Abstract: A new principle here named orthogonal link-movement technology is proposed. Based on the technology, an arbitrary gear tooth profile can be generated on a CNC(Computer numerical controlling) hobbing machine tool by means of a standard involute gear hob. Computer simulation is done for gear tooth tip relief, and the results show that the new principle is right and practicable. So the restriction of traditional method in which different gear tooth profiles must require adaptive and different cutting tools is broken by the new method. This is of momentous economic and current significance for economizing expenditure.

Key words: Addentum modification, Arbitrary gear tooth profile, Orthogonal link-movement technology, Standard involute hob