Title:
【発明の名称】穿孔機の二重管式ドリルロツド着脱装置
Document Type and Number:
Japanese Patent JP2755787
Kind Code:
B2
Inventors:
KAWAMOTO KENJI
Application Number:
JP13824290A
Publication Date:
May 25, 1998
Filing Date:
May 30, 1990
Export Citation:
Assignee:
MITSUBISHI JUKOGYO KK
International Classes:
E21B19/24; E21B19/14; (IPC1-7): E21C9/00; E21B19/14
Attorney, Agent or Firm:
Mitsuru Oba (3 outside)