A Top-down Design Method For Static Stiffness Of Moving Column Precision Horizontal Machining Center

The structure scheme design of machine tool needs to satisfy the accuracy of the work piece.The static characteristic of precision horizontal machining center has a significant impact on the machining accuracy.In the early design phase,to design the overall structure of the whole machine by the user's processing requirement,which is of great significance to improve the quality and efficiency of machine tool structure design.Therefore,taking dynamic column precision horizontal machining center for research objects,related work which include the static stiffness modeling and static stiffness matching design were carried out,and established the scheme database of structure,and develop a top-down design software for the user's static stiffness matching design and calculation and inquires,which improve the efficiency of the machine designers.The main work and conclusion are as follows:Firstly,based on the theory of multi-body system,the function relation between the deformation of machine tool parts and the end of the whole machine is established.And the function relation between the deformation of the machine tool and the static stiffness of the structure is established by the mechanical analysis of the machine tool structure.Introduce the concept of static stiffness coefficient of the specific location of the deformation as the structure of the static stiffness value,then its simultaneous as intermediate variables of these two functions,and then establish the model of static stiffness of the machine.Finally,the accuracy is verified by static stiffness test of the whole machine.Secondly,the contribution of each component to the static stiffness of the whole machine is obtained by the method of experimental design,which will be the design target of the static stiffness matching.Combined with the range of the machine tool parts and the NSGA-II optimization design method,the static stiffness of each component is matched by the value of the end stiffness of the whole machine.Finally,the feasibility is verified by finite element simulation analysis.Again,the optimal structure size parameters can be obtained by the optimization goal of the structure static stiffness and the multi-objective optimization algorithm and CAD/CAE integration method.Then,by changing the static stiffness value of the target,the structure dimension database of static stiffness of the structure can be obtained.Finally,the static stiffness of the machine design software aimed at the moving column horizontal machining center which is faced to the user is completed based on the above technology and methods,which realize the matching design and structure of the static stiffness of the structure size of query function,the calculation of the static stiffness of the structure,and this greatly improves the design efficiency of machine tool structure design.