A Study on Numerically Controlled Machine Tools for Cutting Noncircular Gears and Their Control Method

近年来，人们逐渐认识到非圆齿轮的用途，对非圆齿轮的需求也在迅速增加。然而，传统的设计和制造方法无法满足非圆齿轮的生产需求。因此，非圆齿轮的生产制造系统已被强烈要求。为了提高非圆齿轮加工的生产率和精度，研究人员试图提高数控齿轮加工机床的性能。此外，由于CAD / CAM系统对提高非圆齿轮的生产率也起着非常重要的作用，因此开发了一种新的非圆齿轮CAD / CAM系统。本文的研究成果总结如下：首先，将插齿机和滚齿机改造成能够精确切削非圆齿轮的数控齿轮加工机床。其次，作为非圆齿轮的应用，提出了一种蜗轮旋转误差补偿机构，并对其进行了验证。此外，利用研究人员开发的CAD系统，可以方便地设计和生产用于补偿的非圆齿轮。利用傅里叶变换推导出它们的间距曲线。这种利用傅里叶变换的设计方法对于非均匀运动机构的设计是非常有用的，因为该方法所设计的俯仰曲线保证了驱动和从动器的俯仰曲线都是闭合形式。采用这种设计方法的CAD系统与采用经验设计方法的系统相比较，使我们能够非常有效地设计非圆齿轮。此外，作为非圆齿轮的另一个应用，提出了一种新的车辆转向机构。分析结果表明，转向机构的非圆齿轮为椭圆齿轮。由于该转向机构能使车辆以很小的半径转向，且椭圆齿轮适于生产，因此可以预见该机构将用于多种车辆的转向系统。少

Recently, usefulness of noncircular gears has been recognized and the demand of them is rapidly increasing. However, the conventional design and manufacturing method have no capability of production of the noncircular gears as much as the demand. Therefore, the productive manufacturing system for noncircular gears has been strongly desired. In order to improve the productivity and accuracy of the noncircular gears, the investigators tried to increase the performance of NC gear manufacturing machines. In addition, since CAD / CAM system also plays very important roll for improvement of the productivity, a new CAD / CAM system for noncircular gears were developed.The summary of this research results are as follows : First, we converted a gear shaper and a hobbing machine into NC gear manufacturing machines which can precisely cut noncircular gears. Secondly, as an application for noncircular gears, an compensation mechanism for rotational error of worm gear was proposed and it was proved … More by using the CAD system developed by the investigators that the noncircultar gears for compensation can be easily designed and produced. The ptich curves of them were deduced from Fourier transform. This design method using Fourier Transform is very useful for design of non-uniform motion mechanism because the pitch curves designed by this method are assured that both pitch curves of the driver and follower always have closed form. The CAD system including this design method enables us to design the noncircular gears very effectively in comparison with the system using empirical design methods. In additon, as the other application of noncircular gears, a new steering mechanism for vehicles was proposed. From the result of analysis, it became clear that the noncircular gears for the steering mechanism are elliptical gears. Since the steering mechanism enables the vehicle to turn with a very small radius and the elliptical gears are suitable for productin, we can anticipate that this mechanism will be used for steering system of many kinds of vehicles. Less