Analysis of the Tooth Surface Contact Area of a Circular-Arc-Tooth-Trace Cylindrical Gear under Load

To reconstruct the tooth surface of a circular-arc-tooth-trace cylindrical gear (CATT cylindrical gear), a 3D model has been developed and the contact characteristics have been investigated.Based on the development principle and meshing theory, the tooth surface equation, tooth surface curvature equation and tooth surface contact ellipse equation of the CATT cylindrical gear were deduced, and it was proved that the contact was a point contact.Then, the tooth surface was reconstructed and a 3D model was developed.Next, by performing the finite element analysis and meshing impression experiment, it was proved again that the contact is the point contact, and the contact area became an ellipse under loading.Finally, the influences of the design parameters on the contact ellipse were investigated.The general tendency is that the elliptical contact area increases from the tooth root to the gear top; the elliptical contact area decreases when the modulus and the gear tooth number near the tooth root increase and it increases when the modulus and the gear tooth number near the tooth top increase; the elliptical contact area increases when the tooth line radius increases.The elliptical contact area decreases in a cliff-like manner near the tooth top.The research results provide a reference for the design, profile modification and lubrication of the CATT cylindrical gear.