Kennametal Inc.

Yamawa Manufacturing Limited

Yamawa Mfg. Co., Ltd.

Sadayuki Akaki

Willard E Henderer

Stephen Michael George

Vladimir David Volokh

Anakkavur T Santhanam

Steven R Burns

Masao Mitsui

A cutting tool that includes an elongate body that has a forward end and a rearward end. The elongate body has a fluted portion that beginning near and extends in a rearward direction from the forward end. The fluted portion has a flute that defines a cutting edge. The flute presents a concave cutting face wherein the concave cutting face is defined by a first radius. The flute further presents a concave core surface adjacent to the concave cutting face wherein the concave core surface is defined by a second radius. The flute presents a convex heel surface adjacent to the concave core surface wherein the convex heel surface is defined by a fourth radius.

Spiral flute tap

A cutting tap that has an elongate tap body with a fluted section at the axial forward end thereof wherein the fluted section includes a chamfered fluted section and a finishing fluted section. Each cutting thread in the chamfered fluted section has a cutting face disposed at a cutting face angle that becomes more negative the more axially rearward the cutting thread is from the axial forward end of the chamfered fluted section. Each cutting thread in the finishing fluted section has a cutting face disposed at a finishing cutting face angle that is essentially equal. The finishing cutting face angle is more negative than the cutting face angle for the cutting thread at the axial rearward termination of the chamfered fluted section.

Cutting tap and method of making a cutting tap

A high-speed forming tap () for cutting and forming a female screw by cutting edges (E) of a screw portion () 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 () of the screw part (). The chamfers (CF) start from the cutting edge (E) and are provided along ridgelines (R) between a crest face () and flanks, or a following flank () and a leading flank (). 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.

High-speed forming tap

A precision cemented carbide threading tap is designed for use in precision tool holders in synchronous high speed tapping. The precision tap includes a fully cylindrical shank without the aid of squares, flats or other notches. The precision tap further includes a threaded body portion and a threaded cutting chamfer portion. The threaded body portion and the threaded cutting chamfer portion of the precision tap are concentric to the cylindrical shank of the tap within a runout of 10 microns. The precision cemented carbide threading tap improves the accuracy, life and speed by which internal screw threads are produced.

Precision cemented carbide threading tap

A coated carbide tap comprises a substrate consisting of tungsten carbide cemented with 12 to 16% by weight cobalt with additions of small amounts of transition metal carbides added to restrain grain growth, and may also contain low levels of impurities that might be picked up during processing. The substrate is coated with a layer of metal nitrides, carbides, carbonitrides, borides and/or oxides, the metal being chosen from one or more of the following: aluminum, silicon and the transition metals from Groups IV, V, and VIof the Periodic Chart. The coating may comprise a monolayer and/or alternating layers optionally with varying chemical composition. To reduce friction, a top outer layer comprised of molybdenum disulphide; molybdenum disulphide and transition metals, or any combination thereof; carbon; carbon and transition metal carbides, or any combination thereof; carbon and a transition metal, or any combination thereof; and/or carbon nitride may be either co-deposited as a single layer or deposited in multiple or alternating layers to the coating. The coated carbide tap of the invention can be used at cutting speeds at least three times faster than conventional taps without chipping or breaking the tap.

Growing community of inventors

Fukushima, Japan

Sadayuki Akaki