Title:
ROCK BIT
Document Type and Number:
Japanese Patent JP3474263
Kind Code:
B2
Abstract:
PURPOSE: To prevent a drilling chip from falling off during drilling.
CONSTITUTION: A bit body 1 is formed in a cylindrical shape, and a drilling chip 5 with a wedge-shaped tool edge 5a and a center top with an injection opening 4a are provided at the top end of it. Also these center top 4 and drilling chip 5 are made of a sintered alloy formed integrally by sintering, and provide -, Y, +, and X patterns. Then a recessed top discharge groove 11 connected to the center top 4 is formed in the chip discharge part 10 of the bit body 1.
Inventors:
Katsuhiro Ito
Application Number:
JP13941494A
Publication Date:
December 08, 2003
Filing Date:
May 30, 1994
Export Citation:
Assignee:
Toshiba Tungaloy Corporation
International Classes:
E21B10/36; E21B10/46; (IPC1-7): E21B10/46; E21B10/36
Domestic Patent References:
| JP355401Y1 | ||||
| JP3633901Y1 |
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