| 摘要 |
<p>The device has a longitudinal extended rotatable shaft (6), which is held by two supports, and a unit provided for rotation of the shaft. Several radial arms (9) are rigidly connected with a shaft at a distance from each other. A drop hammer (10) has a hammer head (11) and a hammer handle and is fixed at each radial arm at its outer end via a hammer joint (13). The hammer comprises of an anvil or striking handle and is designed with additional weight according to a specific equation.</p> |
