Mechanised retaining section.

摘要

The invention relates to coal-extraction techniques. The retaining section which is the subject of the invention is of the type comprising particularly a hydraulic jack 13 arranged in such a way that its movable element 14 is displaced transversely relative to the displacement of the movable element 10 of the hydraulic jack 7 and cooperates with the pusher 11 by means of a slide 15 connected kinematically to the sole plate 3, and is characterised in that the pusher 11 is arranged on the wall 12 and, during the displacement of the mechanised retaining section, serves as a slideway for the slide 15 which is constantly laid against the pusher 11 by the movable element 14 of the other hydraulic jack 13, of which the chamber on the piston side is constantly connected to a pressure source for this purpose, whilst the working-face part 4 of the sole plate 3 can rise above the wall in the event of a variation in the height of the hydraulic props, thus keeping the cap in contact with the roof. The invention can be used both in boom-type supports and in boom-type and shield-type supports. <IMAGE>