Structural Optimization Design And Static Stiffness Test Of Cross-slide Of Machining Center

This subject comes from National Major Science & Technology Project'Digital Design and Software about Dynamic, Static and Thermodynamic Characteristics of the Machine Tools'(NO.2009ZX04014-034), National Major Science & Technology Project'VHT Series of Vertical Turning and Milling Centers'(NO.2009ZX04001-031) and National Science and Technology Support Program'Development of Multi-axis High-speed Gantry-type Series of CNC (NO.2007BAF21B01).With the development of the modern industrial technology, the demand for performance of the machine tools is increasingly high. Experience and analogy are heavily relied on and theoretical guidance is quite lacked in the process of the tradition design, which leads to poor performance of the product and long design cycle. By means of structural optimization design of the Cross-slide of the VD50-type vertical machining center in the paper, the stiffness and natural frequency of the Cross-slide was improved. And the shortage of the acceleration capability of the machine tool's Y direction was solved by reducing the mass of the Cross-slide. The static stiffness test of the Cross-slide was carried out, and the calculating result by finite element method and the test result were contrasted. The accuracy of the finite element method was verified by the contrast. The major study in this paper is as follows:(1)The working conditions of the VD50-type verical machining center were analyzed. The constraint condition of the Cross-slide was defined. The mechanical model of the Cross-slide was built, and the load on the Cross-slide was calculated by the mechanical model. And then, the boundary conditions which lay a foundation of structural optimization and analysis of the Cross-slide were defined.(2)The structural optimization design of the Cross-slide was carried out by structural design based on topology optimization. First, the topology optimization of the Cross-slide was carried out base on'Hyper Works'platform. Then, the structural optimization design of the Cross-slide was carried out according to the topology optimization result. And in the structural optimization designing process, the casting technique requirements and functioning requirements were considered. By calculating and comparing, the mass of the new Cross-slide was 14% reduced and the stiffness and natural frequency of the new Cross-slide was better compared of the original Cross-slide. The problems of lack of stiffness, too heavy and insufficient Y direction acceleration capability were solved. (3)Static stiffness test of the Cross-slide was carried out. The static stiffness in several key positions of the Cross-slide which provided reference to the improving design of the Cross-slide was got. The finite element analysis about the static stiffness of the Cross-slide was carried out. The relative error of the finite element calculating result and the test result was about 10%, the finite element calculating result were accordant with the test result under the most working conditions except some working conditions under which the relative error reached 20% around. The rationality of unit type selection, mesh mode and loading manner of the boundary conditions in the process of using finite element method were verified.