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公开(公告)号:US1711673A
公开(公告)日:1929-05-07
申请号:US9639426
申请日:1926-03-22
Applicant: BELL TELEPHONE LABOR INC
Inventor: CRAWFORD ALLEN I , SAMPLE RALPH M
CPC classification number: H01J5/54
公开(公告)号:US1711673A
公开(公告)日:1929-05-07
申请号:US9639426
申请日:1926-03-22
Applicant: BELL TELEPHONE LABOR INC
Inventor: CRAWFORD ALLEN I , SAMPLE RALPH M
CPC classification number: H01J5/54