GB830704A - Improvements in mine roof supports - Google Patents

Abstract

830,704. Mine roof supports. RHEINSTAHL WANHEIM G.m.b.H., [formerly EISENWERK WANHEIM G.m.b.H.]. Oct. 17, 1957 [Oct. 19, 1956], No. 32487/57. Class 20(2) [Also in Group XXX] A mine roof support comprises a forward group of two hydraulic props 3, 4 adjacent a conveyer 2 and a rear group of props 5, 6, 7, 8, with a hydraulic jack consisting of three telescopic tubes 31, 32, 33 connected to both groups for advancing them in push-pull fashion between an abutment and the conveyer 2. The props of the rear group are connected by rubber pads 27 and support roof bars 16 joined by a protective plate 18. Bars 19 slidably mounted in the bars 16 are hinged to further roof bars 21 supported on the forward props 3, 4. Tubes 37, 38 carried by the conveyer 2 are opened by controls 43, 44 in the box feet 11 of the props and by another control (not shown) at the head of tube 33 to supply pressure fluid to expand or contract the tubes 31, 32, 33 within the rubber bushes 29, 30 to advance either group of props or the conveyer and set and release the props. Pressure chambers A, B, C and D of'the tubes are formed by the tubes 31, 32, 33 and internal tubes 46, 48, 49, the supply tubes 37, 38 being connected to chambers C and D and the controls 43, 44 to the chambers illustrated in Fig. 2. The tube 33, Fig. 1 is connected to the conveyer 2 by a strap 35 articulated at 34 to take up lateral deviations. The control members may alternatively be outside the support.