Title:
DRILL JUMBO
Document Type and Number:
Japanese Patent JPS5513366
Kind Code:
A
Inventors:
YAMAUCHI NORIO
Application Number:
JP8637378A
Publication Date:
January 30, 1980
Filing Date:
July 14, 1978
Export Citation:
Assignee:
YAMAUCHI KOGYO KK
International Classes:
E21B7/02; E21B15/00; E21B19/08; (IPC1-7): E21C11/02
Domestic Patent References:
| JPS5069822A | 1975-06-10 | |||
| JP51150204B |