Abstract: A method for producing a threaded bore in a workpiece with a tapping tool bit, which, at its drill bit tip, has a main cutting lip and a thread profile trailing in a tapping direction (I) with at least one thread cutting tooth, wherein, in a tapping stroke (G), the main cutting lip produces a core hole and, at the same time, the thread profile forms an internal thread at the inner wall of the core hole until reaching an intended thread depth (tG), specifically with a tapping feed (fG) in the tapping direction (I).

Abstract: A method for producing a tapped bore in a workpiece with a tap drill bit, which, at its drill bit tip, has a primary cutting edge and a thread profile trailing in a tap drilling direction. The method has a tap drilling stroke, in which the tap drill bit is driven into the workpiece with a tap drilling advance in the tap drilling direction and at a tap drilling rotational speed synchronized therewith, and the tool-primary cutting edge produces a core-hole bore, and the thread profile of the tool bit forms an inner thread at the inner wall of the core-hole bore. In the tap drilling stroke, shavings are produced, which are conveyed in a shavings discharge direction, which is oppositely directed to the tap drilling direction, out from the tapped bore and collide here with thread flanks of the inner thread that face the shavings that are discharged.

Abstract: A method of machining a screw is provided that is capable of preventing formation of a protruding section at a thread tip section. A thread is formed by cutting on a cylindrical body, and a surface of the thread is plastically deformed by rolling. Because of the cutting, a width between-side surfaces of a thread tip section is in a narrowed state as compared to a normal width. This width is narrowed toward a tip of the thread while a thread body section has a width expanded as compared to a normal width. Consequently, the side surfaces are formed to bulge by an excess thickness portion as compared to normal side surfaces. The rolling plastically deforms both side surfaces to cause the excess thickness portion to plastically flow toward the side surfaces.

Abstract: Flutes defining inside diameter finishing edges are formed in middle portions of relief parts arranged in three linear arrays which are located between a plurality of linear arrays of protruding parts in a chamfered end section, about an axis 0, and the inside diameter finishing edges are formed along one of opposite open-end edges of each flute which is located on an upstream side of the flute as seen in a tap rotating direction A, and are offset by a predetermined angle ? in the tap rotating direction A with respect to the protruding parts in the chamfered end section. Accordingly, all of the plurality of linear arrays of protruding parts in the chamfered end section can be used to form the internal thread by plastic deformation of an inner circumferential surface of a hole to be tapped.

Abstract: A threading cutting insert achieves high shape accuracy of a screw to be processed, and saves on manufacturing cost. Therefore in the threading cutting insert, a plurality of tooth-shaped cutting edges are formed in a cross ridge line portion between a rake face and flanks formed in a cutting side face, wherein the plurality of mountain-shaped cutting edges provides at least one finishing cutting edge for transferring a shape of a screw, and at least one roughing cutting edge formed in a tooth shape smaller than that of the finishing cutting edge. A flank of the finishing cutting edge includes a first flank, and a second flank having a clearance angle larger than that of the first flank, wherein the finishing cutting edge, the first flank, and the second flank are sequentially provided in that order from the rake surface in a direction of a lower surface of the insert.

Abstract: The present disclosure is directed toward a compound relief tap, and more specifically, to a compound relief tap with domains made of a plurality of consecutive threads where each domain has different properties associated with variable thread parameters and variable geometrical arrangements such a variation of a taper angle and relief angles for different portions of domain threads or between domains. In a first embodiment, all of the threads in a domain have a given geometrical arrangement. In a second embodiment, several of the threads of the domain possess the geometrical arrangement. In a third embodiment, only the thread of the domain possesses the geometrical arrangement. And in a fourth embodiment, alternative threads in the domain possess the geometrical arrangement. What is also contemplated is a variation in geometrical arrangement between successive domains for any of these threaded domains.

Abstract: The present disclosure is directed toward a compound relief tap, and more specifically, to a compound relief tap with domains made of a plurality of consecutive threads where each domain has different properties associated with variable thread parameters and variable geometrical arrangements such a variation of a taper angle and relief angles for different portions of domain threads or between domains. In a first embodiment, all of the threads in a domain have a given geometrical arrangement. In a second embodiment, several of the threads of the domain possess the geometrical arrangement. In a third embodiment, only the thread of the domain possesses the geometrical arrangement. And in a fourth embodiment, alternative threads in the domain possess the geometrical arrangement. What is also contemplated is a variation in geometrical arrangement between successive domains for any of these threaded domains.

Abstract: A high-speed forming tap (1) for cutting and forming a female screw by cutting edges (E) of a screw portion (2) fed in synchronous with the rotation of a machine tool. The high-speed forming tap is characterized in that chamfers (CF) are provided at a bevel lead (2a) of the screw part (2). The chamfers (CF) start from the cutting edge (E) and are provided along ridgelines (R) between a crest face (2e) and flanks, or a following flank (2c) and a leading flank (2d). This structure enables the shape of the edges of the tap leading portion to be stably maintained and high-speed, smooth female screw cutting with high accuracy, and provides a tap with long life.

