Abstract: A self-expanding and self-undercutting guard rail bolt includes a dowel having a guard rail fastening end and a ring. The fastening end is configured to be driven in rotation, and the ring is configured to rigidly connect to a first screwing end of the dowel by an incipient fracture portion. The self-expanding and self-undercutting guard rail bolt further includes a counter-dowel screwed to the dowel by a second screwing end. The counter-dowel includes an expansion cone, and an anti-rotation head having at least one edge which projects beyond a periphery of the dowel to prevent rotation of the counter-dowel about an axis of the guard rail bolt.

Abstract: This invention provides a fastener (20) that is adapted to be mounted in a hole provided in a wall (not shown). The improved fastener comprises: an elongated tubular body (21) having a first end (23) and a second end (24), having an outwardly-extending flange (25) adjacent the first end, having an intermediate portion (27), and having a distal marginal end portion (37) adjacent the second end, the body also having an abutment surface (32) facing toward the second end; and a member (22) adapted to be inserted into the body through the second end, the member having an abutment surface (40) adapted to bear against the body abutment surface, and having an outer polygonal surface (41); and wherein the body marginal end portion (37) is adapted to be plastically deformed about the member to hold the member within the body.

Abstract: A joining assembly for joining a pair of structural members, comprises a bolt having a thread and a nut-like blind rivet adapted to be inserted into mounting holes of the structural members and to be threadingly engaged to each other. One of the mounting holes is made of resiliently deformable material and comprises a base member including a bore for receiving the thread of the bolt and having an outside provided with a plurality of threads which are similar in number to the corners of the polygonal mounting hole, such that when the bolt is threadingly engaged into the bore of the blind rivet the base member is folded whereby the threads have parts of their flanks pressed against one of the structural members.

Abstract: A spreading anchor (1) including an anchor rod (2) provided at its front end, when viewed in a setting direction, with a head (3, 30) having at least several regions, which taper outwardly in the setting direction, and extending through an axial through-bore of an expansion sleeve(5) axially displaceable along the anchor rod (2, 20) and having a plurality of axial longitudinal slots (7) extending from a front end of the expansion sleeve (2, 20) and forming at least two, located opposite each other expansion tabs (6) provided at their free front ends with cutters (16), the spreading anchor (1) being supported against an upper surface of a ground (G) and further including rotation-transmitting driver elements for transmitting axial rotation, which is generated during setting of the anchor rod (2, 20), to the expansion sleeve (5).

Abstract: Anchor assembly for a mine roof bolt or the like in which the bail of an anchor shell having leaves for engaging the side wall of a bore hole has spring fingers for snagging the side wall of a bore hole to prevent downward movement to the anchor shell. The bail has a central opening for the roof bolt to pass through with the central opening having projections that extend inwardly of the opening to form an interference fit with the threads of the bolt as it is rotated through the opening. The leaves of the anchor shell which are clamped against the side wall have surfaces which diverge from tapered surfaces of the plug nut for expanding the anchor shell to prevent plowing between the plug nut and anchor leaves. The surfaces on the leaves extend downwardly from the top to about the bottom of the leaves.