Gear machining apparatus and machining condition determination device

1. A gear machining apparatus comprising:

a hob cutter configured to machine a gear profile on a workpiece;

at least one processor; and

at least one memory having instructions that, when executed by the at least one processor, cause the gear machining apparatus to perform operations to relatively move the hob cutter and the workpiece while synchronously rotating the hob cutter and the workpiece,

wherein the operations comprise:

performing first chamfering on a first axial end of the gear profile by relatively moving the hob cutter with respect to the workpiece in a radial direction of the workpiece while relatively moving the hob cutter with respect to the workpiece in an axial direction of the workpiece;

performing, subsequent to the first chamfering, gear profile machining by relatively moving the hob cutter with respect to the workpiece in the axial direction of the workpiece; and

performing, subsequent to the gear profile machining, second chamfering on a second axial end of the gear profile opposite to the first axial end in the axial direction by relatively moving the hob cutter with respect to the workpiece in the radial direction of the workpiece while relatively moving the hob cutter with respect to the workpiece in the axial direction of the workpiece.

2. The gear machining apparatus according to claim 1 ,

wherein in the first chamfering, the hob cutter is relatively moved with respect to the workpiece in a first relative movement direction forming a first angle with respect to a central axis of the workpiece,

wherein in the second chamfering, the hob cutter is relatively moved with respect to the workpiece in a second relative movement direction forming a second angle with respect to a central axis of the workpiece,

wherein the first angle is set to be different from a first chamfer angle at the first axial end of the gear profile, and

wherein the second angle is set to be different from a second chamfer angle at the second axial end of the gear profile.

3. The gear machining apparatus according to claim 1 ,

wherein the operations further comprise:

performing, in relation to each of the first chamfering and the second chamfering, simulation of a chamfered shape with respect to a plurality of types of machining conditions related to a relative movement trajectory of the hob cutter with respect to the workpiece; and

determining one machining condition related to the relative movement trajectory of the hob cutter with respect to the workpiece such that the chamfered shape satisfies an allowable condition, and

wherein each of the first chamfering and the second chamfering is performed based on the one machining condition.

4. The gear machining apparatus according to claim 3 ,

wherein the machining condition in the first chamfering comprises: a first angle indicating a direction of a first relative movement of the hob cutter with respect to the workpiece; and a first end position of the first relative movement at the first angle, and

wherein the machining condition in the second chamfering comprises: a second angle indicating a direction of a second relative movement of the hob cutter with respect to the workpiece; and an second end position of the relative movement at the second angle.

5. The gear machining apparatus according to claim 3 ,

wherein an element of the chamfered shape comprises at least one of:

a first chamfer angle at a first corner of a tooth top of the gear profile, the first corner being defined by an end edge in the axial direction and an end edge in a tooth thickness direction;

a first axial chamfer length at the first corner;

a second chamfer angle at a second corner in an axial cross section of the workpiece, the second corner being defined by a tooth root and an axial end face of the gear profile; and

a second axial chamfer length at the second corner.