Title:
DRILLING CHIP AND DRILLING BIT
Document Type and Number:
Japanese Patent JP2020076299
Kind Code:
A
Abstract:
To relieve the residual stress at an interface between a chip body and a hard layer.SOLUTION: A drilling chip comprises: a chip body 2 made of a cemented carbide having a rear end portion 2A and a front end portion 2B, each of which has a columnar shape or a disc shape centering on a chip center line C; and a hard layer 3 made of a polycrystalline diamond sintered body covering the front end portion 2B. The front end portion 2B of the chip body 2 has a convex portion 2a whose surface has a convex arc shape in a cross section taken along the chip center line C, and a concave portion 2b which has a concave arc shape and is in contact with the convex portion 2a. A diameter D (mm) of the rear end portion 2A is in a range of 8 (mm) to 20 (mm), a ratio r1/D formed by a radius r1 (mm) of the convex portion 2a to the diameter D (mm) is 0.1 to 0.65, a ratio r2/D formed by a radius r2 (mm) of the concave portion 2b is in a range of 0.05 to 3.0, and an angle θ (°) formed by a straight line L connecting a contact point P of the convex portion 2a and the concave portion 2b and a center Q of the convex portion 2a with respect to the chip center line C is in a range of 20 (°) to 90 (°).SELECTED DRAWING: Figure 1
More Like This:
| WO/2004/040096 | COMPOSITE TOOL INSERT |
| WO/2019/129716 | POLYCRYSTALLINE DIAMOND CONSTRUCTIONS |
| WO/2000/034001 | MICROWAVE BRAZING PROCESS AND BRAZING COMPOSITION FOR TSP DIAMOND |
Inventors:
TAKEUCHI YUICHIRO
MATSUO TOSHIHIKO
AHMADI EKO WARDOYO
MATSUO TOSHIHIKO
AHMADI EKO WARDOYO
Application Number:
JP2019175936A
Publication Date:
May 21, 2020
Filing Date:
September 26, 2019
Export Citation:
Assignee:
MITSUBISHI MATERIALS CORP
International Classes:
E21B10/56
Domestic Patent References:
| JPS6278394A | 1987-04-10 | |||
| JPS6391583U | 1988-06-14 | |||
| JP2003515020A | 2003-04-22 | |||
| JPS6058357B2 | 1985-12-19 | |||
| JPH03503793A | 1991-08-22 | |||
| JP2016135983A | 2016-07-28 |
Foreign References:
| US6484826B1 | 2002-11-26 | |||
| US20110031032A1 | 2011-02-10 | |||
| US5379854A | 1995-01-10 | |||
| US20020007972A1 | 2002-01-24 | |||
| US8857541B2 | 2014-10-14 |
Attorney, Agent or Firm:
Yasushi Matsunuma
Mitsuo Teramoto
Fumihiro Hosokawa
Kazunori Onami
Mitsuo Teramoto
Fumihiro Hosokawa
Kazunori Onami