Patent GB-760630-A (GB)
Title: Improvements relating to link linings for roof and wall supporting purposes in mines
IPC: E21D11/15
Filed: 1954-05-25
Abstract: 760,630 Mine roof supports. LOBBERT & CO., GES. May 25, 1954 [Nov. 5, 1953; Feb. 5, 1954; Feb. 10, 1954], No. 15421/54. Class 20 (2) Wire links bridging the distance between supports for the roof of a tunnel so as to provide a lining against the ceiling of the tunnel, are connected together by means of hooks formed at one end, in a chain in the direction of advance of the support system and are each anchored to the support adjacent the hooked end by an attachment member which has eyes or the like to be slipped over the hooks and means for engaging the supports.. As shown in Figs. 1 and 2 the wire links 2 are U-shaped having parallel limbs each formed with a turned back portion 3 forming a hook. A succession of links is built up by connecting the first one to the support by means of an S- shaped double hook and connecting succeeding ones together by engaging the bridge part of each link with the hooks 3 of the preceding one. To avoid excessive tension developing along the length of the succession of links, the hooked ends are attached to the supports by wire members 4, which as shown, engage the hooks by eyes 6 and engage the flange of the support by the arms 4a, 4b which are bent over to make a permanent attachment. The arms may be bent over by a tool which consists of a claw 19 to engage over the other flange of the support and a lever 9 carrying a cross-member 11 adapted to bear on the arms 4a, 4b as the lever is pulled down (to the dotted position) and bend them into engagement with the lower face. Guide bosses 10 on the pivot pin of the lever bear down on the arms as they are bent. The eyes 6 lie in a plane raised somewhat about the surface of the support so that the arms 4a, 4b are allowed to lie flat against the support. The bridge piece of the next wire link is inserted into the hooks over the eyes 6. Instead being of wire the attachment member may be made of sheet metal, as shown in Fig. 4. The eyes are formed by holes 8 in side lugs 8a which are upwardly bent so as to lie above the plane of the bearing 7. The end of this portion is bent into place as before. Where the support members are wooden poles, the attachment members are. bent to engage the curved surface thereof and are secured in place by a nail or spike driven into the' pole. As shown in Figs. 5 and 6 attachment members 4 for this purpose may be of wire and formed with eyes 6 at one end and coincident 'eyes or loops 12 at the other, through which, the nail is driven. Alternatively the arms of the attachment member may be sharpened and formed as spikes to be driven into the pole, or the arms may be twisted together and the nail placed in the angle so formed. Instead of being made of wire the attachment member may be made of triangular metal plate having holes at the corners and curved to fit the pole. To avoid excessive tensions being set up the length of the chain of links may be limited by connecting the last link to the support and starting a new chain in a line offset from the previous one. Where the wire links are shorter than the distance between supports compensating members may be inserted to make up the length. These compensating members are wire links similar in form to the main links 2. The limbs of the links are connected together by bracing wires 26.