Approach for modeling elasticity in the gear honing process

The increasing requirements regarding load-carrying capacity and noise behavior have led to the use of case-hardened gears in high performance applications. In order to correct distortions from heat treatment and to meet the geometric requirements, case-hardened cylindrical gears are hard finished. For hard finishing, several high performance processes with undefined cutting edges are available. The dominating processes for cylindrical gears in the industrial application are gear honing, discontinuous profile gear grinding and continuous generating gear grinding. Gear honing is primarily used to hard finish small and medium sized gears with a module less than m(n) <= 5 mm. Due to the unique surface structure and the high economic efficiency in series production, gear honing is widely used in the automotive industry. The objective of previous investigations on gear honing was to analyze the efficiency of the honing process for gears with a module larger than m(n) > 4 mm. In some process setups, stability problems occurred due to excitation. The excitation leads to the conclusion that there is a lack of knowledge of the honing process, the honing machine and the process machine interaction. To meet this lack of knowledge, the gear honing process force was modeled. This process force model is based on a geometric penetration calculation. In the geometric penetration calculation, the tool-workpiece system is regarded as rigid. But in earlier investigations, it was shown, that the elasticity of tool and workpiece has an influence on the cutting process. Therefore, the objective of this report is to develop an approach for modeling the elasticity within the contact zone between the workpiece and the tool in the gear honing process using the finite element method. The complexity of the gear honing process was reduced by means of an analogy process. In the analogy process, the occurring process forces were measured and subsequently transferred to a finite element simulation. A force dependent deformation in the contact between tool and workpiece could be determined. Based on the force and the resulting elastically deformed volume, a constant characteristic value was calculated for the investigated area.