“Gear manufacturing manual” and other data on the cutting parameters of spiral bevel gears are aimed at the traditional mechanical gear milling machine. CNC spiral bevel gear milling machine is more and more widely used in production. One of the accompanying problems is the lack of a cutting parameter selection method suitable for CNC spiral bevel gear milling machine. In production practice, the cutting parameters are often selected according to the existing content and practical experience, which makes it difficult for the NC gear milling machine to give full play to its best production efficiency. Compared with the traditional mechanical gear milling machine, the CNC spiral bevel gear milling machine has many advantages, which are mainly reflected in: high stiffness, stepless speed change can be realized by cutter head rotation and linkage shaft movement, and high indexing accuracy and repeated positioning accuracy of workpiece shaft. These advantages of NC gear milling machine make it possible to optimize its cutting parameters.
Firstly, the principle of harmony search algorithm is introduced, and then the cutting parameter optimization in the machining process of cutting spiral bevel gear big wheel by forming method and rough milling spiral bevel gear small wheel by hobbing method is studied:
(1) Aiming at the rough machining of spiral bevel gear by forming method of yk2180r gear milling machine, an optimization model is established, which takes the shortest process time of a single piece as the objective function, the maximum allowable cutting speed of the blade, cutting power and tool durability as the constraints, and the cutter head speed and the feed speed of the sliding table of the workpiece box as the optimization variables. The optimization program is compiled by MATLAB to optimize the cutting parameters of forming method;
(2) Aiming at the machining process of rough milling spiral bevel gear small wheel by hobbing method of yk2260m four axis NC gear milling machine, taking the shortest process time (maximum productivity) and the lowest machining cost of a single piece as the objective function, taking the allowable maximum cutting speed, cutting power and tool durability of the blade as the constraints, and taking the cutting speed, linkage shaft moving speed and single-step interpolation angle as the optimization variables, A multi-objective optimization model of cutting parameters for rough milling spiral bevel gears by NC Hobbing method is established. The optimization program is written in MATLAB to obtain the best rough milling cutting parameters, and the effectiveness of the model is verified by a specific example.