GB1008863A - Anchoring device, particularly for roof bolts in underground galleries - Google Patents

Abstract

1,008,863. Anchor-bolts; screw-sockets. SOC. ANON. DES FORGES & BOULONNERIES HERMANT-HICGUET ET D'ARS-SUR-MOSELLE. April 12, 1962 [April 13, 1961; July 25, 1961; March 28, 1962], No. 14252/62. Heading F2H. Each shell 1, 1<SP>1</SP>, Fig. 6, of the expansible anchorsleeve, e.g. of a mine roof bolt, has at least one ramp 5, 5<SP>1</SP> for co-operation with a sloping face of a wedge, formed at the end of the shank 8 or on a nut threaded on the shank end, and also has a cavity 13, 13<SP>1</SP> separated from the ramp 5, 5<SP>1</SP> by a shoulder 14, 14<SP>1</SP> on which the shell 1, 1<SP>1</SP> rocks on the wedge face in the position of final expansion (when the bolt shank 8 is drawn out of the bolt hole to its extreme location) so that the shell is spread in the form of a V as shown in Fig. 6. There may be further steeper shell-ramps 7, 7<SP>1</SP> so that a lug 11, at the top of each of the two parallel sides of the flat wedge between the sloping faces, bears on both the ramps 7, 7<SP>1</SP> to give the wide spread at the tops of the shells. In the form shown in Fig. 7, there is a single convex ramp 24 in each shell for co-operation with a concave face, Figs. 8, 9 (not shown), and the lugs 32, 32<SP>1</SP> of the wedge 31. The shells may be interconnected by spring leaves 3, Fig. 6, and these may be crossed, Fig. 1 (not shown), or side-by-side as are the leaves 23, 23<SP>1</SP> in Fig. 7. The leaves tend to hold the shells apart for the pre-anchoring of the bolt which may be facilitated by mounting a rubber ring on the sleeve. In place of the leaves a stop-plate may be fitted on the rod to prevent axial movement of the sleeve shells on insertion in the bore hole. The shells may be kept in position by an elastic band and have lugs to prevent their relative axial movement. In another form, Fig. 10, with convex ramps 37, 38, and corresponding concave faces on the wedge 47, the parallel faces of the wedge are rebated towards the free end but, at the end, a lug 55 extends from each face thus inset and holds, on that face, one of a pair of resilient pads 53 of rubber or spongy synthetic material when the bolt is in the condition shown, ready for insertion. Inturned lips 43, 44 at the end of the shells 35, 36, each with a slot 45, 46 at its middle to allow the rebated wedge-end to pass through, retain the pads 53 when the wedge 47 and shank 48 are displaced upwardly, Fig. 11 (not shown), compressing the pads, when the sleeve is impeded by a narrowing of the bore and the shells are tightened together. The sleeve is returned to the position shown by the resilience of the pads when the narrowing is passed. The shells are held together, at least temporarily, by a rubber band. Stop-ribs 49, 50 on the shank 48 move up into slots 41, 42 in the ramps 37, 38, when the shank moves up in the sleeve, to abut on shoulders 39, 40.