Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
POSITIONING DEVICE OF BIT
Document Type and Number:
Japanese Patent JPH05222889
Kind Code:
A
Abstract:

PURPOSE: To bore a lower hole and form a slit in a specified direction by providing a flute cylindrical body into which a slit forming bit is drawn in the case of the withdrawing of a boring bit, and pushing forward the cylindrical body.

CONSTITUTION: A boring rod 35 provided to a drill is inserted in a cylindrical body 15, and a preceding bit 39 and a slit forming bit 40 are mounted to an adapter 37 of the front end. When direction of a blade of the bit 40 is adjusted by the slope of a boom to operate the drill, the rod 35 moves forward to influence no backward pulling capacity on the cylindrical body 15. A lower hole is bored by the preceding bit 39 in a state to bring the front end of the cylindrical body 15 into contact with a bedrock by a spring 32. Successively, a slit is formed in a specific direction by the slit forming bit 40. In that process, the rear thereof is still in the cylindrical body 15, the rear of the blade is fitted to a groove 16, and the direction of the slit remains unchanged.


Inventors:
AKIYOSHI NAOYOSHI
KUNITAKE SEIJI
TSURUTA RYUJI
Application Number:
JP1991000215859
Publication Date:
August 31, 1993
Filing Date:
July 31, 1991
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
NISHIMATSU CONSTR CO LTD
TOHO KINZOKU KK
International Classes:
E21B19/08; E21B19/087; (IPC1-7): E21C5/00
Attorney, Agent or Firm:
菅原 弘志