The purpose of tool shifting of automobile gear hob is to make all teeth of hob have about the same wear degree, so as to increase the service life of hob. The position relationship of each hob tooth should be ensured during the tool shifting of automobile gear hob. As a result, the cutting times of most teeth of the whole hob are consistent. In the automobile gear hob, the teeth at each position have different cutting parts to remove material.
The service life of the tool after grinding can be prolonged by appropriate tool shifting. By establishing the allowable wear amount of automobile gear hob, after each grinding, the hob can process more parts with stable quality through a clear tool shifting procedure. If there is a reliable tool shifting procedure, the amount of material removed by each tooth of automobile gear hob should be the same. Therefore, the wear of all teeth of automobile gear hob is basically the same, and is far less than the excessive wear of hob caused by non-standard tool shifting procedure. In this way, the grinding amount of automobile gear hob can be reduced and the grinding times of automobile gear hob can be increased.