Abstract: An anchoring plug made from a hard-elastic plastic material having a closed shank part 1 and two mutually opposite spreading fingers 2 and 3. A screw hole 10, extends through the shank part 1 down into a central space 12 between the spreading fingers for receipt of a screw 18. To be able to drive the plug directly into gypsum board without having to first drill a hole, one spreading finger 2 is longer than the other spreading finger and has a hook-shaped tip 4 forming a recess 5 at its free end. Initially the end of the shorter spreading finger 3 nests in this recess to provide a pointed end to the plug, but springs free of the recess when a screw is screwed into the plug.

Abstract: A threaded insert for drywall with a structure comprises a cylindrical body which includes an axial entrance hole at one end, an axial cavity at the other end, a high auger disposed thereon, a low thread disposed between the auger, a pair of drilling bits, diametrically opposed to each other, attaching to the bottom periphery of the axial cavity and extending therefrom to terminate a separately attached drilling tip. Extending from the entrance hole through the cavity, the body includes an internal passage for the insertion of a threaded fastener and facilitating the expelling of dusts. The drilling tip are separable upon the advancement of the fastener driven through the internal passage. The low thread strengthens pull-out resistance while the insert installed in the wall.

Abstract: A vibration-resistant two-member fastening device characterized by quick lock and release. The first of the two members has an engagement edge which is adaptable to apply pressure on the second member. The second member has either a recessed surface or a threadline, the diameter of which decreases from a front point away from the head towards a back point close to the head.

Abstract: A self-drilling plastic anchor installable in a wall by means of a screwdriver, the anchor being adapted to receive a threaded fastener that serves to hold a fixture or other object against the wall. The anchor includes an externally-threaded shank section having an enlarged head that is engageable by the screwdriver and a cavity to receive the fastener. Extending from the lower end of the shank section is a drill section that terminates in a point that lies on the longitudinal axis of the anchor. When the anchor is applied to the wall, the point penetrates its surface, so that the anchor may then be turned by the screwdriver about the point. The drill section is formed by a pair of cutting blades on opposite sides of the anchor axis and a pair of guide blades, each angled relative to a respective cutting blade.

Abstract: Disclosed is an anchor assembly especially for use in a plastic wall-panel which comprises a plug formed of a forward section comprising a tapering plastic board-piercing part and an integral ram head, and of a hollow cylindrical section pivotably connected to the forward section. The assembly may further comprise a spike capable of being driven into the hollow cylindrical section, the spike being provided with a cylindrical portion having serrations on its outer surface for bitting into the cylindrical section or ram head and thus being secured to this section or head. The spike is provided with a hammer portion having a length sufficient at least to engage the ram head, as it is driven into the plug, and to cause pivotal of the forward section of the plug and abutment thereof against the concealed side of the plaster-wall panel.

Abstract: A fastening element assembly for use in a hard receiving material, such as concrete, masonry and the like, includes a sleeve and a fastening element or bolt. The sleeve forms a blind bore in the receiving material. At its leading end, in the insertion direction, the sleeve has a cutting edge. The sleeve is rotated by rotational force transmitted to engagement faces on the sleeve. After the borehole is drilled by the sleeve, the bolt is driven through the sleeve into the receiving material.

Abstract: An expansion dowel assembly is made up of an anchor bolt and an expansion sleeve laterally enclosing the bolt. The sleeve is expanded by driving it in the axial direction relative to the bolt so that the end of the sleeve widens as it moves axially over a conically shaped expanding member on the bolt. The axially extending surface of the expanding member is formed as a concave surface affording an increasing conicity in the driving direction. Cutting teeth are formed on the outer surface of the sleeve and provide a saw-tooth section. When the sleeve is driven relative to the bolt, the teeth cut into the surface of a borehole in a receiving material and form an undercut in the borehole surface. To facilitate expansion, an annular groove is located in the outside surface of the sleeve adjacent the cutting teeth. The annular groove is located on the opposite side of the cutting teeth from the leading end of the expansion sleeve.

