Mechanical Structure Design And Optimization Of Intelligent Fixtures For Cantilever Workpiece Processing

With the continuous development of the solar thermal power generation business,Concentrating Solar Power technology has attracted more and more people’s attention.Among them,the efficient processing of the cantilever,one of the trough solar thermal power collector element brackets,has become particularly important.In mechanical processing,due to the large overall size of the cantilever,low rigidity,high processing accuracy,and large welding deformation in the previous process,it is difficult to install the workpiece,and the manual adjustment time is long,which is difficult to meet the requirements of mass production.The research group designed and developed a special equipment suitable for the processing of cantilever parts for the processing of large-size and low-rigidity cantilever parts.This thesis has conducted a key research on the intelligent fixture of this device,and the main work is as follows:(1)Based on the traditional workpiece clamping theory and the principle of active positioning technology,the principle model of cantilever positioning and clamping was established,and a special intelligent fixture for cantilever processing was designed.The three-dimensional model of each part was established with the help of SolidWorks software to complete the three-dimensional simulation assembly.(2)The method of combining theoretical calculation and simulation is used to analyze the stress of important parts in the fixture to determine that its stiffness meets the requirements of use.(3)Used the method of homogeneous coordinate transformation,the relationship between the error caused by the welding process and the position deviation of the workpiece is analyzed.Based on the knowledge of theoretical mechanics,the relationship between the local deformation and the overall position deviation is analyzed,and the model of the local deformation and the overall position deviation caused by the clamping force on the positioning surface of the workpiece is established.further modeling and analysis of the effect of the dynamic load on the part’s posture deviation during processing,using the Lagrangian energy method and Newton’s Euler formula to determine the part is under dynamic load The resulting pose deviation.With the help of Ansys finite element analysis software to analyze the workpiece positioning block,positioning block is analyzed to obtain the displacement cloud diagram of the upper surface of the workpiece positioning block under theclamping force,and it is determined that the fixture will not cause additional deformation to the workpiece during the work and meet the requirements of use.(4)Based on the finite element analysis of the structure of the fixture and the deformation of the workpiece,the intelligent fixture is optimized,the mathematical model for clamping optimization is established,the automatic fixture screw elevator and the fast rigid structure under the intelligent fixture are improved,and the intelligent fixture is optimized according to the clamping error Clamping sequence,to get the best fixture structure,so that the geometric error of the workpiece is minimized.Finally,the fixture has been practically applied on cantilever processing machine tools.The application results show that the fixture is stable and has fast automatic adjustment speed,which can meet the mass production needs of cantilever parts and greatly improve the manufacturing accuracy and efficiency of the cantilever.