| 摘要 |
<p>A boom comprises: a longitudinally extensible arm (1) having first and second opposite ends, said first end being adapted to support load (2), said second end being adapted to pivot about an axis (3) of rotation so that said arm can pivot upwards or downwards; at least one displacement means (7,8) for adjustably displacing said arm so that said arm will undergo said pivoting; and at least one sensor (12) for providing at least one signal in response to position of centre of gravity (10) of said arm. The arm can be mounted to e.g. a vehicle, especially a fork lift truck preferably, at least one of the displacement means (7,8) is hydraulic.</p> |
