| With the continuous development of modern manufacturing technology, the traditional manufacturing industry has undergone tremendous changes. The positioning precision, guidance accuracy and feed rate of transmission mechanism have been improving constantly, bringing major changes to the traditional steering mechanism. Linear rolling guideway with its unique character has been gradually replacing the traditional sliding linear guide, gaining wide utilization in industrial production. The typical test system of the current four-slider workbench driven by ball screw is an integral part of implementing agencies to CNC servo system. To ensure the high stability, it is necessary to undertake a needed analysis specialized in mechanics, statics and dynamics.This paper takes SZHT2020-P4type CNC precision workbench installed with linear rolling guideway (LRG) of GGB25BA four direction equal load narrow type as the research object. Research various performances of the LRG precision workbench through combined method which includes theory, test and finite element analysis (FEA). According to the shortcomings of LRG, for example, poor rigidity, and complicated structure, this article aims at the characteristics of the two aspects, mainly research on mechanical properties, static and dynamic characteristics of the LRG and CNC precision workbench. The main content of this paper includes the following aspects:(1) Have theory coverage of the LRG research significance, domestic and international current status in the development of LRG and its latest research trend on theory which has been acquainted. The author brought a new research method which is combined with theoretical research, dynamic testing and FEA.(2) Corresponding analysis of LRG on mechanics has been made. Several important parameters that affect LRG working performance have been analyzed. And analysis is given to the elastic hysteresis loss which is one of the sectors that impact friction force, and then we get a more accurate friction force. The theoretical load formula of each slide block on precision workbench is deduced. Check the working performance of LRG through test condition load. The relationship of the speed between the two directions has been got as the precision workbench moved along linear and parabolic trajectory. Program a system to verify the theory and demonstrate the system.(3) Use ANSYS Workbench software to take static analysis of the single slider guide. The author try to obtain an unknown elastomer interlayer through cut-and-try work method, so as to substitute the complex relationship between the joint among steel ball, cage and raceway contacts. The rigidity deformation of LRG generated within several rated load, should meet the stiffness requirements. So an accurate finite element model (FEM) is established.(4) The static stiffness of LRG could be identified by the method of FEA. The joint surface is simulated by spring with damper. The author has established dynamic model of LRG, derived the theoretical formula of its natural frequency and calculated the results. The natural frequencies of the first6orders and their corresponding vibration modes have been got by analysis of FEA, and it is proved that the dynamic performance analysis of the FEM and theoretical modal is accurate by comparing results.(5) Deliver FEA to static and dynamic characteristics of the whole precision workbench. And solve the static stiffness. Based on the dynamic characteristics of workbench, modal analysis has been made, and the natural frequency and vibration mode of structure have been determined.(6) Did the dynamic experiment to workbench by using HP3566A dynamic signal analysis system, and adopted hammer method. The natural frequency and vibration mode of workbench have been measured. And the actual dynamic properties of precision workbench have been obtained. It is verified the correctness of the FEM by comparing FEA results.This paper has a lot practical significance for efficient quality promotion of LRG. And it also provides an important means of theoretical and experimental devices for the exploitation of new products. |
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