Research And System Development For Gear Hobbing CNC Parameterized Automatic Programming

With the production pattern of gear manufacturing enterprises shift to more varietyand small batch production mode, market has a higher demand on production efficiency.The NC programming is an important factor to restrict the gear CNC productionefficiency, the traditional way of manual NC programming is big workload, lowefficiency and high error rate. The graphics interactive way of CAD/CAM automaticprogramming technology versatility is good, but need to be pre-built CAD model of theworkpiece, and the technical requirements of programmers. Hobbing CNC machiningthe workpiece structural characteristics and process characteristics is relatively fixed,the tool path and the cycle is relatively simple, the process is easy to implementparameterized. The process is easy to implement parametric. In this paper, theparametric generating NC machining program automatically programming technologyconducted in-depth research, and a NC automatic programming system for gear hobbingapplied in Siemens840D numerical control platform is developed.Specific research carried out in this paper are as follows: firstly, t based on theanalysis of user needs and he feasibility of hobbing parameterized automaticprogramming techniques, the system workflow and system architecture design wascompleted. Secondly, we study the classification method based on group technology ofgear, the gear workpiece classified according to the geometric characteristics andtechnological characteristics is similar of the gear, and to establish the the small taperbevel gear and cylindrical gear hobbing process mathematical model; Then, we studyparameters automatic programming method based on the standard template, accordingto the similarity of CNC hobbing code structure, abstract each type of gear unit hobbingNC code standard template, and use the expression driven algorithm to make standardtemplate instantiation, generate NC code automatically, realized the hobbing modular,parametric the NC program design; Finally, based on Siemens840D CNC system HMIsecondary development methods, research is mainly focused on the communicationbetween the HMI sequence control methods and OEM applications with CNC system.On the basis of the above study, NC automatic programming system for gearhobbing applied in Siemens840D numerical control platform is developed. Onlythrough man-machine interface to set specific processing parameters, hobbing NCprogram is generated Automatically. Application in a certain type of gear hobbing machine show that programming with high efficiency and reducing the cost ofproduction effectively, to ensure the gear machining accuracy and quality.