Abstract: A machining technology based on error compensation by trial cuts was presented for improving machining precisions of a helical gear for CNC gear shaper. Firstly, the ideal main motion curve was derived using some straight lines approaching the ideal main motion curve, where the maximum allowable step of each straight lines and the corresponding crank angles that might satisfy the demands of machining precision were calculated. Then, the deviations of the main motion curve were calculated by the helix deviations of gear trial cuts, and a new more accuate ideal main motion curve was derived. At last, the new ideal main motion curve was approached by some straight lines again in the G codes used final gear machining. The test results show that the helix deviations of machined helical gears achieve 7 level accuracy, and satisfy the demands, and which verifies the feasibility of the method presented herein.

Key words: CNC gear shaper, electronic helical guide, helix deviation, main motion

摘要： 为了提高数控插齿机插削斜齿精度，提出了一种基于试切误差补偿的数控加工方法。首先，在分析斜齿螺旋线偏差产生机理的基础上，采用线段逼近理论主运动曲线，计算满足加工精度要求的线段最大许用步长和曲柄转角；然后，通过试切齿轮，测取螺旋线偏差并反求出主运动曲线偏差，获得更准确的新理论主运动曲线；最后，在生产用G代码中，重新用线段逼近新理论主运动曲线。实验结果表明：加工的斜齿轮螺旋线偏差达到7级精度，结果符合预期，验证了技术方案的可行性。

关键词: 数控插齿机, 电子螺旋导轨, 螺旋线偏差, 主运动