| 摘要 |
The support arm (11) between the first outer end and a second outer end is vertically hinge-connected to the lower part (10). The support arm in an area near the first outer end has devices for supporting on the ground. Near the second outer end of the support arm is a counterweight. The support devices have comonents for supporting on a parapet (2) of a flat roof (1) of a building. |
