A fastener includes a shank having a first end and a second end defining a length. The fastener includes a thread provided on the shank, the thread including a first region adjacent to the first end and a second region between the first region and a head at the second end, the thread includes a leading edge and a trailing edge, each edge forming an angle with a surface of the shank, the leading edge forming a non-normal angle with the surface of the shank and the trailing edge forming an angle about normal to the surface of the shank. The fastener may include an arcuate detent region in the shank between respective turns of the thread, the detent region having a length, the length decreasing from the first end toward the second end between the respective turns. The fastener may include a plurality of flutes positioned along a length of the shank.

A self-drilling, anti-burr, threaded fastener is provided having at least two different thread portions. The first thread portion extends along the tip and the second thread portion extends along the tapered portion adjacent to the tip. A third thread portion can be provided between the first and second thread portions that includes a plurality of axial gaps that extend to the thread root to remove burrs. Alternatively, knurling is provided in an area where the first and second thread portions meet, and the knurling acts to remove burrs.

A screw element is disclosed having a shaft with an outside screw thread and a longitudinal axis extending along the shaft and thereby defining a distal direction and a proximal direction, and an insertion direction and an opposite removal direction, and has a tool attachment point starting radially inwards and the tool attachment point has a central opening and in the wall of this opening at least five tooth profiles directed radially outwards and mainly parallel to the screw axis directed radially outwards and mainly parallel to the screw axis are formed in the wall of this opening, and for each tooth profile an insertion wall in insertion direction and a removal wall in removal direction can be separated, characterized in that the surface of the insertion wall is greater than the surface of the removal wall.

A fastener for attaching structures to a tree employs, in an embodiment, a hanger bolt, a protective collet, and a mounting bracket for attaching a support structure to a tree in a way that minimizes damage to the tree. In some embodiments, an extending member adds length to the bolt. The mounting bracket attaches to the bolt. The bracket serves to affix hardware and separate support structures to a tree.

A screw having a shank, wherein the shank has a tip end and a rear end, and a screw thread, which is connected to the shank, and which winds around the shank, wherein a wedge groove is provided in the shank, which wedge groove winds around the shank and extends alongside at least a section of the screw thread, wherein the wedge groove is delimited by a rearwardly tapered wedge flank for wedging a grout shell surrounding the shank, characterized in that the shank has a buffer zone, which extends alongside the wedge flank and alongside the screw thread, and which adjoins the wedge flank and which adjoins the screw thread, wherein the rearward taper of the wedge flank is larger than the rearward taper of the buffer zone.

A screw having a screw head and a screw shank, wherein the screw head is provided with a driving formation and the screw shank is provided at least partially with a thread. The screw shank has a cylindrical holding portion and an end portion that narrows towards a screw end, and in the holding portion the thread is formed as a standard thread. The holding portion has a circular cross section, and the end portion narrows starting from the holding portion. The end portion is provided with at least two thread turns which are formed as a forming thread, and the end portion has a polylobular cross section and the screw shank is hardened in the holding portion and in the end portion.

A screw having a shank, wherein the shank has a tip end, a rear end, and a longitudinal axis extending through the tip end and through the rear end, wherein the tip end and the rear end are opposite ends of the shank, and a screw thread, which is connected to the shank, and which winds around the shank, wherein a wedge groove is provided in the shank, which wedge groove winds around the shank and extends alongside at least a section of the screw thread, wherein the wedge groove is delimited by a rearwardly tapered wedge flank for wedging a grout shell surrounding the shank. The screw thread extends further towards the rear end of the shank than does the wedge groove.

A screw having a shank, wherein the shank has a tip end, a rear end, and a longitudinal axis extending through the tip end and through the rear end, wherein the tip end and the rear end are opposite ends of the shank, and a screw thread, which is connected to the shank, and which winds around the shank, wherein a wedge groove is provided in the shank, which wedge groove winds around the shank and extends alongside at least a section of the screw thread, wherein the wedge groove is delimited by a rearwardly tapered wedge flank for wedging a grout shell surrounding the shank. At least one ridge is provided within the wedge groove, wherein the ridge compartmentalizes the wedge groove.

The present invention provides a fast chip removal reaming screw, including a screw head, a rod body extending from the screw head and a first thread arranged on the rod body. The rod body includes a rod body portion connected to the screw head, an reaming portion, and a pointed cone portion. The reaming portion includes first reaming blocks, second reaming blocks and third reaming blocks which are disposed in a helically staggered manner, and chip removal paths formed between the first reaming blocks, the second reaming blocks and the third reaming blocks. A first width of the chip removal path located between the first reaming blocks and a second width of the chip removal path located between the second reaming blocks are different, so that wood chips can be fast removed to reduce a stress between the screw and a wood workpiece.

The present invention relates to a screw element (1) comprising a threaded shaft (2), a screw tip (4) formed on one shaft end and a screw head (5), formed on an opposite shaft end and with force application means (7), and comprising a screw thread (12) extending on the threaded shaft (2) and on the screw tip (4), wherein the screw tip (4) has a front tip section (4a) tapering toward the screw element end, when viewed in the screwing-in direction (Z), and a section (4b) formed on the threaded shaft with a polygonal cross section, when viewed in cross section, whose enveloping circle diameter (d.sub.h) is greater than a core diameter (d.sub.k) of the screw tip (4), and the polygonal cross section has a corner point (15) lying on the enveloping circle of the section (4b), and a front edge surface (9), radially oriented with respect to a longitudinal center axis (X-X), ends in said corner point in the sense of an increased diameter. The screw tip (4) has a first tapering tip section (4a) with a circular cross section and a second, cylindrical tip section (4c) with a circular cross section formed between the first tip section (4a) and the polygonal section (4b), wherein the screw thread (12) is continuously formed without interruption across the first and second tip sections (4a, 4c) of the screw tip (4).