Orthogonal-Surface Gear Tooth Milling Processing and Measurement Analysis Research

To validate the feasibility of milling orthogonal-surface gears (surface gears), the tooth surface equation was derived based on the envelope method and gear meshing principles. Building upon this, a tooth surface parametric model and 3D solid model were established. Combining the kinematics of a five-axis CNC machine, tooth surface toolpath planning and CNC program generation were completed. A five-axis ball-end mill milling test was conducted on a three-tooth gear specimen. Subsequently, the tooth surface point cloud data was acquired using MetraSCAN 3D optical scanning. Quantitative evaluation of the machined tooth surface was performed through point cloud registration and deviation calculation. Results indicate that machining errors primarily concentrate in the crown and root regions, with relatively minor deviations in the mid-section. Key factors contributing to excessive crown/root errors include tool posture constraints in confined spaces, abrupt local cutting condition changes, and insufficient path continuity in transition zones. To address these issues, this study proposes adopting segmented constant residual height/constant chord height strategies in root transition zones, optimizing tool axis inclination and feed rates, and integrating tool radius compensation with machine geometric error calibration to enhance forming accuracy in both crown and root regions. This research provides reference for five-axis milling and measurement evaluation of orthogonal-surface gear tooth surfaces.