Patent search ap:("BELL TELEPHONE LABOR INC") AND inv:"GREENMAN ROBERT R" Page 1

1.

发明授权
Remote telephone on-hook,off-hook control 失效
Title translation: 远程电话挂机，离线控制

公开(公告)号：US3489860A

公开(公告)日：1970-01-13

申请号：US3489860D

申请日：1966-06-30

Applicant: BELL TELEPHONE LABOR INC

Inventor： GREENMAN ROBERT R , KREBS LUTHER E

IPC: H04M1/82 , H04M1/00 , H04M1/02

CPC classification number: H04M1/82

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