Study Of Machining Method Of Blower Vane With Discal Cutter

Axis flow blower blade is a type of free form surface part. Its surface shape and manufacture precision decide the blower's thrust efficiency and noises. The research about manufacture method will help to improve the manufacture precision and efficiency of this type of part. The traditional manufacture method of the axis flow blade is by rough cut with general milling machine plus a mass of manual polish. It is laborious and time-wasting and the precision can't be guaranteed. With the development of NC technology, at present, the machining of the axis flow blade is often finished by a NC machining with ball-end cutter usually. But the machining precision is not perfect yet. How to take full advantage of the potential of NC machining and how to mill the free form surface with discal cutter to improve the manufacture precision and efficiency of the axis flow blade have been the research emphases of NC machining. The problems are successfully settled by the method of discal cutter enveloping presented in paper.Geometry model and generation of cutter path are two key technologies for NC machining. In the two technologies, geometry model is the base for calculating cutter path and the accuracy of NC machining only depends on the rational cutter path. On the basis of the principle of the axis flow blade modeling and discal cutter envelope method, this thesis not only fits axis flow blade by cubic spline, but also analyses and contrasts the quality and efficiency of several usual NC milling schemes such as point-to-point mill, side-milling, spiral mill and so on; their advantage and disadvantage are pointed out at length, the algorithm of the seeking minimal orientation-distance is studied, the routine manufacture process is programmed, the mentioned above process is realized by C and the machining NC codes are generated.In this thesis the problem of low efficiency in blade's manufacture is solved based on NC scheme-Spiral machine. Geometry model by cubic spline is adopted, the technics process of spiral machine of blade on 4-axis milling machine and track-making algorithm during blade's spiral machine are designed in detail. And a new track with high quality is calculated. It also provides a good judge method of different NC mill scheme through description of manufacture routine and analysis of the NC manufacture technics. It is validated that the spiral machine is a favorable technical measure.