GB766537A - Improvements in mine roof supports - Google Patents

Abstract

766,537. Mine roof supports. COAL INDUSTRY (PATENTS), Ltd. May 25, 1954 [Feb. 25, 1953], No. 5300/53. Class 20(2) A number of mine roof supports A, B, C, D, Fig. 1, each comprising a triangular base plate 2, Fig. 2, three fluid pressure operated extensible props 1 mounted at or adjacent the corners and a triangular roof plate 3, are interconnected by fluid-pressure operated rams 5 so that they may be moved under control from a remote point by releasing the pressure on the props of some supports B, D, applying pressure to extend the rams connecting'these supports to supports A. C. E, which are still fixed, re-applying the pressure to the supports B, D after movement, releasing the pressure on the remaining supports A, C, E and drawing them into the initial relative position in the same way. The rams 5 are double acting being extended by pressure applied through pipes 302 and telescoped by pressure applied through pipes 402. The edges of the base and roof plates 2, 3 are chamfered to facilitate sliding movement and the props may engage the roof plate through ball and socket connections. A guide rail for a scraper box may be attached to the base plates 2 of alternate supports B, D as shown in Fig: 1. The guide rail is formed in sections 20, 21 interconnected by links 22. The links are each pivotally connected to the associated base plates through a resiliently mounted slider 24. Pressure is applied to the props 1 of supports A, C, E through pipes 101, from which connections 102 are taken to junctions 104 through valves 103 and feeders 105. The props of supports B, D are similarly supplied through pipes 201, 202, valves 203, junctions 204 and feeders 205. The pressure in the pipes 101, 201 and in pipes 301, 401 feeding the rams 5 is controlled by a device which may be some distance away from the support. Instead of being arranged at an angle as in Fig. 1, the rams may be disposed parallel to the line of movement, i.e. at right angles to the line of the guide rail. In a form described only in the Provisional Specification the triangular plates are not used (see Fig. 3), the supports comprising single props 7, 8, 11, 12, 13 interconnected by rams 9, 10. The guide rail sections 14, 15 are connected to the props by resilient buffers 16, e.g. of rubber.