A study on The Effect of Tolerances and Forces on deformation of Mechanism

Autor: 何益君
Rok vydání: 1999
Druh dokumentu: 學位論文 ; thesis
Popis: 87
As product competition and customer requirement on product quality become higher, product with low quality, though cheaper, loses its market day by day. High quality, however, often means high cost. It requires improvement on both product design and manufacturing to balance product quality and cost. To control product accuracy and quality, one has to start with functional requirement and tolerancing and fitting design. This thesis combines forced deformation and variation of components due to manufacturing tolerances to affect the accuracy of a mechanical structure under external forces. Tolerance stack-up of a structure by tolerance analysis and forced deformation by finite element method (FEM) are first introduced in this thesis. Shape variation of components due to manufacturing tolerances is then introduced to investigate the “ real ” structure, which is then analyzed by FEM to investigate the real deformation of the structure. Together with shape variation due to tolerances, the deformation of such a structure is then compared with the “ ideal “ structure to find the affects of manufacturing tolerances. The mold-clamping mechanism of a plastic injection machine and the soldering mechanism of an integrated circuit wiring machine are used in the thesis to illustrate the method. It is found that tolerance plays an important role in the deformation of a structure/mechanism with low stiffness.
Databáze: Networked Digital Library of Theses & Dissertations