Research On Key Technology Of Error Control In Assembly Of Precision Horizontal Machining Center

As a key process of machine tool manufacturing,assembly has a great impact on the final performance of the machine tools.This paper focuses on the related engineering requirements of key technologies for precision horizontal machining center assembly,the relevant theory and method of assembly error propagation and control is studied.The research was used to guide the assembly of a typical precision horizontal machining center and realized its geometric error adjustment and control.The main work is as follows:Based on the kinematic theory and homogeneous coordinate transformation,consider the manufacturing error and assembly deformation,the error propagation between two adjacent parts is analyzed and the error accumulation model along assembly process is built.The accumulated error in every assembly station of the key characteristics can be predicated with this model,providing a theoretical basis for the assembly accuracy predication and control.The finite element model of the precision horizontal machining center consistent with the assembly process is built in AQAQUS software,the model takes the assembly position and orientation of the moving parts into account.The static deformation rules of X,Y,Z guides mounting surfaces along assembly process are summarized through the static analysis,which can provides a theoretical basis and data support for assembly geometric error adjustment.Based on the error propagation model mentioned above,the paper comprehensively analyzes the accumulated error of the guides mounting surfaces of the precision machining center and put forward an adjustment strategy to offset the assembly deformation error by control the part geometric error.The adjustment value is determined through the comprehensive analysis of the static deformation curves.Besides,two methods to eliminate the assembly deformation error are proposed: correcting the mounting surface of the guide rails by means of anti-deformation principle and scrapping adjustment of large component based on the support pre-deformation design.The proposed adjust method is applied to the assembly process of a typical precision horizontal machining center,the results show that the assembly error can be decreased and the precision can be improved effectively by this method.