Establishment And Application Of The Assembly Size Model Based On Element Features

It was very important to reasonably ascertain the dimensioning mode of the various parts, and then solve all the dimensioning and tolerances for mechanical product design when its structure and principle was defined. And this required a complete,accurate and reasonable assembly dimensioning model. This paper analyzed the assembly function of the various components, accomplished the assembly size model on the basis of their elemental characteristics, introduced the establishing method of the dimensioning model, and established the perfect and precise assembly dimensioning model of the whole assembly from the shortest dimensional route's view, which implemented the accuracy and the rationality the dimensioning mode of parts. Dimensioning mode should not only be able to express all the dimensional relationship, but also able to express all relationship between benchmarks, and this paper would build the assembly dimension model through the establishment of the assembly dimension mooring which had some merits in no graph drawing , expediently looking for the assembly dimension relations and easily expressing structural characteristics for the assembly drawing. This is a new way to automatically establish the assembly dimensioning model with computer.In this paper, the following work has been completed:(1)Being defined the concept of the target size, and classified so as to completely and correctly identify it through analyzing the functional relationship of the assembly between the various elemental characteristics of parts.(2)Utilizing the shortest path search algorithm in Graph Theory to automatically establish the assembly dimension model based on the element features.(3)Using directed graph as a mathematical tool to accomplish the generation of the dimensioning mode of parts according to the dimensioning principle accuracy, integrality, clearness, and rationality.(4)Exploiting the assembly size model calculation software served VB and Access 2003 database as platform, and detailed introduce the entire implementing process of the system with example.