Title:
DRILLING APPARATUS FOR POSITIVE AND REVERSE IMPACTION
Document Type and Number:
Japanese Patent JPS5858392
Kind Code:
A
Inventors:
ISHII NOBORU
FUJIKAWA KOUZOU
YASUMORI TOSHIYUKI
FUJIKAWA KOUZOU
YASUMORI TOSHIYUKI
Application Number:
JP15770281A
Publication Date:
April 06, 1983
Filing Date:
October 03, 1981
Export Citation:
Assignee:
TOYO KOGYO CO
International Classes:
E21B44/00; E21B1/00; (IPC1-7): E21C5/00
Attorney, Agent or Firm:
Aoyama