Technology And Special Machine Research Of Electrochemical Deburring In Internal Crossed Array Holes

By observing the turning screw shaft parts structure of the vehicle hydraulic power steering system, there are multiple array holes in its circumferential direction. The diameter range of the holes is 2-4 mm. At the time the holes are drilled, array hole burrs are produced in intersecting position of the inner hollow cavity. The height of the burrs is 0.2-2 mm, and the thickness is 0.2-0.5 mm. As the holes are not easily reached and the burrs are in different sizes, it is difficult to completely deburr for general processing method. The processing method of the electrochemical deburring is very suitable for the inner cavity deburring of complex parts. There is no mechanical force in the processing. And it is high machining efficiency, high machining accuracy and surface quality and easy to realize automation. So it is widely used in hydraulics and pneumatics parts, aerospace and other processing industries.According to the burr characteristics of the internal crossed array holes, the electrochemical deburring processing method of array electrode is adopted, the technological law of the deburring processing and the electric field and flow field of the processing gap is researched based on electrochemical theory. According to the similar characteristics of each hole, one of the holes is selected for establishing the mathematical model of the deburring processing. The mathematical model is simulated through the finite element software of COMSOL Multiphysics. The influence rules of various processing parameters on the processing are obtained.A special electrochemical processing machine tool for array holes deburring is developed. Based on the analysis of the functions and characteristics of the machine tool, the overall layout of the whole machine is determined. The mechanical system, the hydraulic system and the electrical system are designed and developed, the final manufacture and assembly of the machine tool is completed. The work fixture is designed for the particularity of cross array holes. For the safety of the machine, the security detection circuit is designed to avoid electric shock and the short-circuit detect circuit between the poles is designed to avoid short circuit so that it will damage the power or burn the workpiece and the electrode.According to the simulation results, the reasonable of the processing parameters is determined. The internal crossed array hole burrs of the turning screw shaft is deburred with the developed machine tool. The changing law of the processing parameters is found. According to the changing law of the electric current in the processing, the automatic control system will be designed. The processing experiment is executed to verify the feasibility and practicability of the automatic control system.