The invention relates to a chamfering tool (4) for chamfering workpiece toothings (22), comprising a helical toothing having, for each flight, a plurality of teeth (5) with a geometrically defined cutting edge and having a tooth profile (8, 9; 8, 9) which is designed for single-flank machining in rolling machining engagement with the workpiece toothing and asymmetrical as viewed in the axial section of the tool. The invention further relates to a chamfering system (100), to a gear-cutting machine, and to a method for producing a chamfer on the tooth edges of a tooth flank side of a workpiece toothing.

The invention relates to a method for machining a workpiece, wherein, in particular in the skiving process, a toothing is produced on the workpiece in a first machining operation, in which a toothed cutting wheel, which rotates about the axis of rotation thereof and, on a first end face, comprises cutting edges on the toothing thereof, is coupled in a rolling manner to the workpiece which rotates about the axis of rotation thereof, and a cutting movement of the cutting edges, which has directional components in parallel with the workpiece axis, ends at an axial side of the workpiece toothing, the cutting edges of the cutting wheel forming a first operating region which can be positioned with respect to the workpiece by means of movement axes, and in which, in a second machining operation using a second operating region, the workpiece is machined on the side of the workpiece toothing at which the movement ends, wherein the second operating region can be positioned with respect to the workpiece by means of the same movement axes as the first operating region, and in particular is coupled for movement to the first operating region.

A hard coating includes two first crystalline phases, and a second crystalline phase containing AlN of a wurtzite-type crystal structure disposed therebetween. The two first crystalline phases each include, independently, a laminate structure having a Ti.sub.1-x1Al.sub.x1N phase having a sodium chloride-type crystal structure, and an Al.sub.x2Ti.sub.1-x2N phase having a sodium chloride-type crystal structure that are alternately stacked. An Al composition ratio x1 satisfies a relationship 0.5x10.75, and an Al composition ratio x2 satisfies a relationship 0.75<x20.95. The laminate structure includes a region in which an Al concentration periodically changes along a stacking direction of the Ti.sub.1-x1Al.sub.x1N phase and the Al.sub.x2Ti.sub.1-x2N phase. In this region, a difference between a maximum value of the Al composition ratio x2 and a minimum value of the Al composition ratio x1 is greater than 0.25.

A gear machining apparatus causes a machining tool and a workpiece to rotate at a high speed in synchronization with each other to machine a highly accurate gear through cutting. The machining tool is manufactured such that each of pitches between tool blades of the machining tool is an integer multiple of a pitch between teeth of the gear, the integer multiple being equal to or larger than double. By using the machining tool for cutting performed by the gear machining apparatus, the number of the tool blades of the machining tool, which are brought into contact with the workpiece at the same time, is reduced. Thus, it is possible to suppress occurrence of self-excited vibrations during cutting by reducing the cutting resistance. Thus, it is possible to enhance the tooth trace accuracy of the gear.

A gear machining apparatus causes a machining tool and a workpiece to rotate at a high speed in synchronization with each other to machine a highly accurate gear through cutting. The machining tool is manufactured such that each of pitches between tool blades of the machining tool is an integer multiple of a pitch between teeth of the gear, the integer multiple being equal to or larger than double. By using the machining tool for cutting performed by the gear machining apparatus, the number of the tool blades of the machining tool, which are brought into contact with the workpiece at the same time, is reduced. Thus, it is possible to suppress occurrence of self-excited vibrations during cutting by reducing the cutting resistance. Thus, it is possible to enhance the tooth trace accuracy of the gear.

There is provided a tool for efficiently cutting a face gear to be meshed with a helical gear. When a circular tooth thickness of a tooth tip of a cutting edge portion is represented as S.sub.atSC, a circular tooth thickness on a virtual outside diameter of a tooth profile of the helical gear in a cross-sectional view perpendicular to an axis is represented as S.sub.at, a helix angle on the virtual outside diameter of the tooth profile of the helical gear in a cross-sectional view by a plane perpendicular to the axis is represented as .sub.a, and a face width of the cutting edge portion is represented as b.sub.sc, $b_{\mathrm{SC}}\frac{s_{\mathrm{at}}-s_{\mathrm{atSC}}}{\tan {}_a}$
is satisfied.

A coolant delivery assembly configured for use with a gear cutter tool that cuts gear teeth into a workpiece to form a gear includes a retaining cooling nut, a tool holder and a coupling member. The retaining cooling nut has a nut body that defines a plurality of coolant flow passages therein. The tool holder supports the gear cutter tool. The coupling member couples the retaining cooling nut to the mount. The retaining cooling nut is configured to receive coolant and deliver the coolant through the plurality of coolant flow passages and direct the coolant toward the gear cutter tool.