The3D Tolerance Analysis And Optimization Research Of Tail Shaft Assembly

It’s known that the tolerance design of mechanical products will not only affect the accuracy and performance of the production, but also related to the quality and cost of the production. With the mechanical product precision, performance and other various quality requirements improve, especially in the face of increasingly fierce market competition to shorten the development cycle, reduce the manufacturing cost is imminent. In the stage of product design to analysis and optimize tolerance, can not only provide reference for product design, but also can avoid some assembly quality problems. In recent years due to the tolerance analysis and optimization techniques, especially3D tolerance analysis and optimization technology unceasing development, as in a virtual environment for product tolerance analysis and optimization is provided and possible conditions, but also for the existing mechanical design method to supplement and perfect.This topic originates from the Marine Institute for an underwater vehicle body design, the underwater vehicle is attacked by underwater and surface targets as a weapon.With the continuous development of modern naval warfare, its reliability and sailing without a trace (attack of concealment) and other performance indexes put forward higher requirements, and the tail shaft as a whole vehicle power transmission parts, assembling quality and tolerance design quality is particularly important. Design stage before the subject has been the traditional CAE analysis, partial prototype trial sailing body and tail shaft, complete the assembly of the sailing tail shaft parts in accordance with the design tolerances, the test found that the inner shaft and outer the front bearing of the shaft is easy to wear, and presence of the noise is large. After the survey findings, the main reason for these problems may be unreasonable tolerance design. In order to further improve the quality and performance of the product assembly, and to reduce production costs and design cycle, the requester for the use of three-dimensional tolerance analysis and optimization techniques the tail shaft sub-component assembly tolerance analysis and optimization, and the following work:(1) To studied the existing tolerance analysis technology, especially for the3D tolerance analysis technology.By compared the existing techniques of tolerance analysis and get the conclusion of3D tolerance analysis technology more adapt to the modern product development needs.(2) In this paper using the3D vector chain model to perform tolerance analysis, and studied the vector loop of the3D CAT system, the extraction of tolerance function and tolerance analysis method.(3) Combined with prototype problems, using3D tolerance analysis technology on the tail shaft assembly tolerance analysis, and get an initial evaluation.By the way, to the critical tolerances which make a great influence to the tail shaft assembly performance and quality, and provide an advice to further optimization.(4) According to the information of the tolerance analysis pass rate, contribution, sensitivity, extreme value, optimize tail shaft tolerances, and compared with the results before the optimization. Provide guidance for the design and improvement of the assembly qualify.(5) Combined with part of the impact of external factors on the tail shaft to tolerance analysis.Get more close to the actual analysis results, and to provide reference for the further improvement of the product tolerances.This paper combinate with the actual product design and demand, do above research work.The final results not only provide a reference for the improvement of the product performance and quality, but also provides a theoretical basis for the product tolerance design. On the otherhand provides some reference for other mechanical products research, enrich and supplement the existing method of mechanical design.