Rise and fall door with counter weight - has reserve ropes with different connection points on the counter weight

摘要

Door and counterweight are connected via suspension ropes. Each rope has an associated parallel reserve rope. The reserve ropes are connected to the counterweight at different points from the suspension ropes. The counterweight carries two side inverted pivots, which have lever arms of different length. The suspension ropes are connected to the ends of the shorter arms, while the reserve ropes are fastened to the longer arm ends. The counterweight is supported via axes which are arranged in an unstable manner on the two trapezoid shaped pivots.