There are generally two ways to install and drive automobile gear hobs. Automotive gear hobs are usually mounted on a smooth mandrel or hob shank. The automobile gear hob must have a large enough diameter to ensure that the hob clamping adopts a closed structure. Sometimes when working conditions such as diameter pitch and groove depth do not allow the use of large aperture hobs, only conical aperture hobs can be used. For example, small diameter worm gear hob must ignore the characteristics of part structure.
The hole diameter of automobile gear hole hob can be made into straight or conical hole. The selection of straight hole or conical hole is mainly based on the diameter, modulus and equipment of the parts processed by hob. The diameter of the keyway can be adjusted by using the straight keyway or the keyway. Generally, there is no requirement for the keyway of small diameter and small module gears.
Now some tool manufacturers have developed taper hobs with keyways. The purpose of taper hole hob is to reduce the gap between hob shank and hob aperture. Compared with the straight hole hob, the taper hole hob can also ensure that the hob clearance is within the minimum range without a lot of adjustment. Generally, the diameter of taper hole hob is much larger than that of straight hole hob.
Because the straight hole hob can be installed end-to-end, it can rotate and cut clockwise or counterclockwise. However, for the taper hole hob, it must be installed correctly before it can be used, which mainly depends on the model of processing equipment, the correct processing method and the cutter bar of automobile gear hob.