On Experiment Design And Finite Element Model Building Of The Joints Of Machine Tools

This paper does some research on celerity and optimize design about machine tool. Mensurate the coefficient of the stiffness and dampness of the joint; obtain a design method of getting high stiffness and dampness joint; set up a syntheses finite element analysis model.This paper bring out a useful method on testing the actual contact ratio of joints, which is base on relative displacement of vibration. The method eliminated the influence of vibration of base by predigest the model to single freedom system, as a result, it bring up high precise of identification. Lots of useful data on tangency ratio of joints in several normal conditions can also be found in this paper. By means of experiment and calculation, we work out a kind of designing method of getting high stiffness and dampness joint. Research work indicates that, given an appropriate predistortion on joints the stiffness and the dampness of the joint can be advanced greatly. Accidence discuss has been made on this topic.Research work has been done on dynam characteristic of the spring interlayer plate or girder structure, the stifThess and dampness matrix of dual plate--spring layer element was educed. The elements of the matrix are different with the matrix educed by normal means, which reflect the actual characteristic of joint.Both the new matrix and the basic characteristic parameter of the joint identified by experiment were applied in the finite element calculation based on pole model of machine. The result suggests that the characteristic parameter of the joint identified by experiment was veracious, the spring interlayer has great impact on dynam characteristic of the whole structure, the discrepancy of the natural frequency is 7.4%, and the new matrix advanced by this paper was more efficient and reliable in solving similar problem.Some basic theory of finite element and model testing was included in this paper, which is needed to understand this paper. The paper also covers some microcosmic study on dynam characteristic ofjoint.