Design method for end part- and root-reinforced few-leaf variable-section steel plate springs

Abstract

The invention relates to a design method for end part- and root-reinforced few-leaf variable-section steel plate springs, and belongs to the technical field of suspension steel plate springs. The design method disclosed by the invention comprises the following steps: determining the toot thickness he of an equivalent single leaf according to the structure of each steel plate spring, a design rigidity, the thickness ratio of oblique line segments on the root and the end parts, and the thickness ratio of primarily-selected parabolic segments, and determining the maximum allowable thickness [h2] of the root according to an allowable pressure at first; then designing the number N and the root thickness h2 of the few-leaf variable-section steel plate springs according to he and [h2]; and then designing the thicknesses and the lengths of straight segments on the end parts of each leaf separately according to the end part thickness beta he of the equivalent single leaf. Through ANSYS simulation and verification, the accurate parameter design values of the end part- and root-reinforced few-leaf variable-section steel plate springs can be obtained by virtue of the method, the design level and the performance of products are improved, the weights of the springs are reduced, and the running smoothness of vehicles are improved; and meanwhile, the design and test expenses are reduced, and the development speed of the products is increased.

Description

technical field [0001] The invention relates to a vehicle suspension leaf spring, in particular to a design method of a leaf spring with a small number of pieces and a variable cross-section with reinforced ends and roots. Background technique [0002] Compared with multi-piece superimposed leaf springs, the small-piece variable-section leaf spring has a reasonable stress load and tends to balance the stress load, saves materials and costs, realizes vehicle weight reduction, reduces wheel dynamic load, and improves vehicle driving safety. It also saves fuel and improves vehicle transportation efficiency, so it has good economic and social benefits, and has been popularized and applied abroad. For leaf springs with a small number of variable cross-sections, usually between the straight section at the root and the parabolic section, and between the straight section at the end and the parabola, an oblique line section is added, that is, a small-section variable section with rei...

AI Technical Summary

Problems solved by technology

Although some people have previously given a design method for a few parabolic variable-section leaf springs, for example, Peng Mo and Gao Jun once proposed a design calculation method for variable-section leaf springs in the 3rd issue of Volume 14 of "Automotive Engineering", This method can only be designed for the end and root unreinforced, and the ends are equal structure few parabolic variable cross-section leaf springs. Require

[0003] For end and root reinforced few-piece variable-section leaf springs, due to the constraints of deformation, stiffness calculation theory, equivalent thickness and split design theory of few-piece variable-section leaf springs, a simple, accurate and reliable method has not been given so far. Design methods, at present, mostly ignore the influence of the oblique line segment reinforced at the end and root, and directly approximate the oblique line segment as a parabolic segment, and approximate the design of the end and root reinforced few-piece variable-section leaf spring. Therefore, it is difficult to obtain an accurate Reliable parameter design value

With the simulation of computer and finite element simulation software, although some people have used the ANSYS modeling and simulation method for end and root reinforced few-piece variable-section leaf springs, this method can only be used for end and root of a given design structure. The simulation verification of the deformation or stiffness of the reinforced few-piece variable-section leaf spring cannot provide an accurate analytical design formula, let alone meet the requirements of the rapid development of vehicles and the development of modern CAD design software for suspension leaf springs

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