The Design Of Rail Grinding Machine Servo System

With the speed increased largely, there has been a growing demand for rail smoothness. The rail’s qualities not only affect its own service life directly, but also influent passengers’ safety. At present, flash welding technology is used in rail welding, which makes formed along the welded joint during the process of upset forging. This convex plate must be removed for the purpose of meeting the requirements of rail smoothness. However, the hand polishing method of removing this convex plate is inefficient and poor quality. Therefore, it’s necessary of developing a special machine tool which can grind the welded joint effectively and automatically.The rail automatic fine grinding machine studied in this thesis is a kind of machine tool with characteristics of high quality, high efficiency, and automatically rail welded joint grinding. This machine tool can grind the rail surface in lm range centered in welded joint and the rail side, which meets the demand of smoothness.The machine tool in this thesis uses profile fitting grinding principle to grind rail welded joint, that is, grinding head driven by the rotatable support structure rotates around rail processing surface axis again and again in accordance with the designed rotation angle and gives a fitting grinding to the circular arc of rail surface.The paper mainly includes the following several contents:the overall scheme of rail grinding machine, the design of vertical servo system, the design of vertical servo control system, the design of vertical servo mechanism hydraulic system and its simulation. This paper combines the overall solution to vertical servo mechanism as the object of study. Vertical servo mechanism dynamic element is used in a closed loop Electro hydraulic Digital Servo cylinder, and detection of the electro hydraulic servo hydraulic cylinder displacement is adopted to pull type encoder。In the control system of the machine adopts programmable control system PLC, which is the choice of Siemens company production of the S7-200series of CPU224.It uses STEP7-Micro/WIN V4.0programming software in software design and trapezoidal chart language in programming so as to achieve the goal of maintaining and reading easily.