GB831275A - Walking support systems for mine roofs - Google Patents

Abstract

831,275. Mine roof supports. GEWERKSCHAFT EISENHUTTE WESTFALIA. May 2. 1956 [May 27, 1955], No. 13575/56. Class 20(2) Pit props engaged with the mine floor and roof 'by springs or hydraulic pressure through foot and head pieces 16, 17, Fig. 1 also engage the floor and roof by means of plates 22, 30 at the foot arid head of the pit prop respectively, which are subjected to a force greater than the springs or hydraulic pressure and which is directed obliquely to the length of the prop so as to advance it towards the coal face. This force is supplied by hydraulic pressure acting in cylinders 19 on pistons 20 and inclined piston rods 21 connected to the plates 22, 30. The prop is moved forward until it is stopped by engagement with the plate 22 of the side of the recess 23, in which the plate 22 is constrained, and when the pressure in the cylinder 19 is relieved a spring 24 returns the plate 22 for another move. The prop 10 is hydraulic and engages cylinders 19 by universal joints 15. The pistons 20, rods 21 and plates. 22 may be pivotable about the longitudinal axis of the prop to vary the direction of advance. In Fig. 2 the prop has fork-shaped foot and head members 35, 36 engaging pairs of floor and roof bars 37 between which the prop engages the floor and roof by means of plates 53 adapted to be acted' on by pistons and cylinders 51 con-- nected by knife edge bearings 49 with the prop and plates 53 and arranged obliquely to the longitudinal axis of the prop. The movement of the props is limited by crossbeams 55 on the roof girders. The plates 53 and bars 37 are connected by rails 54 with a second prop. In ordter to allow relative movement between the upper and the lower parts of the prop the main cylinder 41 is arranged under a cylinder 43 which it engages by a rim 42 and the head member 36 engages over the cylinder 43 which it engages by a rim 45. In the second prop the lower fork also engages the cylinder 43 by a rim. The prop may be engaged with the roof and floor by a spring 48 or hydraulic pressure in the cylinder 41. One end of a prop may alternatively be advanced by a caterpillar track.