Micro electrode filament feeding guide mechanism for processing micro electric spark

Abstract

The invention belongs to the special micro-processing technical field and relates to a micro-wire electrode feed guiding mechanism used for micro-spark processing. The mechanism consists of an automatic compensation module for feed and loss of the micro-wire electrode, an auxiliary excitation module of the micro-wire electrode and a precision guiding module of the micro-wire electrode. A normally closed wire mechanism is positioned between the normally-opened wire mechanism and the precision guiding module, thus shortening the distance between wire points of the normally-closed wire mechanism and the guiding module and improving stability of the micro-wire electrode. The micro-wire electrode vibrates with high frequency under the auxiliary excitation module when carrying out servo feeding, which is used for improving gap discharge state and chip-removing conditions and enhancing the production efficiency. The precision guiding module can realize the guide with high precision to the micro-wire electrode by adopting a precision V-typed guide groove which is etched on the silicon. A standard V-type guide groove can adapt to the electrode wires in a certain range of diameter. The mechanism can be used for the micro hole machining.

Description

technical field [0001] The invention belongs to the technical field of special micro-machining, and relates to a micro-electrode wire feeding and guiding mechanism for micro-electric discharge machining. Background technique [0002] With the continuous development of micro-EDM technology, micro-hole EDM has made great progress in terms of precision improvement and size miniaturization. So far, the minimum diameter of micropores processed by EDM can reach several microns, the dimensional accuracy can reach micron level, and the surface roughness can reach submicron level. However, how to improve the machining efficiency of micro-holes and ensure the machining accuracy of micro-holes is still an urgent problem to be solved. [0003] In the process of micro-EDM, the compensation and precise guidance of micro-wire loss are one of the key issues. Although the method of online counter-copying electrodes can obtain extremely fine electrode wires and process extremely fine holes,...

AI Technical Summary

Problems solved by technology

However, when using a fine electrode wire, due to its poor rigidity, the distance between the clamping point of the wire clamping mechanism and the guide mechanism must be reduced, otherwise the fine electrode wire is prone to bending deformation, and its deformation will offset the servo of the electrode wire. Feed rate, which affects the stability of the machining process

At the same time, when the high-frequency excitation is added to the fine electrode wire, its bending deformation will offset the axial displacement of the electrode wire due to the high-frequency excitation, and the effect of additional high-frequency excitation cannot be achieved.

[0007] (2) If the normally closed wire clamping mechanism in the guide mechanism is above the normally open wire clamping mechanism, the fine electrode wire located between the normally closed wire clamping mechanism and the guiding mechanism is longer, and there are also fine electrode wires that are not rigid due to poor rigidity. problem with bending

With the reduction of the machining aperture, it is difficult for the fine electrode wire to pass through the guide tube smoothly

In order to ensure smooth wire threading, there is often a certain gap between the fine electrode wire and the inner wall of the guide tube, and the electrode wire is easy to deflect, which reduces the processing accuracy of the fine hole

[0009] In addition, when machining micro-holes with a high depth-to-diameter ratio, because the discharge pulse energy and the discharge gap are very small, the electrolytic corrosion products are not easy to be discharged from the processing area, and short circuits and arcing are prone to occur during the processing process, resulting in reduced processing stability and processing accuracy.

Images