Patent search ap:("GEN ELECTRIC") AND inv:"RAYNOLDS DAVID W" Page 1

1.

发明授权
Sound recording apparatus 失效

公开(公告)号：US1896851A

公开(公告)日：1933-02-07

申请号：US43752130

申请日：1930-03-20

Applicant: GEN ELECTRIC

Inventor： RAYNOLDS DAVID W , SCHWARZHAUPT PAUL J

IPC: G07F11/00 , G07F17/30 , G11B3/36

CPC classification number: G07F17/30 , G07F11/00 , G11B3/36

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