A toothed workpiece chamfering device having a chamfering head (2) which includes a first axis of rotation (B) for rotation of a first chamfering tool (6) and a second axis of rotation (T) for rotation of a second chamfering tool (8) wherein the first and second chamfering tools are of different types and their respective material removal methods are also different from one another. Preferably, the first and second axes of rotation are not coincident with one another and in a more preferred arrangement, the first tool axis and the second tool axis are arranged perpendicularly to one another.

A toothed workpiece chamfering device having a chamfering head (2) which includes a first axis of rotation (B) for rotation of a first chamfering tool (6) and a second axis of rotation (T) for rotation of a second chamfering tool (8) wherein the first and second chamfering tools are of different types and their respective material removal methods are also different from one another. Preferably, the first and second axes of rotation are not coincident with one another and in a more preferred arrangement, the first tool axis and the second tool axis are arranged perpendicularly to one another.

A worm reduction gear satisfies following relational Formula (1) and Formula (2):
3D2/D11.7(1)
0.10.5(2)
where D1 is an outside diameter of a worm, D2 is an outside diameter of a hob for cutting a worm wheel to form tooth spaces, and is a pressure angle of the worm wheel and is a pressure angle of the worm at an intermeshing pitch circle of the worm and the worm wheel.

A worm reduction gear satisfies following relational Formula (1) and Formula (2):
3D2/D11.7(1)
0.10.5(2)
where D1 is an outside diameter of a worm, D2 is an outside diameter of a hob for cutting a worm wheel to form tooth spaces, and is a pressure angle of the worm wheel and is a pressure angle of the worm at an intermeshing pitch circle of the worm and the worm wheel.