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

研究涉及一种新的加工概念，利用六轴控制。6-轴控制意味着切削工具允许用于定位的三个旋转运动以及三个平移运动。开发了一种六轴联动加工中心，在传统的五轴联动结构基础上，增加了一个可进行刀具定位的主轴。非旋转刀具安装在主轴上进行6轴控制加工，允许各种加工可能性。也就是说，使用非旋转刀具的6轴控制加工可以显示新加工技术的潜力。本文研究了两种新的加工技术：首先，开发了粗进给加工复杂曲面工件的控制软件，并进行了切削实验;结果表明，六轴联动加工可以实现良好的表面粗糙度。其次，本文研究了一种非旋转刀具非对称刻槽加工软件系统的开发。工具的形状与凹槽的横截面相同。非对称切槽是六轴联动加工的特点之一，它是三轴到五轴联动加工所不可能实现的。该系统包括两个阶段：第一是定义一个槽路径和一个槽形状与非对称的横截面，第二是粘贴在工件表面上的槽路径，并产生CL数据对应的槽形状，考虑过切和碰撞。生成的CL数据，然后转换为NC数据的6轴控制加工中心的后处理器。该软件系统验证了六轴非对称切槽加工的有效性。

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.