Box-section frame equipment - has walls doubled by folding sheet metal strip and supported by coupling pieces

摘要

The equipment forms a box-section frame for an air-conditioning unit etc, having profiled bars along the edges securing walls and coupled together by corner pieces with clamping pieces inserted in their ends. The bars are formed from sheet-metal bent into troughs with two outside long walls at right angles to each other, each joining onto a second short wall bent inwards at right angles. Third and fourth walls join onto the second ones, the third ones extending towards each other and ending clear of each other to form the trough mouth. The fourth walls form strips against which the unit walls bear and run parallel to the first walls, and all walls are symmetrical in relation to the line bisecting the angle between the first ones. The third walls (5) are doubled, by folding of the sheet-metal strip, and are supported in place by the clamping coupling pieces (10-14).