Precision Machining by Feedback of Shape Data (1st Report) -The Basic Concept and Examples of Corrective Machining-

Since industrial products have become higher in performance and finer in size, machining with higher accuracy is therefore a necessity. On one hand there is the requirement to machining with high accuracy and on the other there is the need to develop new systems to deal with this necd. In this paper, the authors propose a new concept of machining system with feedback of shape as in positioning with displacement feedback. To manufacture products with high accuracy, the authors have developed a simple and flexible method for an on-the-machine measurement system using calibration with geometrical solids. The authors have also developed a metal surface modification method using a green compact electrode of tungsten carbide powder by EDM in hydrocarbon oil. This process is realized on the same machine under the process of removal EDM and accretion EDM. These two techniques are combined in order to implement the precision machining system by feedback of shape data. Some examples of machining by this system are described. The machining accuracy of ± 20 μm can be achieved for both flat and 2-dimensional shapes by using the proposed system.