Development of an integrated apparatus of micro-EDM and micro-CMM

Authors have developed a 4-axis micro-CMM that has miniaturized probe. By using an L-shaped probe, the micro-CMM can measure three dimensional coordinates of the high aspect ratio structures such as micro-holes. However, an installation error of the probe primarily affects the accuracy in the micro-CMM because the probe was previously machined in other micro-EDMs. In this research, we developed an integrated apparatus of micro-EDM and micro-CMM. The micro-EDM has 5-axis control with a general plate tool electrode and it can make probes of various shapes by the electric discharge scanning method. And the 4-axis micro-CMM has a mechanism that rotates the probe and it can measure with sub-micrometer accuracy. In this paper, Authors introduce a basic configuration of the integrated apparatus, machining method of the probe, and measuring method and measurement result of the micro-hole.

► Integrated apparatus of micro-5-axis EDM and 4-axis micro-CMM. ► Integrated EDM has 5-axis control with a general plate tool electrode for making probes of various shapes. ► Machining method based on shape generation functions for the probes of various shapes. ► The EDM is able to machine a L-shaped probe with an arm 170 μm long. ► Inner wall of the hole diameter of 300 μm is measured by the integrated apparatus.