摘要 |
<p>The self-erectable tower crane can be taken to site in the form of a single, collapsed transport unit. It has a large capacity boom which can be moved by a crane carriage. The boom is made up of three elements which can be tuned with respect to each other, a shoulder element (1A), a middle element (1B) and a tip element. Between the middle element and the tip element is a joint with a vertical axis, which allows a relative rotation of the tip element in one plane. Between the shoulder element (1A) and the middle element (1B) is a linkage system with five degrees of freedom. The bottom section (4A) of the column is connected with the rotary frame (8) of the crane by joint with a horizontal axis. The top section (4b) of the column is connected with the shoulder element (1A) at the boom (1) by another joint.</p> |