Fundamental Research on Hobbed Gear-tooth Surface Roughness : Influence of the Built-up Edge

Abstract

Poor surface finish commonly found on the gears used in the ashobbed condition often leads to a low surface durability. This paper presents detailed investigations about the effect and the formation of a built-up edge(BUE) which is one of the important factors influencing the surface roughness by performing hobbing experiments and simulated-hobbing tests. Moreover, the relation between the BUE and the cutting thickness which is dominated by the hobbing conditions is investigated. From the simulation tests, it is found that definite relationships exist among the size of the BUE formed on the cutting edge, the size of the cutting thickness and the surface roughness. Based on the results, it is clearly confirmed that these relationships are applicable to hobbing also.