空间圆弧逼近法加工螺旋曲面的参数优化

螺旋机械的核心部件——螺杆转子的螺旋曲面成形复杂、加工难度大，国内外较多采用成形车削方法加工，此法在加工精度、加工效率及螺杆表面质量上存在不足，为了获得更好的螺旋表面加工质量，提出了外切圆弧母线逼近加工方法.依据圆弧逼近原理，建立了螺杆转子空间螺旋曲面的铣削模型，确定了刀具空间逼近圆弧的基本结构参数，求解了逼近圆弧的加工误差，实现了刀具逼近圆弧参数的优化设计，并给出了相应的计算实例.计算结果表明，提出的刀具参数优化方法具有可行性.

Optimal design of tool parameters for machining helical surface according to spatial arc approach method

The forming for the helical surface of screw-rotor as key part of screw machine is complicated,and has the greater machining difficulty.Form turning method usually used at home and abroad is insufficient in precision,machining efficiency and surface quality.Thus,a new exterior arc-generatrix approach method is put forward to acquire satisfied surface quality.According to the approaching theory of spatial arc,the milling model of spatial helical surface of screw rotor was established,and the basic parameters of spatial approach arc of cutter were determined.The machining error of the approach arc was resolved,the optimum design of tool approach-arc parameters was finished,and the calculated example was given.The calculated results show that the proposed optimization method of tool parameters is of feasibility.