外螺纹滚压成形的多个滚丝轮的相位调整角的研究

Study on the phase adjustment angle of multiple thread rollers with external thread roll forming process

外螺纹滚压成形技术是一种先进无屑成形加工工艺,与车削加工相比具有生产效率高、成形零件机械性能好、节能节材等优点,广泛应用于汽车、航空航天、机床等工艺领域。随着螺纹和花键同步滚压成形、精密非标螺纹滚压成形等新工艺的发展,目前工业生产中常采用的滚丝轮牙位调整方法已不能满足发展需求。本文基于螺纹滚压成形过程中模具和工件螺纹啮合点的运动特征,推导出不同参数(成形工件头数nw、滚丝轮头数nd、滚丝轮个数N)下滚丝轮相位调整角的计算公式,提出了滚丝轮相位的调整方法:滚丝轮调整方向和布置顺序都与滚压成形过程中滚丝轮的旋转方向一致。针对不同工况设计了6组模具,通过绘制旋转剖视图观察到相位调整后的滚丝轮螺纹错开的距离与要求一致,使用FORGE软件进行仿真模拟得到了衔接良好的连续螺纹,因此验证了相位调整角数学计算公式和滚丝轮相位调整方法的正确性。为螺纹花键同步滚压成形和精密非标螺纹滚压成形等新工艺的研究提供了理论依据。

The external thread rolling technology is an advanced chipless forming process. Compared with turning process, it has the advantages of high production efficiency, good mechanical properties of formed parts, energy saving and materials, etc. It is widely used in automobiles, aerospace, machine tools, etc. With the development of new processes such as thread ＆ spline synchronous roll forming process and precision non-standard thread roll forming process, the adjustment method of the thread roller tooth position which is often used in industrial production has been unable to meet the development needs. In the text, on the basis of motion characteristics of the meshing point of the die and the workpiece thread during the thread roll forming process, the calculation method of phase adjustment angle of the thread roller under different parameters（head number of formed workpieces nw, head number of thread roller nd, number of thread roller N） has been derived. The adjusting method of the thread roller phase position has been put forward. The adjustment direction and the arrangement order of the thread roller are consistent with the rotation direction of the thread roller during the roll forming process. Six sets of dies have been designed for different working conditions. The distance between the phase-adjusted thread rollers has been observed to be consistent with the requirements by drawing the rotating sectional view. The FORGE software has been used to simulate and the continuous thread with good cohesion has been obtained. Thus in this way, the correctness of mathematical calculation formula of the phase position angle and the adjusting method of phase position of thread roller has been verified. It provides a theoretical basis for the research of new processes such as thread ＆ spline synchronous roll forming process and precision non-standard thread roll forming process.