| 发明名称 |
Boring bit for coal or soft rock |
| 摘要 |
<p>The bit has a cutting portion 12 and a shank portion 14. One or more ridges 20 extend rearwardly from the cutting portion in spiral fashion. The ridges serve to lead drilling debris rearwardly from the cutting portion in use. <IMAGE></p> |
| 申请公布号 |
GB2199520(A) |
申请公布日期 |
1988.07.13 |
| 申请号 |
GB19870029740 |
申请日期 |
1987.12.21 |
| 申请人 |
* BOART INTERNATIONAL LIMITED |
发明人 |
FREDERICK GEORGE * HOLDEN |
| 分类号 |
B23Q11/00;(IPC1-7):B23B51/00 |
主分类号 |
B23Q11/00 |
| 代理机构 |
|
代理人 |
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| 主权项 |
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| 地址 |
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