Frequent movements in a vacuum environment must achieve important factors

Vacuum measurement using PKR251 vacuum gauge and vacuum gauge with a measuring range of 1×102. Optimized design of the vacuum chamber structure and the finite element analysis table of the bench mounting reference table is the reference platform for mounting the etched specimen, and is the specimen scanning ion beam. The carrier for continuous dynamic etching, which is mounted on two rolling guides. The scanning motion is based on a servo motor installed outside the vacuum chamber as a power source, and the step size is refined by 1:30 planetary reducer and then two pairs of 1:2 The spiral bevel gear transmission shaft of 1 passes through the magnetic fluid sealed bearing and transmits the motion to the screw-nut pair (precision screw rod) in the vacuum chamber, thereby driving the workbench carrying the test piece to reciprocate along the guide rail. Due to the requirements of the engraved grating, Table 1 shows the main technical parameters of the table.

It is not easy to achieve such accuracy with frequent movements in a vacuum environment. Correctly positioning the mounting guides for precision components such as table guide guides and moving screw rods is a very important factor to meet the above requirements. The problem with square vacuum chambers is that each side wall must carry more than 10 tons of vacuum force. Even with reasonable ribs, the deformation of the vacuum chamber is still unavoidable. Therefore, if the guide rail is directly placed on the bottom wall of the vacuum chamber, deformation of the vacuum chamber causes the guide rail to bend, which will cause the table to lose its flexibility and uniformity of movement and even become stuck. To this end, we have optimized the design of the vacuum chamber structure, through the finite element analysis of its force deformation, and rational arrangement of ribs, first control the maximum deformation of its bottom wall at about 1mm, and then take the structure Compensation measures to make it meet the accuracy requirements. Mixed-type vacuum chamber model. The vacuum chamber model ANSYS divides the grid by two methods: free partitioning and mapping partitioning. Since our model does not have a regular topology shape, it uses free meshing, which is automatically generated by the software after a given element type and unit edge length. Grids and cells. The vacuum chamber material is stainless steel (1Cr18Ni9Ti). The load is the atmospheric pressure of the four outer surfaces. The four models are calculated respectively, and the deformation of the bottom wall of each model, the specific parameters and the calculation results are obtained.