To provide a gear machining apparatus capable of correcting a tooth trace error without using a special tool when a hob cutter is cantilever-supported. A gear machining apparatus includes a hob cutter machining a tooth profile on a workpiece, a tool spindle device rotatably cantilever-supporting the hob cutter, a workpiece spindle device rotatably supporting the workpiece, a driving device moving the tool spindle device and the workpiece spindle device relatively to each other, a measuring device measuring the value corresponding to a bending amount of the hob cutter or a rotation synchronization shift of the workpiece spindle device with respect to the tool spindle device and a correction processing unit correcting a cutting amount of the hob cutter T or the rotation synchronization shift of the workpiece spindle device with respect to the tool spindle device based on the value measured by the measuring device.

A shaving processing method and apparatus for a gear are provided which reduce a load at the time of processing a tooth surface, thereby reducing a transmission error of the gear. Embodiments include a method for finishing the tooth surface of the gear in a state where the gear and a shaving cutter are engaged with each other and the shaving cutter is rotated. The gear has a pair of end surfaces facing each other in the tooth width direction. A first shaving step of processing the tooth surface is performed so that a processing region gradually expands from one end surface of the pair of end surfaces toward the other end surface, and a second shaving step of processing the tooth surface is performed so that a processing region gradually expands from the other end surface of the pair of end surfaces toward the one end surface.

A machining jig holds a workpiece with respect to a tool when machining the workpiece with the tool, the workpiece including a ridge that projects from an outer periphery of a cylindrical section in a radial direction and that extends so as to intersect a peripheral direction. The machining jig includes a holding jig that includes a cylindrical body section that is disposed at an outer periphery of the workpiece and a stopping section that projects inwardly from the body section and that stops a face of a surface of the ridge on a side where the tool leaves a processing portion of the ridge; and a coaxial base that is coaxial with the holding jig and to which the holding jig is coaxially fixed.

A machining jig holds a workpiece with respect to a tool when machining the workpiece with the tool, the workpiece including a ridge that projects from an outer periphery of a cylindrical section in a radial direction and that extends so as to intersect a peripheral direction. The machining jig includes a holding jig that includes a cylindrical body section that is disposed at an outer periphery of the workpiece and a stopping section that projects inwardly from the body section and that stops a face of a surface of the ridge on a side where the tool leaves a processing portion of the ridge; and a coaxial base that is coaxial with the holding jig and to which the holding jig is coaxially fixed.

The main spindle unit has a main spindle, a front bearing, a rear bearing, a front case for covering the front bearing, and a rear case for covering the rear bearing. The front case has a front body part for holding the front bearing and a front flange part extending radially outward from the front body part. The rear case has a rear body part for holding the rear bearing and a rear flange part extending radially outward from the rear body part. A front mounted surface, which can be brought into contact with a first mounting surface of a unit support table, is formed on the front flange part so as to face the front side thereof. A rear mounted surface, which contacts a second mounting surface of the unit support table, is formed on the rear flange part so as to face the front side thereof.

The main spindle unit has a main spindle, a front bearing, a rear bearing, a front case for covering the front bearing, and a rear case for covering the rear bearing. The front case has a front body part for holding the front bearing and a front flange part extending radially outward from the front body part. The rear case has a rear body part for holding the rear bearing and a rear flange part extending radially outward from the rear body part. A front mounted surface, which can be brought into contact with a first mounting surface of a unit support table, is formed on the front flange part so as to face the front side thereof. A rear mounted surface, which contacts a second mounting surface of the unit support table, is formed on the rear flange part so as to face the front side thereof.

A gear machining apparatus includes a rough working tool having a plurality of replaceable tool blades attached to a tool main body, such that the tool blades are arranged in a circumferential direction of the tool main body and blade tips of the tool blades are oriented outward in a radial direction of the tool main body, a finish working tool having a plurality of tool blades provided to a tool main body in a similar manner to the rough working tool, and machining controllers control to perform rough and finish machinings on the workpiece, such that the working tools are rotated on center lines in axial directions of the working tools, the workpiece is rotated on a center line in axial direction of the workpiece, and the working tools are relatively moved to the workpiece along the center line in the axial direction of the workpiece.

A gear machining apparatus includes a rough working tool having a plurality of replaceable tool blades attached to a tool main body, such that the tool blades are arranged in a circumferential direction of the tool main body and blade tips of the tool blades are oriented outward in a radial direction of the tool main body, a finish working tool having a plurality of tool blades provided to a tool main body in a similar manner to the rough working tool, and machining controllers control to perform rough and finish machinings on the workpiece, such that the working tools are rotated on center lines in axial directions of the working tools, the workpiece is rotated on a center line in axial direction of the workpiece, and the working tools are relatively moved to the workpiece along the center line in the axial direction of the workpiece.

A gear cutting tool configured to machine a workpiece with a skiving so as to generate a gear tooth includes a ring-shaped tool main body, and a plurality of tool blades which are replaceable and attached to the tool main body, such that the tool blades are arranged in a circumferential direction of the tool main body and a blade tip of each of the tool blades is oriented inward in a radial direction of the tool main body. Since the gear cutting tool for skiving is an internal gear type tool, the accuracy and the tool life of external gear machining when using the internal gear type tool are higher and longer than the accuracy and the tool life of external gear machining when using an external gear type tool. As a result, the frequency of replacement of the tool blades can be lowered and cost can be reduced.

The invention makes available a method for the production of gear wheels, with which it is possible to produce gear wheels having double-helical teeth, in particularly efficient manner. For this purpose, in the case of the method according to the invention for chipping production of a gear wheel, which is provided with double-helical teeth, in which the teeth of the one gear half are configured to run counter to the teeth of the other gear half, in rising manner, wherein the gear halves are arranged offset from one another by an angle amount with reference to the axis of rotation of the gear wheel, a gear wheel blank is made available, on which the teeth provided on the gear wheel are produced by means of hobbing, using a hobbing wheel, which, during hobbing machining of the teeth, in each instance, of one of the gear halves, reaches all the way into the adjacent tooth gaps of the other gear half, in each instance.