Patent search ap:("BELL TELEPHONE LABOR INC") AND inv:"O'BRIEN LAURENCE A" Page 1

1.

发明授权
Teletypewriter equipment 失效
Title translation: 电传打字机设备

公开(公告)号：US2275798A

公开(公告)日：1942-03-10

申请号：US23207038

申请日：1938-09-28

Applicant: BELL TELEPHONE LABOR INC

Inventor： O'BRIEN LAURENCE A , SMITH EDWARD M

IPC: H04L13/06

CPC classification number: H04L13/06

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