Design method for the length of auxiliary springs with few pieces of parabola with variable cross-section in end contact

Abstract

The invention discloses a method for designing the length of an end-contacting few-piece parabolic auxiliary spring with variable cross-section, and belongs to the technical field of suspension leaf springs. The present invention can design the required value according to the structural parameters of each main spring, the number of sheets of the auxiliary spring, the thickness of the straight section at the root and the thickness ratio of the parabolic section, the modulus of elasticity, and the composite stiffness of the main and auxiliary springs, and take the length of the auxiliary spring as the Design parameters, establish a design mathematical model about the length of the auxiliary spring, and use the Matlab program to obtain the design value of the length of the auxiliary spring. Through examples and ANSYS simulation verification, it can be seen that this method can obtain accurate and reliable design values ​​of the length of the auxiliary spring with a small number of parabolic cross-sections in contact with the end, and provides a reliable design method for the design of the length of the auxiliary spring of this type of main and auxiliary springs. . Using this method can improve the design level, product quality and performance of the primary and secondary springs with variable cross-section, and the ride comfort of the vehicle; at the same time, it can also reduce the quality and cost of the suspension spring, as well as the design and test costs, and speed up product development.

Description

technical field [0001] The invention relates to a vehicle suspension leaf spring, in particular to a method for designing the length of an end-contact few-piece parabolic auxiliary spring with variable cross-section. Background technique [0002] In order to meet the variable stiffness design of the vehicle suspension under different loads and the lightweight requirements of the vehicle suspension, a small number of primary and secondary springs with variable cross-sections are usually used. Due to the complex force of the first main spring of the small variable cross-section main and auxiliary springs, it not only bears vertical loads, but also bears torsional loads and longitudinal loads. Therefore, the end of the first main spring is actually designed to be straight The thickness and length of the section are greater than the thickness and length of the straight section at the end of each main spring, that is, most of them use a small number of variable-section leaf sprin...

AI Technical Summary

Problems solved by technology

However, because the straight sections at the end of each main spring are not isomorphic, the length of the secondary spring is smaller than the length of the main spring, and when the load is greater than the effective load of the secondary spring, the deformation and internal force of the primary and secondary springs are coupled. Previously, previously The design method for the length of the auxiliary spring and the auxiliary spring of the end-contact type few-piece parabolic variable-section primary and auxiliary spring has not been given

At present, engineering designers mostly ignore the non-isostructural ends of the main spring, and regard the auxiliary spring as approximately equal in length to the main spring, and directly subtract the stiffness value of the main spring from the required value of the composite stiffness of the main and auxiliary springs as the stiffness of the auxiliary spring. Then the length of the secondary spring is approximated. Therefore, it is difficult to obtain an accurate and reliable design value for the length of the secondary spring, which cannot meet the precise design requirements of the end-contact small-piece parabolic variable-section primary and secondary springs.

Images