A CNC machining method for arc end teeth based on machining accuracy index calibration

Mon Aug 01 14:56:32 CST 2022

A method for NC machining of circular arc end teeth based on machining accuracy index calibration, which is characterized by comprising the following steps: Step 1: Solving the theoretical meshing parameters of full-scale circular arc end teeth First, the number of teeth enclosed by the rotation of the tooth surface center For the most principle, simulate the digital information of the three-dimensional solid shape of the tooth surface rotating body and the part intersecting and the difference of the tooth shape, and optimize the adjustment of the tooth surface rotation center position and radius value data; then, initially determine the circular arc end teeth. The rotation center position and radius value of the tooth surface are obtained, and the curve and solid simulation of these structures are used to analyze the rotation center position and radius value of the tooth surface of the arc end tooth for solution and feature extraction; finally, the optimized and adjusted tooth surface rotation center position and The radius value is used to construct the tooth surface entity, solve the shape parameters, and calculate the geometric information of these corresponding points, and finally preprocess the tooth surface rotation center position and radius value; The specific solution process is as follows: (1) Initially determine the pitch circle position and radius r of the tooth surface: First, the radius of the tooth center of the arc end of the part is known to be R, and the rotation center of the tooth surface of the arc end tooth and the center of the part are set on the same line On the straight line, assume R≈r, L=1.4R, where L is the center distance between the pitch circle at the arc end of the part and the pitch circle of the tooth surface; then, the position of the rotation center of the tooth surface is initially determined; (2), the tooth surface Determination of pitch circle radius: set the number of teeth as n, roughly calculate according to the distribution of equal tooth thickness, the tooth length on the pitch circle at the arc end of the part is the circumference/2n; set the concave tooth element A/a=1.3~1.4 or convex Tooth element A/a=1.2~1.3, roughly determine the coordinate points 1 and 2 on the pitch circle of the tooth surface, adjust the center of the pitch circle of the tooth surface according to the positions of the coordinate points 1 and 2, and determine the exact coordinate position of the pitch circle of the tooth surface ;According to the coordinate position of the tooth surface pitch circle center, correct the tooth surface pitch circle radius value to determine the accurate tooth surface pitch circle radius;

Step 2: Directly generate CNC machining tool path based on simulation analysis and calibration of machining accuracy and cutting amount. First, the preprocessed tooth surface rotation center position and radius value are used as control points to construct a parameterized arc end tooth surface; then , divide the constructed circular arc end tooth surface surface into different processing areas; finally, use the "simulation analysis to calibrate the machining accuracy and cutting amount to directly generate the NC machining tool path" processing measures to generate rough and finishing tool paths; Each processing area is processed independently, that is, the processing of the entire surface is to process all processing areas independently; determine the residual height: H=DC/2‑SQUARE(DC2‑ae2)/2, DW=2SQUARE( ap(DC-ap)), H-remaining height, Dc-tool diameter, ae-cutting width, Dw-working diameter, ap-cutting depth; determine the amount of material removed: the calculation formula is as follows: ΔP = HR - H 1 - ( H 2 - H 3 ) / 2 3 where, ΔP-cutting amount, HR-achieved measurement height, H1-standard part pitch circle height, H2-arc end tooth base reference to tooth top face height, H3-tooth Top to pitch circle height.