Pitch cone design and tooth contact analysis of intersected beveloid gears for marine transmission

• A pitch cone theory assuming line contact is derived for intersected beveloid gears.
• Axial position error has little influence on contact path and transmission error.
• Shaft angle error has detrimental effect on contact path and transmission error.
• Both FPD-angle and torque load have an obvious effect on mesh characteristics.
• The proposed model is validated by a practical loaded experiment.

A pitch cone based geometry design method considering line contact is proposed for intersected beveloid gears. The proposed pitch cone design applies the spatial gearing model to determine working pitch cone angles and working spiral angles. For the determination of geometry design parameters, a computer program which incorporates pitch cone design and line contact condition was developed. To illustrate the meshing characteristics, example studies with three groups of geometry parameters were performed by unloaded and loaded tooth contact analysis. Through the analysis, the influences of misalignments, torque load and angle between the first principal directions of the tooth surface curvatures (FPD-angle) on the mesh were investigated. The results show that: compared with axial position errors, shaft angle errors have a more detrimental influence on both the contact path and transmission error. Both FPD-angle and torque load have an obvious effect on this type of gearing. Finally, a practical experimental setup for intersected beveloid gearing with small shaft angle was performed and loaded tooth bearing tests were conducted to demonstrate the proposed design procedure and the theoretical simulation models. The experimental results compared well with the simulation.