New Machining Methods by Means of 6-Axis Control Machining Center

研究了一种利用六轴联动控制的加工新概念。6轴控制意味着刀具允许三个旋转运动进行定位，以及三个平移运动。研制了一种六轴联动加工中心，在传统的五轴联动控制结构的基础上，增加了一台可实现刀具定位的主轴。在主轴上安装非旋转刀具，进行6轴控制加工，允许多种加工可能性。也就是说，用非回转刀具进行六轴联动加工可以显示出新加工技术的潜力。本文研究了两种新的加工技术。首先，结合加工实验，开发了一套加工复杂曲面零件的控制软件。研究结果表明，六轴联动加工具有良好的加工表面粗糙度的可能性。其次，开发了一种非回转刀具在复杂曲面上进行非对称刻槽的软件系统。刀具的形状与凹槽的横截面相同。不对称刻槽是六轴联动加工的特点之一，不对称刻槽是3-5轴联动加工所不具备的。该系统包括两个阶段：第一阶段是定义一个非对称截面的凹槽路径和凹槽形状，第二个阶段是将凹槽路径粘贴在工件表面上，并考虑过切和碰撞，生成与凹槽形状相对应的CL数据。生成的CL数据然后由后处理器转换为用于6轴控制加工中心的NC数据。该软件系统验证了六轴非对称开槽的有效性。

The study deals with a new machining concept by making use of 6-axis control. 6-axis control implies that a cutting tool allows three rotational movements for positioning as well as three translational ones. A 6-axis control machining center equipped with a main spindle capable of tool orientation in addition to conventional 5-axis control structure is developed. A non-rotational cutting tool is mounted at the main spindle to carry out 6-axis contorl machining, which allows a variety of machining possibilities. Namely, 6-axis control machining with a non-rotational cutting tool can show the potential of new machining technology. Two kinds of new machining technologies are investigated in the study.At first, a control software to finish workpieces with sculptured surface in the coarse pickfeed is presented together with cuting experiments. As a result, it is found that 6-axis control machining reveals the possibility of finishing with good surface roughness.Secondly, the study deals with the development of a software system for asymmetrical grooving on a sculptured surface by use of a non-rotational cutting tool. The shape of the tool is the same as the cross section of the groove. Asymmetrical grooving, which is improssible to machine with 3-to 5-axis control, is one of the characteristic features of 6-axis control machining. The system consists of two stages : the first is to define a groove path and a groove shape with an asymmetrical cross section, the second is to paste the groove path together on the workpiece surface and to generate CL data corresponding to the groove shape, taking account of overcutting and collisions. Generated CL data are then converted to NC data for a 6-axis control machining center by the postprocessor. This software system shows the validity of 6-axis asymmetrical grooving.