| 摘要 |
<p>The system has a base arm (13) complimentary to a base arm (12), and stiffeners (20, 21) fixed to arm (13) to connect the arms. The arm (12) is pivotally mounted on the stiffeners to rotate relative to the arm (13). Each stiffener has a graded drilling to adjust an angular position of the arm (12) with respect to the arm (13). Keys (15, 16) are engage in the drillings to fix the arms in selected angular position. An independent claim is also included for a scaffolding structure mounted in roofing and/or in construction work.</p> |
