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公开(公告)号:US2650638A
公开(公告)日:1953-09-01
申请号:US16562350
申请日:1950-06-02
Applicant: IBM
Inventor: JOHNSON CURT I , NORD JAMES A
IPC: B21F3/04
CPC classification number: B21F3/04
公开(公告)号:US2650638A
公开(公告)日:1953-09-01
申请号:US16562350
申请日:1950-06-02
Applicant: IBM
Inventor: JOHNSON CURT I , NORD JAMES A
IPC: B21F3/04
CPC classification number: B21F3/04