Abstract: A threading tap for cutting threads in blind holes includes an elongated body with a central axis, the body having at a rear end a connector portion, and having at a front end a threading portion. The threading portion is provided with at least one helical thread-cutting structure and interconnected flank portions defining at least one helical flute which interrupts the helical thread cutting structure. The flank portions present exposed surfaces that are steam tempered. The rest of the tap is coated by PVD.

Abstract: A threading tap for cutting threads in blind holes includes an elongated body with a central axis, the body having at a rear end a connector portion, and having at a front end a threading portion. The threading portion is provided with at least one helical thread-cutting structure and interconnected flank portions defining at least one helical flute which interrupts the helical thread cutting structure. The flank portions present exposed surfaces that are steam tempered. The rest of the tap is coated by PVD.

Abstract: A thread cutting tool for cutting female threads includes a shaft and a cutting section composed of several groups of cutting teeth alternating with chip grooves. At least some of the teeth, preferably teeth disposed in a front region of the tool, have undercuts in their flanks which define radial steps, each step spaced circumferentially from a cutting edge of the respective tooth in order to form a space which facilitates the escape of cuttings.

Abstract: A thread forming tap comprising a shank section, a body section extending longitudinally from the shank section, a helical thread formed on the body section having radially converging flank portions and an undercut ramp formed in at least one of said flank portions at a predetermined angle.

Abstract: A cold forming tap with an internal finish cutting edge includes an external thread portion having radially outwardly protruding portions and relief portions which are alternately located in a helical direction in which an external thread extends. The protruding portions are forced into a surface of a prepared hole which has been previously formed through a workpiece, for thereby forming an internal thread on the surface. The improvement comprises: at least one of the protruding portions having a root diameter larger than that of the other of the protruding portions, the at least one of the protruding portions being removed down to a root of the external thread, and a flute being formed in a portion corresponding to the root of the at least one of the protruding portions, so as to provide the cutting edge in the portion corresponding to the root.

Abstract: A high durability taper tap for pipe threads which can cut threads in a pipe made of hard materials having hardness of approximately 50 HRC. The sum &Sgr;&ggr; of the width angle of cutters is large, approximately 130°, thereby achieving high strength and rigidity are achieved. Since rake angle of the cutting edge &agr; is approximately −20°, cutter angle &bgr; defined by the rake face and the peripheral relief becomes more than 90° so that the strength and rigidity of a cutting edge are enhanced. In addition, since a taper of the bottom of flutes is in a ratio of 1/16, approximately equal to that of the thread portion, the rake angle &agr; of all of the cutting edges 6 is uniform so that all of the cutting edges can equally cut the threads. Further, the diameter Df of the bottom of the flutes of the top end portion is approximately 60% of the smaller end of the thread portion, which is larger than that of the common tapping tool.

Abstract: A lordotic implant has a frusto-conical shape with external threads. Prior to placement of the implant, vertebrae are distracted in a manner to provide a desired lordosis between the vertebrae. The pre-distracted vertebrae are then tapped to provide a tapped bore having a geometry matching the conical geometry of the implant. The threaded implant is then placed within the pre-tapped conical bore.

Abstract: A thread repair tool and method of manufacturing are disclosed, along with a method for repairing damaged threads of a bolt, stud, or the like. The thread repair tool includes a pair of chaser sections each having a threaded inner diameter to match the threads of the bolt or stud to be repaired. Each chaser section has a tapered outer diameter and a longitudinal keyway in the tapered outer diameter. A driver is provided in which its inner diameter is tapered to match the outer diameter of the chaser sections. The tapered driver and chaser sections are locked together with a pair of keys, and the arrangement provides positive, force transferring engagement between the driver, the chaser sections, and the bolt or stud. The arrangement translates longitudinal pressure applied to the driver into radial pressure forcing the chaser sections tightly against the bolt or stud to be repaired.

Abstract: A nib tap configuration in which the thread turns are of progressively increasing pitch diameter over a range of size limits associated with a standard basic pitch diameter. A particular size limit can be provided by grinding off the turns of a larger limit size. A family of taps covering an extended range of pitch diameter size limits allow selection over the extended range.

Abstract: There is a tap whose thread portion 2 forms a cutting section 5 and a guiding section 6 and is provided on a plurality of adjacent thread teeth of the cutting section 5 with a relief 8. It is desirable that a further machining measure be provided for the tap whereby favorable compromises can be obtained with respect to guidance and friction. This is achieved in that the relief 8 of the adjacent cutting-section 5 thread teeth--seen in a longitudinal direction--have a clearance angle which varies increasingly or decreasingly. Varying the relief enables the requirements with respect to avoiding incorrect tapping and avoiding friction-generated cold welding to be met and matched up in an improved manner.

