Research On Frame Assembly Precision Of Medium-low Speed Maglev Vehicle

Maglev frame is one of key parts of maglev vehicle.Its main roles are carrying car body,levitating,steering and transferring traction and brake force.It may significantly influence vehicle's safety,comfort and reliability.A proper assembly precision is an important factor to ensure the operation performance of maglev frame.The research object of this paper is the maglev frame of a new type medium-low speed maglev vehicle which suspension air spring is in the middle of frame.With finite element method and dimension chain theory,this paper investigated the assembly precision of maglev frame and proposed requirements.Taking the requirements as a reference,the tolerance of each part is analyzed and optimized.This paper has completed the following tasks:The three-dimensional solid model of new medium-low maglev frame is built.And the model is simplified according to the requirement of finite element analysis.This paper conducted statics analysis to the maglev frame with ANSYS Workbench,a software of finite element analysis.There are 5 kinds of statics working conditions.They are parking,static levitating,normal running,electric braking and mechanical braking.The methods of applying loads and constraints are decided during the analysis according to the real working conditions of maglev frame.The deformation data of each condition is got through statics analysis.This paper paid more attention to the deformation data of electromagnet plates' upper surface,motors' lower surface and vertical sleds' lower surface.Furthermore,the characters of maglev frame in different conditions are analyzed and summarized.Aiming at parking and levitating states,this paper analyzed the relation between frame and track.Based on dimension chain theory,this paper analyzed the assembly precision requirements that should be satisfied combining with the levitation control precision,the geometry precision of track and the deformation data of finite element analysis.Finally,a conclusion is drawn that the distance between vertical sleds' lower surface and electromagnet plates' upper surface should be 96+1.0-2.7mm.With computer aided tolerance analysis software,the tolerance of maglev frame is analyzed according to the original design.It comes out that the original design cannot meet all the requirements.After optimization of some parts' design,the tolerance of maglev frame is analyzed again.The result shows that new design could fairly meet the assembly precision requirements of maglev frame.