GB541395A - Improvements in or relating to wedge block supports particularly for use in coal andlike mines - Google Patents

Abstract

541,395. Wedge chocks for mines. HEWITT, T. H. Sept. 5, 1940, No. 13893. [Class 20 (ii) ] A wedge chock for use in mines either alone or with mine props comprises upper and lower members 1, 4 with parallel outer faces and inclined inner faces and a central wedge member 9, the upper and lower members being constrained by means of interfitting projections and grooves for vertical sliding movement only and the wedge serving to lock the members of the chock. In one form as shown in Fig. 2, the wedge is hollow and encloses interengaging projections 5 from the upper and lower members, these projections having inter-fitting lug and groove connection, 7 and 8, so that they can move only vertically with respect to each other. These projections are further provided with lugs 13 which engage inclined recesses in the hollow of the wedge whereby the parts are retained in assembled position. A link 16 acts as a stop to. prevent disengagement of the parts. In another form as shown in Fig. 10. the inter-engaging projections and grooves, 21 and 22 respectively, on the upper and lower members 18, 19 lie outside the intermediate wedge member 25 and lugs 24 on these members engage grooves in the side of the intermediate member whereby they are retained in assembled position. The grooves 22 may be closed at their outer ends. The chock may be attached to the end of a pit prop 31 by a pivot bolt 32 on one side and a locking pin 33 on the opposite side as shown in Fig. 15.