Abstract: There is a tap having a tapered threaded portion 2 whose thread teeth 4 located in the tapered section are provided with a relief arranged at a clearance angle. It is desirable that the cutting moment and friction should decrease to the back towards the greater diameter. This is achieved in that the clearance angle of the thread teeth 4 in the tapered section 2 remains constant or increases towards the back. A simple machining measure permits the cutting moment and friction to be variably controlled over a wide range.

Abstract: A self-locking fastener includes a male member, such as a bolt, having a standard, helical, male thread of constant diameter which is deformed by the special female locking threads of a female member, such as a nut. The female threads are defined by leading and trailing flanks which converge to provide a truncated root that frictionally engages and deforms a portion of the male crest. The trailing flanks of the male and female threads are inclined at the same angle and frictionally engage each other throughout their entire depth. The leading flanks of the male and female threads diverge away from each other to provide a space adjacent the truncated female root for receiving the deformed portion of the male crest therewithin. The deformed portion of the male crest and the full engagement of the trailing flanks produces firm metal-to-metal contact between the members throughout the entire length of the female thread, thereby procluding lateral movement of one member relative to the other.

Abstract: A self-feeding, self-aligning drill bit includes a working end with a cylindrical portion having a desired cutting diameter and a conical threaded portion extending therefrom terminating in a threaded tip. The diameter of the threaded portion increases from the tip toward the cylindrical portion such that it approaches the diameter of the cylindrical portion at their juncture. One or more flutes extend longitudinally through both the cylindrical portion and the threaded portion to form one or more cutting edges extending at an angle relative to the axis of the drill bit. The threaded portion may include one or more peripheral grooves staggered along the length of the threaded portion to provide additional cutting edges to reduce cutting torque. The threaded portion not only pulls the bit into the workpart but also the cutting edges thereof function to cut a preliminary hole and also cut apart the workpart debris to significantly reduce chip size.

Abstract: A fluted screw tap has a plurality of thread lands each with a pair of outwardly facing flanks. Each flank of a pair has a different asymmetric relief ground flank surface extending in a spiral form along the length of the thread land. Each thread land has a corner resting against the cut thread. Each of the flank surfaces in a pair has a different relief grinding angle extending along the threaded flank and the angle approaches the zero value at the end of the thread land where the corner resting against the cut thread is located.

Abstract: An elongated rectilinear tool for formation of a threaded hole in ductile metal by the coining or flowing of the metal. The tool typically is employed to form through threaded holes in a piece of ductile metal, and features a working end having a boring tip or drill point and a spade section having a flat shank with grooves in its lateral edges. The spade section holds the drill point and extends back a short distance from the working end. The diameter of the tool then enlarges slightly at a small inclined section which is followed by a longer coining tap section. The coining (flowing) of metal forms a thread on the previously smooth wall of the drilled hole, with peaks or crests, and roots. The lateral grooving of the spade section tracks, i.e. fits, into the fully formed threading as the present tool is screwed out.

Abstract: A male screw thread-formed member such as an insert having a thread cutting action has an exterior peripheral portion of substantially full V-thread form along which two or more angularly spaced apart flutes extend from one or both ends of the member, the member being provided with at least one non-helical rib initially of generally annular peripheral V-form at one or both ends thereof and on which is formed a varying reduced V-thread form which follows a helix corresponding to that of the full thread form whereby pointed cutting formations providing peaks of different radial heights and with some of them of offset disposition relative to the helix are formed on the or each rib at the flutes for effecting a distributed thread cutting action thereat, e.g., for use in thermo-setting plastic material.

Abstract: A drill bit for drilling holes of a given diameter in wood or similar material comprising a drill body having a series of stepped cylindrical portions increasing in diameter from the small entry end of the drill to the full diameter of the hole to be drilled whereby the drill body is of generally conical shape. Each of the cylindrical portions extends in a helical direction, and a single flute extends generally lengthwise of the drill body to provide cutting edges for the cylindrical portions and a discharge path for material cut from the workpiece. The flute extends generally parallel to the axis of the drill and forms approximately a right angle in transverse cross section, occupying approximately one fourth of the cross sectional area of the drill body. A male thread extends helically along each of the cylindrical portions excepting the largest full diameter portion and projects radially outwardly from each of such portions to engage the walls of the workpiece and thus feed the drill through the workpiece.

Abstract: A thread forming tap comprising a shank section, a body section extending longitudinally from the shank section, a helical thread formed on the body section and having radially outwardly converging flank portions which define an inclined ramp arranged at a preselected angle to the axis of the tap and adapted to form a complementary inclined locking ramp on the thread to be formed by the tap.

Abstract: A thread forming tap comprising a shank section, a body section extending longitudinally from the shank section, a helical thread formed on the body section and having radially converging flank portions which define an inclined ramp area arranged at a preselected angle to the axis of the tap and adapted to form a complementary inclined ramp at the root of the thread to be formed by the tap.