Title:
掘削システム
Document Type and Number:
Japanese Patent JP3999722
Kind Code:
B2
Inventors:
Motoharu Tsukada
Application Number:
JP2003348366A
Publication Date:
October 31, 2007
Filing Date:
October 07, 2003
Export Citation:
Assignee:
Motoharu Tsukada
International Classes:
E21B21/14; E02D1/04; E21B25/00
Domestic Patent References:
| JP2002282670A | ||||
| JP59139919A | ||||
| JP10220159A | ||||
| JP63043552B2 | ||||
| JP7081478B2 | ||||
| JP2533721B2 |
Attorney, Agent or Firm:
Shinichi Naemura