Abstract: A delay stopper for use in a mine roof anchor is provided. A mine roof anchor has a threaded roof bolt and a threaded receiving member for the roof bolt whereby the roof bolt and the receiving member initially rotate as a unit to mix resin components that are placed in the bore hole in a destructible capsule above the roof anchor. When the roof anchor is placed in the bore hole, the destructible capsule is ruptured, and the components within the capsule are mixed to form resin which at least partially secures the mine roof anchor within the bore hole. The delay stopper causes the roof bolt and the threaded receiving member to rotate as a unit to mix the resin after the capsule ruptures. The delay stopper has a cylindrical body portion interfitting into the threads of the threaded receiving member and a conical end portion formed on the cylindrical body portion and extending axially from the body portion in a direction toward the end of the roof bolt. The delay stopper is preferably formed of an epoxy resin.

Abstract: A system is disclosed for anchoring a tensioned bolt in a drill hole in the roof of a mine, or other such location. The bolt is threaded from one end and has a head on the other end which carries a standard bearing plate. The bolt passes through a hollow tube having an outer diameter slightly (e.g., 1/8") smaller than the bore hole diameter. The threaded end of the bolt engages a nut affixed to the upper end of the tube and extends through the nut to the end of the threads. A standard, mechanical, expansion anchor is carried on the threaded end of the bolt extending through the tube and is inserted into the drill hole behind a conventional, two-compartment resin package. As the bolt is pushed into the hole, the package is broken and the resin components are forced into the annular space around the hollow tube, as well as around the threaded end of the bolt and expansion shell.

Abstract: A truss system is disclosed for use in supporting the roof of a mine. The system comprises an assemblage of elements which permit more rapid and efficient installation than prior art truss systems which have generally been installed as a secondary operation, after the standard, required bolting pattern is in place. The present system, on the other hand, may be installed concurrently with and in fact may become part of, the standard bolting system. The system includes a pair of roof bolts installed in conventional fashion in drill holes extending at divergent angles into the mine roof on opposite sides of the mine opening. The bolts each extend through aligned openings in a bearing support plate and a separate angle block having a curved outer surface. The closed ends of a U-bolt, having a curvature corresponding to the surface of the angle block, extend around the two blocks with the open, threaded ends of the U-bolts facing one another.