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公开(公告)号:US2970023A
公开(公告)日:1961-01-31
申请号:US71711558
申请日:1958-02-24
Applicant: PERFECT CIRCLE CORP
Inventor: BERT THOMPSON
IPC: F16J9/20
CPC classification number: F16J9/20
公开(公告)号:US2970023A
公开(公告)日:1961-01-31
申请号:US71711558
申请日:1958-02-24
Applicant: PERFECT CIRCLE CORP
Inventor: BERT THOMPSON
IPC: F16J9/20
CPC classification number: F16J9/20