Hob mill profiling method for generation of timing belt pulley

In this paper is proposed an algorithm based on the complementary method of surface en wrapping the method of generating relative trajectories for profiling hob mill designed for machining of timing belt pulleys, with circle frontal profile. A profiling algorithm for hob mill is proposed. The algorithm is developed in analytical form and is compared with a graphical method developed in CATIA design environment for a real example. The algorithm starts with analytical equations determination of profile to be generated. For this profile is determined the family of trajectories described in the relative motion between tool and blank. The family of normal’s to these trajectories is determined and is selected the normal which pass through the gearing pole. The point corresponding to this normal belongs to the characteristic curve, so it will belong to the tool’s surface too. In this way, the profile of intermediary surface is determined. The intermediary surface is an auxiliary surface which represents the surface of rack gear tool generating the desired profile. Consequently, knowing the form of the generating rack gear, the profile of hob mill is determined. For this, a helical motion is applied to the rack gear’s profile. The axial form of hob mill is presented as base for generation of this tool’s type. © Springer International Publishing AG 2017.