| According to the housing of a certain type of dual diaphragm brake vacuum booster with great stress, prone to fatigue crack causes fatigue strength does not meet the problem, this paper carries on the analysis to the structure of the booster, find out the stress characteristics of the relevant parameters, calculation. According to the load and the fatigue strength theory to determine the relevant parameters of shell finite element analysis, and carried out on the shell finite element static strength and fatigue strength analysis.By analyzing the factors and the housing riveted bolt position effect on the fatigue strength of the riveted bolt, put forward to the pressure in the cylindrical surface of the plate hole is fatigue strength analysis of casing influence factors can’t be ignored, and calculate the distributed force of size, through comparative analysis found that, less influence of static strength that case on the distributed force, but more influence of the fatigue strength of housing.Based on the finite element analysis results, found that the influence of casing stress and strain distribution is the main factor affecting the housing fatigue strength, and by changing the lining board shape and improving the lining board stiffness, the realization of the casing stress and strain distribution improvement is the key to optimize the structure of housing. Combining the optimization design theory established the casing lining board shape optimal design objective function, according to the lining board shape optimization design variables resulting solutions to determine the optimized, and the lining board optimization. The finite element analysis on the shell of the optimized structure, found that the fatigue strength of the shell structure than the national standard after optimization. |
PDF Full Text Request