发明名称 |
Percussive down-the-hole hammer and a drill bit therefor |
摘要 |
In an air actuated down-the-hole hammer for rock drilling, a piston reciprocates within a casing to impact against a rear anvil surface of a drill bit. A foot valve extends axially between the piston and the drill bit. The anvil surface is inclined downwardly in a radially outward direction to cause liquid on the anvil surface to be discharged in a direction away from the foot valve, to prevent damage to the foot valve which could occur if piston impacts were able to create high-speed liquid streams contacting the foot valve.
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申请公布号 |
US6125952(A) |
申请公布日期 |
2000.10.03 |
申请号 |
US19990261615 |
申请日期 |
1999.03.03 |
申请人 |
SANDVIK AB |
发明人 |
BECCU, RAINER;AASBERG, BENGT |
分类号 |
E21B4/14;E21B10/38;E21B17/07;E21B21/10;E21B21/14;(IPC1-7):E21B4/14 |
主分类号 |
E21B4/14 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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