A method for manufacturing a multi-functional fastener includes a preparing operation, a forming operation and a threading operation. The preparing operation prepares a metal blank cut from a length of a metal material. The forming operation is executed so that the metal blank forms a shank, a head, and a drilling portion connected to the shank. The threading operation is executed to roll the metal blank with a thread rolling set having two opposite rolling plates. Each rolling plate has slit grooves and convex units arranged in alternation. Each of the convex units has protrusions each situated between two adjacent slit grooves, which allows the threading operation to equip the shank of the metal blank with thread convolutions, slots formed between the thread convolutions for helping quick removal of chips, and main ribs formed between any two adjacent slots for increasing cutting efficiency.

A rolled thread screw includes: a screw part having, on an outer circumferential part of the screw part, thread crests and thread grooves disposed alternately along an axial direction of the rolled thread screw; and a columnar part adjoining at least one of both sides of the screw part in the axial direction. An axial end surface of the columnar part is provided with: a first concave surface concave in the axial direction; a second concave surface positioned to an outer circumference of the first concave surface and being concave in the axial direction; and a salient part positioned on a boundary between the first concave surface and the second concave surface and projecting further than a bottom of the first concave surface and a bottom of the second concave surface, the salient part extending in an arc-like shape along a circumferential direction of the columnar part as viewed in the axial direction.

A rolled thread screw includes: a screw part having, on an outer circumferential part of the screw part, thread crests and thread grooves disposed alternately along an axial direction of the rolled thread screw; and a columnar part adjoining at least one of both sides of the screw part in the axial direction. An axial end surface of the columnar part is provided with: a first concave surface concave in the axial direction; a second concave surface positioned to an outer circumference of the first concave surface and being concave in the axial direction; and a salient part positioned on a boundary between the first concave surface and the second concave surface and projecting further than a bottom of the first concave surface and a bottom of the second concave surface, the salient part extending in an arc-like shape along a circumferential direction of the columnar part as viewed in the axial direction.

A hollow screw and related process of making is provided, wherein the hollow screw is formed from a generally circular corrosion resistant stainless steel disk cut from flat roll stock. The hollow screw includes a head and an elongated and hollow shaft having a wall thickness between about 0.2 to about 0.7 millimeters extending therefrom and defining a shank portion and a threaded portion having a plurality of threads thereon with a rotational drive mechanism configured to facilitate tightening via the threads. The process involves annealing to soften the stamped hollow screw, followed by thread rolling, and then age hardening the hollow screw. As such, the resultant hollow screw is relatively lightweight, about 50% the mass of a solid core screw made from the same material, with a sufficient thread strength to meet most aerospace applications and contributes to important aircraft fuel economy.

The invention relates to a tangential thread rolling head comprising two fork-like rolling head arms each rotatably coupled with a thread roll by an axle. The thread rolls respectively engage with a pinion and can be pushed laterally into an assembled position into the rolling head arms before installation of axles, in which one of the axles can be pushed into a bearing bore hole of the thread rolls. The thread rolls and the pinions have interacting catches that are configured such that each of the thread rolls can only be pushed laterally into the assembled position in a single defined rotary position.

The invention relates to a tangential thread rolling head including two rolling head arms having a thread roll rotatably mounted on an axle. The thread rolls are configured to engage with a gear and be pushed laterally into an assembled position into the rolling head arms before the installation of the axles and the axles can be pushed into a bearing bore hole of the thread rolls. The two thread rolls have identical thread profiles that are offset with respect to each other when the thread rolls are in the assembled position.

The present invention relates to rope drums for winding and unwinding ropes, having a drum shell, to which end disks are fastened at the end faces, and to rope winches having such rope drums. The invention also relates to a method for producing such a rope drum. According to the invention, the drum shell is seamlessly rolled from an annular workpiece blank by means of a rope groove profile embossed in a non-cutting manner.

A method for forming a stop flange on a self-tapping screw includes locating a shank of a self-tapping screw between two threading dies, fixing one of the two threading dies and moving the other one of the two threading dies to work the shank, the external thread forming section of each of the threading dies performing threading to form an external thread on the shank, inserting the insert and the recessed corner of each of the threading dies into a top of the external thread to form a groove in the shank, and the insert of each of the threading dies gradually squeezing downward an extruded portion that is formed during formation of the groove to form a stop flange on the shank. Thus, the shank is integrally formed with the stop flange, to stop an excessive movement of the external thread.

A method for manufacturing a multi-functional fastener includes a preparing operation, a forming operation and a threading operation. The preparing operation prepares a metal blank cut from a length of a metal material. The forming operation is executed so that the metal blank forms a shank, a head, and a drilling portion connected to the shank. The threading operation is executed to roll the metal blank with a thread rolling set having two opposite rolling plates. Each rolling plate has slit grooves and convex units arranged in alternation. Each of the convex units has protrusions each situated between two adjacent slit grooves, which allows the threading operation to equip the shank of the metal blank with thread convolutions, slots formed between the thread convolutions for helping quick removal of chips, and main ribs formed between any two adjacent slots for increasing cutting efficiency.

A method of manufacturing a rack bar includes: a rolling die abutment step of bringing a pair of rolling dies into abutment against an intermediate portion of a workpiece; and a ball screw groove forming step of forming a ball screw groove in the workpiece by moving the workpiece relative to the pair of rolling dies so that a region of the workpiece against which the pair of rolling dies is brought into abutment is moved from the intermediate portion toward a first end portion of the workpiece.