Abstract: An expansion dowel assembly is made up of an anchor bolt and an expansion sleeve laterally enclosing the bolt. The sleeve is expanded by driving it in the axial direction relative to the bolt so that the leading end of the sleeve widens as it moves axially over a conically shaped expanding member at the leading end of the bolt. Cutting teeth are formed on the outer surface of the sleeve at its leading end and provide a saw-tooth section. The teeth cut into the surface of a borehole in a receiving material and form an undercut in the borehole surface as the sleeve is expanded. To facilitate expansion, an annular groove is located in the inside surface of and adjoining the cutting teeth. The annular groove is spaced on the opposite side of the cutting teeth from the leading end of the expansion sleeve.

Abstract: A drive-in expansion fastener is provided having a generally cylindrical, hollow body with a tapered end formed from an angular truncation of the body. The body is reinforced by at least one longitudinal rib so as to permit drive-in penetration from the tapered end even if the fastener is formed from plastic materials. The fastener is retained within the wall by at least one pair of hinged flanges which expand circumferentially in response to the threaded insertion of an ordinary screw within the hollow portion of the body. That screw engages an inclined surface within the body to cam the flanges outwardly. The flanges engage the back surface of the wall while a longitudinally slit portion of the body expands within the hole created by drive-in penetration.

Abstract: An anchor dowel assembly includes an axially elongated sleeve with window-like openings extending through its wall transversely of the axial direction. Locking members are positionable within the window-like openings for displacement radially outwardly from the sleeve for effecting the anchoring action. The locking members are displaced radially outwardly by an expansion tool driven between the locking members by a force directed in the axial direction of the sleeves.

Abstract: An anchoring bolt (1), which can produce a conical undercut by rotation in a cylindrical hole and serves simultaneously as a securing element has a connection portion (2), a shaft (4) and an insertion portion (5). The insertion portion (5) has an axially extending slot (6) forming two spreadable branches (8,9), into which slot a movable spreading wedge (18) can be driven in with its tapered end. The branches (8, 9) are each provided with drillings (14, 15) receiving hard metal pins (16, 17) of which the front edges, in the rotation direction, are more protuberant than the rear edges so as to form a clearance angle .alpha..

Abstract: In order to produce conical undercutting of the bore when the anchoring bolt is driven into a previously bored hole with a percussion drill, the insertion end of the bolt has a slot into which the thin end of a wedge is inserted. Hard metal pegs set in radial bores near the insertion end of the bolt at diametrically opposite places on the periphery of the bolt protrude slightly and, as the bolt is driven into place, the wedge spreads its insertion end and causes the hard metal pegs to undercut the walls of the bore more and more as the bolt is set in place. A conical undercutting of the bar thus results.

Abstract: A fastener useful for securing articles on a hollow wall, made of a thin sheet of metal, shaped as to provide two spreadable pointed thin blades for easy insertion into a wall where after the blades are spread apart by the insertion of a screw to form an anchor resisting withdrawal.

Abstract: A unitary hollow plastic screw anchor which is capable of being hammered or otherwise driven into a hollow wall, with a weakened separation plane adjacent the entrance portion which is sufficiently strong to hold together during installation in the wall, and sufficiently weak to split apart when a screw is inserted into the installed anchor. Features of the anchor include a generally cross-shaped entrance end for minimal penetration resistance, a generally rectangular interior with arcuate screw centering grooves, a single turn helix adjacent the wall-engaging flange thereof to start the screw, an internal step configuration to accommodate screws of varying diameter, and two longitudinal slots which compress during installation to further reduce penetration resistance.

Abstract: A self drilling, closed end, blind rivet has a hexagonally shaped flange, or other suitably shaped means of driving, at one end and a hardened drill bit at the other end, with the two being joined by an integral sleeve wall with a rolled groove in it that forms an internal chamber to retain the head of a mandrel. Withdrawal load on the mandrel, after the rivet has been inserted through a hole drilled by it in a plurality of layers to be joined, will upset the sleeve wall into a folded flange that coacts with the hex head, or other driving means, to tightly grip the outside face and the blind face of the layers being joined.