| 摘要 |
<p>The boom (5) has a mobile support and which supports a double boom (7). The mobile support is preferably adjustably mounted on the support (4) by means of a pivot (8). The pivot (8) is preferably positioned under the centre of gravity of the boom (5), at the bottom of the support. Between the fixed and mobile supports (6, 4) are two shock absorbers (9, 10), one of which operates whilst the other is inactive, over uneven ground. Each shock absorber (9, 10) is hinged (11) on a cover (13) over the fixed support (4). The end of its rod (14) is hinged on the mobile support (6) by means of a pin (15) which slides and turns in a slot (16) in the mobile support (16).</p> |
