Tooth surface deviation and mesh analysis of beveloid gears with parallel axis considering machine tool adjustment errors

摘要

The mathematical beveloid gear tooth surface model considering machine tool adjustment errors was derived. The definition and calculation process of tooth surface deviations along the tooth trace and profile directions for beveloid gear were proposed. Also, the solid model and the finite element mesh model of a paralleled beveloid gear pair were developed. Then, the effects of the machine tool adjustment errors including independent helix angle error, independent cone angle error and combined helix and cone angle errors on tooth surface deviation and contact characteristics were investigated. Results show that all the machine tool adjustment errors cause an incremental trend for the tooth profile and tooth trace deviations. And positive errors have the opposite impact on the surface deviation compared with the negative errors. The independent helix angle error has a stronger impact on the tooth surface deviations than the independent cone angle error and combined angle errors. Also, the tooth surface deviations caused by the independent helix angle error, independent cone angle error and combined angle errors have the similar magnitude level as the tooth surface modifications. All the independent helix angle error, independent cone angle error and combined angle errors tend to have deteriorative effects on the mesh characteristics, making edge contact worse, decreasing the contact area, increasing the contact pressure and the transmission error. The independent helix angle error has the strongest impact both on the contact pattern and transmission error, which is similar to the impact on the tooth surface deviations. However, the independent cone angle error shows less effects on the mesh characteristics. Thus the machine tool adjustment errors should be strictly controlled especially for the helix angle error during manufacturing.