The Development Of Control System For Five-coordinate Water Cutting Machine

High-pressure waterjet cutting is a kind of cold processing technology developed in the 70 ’s,because it has many characteristics and advantages,it has been developed very rapidly in the last 30 years,and is widely used in aero-engine manufacture.With the development of aerospace engine,more and more special materials are used,the requirements of the process are more and more complicated,and the function of the water cutting machine is higher.Aiming at realizing the localization of the control system of the five-coordinate water cutting machine,this paper develops the control system of the five-coordinate water cutting machine tool,through analyzing the function demand of the machine tool,puts forward the overall plan of the control system development.On this basis,the device selection of each system is completed,the electrical connection of each system is designed,the control system is programmed,the function of the machine is validated by experiments,and the localization of the control system of the water cutting machine is realized.Firstly,the whole structure of the water cutting equipment is analyzed,and the overall scheme of the electrical and control system is clarified.Aiming at the problem of unable to store the location in the process of the water cutting machine,the paper puts forward the positioning scheme which can store and adjust the locating point at any time.The selection of each system components is completed,the working principle of the booster unit is analyzed in detail,and the dynamic characteristics of the high-pressure system and the calculation of high-pressure water flow are analyzed theoretically,which provides theoretical basis for the design of electric control system.Then,the whole electric composition scheme and circuit design of the machine tool are studied,the main circuit of the machine tool,the emergency stop auxiliary circuit,the I/O module control circuit and the four main electric parts of the servo shaft drive circuit are designed.With the control unit as the core,the interface is used to connect with the peripheral,which is helpful to expand the function and replace the equipment.In order to ensure the stability of each system,increase the reactance element to resist electromagnetic interference,PLC uses Low-voltage circuit,the circuit uses 24 V voltage-stabilized power supply.An integrated circuit is used to control the output,reduce the EMI and save the circuit line loss.On the basis of completing the electrical connection of each part,this paper analyzes the three-ring principle of servo control(closed-loop,semi-closed loop,open-loop),calculates and analyses the principle of some servo parameters,and obtains the intrinsic frequency,overshoot,adjustment time and damping coefficient of the important parameters affecting the gain system.On the basis of the optimization of the servo system parameters,the system achieves the optimal working state.On the basis of the hardware design and connection of the electrical control system,the software part of the control system is programmed in this paper.Firstly,the paper analyzes the file structure of NC system,and compiles the parameter file of NC system.The function of the control system is analyzed,the PLC file of the NC system is compiled,and the control of the function of the system is realized.Finally,the accuracy of the feed shaft is tested by Laser interferometer,and the location error of each axle is compensated by the parameter configuration file of the control system,and the positioning accuracy is not 0.110 mm,the repeatability positioning accuracy is not more than 0.070 mm,and the precision machining needs are satisfied.Through the actual liner parts processing,using the three coordinate measuring machine to detect the hole,through the analysis of the position data,verify that the processing capacity of the equipment fully meet the design requirements,the qualified rate of 92.9,meeting the technical requirements and realizing the localization targets of five-coordinate water cutting machine control system.