发明名称 |
HYDRAULIC DOWN-THE-HOLE DRILLING MACHINE |
摘要 |
A hydraulic down-the-hole drilling machine including a piston (8) that seen from the inlet (24) of the machine has a first (9), a second (10) and a third (11) piston portion with consecutively increasing diameter. To the third piston portion (11) is connected a fourth piston portion (12) having a smaller diameter than the third piston portion. The first piston portion (9) has a first pressure surface (14) that together with a second pressure surface (15) of the second piston portion (10) has a larger area than a third pressure surface (16) of the third piston portion (11), said third pressure surface (16) facing in the opposite direction and having a larger area than the first pressure surface (14). |
申请公布号 |
WO9212323(A1) |
申请公布日期 |
1992.07.23 |
申请号 |
WO1992SE00003 |
申请日期 |
1992.01.08 |
申请人 |
SANDVIK AB;AQUAPACT AB |
发明人 |
BERGQUIST, ARNE;LEIDVIK, MARTIN;NOREN, PAUL |
分类号 |
B25D17/06;E21B1/26;E21B4/14 |
主分类号 |
B25D17/06 |
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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