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公开(公告)号:US2684761A
公开(公告)日:1954-07-27
申请号:US35910653
申请日:1953-06-02
Applicant: DOWNING ROSS E
Inventor: DOWNING ROSS E
IPC: B03C1/20
CPC classification number: B03C1/20
公开(公告)号:US2684761A
公开(公告)日:1954-07-27
申请号:US35910653
申请日:1953-06-02
Applicant: DOWNING ROSS E
Inventor: DOWNING ROSS E
IPC: B03C1/20
CPC classification number: B03C1/20