Document Type and Number:
Japanese Patent JPH0458557
Kind Code:
B2
Inventors:
KOYAMA TAKEHISA
Application Number:
JP3416785A
Publication Date:
September 17, 1992
Filing Date:
February 22, 1985
Export Citation:
Assignee:
FURUKAWA CO LTD
International Classes:
E21B1/26; E21B1/00; E21B10/60
Next Patent: JPH0458558