A gear machining device is provided which can machine an accurate gear by a cutting process by synchronously rotating a machining tool and a workpiece at a high speed. A machining tool includes roughing cutting teeth for roughing bottom lands and right and left side faces of teeth of a gear, right side face finishing cutting teeth for finishing the right side faces of the teeth, and left side face finishing cutting teeth for finishing the left side faces of the teeth. The cutting teeth thus cut different parts of the teeth of the gear. This can reduce cutting resistance and suppress self-vibration during the cutting process, thereby improving tooth trace accuracy of the gear.

A method and a device for gear cutting a work wheel includes a cutting wheel with cutting teeth, which is rotatably driven on a tool spindle about a tool spindle axis. The cutting teeth engage into the work wheel, which is rotatably driven on a workpiece spindle about a workpiece axis that intersects the tool spindle axis. In rough cuts, tooth spaces between left and right tooth flanks of teeth of the toothing are deepened via a change in axial distance of the tool spindle axis and the workpiece axis. In a first finishing cut, only the left tooth flank is precision machined with a chip removal point moving from top to base of the tooth with gear skiving movement. In a second finishing cut, only the right tooth flank is precision machined with a chip removal point moving from top to base of the tooth with gear skiving movement.

A method and a device for gear cutting a work wheel includes a cutting wheel with cutting teeth, which is rotatably driven on a tool spindle about a tool spindle axis. The cutting teeth engage into the work wheel, which is rotatably driven on a workpiece spindle about a workpiece axis that intersects the tool spindle axis. In rough cuts, tooth spaces between left and right tooth flanks of teeth of the toothing are deepened via a change in axial distance of the tool spindle axis and the workpiece axis. In a first finishing cut, only the left tooth flank is precision machined with a chip removal point moving from top to base of the tooth with gear skiving movement. In a second finishing cut, only the right tooth flank is precision machined with a chip removal point moving from top to base of the tooth with gear skiving movement.

A gear machining apparatus includes a machining tool having a plurality of protruding tool edges on an outer periphery of the machining tool, and driving apparatuses that form a tooth on a work piece by rotating the machining tool around a central axis thereof, rotating the work piece W around a central axis thereof, and moving the machining tool relative to the work piece. Radial outer faces of the protruding tool edges form multiple steps that are parallel to the central axis of the machining tool such that the diameter of the machining tool increases in a stepwise manner from a tool leading end toward a tool base end of the machining tool.

This gear cutting machine, which is equipped with a cutter (15), a cutter spindle motor (11) that causes, via a crank mechanism (13) and a cutter spindle (16), the cutter (15) perform a stroke operation, and a motor control unit (10) that controls the rotation angle of the cutter spindle motor (11), is provided with a relieving spindle motor (12) that causes the cutter (15) to move in the direction of a relieving spindle via a link mechanism (four-joint link mechanism (14)). The motor control unit (10) controls the rotation angle of the relieving spindle motor (12) on the basis of the rotation angle of the cutter spindle motor (11). Consequently, a gear cutting machine that accurately controls the relieving operation in accordance with a desired shape, such as crowning and tapering of a gear to be cut can be provided.

A gear machining apparatus includes a machining tool having a plurality of protruding tool edges on an outer periphery of the machining tool, and driving apparatuses that form a tooth on a work piece by rotating the machining tool around a central axis thereof, rotating the work piece W around a central axis thereof, and moving the machining tool relative to the work piece. Radial outer faces of the protruding tool edges form multiple steps that are parallel to the central axis of the machining tool such that the diameter of the machining tool increases in a stepwise manner from a tool leading end toward a tool base end of the machining tool.