Analysis And Design Of Assembly Precision Of Automatic Weapon Based On 3D Tolerance Model

With the development of modern manufacturing industry,the conditions of automatic weapons business had been greatly improved.But due to the late start and some problems in the industry,such as drawing conversion waste time and effort,a lot of filing.For the traditional design environment,the dimensional tolerance analysis can't meet the requirements of modern product design,manufacture and simulation analysis.Today especially it has been highly prevalent in the CAD/CAM;it has become a bottleneck restricting the development of three-dimensional digital integrated application technology.In order to promote the development of the automatic weapon industry,the transformation from the 2D dimension chain to the development mode of the 3D digital prototype.In order to realize the integration of design and manufacturing information based on the whole 3D model.To complete the project can be applied to practice.The research contents of this paper include the following aspects:(1)Combined with the characteristics of automatic weapon structure,parametric modeling of geometric features by using the theory of small displacement torsor.The tolerance domain models of typical dimensional tolerance and geometric tolerance had been summarized.Establish the model of deviation transfer by using homogeneous coordinate transformation matrix.Finally,an example of a certain type of automatic weapon locking mechanism had been analyzed.(2)For complex products,such as automatic weapons,tolerance analysis involves a large amount of calculation,high accuracy requirements.In this paper,we studied the method of Monte Carlo analysis based on low deviation sequence,by optimizing the random number of variables,and efficiently generate a set of high quality samples with uniform distribution To solve the deviation transfer model of the locking mechanism,the variation statistical law of the deviation of the analysis target along the three axis had been obtained.(3)Based on the maturity of 3D digital prototype,the 3D assembly deviation model had been established with the help of the locking mechanism and the elastic supply mechanism as an example.Use Vis VSA as a tool for assembly tolerance analysis.Finally,the distribution statistical law of the analysis target and the contribution of each component and the influence factors had been obtained.(4)To optimize the analysis of assembly precision.Based on the contribution degree analysis and calculation,the optimization model of the product processing cost and quality loss as the optimization objective had been established.In the end the optimization analysis results had been obtained and verified.(5)Combined with the above work,the method and the analysis results were used to study the assembly precision control technology of the typical mechanism of automatic weapon.Put forward the adjustable size assembly method and the key assembly dimension tolerance control method for the typical structure of automatic weapon,and designed special measuring tool to control assembly precision.Finally,it had been verified that the clearance tolerance was controlled within the specified range,and the reliability of the feeding mechanism was guaranteed,and the method had been proved feasible feasibility.