A screw includes a shank and a head defining a recess. The recess includes a central space zone, a plurality of outer space zones, and a plurality of intermediate space zones. The central space zone extends downwardly from a top face to an inner bottom of the head. The outer space zones extend radially from the central space zone to be arranged around the central space zone. Each of the outer space zones is defined by two side surfaces and a first arc-shaped surface therebetween. The intermediate space zones are arranged around the central space zone, between the outer space zones. Each of the intermediate space zones is defined by a second arc-shaped surface, which is joined to two adjacent side surfaces of two adjacent outer space zones respectively by two third arc-shaped surfaces. Furthermore, a punch is provided to make recesses for screws according to the present invention.

A driver for applying torque to threaded fasteners has a plurality of teeth extending along and projecting outwardly from a longitudinal axis of a body on which the teeth are located. The teeth have a helical twist about the longitudinal axis. Each tooth has an angularly oriented engagement surface which is engageable with similarly angularly oriented surfaces within recesses in the head of a compatible fastener. When the driver engages the recesses torque applied to the driver draws the driver deeper into the recesses as the engagement surfaces react against and slide over the angularly oriented surfaces within the recesses. The torque also causes the fastener to turn and advance or retract depending upon the sense of the torque and the angles of the engagement surfaces and the angles of the surfaces within the recesses. The fastener and its method of manufacture are also disclosed.

A rolled-thread bolt production method includes: forming a steel wire into a workpiece having a prescribed unthreaded-bolt shape; forming a threaded-portion on the workpiece through thread rolling; and performing shot blasting on an entire surface of the workpiece after forming the threaded-portion.

A method of producing shaped parts includes drawing in the wire in cycles conveying the wire; severing wire portions in cycles; gripping and feeding the wire portion into work area; shaping the wire portion in multiple stages to form a shaped part with shank and head portions; ejecting formed shaped parts in cycles; transporting the fully formed shaped parts with a pneumatic conveyor system including a transporting pipe with an insertion opening: arranging the insertion opening near an ejector system such that the finished shaped parts can be inserted into the insertion opening directly in a positionally oriented manner by the ejector system; successively feeding the finished shaped parts into the transporting pipe by the ejector system; taking up the shaped parts inserted into the transporting pipe by suction into the transporting pipe; and pneumatically transporting the shaped parts through the transporting pipe in a direction of a subsequent station.

A metric self-tapping locking screw comprises a screw head which is connected to a thread locking body by a screw rod. The thread locking body and the self-tapping tip are provided with a screw thread on the surface. The self-tapping tip is arranged at the root of the thread locking body; the screw thread adopts the basic structure of the standard ordinary triangular thread. The flank angle back to the fastened surface is 15-20 and the flank angle of the screw thread facing the fastened surface is 30. The metric self-tapping locking screw in the Invention make the installed parts to be fastened have higher axial clamping force and static loosing moment, which solves the attenuation problem of axial clamping force and static moment of fastened parts.

A metric self-tapping locking screw comprises a screw head which is connected to a thread locking body by a screw rod. The thread locking body and the self-tapping tip are provided with a screw thread on the surface. The self-tapping tip is arranged at the root of the thread locking body; the screw thread adopts the basic structure of the standard ordinary triangular thread. The flank angle back to the fastened surface is 15-20 and the flank angle of the screw thread facing the fastened surface is 30. The metric self-tapping locking screw in the Invention make the installed parts to be fastened have higher axial clamping force and static loosing moment, which solves the attenuation problem of axial clamping force and static moment of fastened parts.

A combined anchor and rebar assembly includes a rebar, a bolt head, an anchor bolt and a weld joint. The bolt head is formed integrally as one piece with an end of the rebar. The anchor bolt includes a threadless portion and a threaded portion. The threaded portion has a diameter smaller than that of the threadless portion and is formed with a screw thread. The weld joint joins another end of the rebar to the threadless portion in a manner that the rebar and the threadless portion are aligned along an axial line. The weld joint has a cross section larger than that of the threadless portion and projects radially from the rebar and the threadless portion. A method of producing the combined anchor and rebar assembly is also disclosed.

A combined anchor and rebar assembly includes a rebar, a bolt head, an anchor bolt and a weld joint. The bolt head is formed integrally as one piece with an end of the rebar. The anchor bolt includes a threadless portion and a threaded portion. The threaded portion has a diameter smaller than that of the threadless portion and is formed with a screw thread. The weld joint joins another end of the rebar to the threadless portion in a manner that the rebar and the threadless portion are aligned along an axial line. The weld joint has a cross section larger than that of the threadless portion and projects radially from the rebar and the threadless portion. A method of producing the combined anchor and rebar assembly is also disclosed.

A combined anchor and rebar assembly includes a rebar, a bolt head, an anchor bolt and a weld joint. The bolt head is formed integrally as one piece with an end of the rebar. The anchor bolt includes a threadless portion and a threaded portion. The threaded portion has a diameter smaller than that of the threadless portion and is formed with a screw thread. The weld joint joins another end of the rebar to the threadless portion in a manner that the rebar and the threadless portion are aligned along an axial line. The weld joint has a cross section larger than that of the threadless portion and projects radially from the rebar and the threadless portion. A method of producing the combined anchor and rebar assembly is also disclosed.

A combined anchor and rebar assembly includes a rebar, a bolt head, an anchor bolt and a weld joint. The bolt head is formed integrally as one piece with an end of the rebar. The anchor bolt includes a threadless portion and a threaded portion. The threaded portion has a diameter smaller than that of the threadless portion and is formed with a screw thread. The weld joint joins another end of the rebar to the threadless portion in a manner that the rebar and the threadless portion are aligned along an axial line. The weld joint has a cross section larger than that of the threadless portion and projects radially from the rebar and the threadless portion. A method of producing the combined anchor and rebar assembly is also disclosed.