Title:
【発明の名称】アースドリルの過負荷防止装置
Document Type and Number:
Japanese Patent JP2754945
Kind Code:
B2
Inventors:
OOHASHI HIROSHI
IDA YOSHITAKA
IDA YOSHITAKA
Application Number:
JP11956891A
Publication Date:
May 20, 1998
Filing Date:
March 27, 1991
Export Citation:
Assignee:
SUMITOMO KENKI KK
International Classes:
B66C13/16; B66D1/54; E21B7/00; E21B15/00; E21B44/00; E21B44/06; (IPC1-7): E21B7/00; E21B15/00
Attorney, Agent or Firm:
Soyama Saburo