Gear rough hob is mainly used before fine rolling. They are mainly used to process large module gears, with a very large amount of metal cutting. In order to improve the efficiency in actual production, two gear hobs are usually processed at the same time.
The type and size of gear rough hob, including aperture, standard tooth profile and segmented displacement combination system.
Gear double head rough hob is generally used for rough machining. Dual threading can achieve more efficient processing. The gear hob can also control the machining allowance in a certain accuracy to ensure the lowest tool machining cost. Ensure that the position of the two main teeth of the gear parts is consistent. Gear hobs usually have two heads and a rake angle of about 5 °. However, sometimes more than two heads are used, which mainly depends on the level of equipment. Gear hobs with diameter pitch above 4 are generally single head.
The development of gear rough hob provides important tools for a large number of gear rough machining. Because the pitch diameter of the generated gear is smaller than that of the standard gear, they are sometimes called “low tooth” hobs. The teeth of gear hobs are suitable for high cutting efficiency and longer service life. They are usually designed with straight teeth, 8 ° front feet and double heads. Of course, some other special requirements can also be added.
In addition, due to rough machining, the pitch diameter and basic tooth thickness of gear hob can be increased by changing positions, so as to increase the service life of gear hob.