| 摘要 |
A pile driver includes an anvil 26, a reciprocating mass 11, a cushion 28 and a tubular casing 1. The mass is lifted by hydraulic means 15, 17 and released to impact the anvil via the cushion. The casing is open ended and maintains the alignment of the various components. There may be a second sound barrier 31 around the cushion separate from the casing to reduce noise. The second sound barrier may include sound dampening means such as annular bearing rings 27. |
