Patent search ap:("BELL TELEPHONE LABOR INC") AND inv:"DOBBIN HENRY F" Page 1

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发明授权
Electromagnetic switching device 失效

公开(公告)号：US1921430A

公开(公告)日：1933-08-08

申请号：US46216630

申请日：1930-06-19

Applicant: BELL TELEPHONE LABOR INC

Inventor： REYNOLDS JOHN N , DOBBIN HENRY F

IPC: H01H50/56 , H01H50/58

CPC classification number: H01H50/58 , H01H50/56

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