1/715 using two or more extensions per line cordless telephones H04M1/725
• CPC Class Codes: H04M 1/725 Cordless telephones user interfaces specially adapted therefor H04M1/724

Abstract

A branched telephone system having a plurality of telephones which are connected to a single subscriber line or to single radio apparatus functions to establish a priority set condition in which the communicating function of particular one of the telephones is validated to prevent the other telephones from being used, and further includes the function of automatically cancelling such a priority set condition.

Claims

1. A branched telephone system having a plurality of telephones which are connected to equipment, comprising:

priority setting means responsive to a control signal for establishing a priority set condition in which a particular one of said plurality of telephones is usable and with the other of said plurality of telephones being invalidated in function, said plurality of telephones being usable during conditions other than when said particular one telephone is in said priority set condition;

switch means for manually generating said control signal; and

priority cancelling means for cancelling said priority set condition by detecting a change in an on-hook/off-hook condition of said particular telephone.

2. A branched telephone system as claimed in claim 1, wherein said function of said other telephones of said plurality of telephones comprises at least one of a communicating functions and a dial displaying function.

3. A branched telephone system as claimed in claim 1, further comprising indicator means for displaying said priority set condition.

4. A branched telephone system as claimed in claim 3, wherein said equipment comprises a single radio equipment and said system is mounted on a vehicle and wherein said particular one of said plurality of telephones is disposed in the vicinity of a rear seat and said other telephone is disposed in the vicinity of a front seat.