Patent search ap:("BELL TELEPHONE LABOR INC") AND inv:"RODKIN DENNIS L" Page 1

1.

发明授权
Pbx telephone system wherein switch units served through different central offices are controlled by control unit at one central office 失效
Title translation: 通过不同中央办公室服务的集团电话系统由一个中央办公室的控制单元控制

公开(公告)号：US3544728A

公开(公告)日：1970-12-01

申请号：US3544728D

申请日：1968-05-13

Applicant: BELL TELEPHONE LABOR INC

Inventor： RODKIN DENNIS L , WEBER LAURANCE A

IPC: H04Q11/04 , H04M7/14

CPC classification number: H04Q11/0407

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