A screw fastener comprising: an elongate shank (3) having a screw thread (9) extending along at least a substantial portion of the shank; a drive section (7) located at one end of the shank for allowing the screw fastener to be rotatably driven into one or more material layers; and a self-drilling or piercing point (5) at an opposing end thereof for forming a bore in said one or more material layers; wherein the drive section is shaped to minimise or avoid the need for countersinking of the formed bore.

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 wood screw includes a head, a shank axially extending from the head, a main thread extending helically around the shank in a tightening direction and having an outer diameter ranging from 3 to 16 mm, and a plurality of forward ribs extending spirally around the shank in a same direction as the main thread. The number of the forward ribs ranges from three to five. Each forward rib, in a cross section thereof, has a first outer edge facing the tightening direction, and a second outer edge facing opposite the tightening direction and having a length shorter than that of the first outer edge. Each forward rib has a height smaller than that of the main thread, and a lead angle greater than that of the main thread.

A screw has a screw head and a shank extending downwardly from the screw head. The shank has a threaded segment, a cutting segment, and a tapered segment sequentially arranged downwardly, a thread spirally surrounding an external surface of the shank from the threaded segment to the tapered segment, multiple cutting ribs arranged around the external surface of the shank on the cutting segment of the shank, and multiple chip recesses formed between the cutting ribs. Each of the cutting ribs has a rounded crest to enlarge a drill hole and to reduce a resistance formed between the cutting ribs and the workpiece during drilling. The screw can be easily screwed into the workpiece with less driving force.

A fastener has a head and a shank extending from the head to a tip. The shank has a threaded distal portion that includes primary threads defining a major diameter, a minor diameter, and at least one helical rib or scalloped surface at the minor diameter. The at least one rib extends between adjacent primary threads of the threaded portion and extends in a helical configuration. The configuration of the fastener with helical ribs in the minor diameter reduces contact surface area between the fastener and building material substrate, like wood, during installation of the fastener, which thereby results in less torquing force required for installation.

A structural screw usable in multiple different substrates/materials includes a head end, a shank and a tapered end, the head end including a tool engaging part, the head end located at a first end of the shank and the tapered end located at a second end of the shank. A thread is formed along the shank, wherein the thread begins on the tapered end, extends onto the shank and terminates at a first axial location along the shank that is spaced from the head end. The thread (i) is a multiple start thread formed by at least a first helical thread and a second helical thread and/or (ii) includes a thread angle of between fifteen degrees and thirty degrees. The screw may also include a reaming section with leading and trailing wedge sections and/or an asymmetric notch pattern along at least part of the thread edge.

A screw for particle board includes a head; a threaded shank; and a plurality of screw threads formed on the threaded shank. The head includes a slot on a top. The threaded shank is formed with the head and includes a shank and a tip at an end of the shank. The screw threads are formed on both the shank and the tip. The shank includes a plurality of longitudinal recesses and a plurality of longitudinal projections. Each recess is adjacent to each projection. Each screw thread is disposed between one of the recesses and the projection adjacent to the recess.

A fastener unit and related method for securing a board to a support is provided. The fastener unit includes a spacer block, a grip element extending from the spacer block and configured to fit in and engage a groove of the board, and one or more board engagement elements extending from a portion of the spacer block. The board engagement elements can clamp the board, between an upper and/or lower surface of the board and a groove of the board, thereby securing the spacer block in a position adjacent the groove to establish a gap between the board and another board. Related methods of use also are provided.

A screw and method for the mounting of boards/planks, in particular fiber cement planks, on a support of wood. The screw comprises milling wings and a first thread between the milling wings and the tip, and a second, larger thread with smaller pitch between the milling wings and the screw head.

The invention relates to a connecting device (3) for mounting a wooden construction element (1), in particular in the form of a panel or beam, on a support (2a), wherein the connecting device (3) has a mounting node (4), which is designed for mounting the connecting device (3) on the support (2a), and a coupling arrangement (5), which is connected to the mounting node (4) and which, in the installed state, while projecting from the mounting node (4) on an upper side (1a) of the wooden construction element (1) can be connected to the latter by fastening members (7), which at least partially pass through the wooden construction element (1), wherein the mounting node (4) and the coupling arrangement (5) are each produced from a material which has a higher strength than that of the wooden construction element (1). The invention further relates to a wooden construction arrangement having a connecting device (3) according to the invention and to a structure having such a wooden construction arrangement.