Abstract:
Eine selbstbohrende Schraube weist einen zylindrischen Schaft (1) mit einer kegelförmigen Schraubenspitze (2) auf, die in einer punktförmigen scharfen Spitze endet. Das Schraubengewinde (4) beginnt bereits in der Schraubenspitze (2) mit einem geringen Abstand von der punktförmigen Spitze. Zusätzlich zu dem Schraubengewinde (4) ist ein Zusatzgewinde (5) vorhanden, das ebenfalls in der Schraubenspitze, aber später als das Schraubengewinde (4), beginnt. Das Zusatzgewinde erstreckt sich nur über eine bis drei Windungen und endet unmittelbar nach dem Übergang zwischen der Schraubenspitze (4) und dem zylindrischen Schaft (1). Das Zusatzgewinde (5) weist im Verhältnis zu dem Schraubengewinde die gleiche Gewindeorientierung, eine geringere Steigung und eine kleinere Profilhöhe auf.
Abstract:
A fastener for use in concrete includes a shank and a head. The shank has a tip distal most from the head. The shank includes a first helical thread formation having a thread form thereon formed from two portions disposed upon opposite lateral sides of the thread form. The thread form has a root and the two portions include an alternating series of lobe members and base portions. The lobe members have a height as measured from the root and the base portions have a height as measured from the root. The height of the lobe members is greater than the height of the base portions and the height of the base portions is greater than zero. The fastener includes a second helical thread formation that is disposed adjacent to and spaced from the first helical thread formation.
Abstract:
A low energy wood screw that may be inserted quickly and using less energy than conventional screws. In various embodiments, the screw may include a countersunk head (30) having a recess (34) for accommodating a driving tool, a tapered neck (73), a plurality of crown ribs (74) extending over the head and neck, a lubricating coating, main threads (54) with a large thread lead, and lower threads (44) having an asymmetrical profile and extending onto a gimlet point.
Abstract:
A threaded screw fastener has a point (5), a shank (4) and a head (2). The point is a ballistic point. The shank comprises a linear travel area (6), preferably unthreaded, adjacent to the point and a threaded area (13) between the linear travel area and the head. The head is a bugle head formed with a Phillips-style recess configured to receive a driver or driving bit. The fastener is configured fasten a surface material to a substrate material and to be linearly driven into the materials before rotation of the fastener is required, thus reducing the number of rotations required to drive the fastener. The fastener is particularly suited to be used with powered driving tools that utilize both linear and rotating driving means.
Abstract:
A method for fastening components (18, 20) at critical joints in a motor vehicle powertrain. An unthreaded hole (22) is provided in a first component part (20), and a clearance hole (16) in a second component part (18). The shank (14) of a screw (10) that has a multi-lobed lead capable of creating a thread in the unthreaded hole is passed through the clearance hole to engage the multi-lobed lead with the unthreaded hole. Axial force and rotary torque are applied to the screw to cause the lead to form a desired helical thread in the unthreaded hole.
Abstract:
Die Erfindung betrifft eine Schraube (1) mit einem Gewindeschaft (2) mit einem Kraftangriff (4) zur Drehmomentübertragung und einer Schraubenspitze (6). Der Gewindeschaft (2) besteht aus einem Schaftkern (10) und einem selbstgewindeformenden Gewinde (12), und das Gewinde (12) ist als schraubenlinienförmig über den Schaftkem (10) verlaufende, von zwei in einer äusseren Gewindekante (14) zusammenlaufenden Flanken (15, 16) begrenzte Erhebung mit einer radialen Höhe (H) ausgebildet. Zumindest in einem Teilbereich des Gewindes (12) verläuft die äussere Gewindekante (14) in radialer Richtung mit einer Amplitude (U) wellenförmig zwischen Wellenbergen (20) mit der Höhe (H) und Wellentälem (22) mit einer um die Amplitude (U) reduzierten Höhe (h). Das Gewinde (12) weist zumindest im Bereich einer seiner Flanken (15/16) im Bereich der Wellentäler (22) der Gewindekante (14) die Oberfläche der Flanke (15/16) unterbrechende Einbuchtungen (24) auf, deren äussere Begrenzung die Gewindekante (14) ist, wobei das Gewinde (12) in den nicht von Einbuchtungen (24) unterbrochenen Bereichen der Wellenberge (20) der Gewindekante (14) jeweils einen bestimmten, zwischen den Flanken (15/16) gebildeten ersten Spitzenwinkel (a) und in den tiefsten Bereichen der Wellentäler (22) der Gewindekante (14) einen zweiten Spitzenwinkel (α‛) aufweist. Der erste Spitzenwinkel (a) zwischen den Flanken (15,16) liegt etwa im Bereich von 30° bis 35°, wobei der zweite Spitzenwinkel (α‛) 30° bis maximal 58° beträgt.
Abstract:
The tapping screw (1) has a screw thread (11) having a non-circular or notced shape. Accordingly, when the tapping screw is screwed into the prepared hole formed in the attached member such as a steel plate, etc., the contact area of the screw thread and the circumferential face of the prepared hole of the attached member can be reduced in comparison with the screw thread having a circular outer shape. Accordingly, the screwing torque can be reduced. Further, since the top portion of the screw thread of the square outer shape has a rising shape without being broken, the biting property of the screw thread with respect to the prepared hole formed in the attached member is improved so that a female screw can be precisely threaded on the inner circumferential face of the prepared hole by the male screw thread.
Abstract:
The tapping screw has a screw thread having a non-circular shape. Accordingly, when the tapping screw is screwed into the prepared hole formed in the attached member such as a steel plate, etc., the contact area of the screw thread and the circumferential face of the prepared hole of the attached member can be reduced in comparison with the screw thread having a circular outer shape. Accordingly, the screwing torque can be reduced. Further, since the top portion of the screw thread of the square outer shape has a rising shape without being broken, the biting property of the screw thread with respect to the prepared hole formed in the attached member is improved so that a female screw can be precisely threaded on the inner circumferential face of the prepared hole by the screw thread.
Abstract:
A tapping screw for soft material having a strip torque large sufficiently relative to a threading torque and also having and extended tightening torque allowance, characterized in that a flank of each thread in threading direction is formed steeper than that on the opposite side of that thread, the crest of each thread and the flank on the opposite side of that thread are curved, and also the areas connected to the bottom of each flank are curved, and both curved portions are formed so as to be connected in series at the bottom.