| 摘要 |
<p>A barrier, barrier system and components for constructing barriers about the perimeter of a roof under construction. One component is a scaffolding unit (710) adapted for use in the construction of dwelling house. The unit includes an upstanding elongate support stand (711) having a main member (712) constructed of rectangular hollow section steel (RHS) having a front wall (712a), a rear wall (712b) and two opposed side walls (712c and 712d), the main member being intended to stand adjacent the external face of a wall frame with the front and rear faces parallel thereto. A sleeve member (714) is welded to the upper end of the support member with its axis parallel to the side faces of the main member and is adapted to receive a bracket (715) which is adapted to engage with the top plate of a wall frame. Sleeve member (727) is comprised of a front plate (727a) adapted to engage with the front wall (712a) of the main member, a rear plate (727b) adapted to engage with the rear wall (712b) and two spaced apart side plates (727c and 727d) adapted to slidingly engage with the side walls (712c and 712d) respectively. The rear plate extends downwardly over much less than half the vertical length of the sleeve member and is spaced vertically from the front plate so that most of the rear face and the front face of the sleeve member are open. In use, the front and rear plates engage with the front and rear walls of the main member when the plank support members are in the horizontal attitude. The front and rear plates may bind with the front and rear walls when sufficient load is applied downwardly on the plank support members, and the height of the frame assembly relative to the main member can be adjusted by simply removing pin (728) tilting the plank support members upwardly so that the front and rear plates disengage from the main member allowing the sleeve member to slide easily therealong.</p> |
