| 摘要 |
Framework truss with changeable cantilever length, comprising an articulated grid structure which is hingedly secured at two fixed points against a wall or any other carrier element. Said framework truss is characterized in that at least two articulated grid panels are joined together having the shape of a parallelogram and projecting in the cantilever direction (L) from two fixed articulation points (A, B) situated at a certain interval (h) from each other. The articulated grid panels are comprised of parallel articulated bars (21, 22, 23, 24, 25 and 26), as well as coupling rods (31, 32, 33) connecting them by pairs from their ends between the articulation points (C1, D1; C2, D2; C3, D3) and of which the length remains always equal to the interval (h) separating the fixed articulation points (A, B). At least one point (B) of the fixed articulation points (A, B) is connected to the diagonally opposite articulation point (D3) of the terminal coupling rod (33) and used at the same time as a charge induction member, of the last articulated grid panel in the cantilever direction (L) by at least one expansion-free cable (4) which passes or is brought along diagonals of similar direction of articulated grid panels and between these diagonal segments, along the coupling rod, respectively the coupling rods (31, 32). |
