Abstract:
The invention relates to a thread-forming screw (10). Said screw (10) has three or more, preferably three thread turns (20, 22, 24) which are embodied parallel to each other and which extend in a helical manner at least over part of the length of the shaft (16). At least two of the thread turns (20, 22, 24) have a different outer diameter (d1, d2, d3). Said thread-forming screw is characterised in that the outer diameter (d1) of a first thread turn (20) is greater than the outer diameter (d2, d3) of the respective second and third thread turns (22, 24) counter to the setting direction of the first thread turn (20).
Abstract:
A self-countersinking, self-tapping screw has a head with a substantially flat underside that acts like a washer for bearing against a surface of a material into which the screw is inserted. On an underside of the head are one or more material-receiving pockets. These pockets receive material when the head of the screw bears against the surface. These pockets thus help lock the screw in place, i.e. help to prevent the screw from loosening over time. These pockets may have a circular or non-circular shape.
Abstract:
Eine Gewinde formende Schraube zum Verspannen zweier Bauteile zeichnet sich dadurch aus, dass die Schraube zwei Gewindeabschnitte (4, 5) mit Gewinden unterschiedlicher Ganghöhen aufweist, wobei die Gewindegänge der beiden Gewinde im Stoß aneinander anschließen.
Abstract:
A self-countersinking fastener for engagement with wood or similar composite material, said fastener including a penetrating shaft, and a tool engaging head; wherein said tool engaging head is substantially frusto-conical in overall shape and provided with one or more indent regions into which said material may be pushed as the head is turned; wherein each of said indent regions include: a trench extending substantially vertically through the entirety of said head; and a tailing section extending through the entire height of the head and extending forward in the direction of turning from said trench such that the radius of the head in the corresponding section increases throughout said section..
Abstract:
A thread forming screw thread fastener for fastening into a hole formed by the fastener in a work piece, the fastener comprising: a head having a drive to be engaged with a driver bit; and a shank with threads having a symmetrical thread profile with a minor diameter and a major diameter, the major diameter defining a thread crest of the screw thread, and the minor diameter defining the thread root of the screw thread, the profile of the screw thread defined by the surface of the screw thread between adjacent thread crests forming a thread flank, the thread flank having a first central portion of constant radius along the thread root, the radius common at the thread root, at each adjacent thread crests, and at two transition intersection points, the profile of the thread flank having second and third portions defined by surfaces having different radii of curvature between each transition intersection point and each adjacent thread crest.
Abstract:
Eine Holz- und Kunststoffschraube, mit einem Kopf (2), einem im wesentlichen zylindrischen Schaft (4, 6, 8), einer Spitze und einem sich über den Schaft (8) bis in den Spitzenbereich (10) erstreckenden Gewinde (14), das eine spitzenseitige und eine kopfseitige Flanke (18, 20) aufweist, wobei der kopfseitige Flankenwinkel (ßls ß2) größer als der spitzenseitige Flankenwinkel (α) ist und der spitzenseitige Flanken winkel (α) im Schaftbereich (8) und im Spitzenbereich (10) etwa gleich bleibt, während der kopfseitige Flankenwinkel (ßi, ß2) im Spitzenbereich (10) größer als im Schaftbereich (8) ist.
Abstract:
Die Erfindung bezieht sich auf eine durch Kaltwalzen geformte Befestigungsschraube aus niedrig legiertem Kohlenstoffstahl mit grossem Umformgrad gemäss einem Verhältnis Aussendurchmesser/Kerndurchmesser >1,2 und einem Verhältnis von Steigung/Aussendurchmesser >0,23 mit selbstfurchendem Gewinde für das Einschrauben insbesondere in Kunststoffe. Das Schraubenmaterial einer Schraube aus Stahl von ferritischem Gefüge enthält weitere Bestandteile mit gegenüber dem im Ferrit enthaltenen Kohlenstoff wesentlich höheren Kohlenstoffgehalt, wobei dieses Mischgefüge einen Kohlenstoffgehalt von max.0,42 Gewichtsprozenten und eine maximale Korngrösse entsprechend mindestens 2000 Körner/mm 2 , vorzugsweise mindestens 3000 Körner/mm 2 , mit durch das Kaltwalzen eingeprägten, aufrechterhaltenen Eigenspannungen aufweist.
Abstract:
The reverse barb system for screws and nails includes fasteners that are barbed to prevent backing out once driven into a workpiece or construction material, such as wood. A screw with barbed threads (10) has several barbed thread sections (20). Each barbed thread section is a section of thread having a leading edge (24) and a trailing edge (26), the trailing edge defining a barb to increase the screw's resistance to backing out once driven into place. A nail with a barbed point is a nail having one or more barbs formed in the nail's point. Each barb is defined by a leading edge and a trailing edge. The barb's trailing edge forms an acute angle with the longitudinal axis of the nail. The barbs extend from the nail shank to prevent the nail from backing out.
Abstract:
The present invention is directed to a deck screw intended for use with composite lumber, although it can be used with other wood products, such as pressure treated lumber, the deck screw of the present invention may be provided with a head and a shaft that has two regions of varying diameter. The upper region has threads that exceed the number of threads of the lower shaft, on a unit length basis. The treads of the upper shaft may be configured in an inverted buttress design. The lower region of the shaft terminates at a tapered distal end having a pointed tip that leads the screw through the wood material. Threads are provided on the lower region of the shaft. The head of the screw is provided with an upper surface, a lower surface, and a crown that extends around the perimeter of the head. The crown extends beyond the lower surface of the head, forming a recessed region between the lower edge of the crown and the shaft of the screw. The head may also be provided with an undercut. Further, the head of the screw may be provided with a square driver opening that permits the persons installing the screw to use a square bit. For instance the opening may be a #2 square driver opening. It should be understood that Phillips heads or flat heads in various sizes might also be employed.
Abstract:
A device for positioning a joinery fastener (74) in a joinery member (33) for later use in forming a joinery assembly. The fastener positioning device (41) includes a feed magazine (82) for feeding joinery fasteners (74) to a gripping apparatus (83). The gripping apparatus (83) is positioned to receive the fasteners (74) and is adapted to releasably grip individual fasteners (74) below the fastener head (86) tohold the fasteners (74) in a controlled, indexed relation to the gripping apparatus (83). The gripping aparatus is movable between a fastener gripping position to a fastener placement position while the pointed end (88) of the fastener (74) remains in indexed relation, and a placement arm (92) is formed to urge the fastener (74) forming the gripping apparatus (83) into interference fit with the joinery member (33).