1 Structure description and interference analysis of the internal milling parallel machine tool The structural diagram of the internal milling parallel machine tool is given, and the structure diagram of the external milling parallel machine tool is given. It can be seen from 2 that the main area of ​​the inner milling and the outer milling is that the inner milling parallel machine tool places the workpiece to be processed between the moving platform and the fixed platform, and the outer milling parallel machine tool places the workpiece on the moving platform and the fixed platform. Outside. Compared with the external milling parallel machine tool, the internal milling parallel machine is more complicated than the external milling parallel machine because the workpiece is placed between the moving platform and the fixed platform. However, due to its low cost, the structural size is smaller than that of the external milling parallel machine tool, and the tool is processed and precision designed. It is easy to observe from all angles, and the motion simulation can be performed as a motion simulator after removing the workbench and the electric spindle, which is very suitable for teaching in colleges and universities. In order to meet the needs of the market, we are preparing to develop a new type of internal milling parallel machine. The machine tool is driven by a servo motor. The transmission mode is driven by a motor. The screw drives the nut. The nut is located at the center of the moving platform. This structure avoids placing the nut between the moving platform and the fixed platform to form a cantilever beam. Thereby improving the rigidity and accuracy of the machine tool. The six Hook hinges of the fixed platform are located on the same plane and distributed on the same circumference. To avoid the singular position, the angle between the adjacent Hook hinges to the center of the fixed platform is 30° and 90°. The moving platform is located on the same plane but not on the same circumference, but adopts the principle of 33, that is, the phase-to-phase Hooke hinge is located on the same circumference. This structure avoids the interference of adjacent lead screws above the moving platform and improves the Jacobian. Matrix performance indicator parameters. The Pro/Engineer 20002 two-dimensional shape drawing of the machine tool is shown. It can be seen that the screw rotating belt moves the moving platform to form various spatial postures, so that the electric spindle mounted on the moving platform drives the tool to process the space surface. When the moving platform moves, the following interferences will occur: 1 between adjacent servo motors; 2 between the lead screw and the table; 3 between adjacent screws; 4 between the lead screw and the electric spindle; 5 phases Between the adjacent tiger's hinge; 6 swing angle of the hinge; 7 between the screw and the moving platform. In the above seven cases, since the interference between the adjacent Hook hinges is mainly due to the structural size of the Hook hinge, only the other six cases are discussed in this paper. In the overall modeling process, the six lead screws are divided into three groups, and two adjacent groups are one group. Since any two of the three groups are identical in structure, and the three groups are relative to the z-axis coordinate line.芫 Fully symmetrical, and the working space trajectory planning of the moving platform is a cylindrical space. Therefore, during the movement of the moving platform, any set of spatial trajectories is equivalent to the other two groups, so for the screw, only the certificate is required. The interference problem of the motion space of two adjacent lead screws. From the known (1, 2, 3 points in the figure, the lead screw 1, the lead screw 2 and the lead screw 3), the six lead screws are divided into three groups and divided into two ways. The first way is the lead screw 1 and The lead screw 2 constitutes a group, and the method is used for analyzing three kinds of interference situations such as 1, 2 and 6, and the second way is that the lead screw 2 and the lead screw 3 form a group, and the manner is used for the pair 3, Four kinds of interferences such as 4, 6, and 7 were analyzed. 2 Internal milling parallel machine tool motion modeling 2.1 Internal milling parallel machine tool interference analysis motion modeling idea Parallel machine tool workspace size is one of the important evaluation indicators of machine tool performance, how to optimize as far as possible given the machine tool structure parameters The large working space without interference has become the dominant idea of ​​machine tool design. During the tool processing, various interferences occur at the boundary of the set workspace, so this paper is in the process of interference analysis. The fixed coordinate system Qcz is established in the center of the fixed platform, and the plane of Qcy coincides with the plane of the center of the fixed platform. The dynamic coordinate system 01x1y1z1 is established on the plane where the center of the moving platform coincides with the plane of the center of the moving platform. According to the inverse solution principle of the internal milling parallel machine tool, the motion model of the lead screw is established in the fixed system Oyz: the vector of the point B of the heart is the center of the center of the platform 0 to the point of the point A is the center of the moving platform center i to point B. The position vector of the center of the moving platform. The motion model of the moving platform can transform the mutual motion between the moving platform and the lead screw into the movement of the screw relative to the moving platform according to the inverse solution principle of the machine tool, that is, the motion of the relative coordinate system of the lead screw Oiyiz * the relative system Oiz The rotation transformation matrix is ​​represented by the Euler angle as: 3 matrix. The motion model of the lead screw is transformed into a position vector of +j+Zi; AB) is the transposition of the vector ABf. ! Interference calculation of the internal milling parallel machine tool According to the actual structure of the moving parts, the interference is judged into two cases (one of the two interference parts is a cylinder (2) two interference parts, one is a cylinder and the other is a non-cylindrical body. For the first case, the interference judgment of the machine tool structure can be divided into two cases: the intersection of the two faces and the intersection of the different faces, so as to establish two formulas Liu Wentao. Performance analysis and research of parallel machine tools. Harbin: Harbin Institute of Technology 2000. Wang Yuxin Wang Yiming. A New Fangtong J Jianghong Gao Benhe, Jia Wei, et al. Interference analysis in the solution of 6-DOF parallel robot active space. Mechanical Science and Technology 20001911) 75-77. Huang Zhen, Kong Lingfu, Fang Yuefa. Parallel robot mechanism theory and control. Beijing Mechanical Industry Press, 1997. (Finish) Silicone Baby Cup,Foldable Silicone Snack Cup,Snack Cup With Handles,Anti-Sprinkle Silicone Foldable Cup Hubei Daxin Electronic Technology Co., LTD , https://www.hkdaxinrubber.com