-
公开(公告)号:US1464585A
公开(公告)日:1923-08-14
申请号:US55908722
申请日:1922-05-06
Applicant: RASMUSSEN CHESTER A
Inventor: RASMUSSEN CHESTER A
CPC classification number: E21B33/04 , E21B2033/005
-
公开(公告)号:US1842116A
公开(公告)日:1932-01-19
申请号:US44412030
申请日:1930-04-14
Applicant: RASMUSSEN CHESTER A
Inventor: RASMUSSEN CHESTER A
IPC: E21B33/1295
CPC classification number: E21B33/1295
-
公开(公告)号:US1664643A
公开(公告)日:1928-04-03
申请号:US11895526
申请日:1926-06-28
Applicant: RASMUSSEN CHESTER A
Inventor: RASMUSSEN CHESTER A
IPC: E21B33/06
CPC classification number: E21B33/06
-
-