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.

A wood screw, including a cylindrical screw shank, at the end of which there is formed a tip, a screw head, which is formed at the other end of the screw shank, as well as a threaded section, which extends from the tip in the direction of the screw head, wherein the threaded section has a thread core and a thread winding having several threaded turns circulating the thread core, wherein several successive threaded turns have projections, which are formed alternatingly in essentially the direction of the screw head and in essentially the direction of the tip.

This present invention relates to a dual head screw that features at least one male nut driver extending outwardly from a base head opposite the shaft of the screw. The dual head screw replaces standard female head screws, thus eliminating concern over stripping of the screw head or the same becoming compacted with debris. The dual head screw has a shaft with a threaded section, a base head and the male nut driver. The male nut driver is dimensioned in size to withstand the torsional forces associated with installing or extracting the dual head screw from an object, and may be driven or extracted with a standard hand tool or a power drill. In a further embodiment, the male nut driver may be comprised of a first driving portion and a second driving portion.

A device for removably connecting a lining layer to an inner shock-absorbing portion of a helmet, mainly made of foam is disclosed. The device includes a first element constrainable to the lining layer and a second element constrainable to the inner shock-absorbing portion. The second element has a threaded portion that can be inserted by screwing it in the foam of the inner shock-absorbing portion. The device also includes means for the mechanical snap-fit coupling between the first and the second element.

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).

The invention is an expanding, anchoring screw, made of expandable polymer material. The screw shaft is hollow. After inserting screw in a material, by allowing two reagents to mix in the hollow shaft, and a polymerization chemical reaction to occur, the reagents increase in volume exerting pressure against the inner surface of the hollow shaft, expanding the shaft, and applying greater anchoring force against material in which the screw is inserted.

An anti-pullout and low-resistance screw includes a shank, a screw-in portion, a head portion, and a thread. The thread is helically formed around both the screw-in portion and the shank and includes a plurality of thread convolutions. Each thread convolution includes an upper tooth surface facing the head portion and a lower tooth surface facing the screw-in portion. At least one tapered pressing structure is designed on the screw-in portion and/or the shank to define at least one section with its outer diameter tapering towards the screw-in portion gradually. The tapered pressing structure extends from a bottom edge of the lower tooth surface along a longitudinal axis of the shank. The lower tooth surface has a lower tooth surface height that is greater than the thread height. An annular anti-pullout plane is formed on the shank between two adjacent thread convolutions to enhance the anti-pullout strength of the screw

A self-tapping screw includes a screw head, a screw shank having a shank body extending from the screw head along an axis, a self-tapping thread extending helically around an outer peripheral surface of the shank body and having a plurality of cutting edges continuously connected to one another and extending outwardly, radially and taperingly from the outer peripheral surface of the shank body, and a supporting unit including a plurality of supporting teeth each disposed between two adjacent ones of the cutting edges, and a plurality of concave surfaces respectively adjacent to the supporting teeth and extending inwardly from the outer peripheral surface of the shank body.

The invention provides a low-wear screw structure which comprises a screw head, a rod body, a first thread and at least a crushing rib, wherein the rod body extending out from the screw head and being successively formed with a rod extension part, a reaming part and a taper part, the first thread being annularly arranged on an outer peripheral surface of the rod body at a distance from the taper part to the rod extension part through the reaming part, the crushing ribs being arranged on the rod body at the reaming part, wherein a first included angle is formed between the first side surface and the outer peripheral surface of the rod body, a second included angle is formed between the second side surface and the outer peripheral surface of the rod body, and the first included angle is different from the second included angle.

A removable stud, tool for inserting and removing the stud and kits comprising the studs and tool are provided. The removable stud comprises a hexagonal head portion connected to a threaded pointed shank portion. The hexagonal head portion includes a notched flange portion that has two diametrically opposed notches that are each centered on a vertex of the hexagonal head. The tool includes a wrench head comprising a neck with two substantially diametrically opposed walls extended therefrom. Each wall has an interior face configured to receive a vertex of the hexagonal head of the stud and a tip portion configured for the notch of the stud.