Research On Muti-leaf Spring Of Commercial Vehicle

Suspension is the important part of a car, which has a big effect on auto smooth, operating stability and other performance. Leaf spring has simple structure, easy maintenance and low cost. Also it is widely used in cargo automobile suspension.Therefore,the research on leaf spring has extensive significance and value. In this paper, we use finite element analysis on multi-leaf spring. Also we analyze harshness on the steel spring suspension system with simulation.First of all, we use UG6.0 build multi-leaf spring 3-D modeling in free state before assembling and establish multi-leaf spring finite element model with ANSYS12.0.Then simulate the clamping assembly process, the simulation analysis of the leaf spring internally generated prestress.And compared with the theoretical calculation, verify the correctness of the assembly simulation.In order to elaborates on the influence of assembly prestress to steel spring, this paper analyzed the stress distribution of the steel spring between assembly prestressed and no assembly prestressed under full condition. And then we put forward the necessity of assembly prestress existed.Secondly, we build 3-D modeling of different thickness combinatorial steel spring after assmbling.Using ANSYS12.0 on static characteristic analysis, and simulating loaded process of leaf spring. According to add load and leaf spring produced the corresponding displacement, we can calculate stiffness of the different thickness combination of steel springs.Thirdly, based on the analysis of statistical characteristics of random road, we establish a mathematical model of filter white noise random road and the corresponding road simulation model in MATLAB/Simulink.Finally, we establish the 1/4 passive suspension mathematical model based on the simplified vehicle vibration system.Meanwhile,we establish its simulation model in MATLAB/Simulink and analyze passive suspension harshness of different spring stiffness.This paper systematically analyzes the whole process from before assembling to assembled and using of leaf spring, also plays a guiding role for the users to select leaf spring. At the same time, it has the high reference value to the actual research on leaf spring. Finally it will reduce the time of physical prototype experiments and shorten the period of design cycle. And the quality of design can also be improved.