Title:
DRILLING TOOL
Document Type and Number:
WIPO Patent Application WO/2014/080920
Kind Code:
A1
Abstract:
The present invention provides a drilling tool (1) including: an inner device (4) inserted within a casing pipe (2) in such a way as to be extendable and retractable along the centerline thereof; and a drill bit (5) attached to the distal end part of the casing pipe (2), the drill bit (5) being capable of engaging the inner device (4). The drill bit (5) has a first section (10) provided with at least one drilling member. The drill bit (5) has a wall surface (20c) against which the distal end part of the inner device (4) is capable of abutment in the centerline direction. The maximum outside diameter of a first section (19) of the drill bit (5) is greater than the outside diameter of the casing pipe (2).
More Like This:
Inventors:
KOBAYASHI NAOSHI (JP)
TAKATOU HIROSHI (JP)
TAKATOU HIROSHI (JP)
Application Number:
PCT/JP2013/081209
Publication Date:
May 30, 2014
Filing Date:
November 19, 2013
Export Citation:
Assignee:
TUNGALOY CORP (JP)
International Classes:
E21B7/20
Foreign References:
| JP4962129B2 | 2012-06-27 | |||
| JPH08312280A | 1996-11-26 | |||
| JP3903881B2 | 2007-04-11 | |||
| JP4001346B2 | 2007-10-31 |
Attorney, Agent or Firm:
TANI & ABE, p. c. (JP)
Patent business corporation A valley and Abe patent firm (JP)
Patent business corporation A valley and Abe patent firm (JP)
Download PDF: