GB706448A - Beam for the support of the roof in the workings and galleries of mines - Google Patents

Abstract

706,448. Mine roof supports. LENTACKER, C. Nov. 28, 1951 [Dec. 1, 1950], No. 27881/51. Class 20 (2) Mine roof supports at the working face or arch supports for mine galleries comprise flexible members 10, Fig. 5 or Fig. 6, e.g a number of parallel linkages connected by common pins, which are applied to the roof by frames 13 supported by pit props 16, Fig. 5, or by pit props 16 and struts 38, 40, 41, Fig. 6, the arrangement being such that each flexible member extends above the neutral axis of its supporting frame so that when tensioned by roof pressure it will subject the frame to a bending stress in opposition to the bending stress due to the load of the roof. As shown in Figs. 1, 3, 5 each frame 13 comprises four parallel sets of three arms welded to a base plate 14 carried on the head of a prop 16, the ends of the arms and the centre of the frame having seatings 12 for the connecting pins 11 of the flexible member 10. Pivoted links 17, 18 at the ends of the members 10 serve for connecting the members 10 end to end by means of pins 21. A member 10 with its frame 13 is supported at the coal face without a pit prop by means of a strut 22 with one end bearing against the base plate 14 on the last pit prop erected and the other against a wedge 27 interposed between this end and the guide way 23 provided on the base plate 14 of the frame to be supported. The arch support shown in Fig. 6 comprises flexible members 10 carried on two frames 13 which abut one another at 35 and are supported by triangular uprights 38 on props 16. The assembly is strengthened by struts 40, 41 and adjusted by means of wedges 37, 42 interposed respectively between ends of the struts 40, 41 and wedge seatings 39, 44 on one frame 13 and on the bases of the uprights 38.