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公开(公告)号:US2081302A
公开(公告)日:1937-05-25
申请号:US10998736
申请日:1936-11-09
Applicant: JARVIS FRANK E
Inventor: JARVIS FRANK E
IPC: E21B10/48
CPC classification number: E21B10/48
公开(公告)号:US2081302A
公开(公告)日:1937-05-25
申请号:US10998736
申请日:1936-11-09
Applicant: JARVIS FRANK E
Inventor: JARVIS FRANK E
IPC: E21B10/48
CPC classification number: E21B10/48