In the case of TV products, space constraints and design requirements make it advantageous to use a worm gear that has a small volume and a self-locking function. Single enveloping worm gear teeth are classified as ZA, ZN, ZK, ZI, and ZC according to international standards. However, combining worm shafts and worm wheels with different tooth profiles can significantly worsen meshing transmission errors and reduce the lifespan of the worm gear. Despite these challenges, due to processing limitations, ease of manufacturing, and cost reduction, combinations of worm shafts and worm wheels with different tooth profiles are still considered. In this study, we confirmed the meshing transmission error for a worm gear that combined a ZA tooth shape worm shaft with a ZI tooth shape worm wheel. Additionally, we examined the contact stress and fatigue life characteristics of the material combinations using finite element analysis (FEM).

When a workpiece contains complex burr edges from a combination of drilling and milling, conventional deburring tools such as wire brushes may not be effective in their removal. In this study, abrasive flow machining was used to gain access to complex burr edges. Experiments on two types of flow guides suggest that an abrupt change in direction of flow around the area with targeted burr edges is essential. The effects of several process parameters are investigated based on the experiments set up.