Kinetics Characteristics Research Of Cab Suspension For Commercial Vehicle

Integrated the development project of commercial vehicle cab’s air mount and rubbermount, this paper took the diaphragm spring of mount and rubber mount of commercialvehicle’ cab as study object. By means of non-linear finite element theory, non-lineardynamics, the characteristic of air spring was theoretically analyzed, tested and simulated.This paper stated the structure and characteristic of air spring and rubber mount, introducedthe development and research status. Base on this, the consequence of further study wasbrought on the desk.The contents of this dissertation are:1. The basic theory of finite element and finite element analyzing software ABAQUSused in this study was briefly introduced. And then the material nonlinearity, geometrynonlinearity, contact nonlinearity and the air-structure coupling characteristic of air springwere analyzed, the necessary of induction of finite element method is represented. The rubbermodel and material parameter, the rate of change of the rebar geometry peculiarities in thecourse of working, the gas-solid coupling between the gas elements and the rubber elementsand the change of gas elements volume were deduced in detail by the finite element analysisbefore building the model of air spring. And the contact theory, the judge and converge ofcontact condition were analyzed.2. In this paper, the method of setting up the finite element model of air spring was stated.The process of setting up the model was introduced, including selecting the types of elements,defining the parameters of materials, defining the contact conditions and boundary conditionsand defining the step of analyzing. And then the static characteristics were analyzed by finiteelement method, and the results were compared with the testing results to prove the finiteelement model right.3. The static characteristics were analyzed by finite element model, its involved theeffect to the static bearing ability of initial inflation pressure, angle of rebar, spacing of rebarin the plain and the number of rebar plane. The results showed that the static bearing ability ofair spring increased as the initial inflation pressure or spacing of rebar in the plain increased,and as the angle of rebar or the number of rebar plane decreased. The initial inflation pressure,angle of layers had more contribution, while the spacing and the number of rebar plane hadless. All these results could provide a basis of designing and optimizing of air spring.4. Taking a complex rubber mount as a subject, three methods including empiricalformulas, finite element theory and experimental test for its three dimensional static stiffness are used. Then relative errors of the three methods are obtained and an explanation for theirsources is given. However, the relative errors are within the allowance in practice. Thus, as tothe specific engine mount, the above-mentioned methods for its three dimensional staticstiffness are accepted and will shorten the cycle of product development.