| 摘要 |
<p>The lower crane has a horizontal jib and a travelling trolley. This crane is able to carry high loads in comparison with its own weight and it has high mobility. The distance of the travelling trolley (7), counterweight (8) and the tips of the jib can be varied relative to each other as well as relative to the central tower (2). The jib (6) consists of a balancing jib (6a), a middle part (6b) and the working jib (6c). They are able to slide in a bearing arrangement (5) at the upper end of the central tower (2). This crane can be collapsed for road transport. Piezoelectric elements are used as safety transducers.</p> |
