Research On Design Method To Improve The Supporting Capacity For Few-Leaf-Spring

Less leaf spring is usually used for minor car’s suspension system and is an importantautomotive safety components under the high load conditions. It’s main role is to pass thevertical force, to ease the shock and vibration caused by the uneven road, as connecteddevices for the transmission of the force and torque, and the transfer properties is directlyimpact on the vehicle dynamics performance such an the handling stability, the brakingsafety, the driving comfort and the driving force of acceleration. If we want to get a goodperformance car, only with the excellent performance of the small leaf spring. Before theproduction of leaf springs, it is very important to calculate its stiffness and stress. We canusually use a common curvature, concentrated load method and finite element method.First, this paper reviews the status of a small piece of leaf spring; using the method ofstructural mechanics to introduce small piece of leaf spring design concepts and derive theformula of the corresponding mechanical parameters; under the Hamiltonian symplecticdual variables system using the precise integration method and orthogonal test to analyzethe impact of the number of pieces, the arc height and the section size for the stiffness andelect a superior level of primary and secondary factors and the optimal mix. And the data ofthe orthogonal experiment is taken by the precise integration method.Then using the inter-belt method analyzes the exposure for the less leaf springstiffness’s impact; basing on the inter-belt theory, giving the contact thickness, consideringthe contact’s impact of leaf spring stiffness as a leaf spring stiffness perturbation, which is asmall amount and known by the common curvature method, contact and the leaf springdeflection in the film side is the same and consider it parallel to the leaf springs, thestiffness caused by the contact is a small amount perturbation for the spring stiffness, theestimate of the flexibility of the leaf spring system is too large, so while calculationintroducing a negative amount to lose the estimated large part. Analyzing the impact of thecontact length on the leaf spring stiffness finds that while the contact length increases, theleaf spring stiffness did not change significantly. While the contact thickness is different, the thicker the contact thickness the smaller the leaf spring stiffness. Under different excitationfrequency the impact of the contact of the leaf spring stiffness is that while the change ofexcitation frequency is from10-4to2Hz, the contact has no obvious influence for thespring stiffness; but while the excitation frequency is from2to10Hz, contact increaseswith the excitation frequency increasing..Again using the finite element analysis software ABAQUS to do the finite elementanalysis, calculating the stiffness of the leaf spring and drawing the stress curve. The paperuses the PRO/E software to model the leaf spring, the HYPERMESH software to do thepre-treatment and uses the ABAQUA software to analyze the impact of the variablecross-section of the stiffness of the leaf spring.Finally under the seven factors and two levels of interaction and no interactionconditions using the orthogonal experiment analyze stiffness characteristics under differentsectional dimensions of length, thickness combination. In orthogonal experiment using theABAQUS software calculates the different situations. While using the ABAQUS softwareto calculate the21kinds of interaction，it is found that the no interaction is not the optimalmatch.