摘要 |
<p>The system (1) has an anchoring unit (3) that allows fixation of the system at a fixed point (30). A cord circulation device (7) circulates a cord (5) in a closed loop, and comprises a square shaped deformable element (70) that is formed by a metal rod and fixed to a fixation unit (6) that fixes the circulation device on ground, at right corner of the deformable element. The circulation device comprises circulation pulleys (73) fixed at two ends of the deformable element, and the cord passes through the circulation pulleys. The square shaped deformable element is made of a plastic material.</p> |