Improvements in the construction of covering frames for engraving mining galleries (Machine-translation by Google Translate, not legally binding)

摘要

Improvements in the construction of lining frames for the siding of mining galleries using ribbed profiles congruent to each other in cross section whose ends intertwined in the same direction are coupled together longitudinally displaceable and whose webs are joined reciprocally by a bottom and enclosing an angle between them of opening of at least 15º, converge reciprocally towards the bottom and rest against each other in the area of overlap with surfaces directed transversely thereto, characterized in that the interior width (b1) of the bottom of the profile (2) is equal or greater that the outer width (b2) and because the thickness of the wings (3) is different in a small degree from that of the bottom (2), although only to such an extent that in the area of overlap when increasing the load the profiles by effect of its elastic or plastic deformation come to support each other also with parts of the heads (wings or bottoms) of relatively more dimensions biles. (Machine-translation by Google Translate, not legally binding)