Framework for openings in outer walls of building, esp. transformer or switching station - has perforated plates stretching across between inner and outer girders with diagonal braces and pivoted flap

摘要

The opening in the outside wall of a building is filled with a framework which has perforated plates mounted across it between the inner and outer girders. At least one plate has a pivoted flap for a ventilator. There are several diagonal elements between these plates across the frame. The pivot for this flap is in a C- shaped groove at the join of one diagonal with the main girder that is aligned with the interior wall surface. All the joins have similar grooves for the installation of other flaps. ADVANTAGE - Prevents ingress of flood water and objects into ventilator opening.