| 摘要 |
Soil displacement hammer for driving holes in the ground, comprising a substantially cylindrical body, a soil displacement head at a forward end of the body, a longitudinally reciprocable striking member housed within the body, and an anvil member within the body adjacent its forward end and adapted to receive hammer blows from the striking member to cause the body to be driven forward. A retractable baffle member is mounted adjacent the forward end of the body and is movable between a retracted position in which it does not project from the body so that the soil displacement hammer describes a straight path in the ground, and an extended position in which it projects transversely from one side of the body to cause the soil displacement hammer to describe a curved path in the ground. The invention also provides a method of tracking such a soil displacement hammer in the ground. |
