Research On Dynamic Analsis And Optimal Design Of Forklift Frame Oriented To Damping

Forklift frame works as a main load bearing body, and its low order modal reflectthe whole dynamic stiffness performance of the frame, moreover, provide a key index ofcontrolling the general vibration characteristics. While Forklift is working, forklift frameis affected mainly by two kinds of exciting force. One is the harmonic force caused bycombustion pressure of the engine working stroke and the inertia force of reciprocatingpiston, the other is the random excitation of road roughness on the wheel. Therefore,solving and optimizing the low order modal parameter of the frame is very significant toavoid resonance in Engine Idling.In order to solve the problem of resonance in Engine Idling of a kind of forkliftframe producted by Hangzhou Forklift Truck Co., Ltd. This paper studies dynamicperformance of the frame through finite element method. In order to gain bettercomputational performance from finite element model, the paper selects the differentelements, and builds four kinds of finite element model of the frame, according to theframe shape. As there are many factors involved in shell element molding work, the paperintroduces the key work, while using shell element to model the frame.Model analysis is carried out by ANSYS to calculate first ten modes of four kinds offinite element models in the free constraint and evaluate four models by calculationsituation. Then the modal experiment is performed to verify the analysis results of thefinite element models. Through the frequency analysis of the engine in idle speed, it isfound that the first bending frequency is similar to excitation frequency, which is thereason of frame resonance in practice.In order to eliminate the idle resonant, it is necessary to make the first naturalfrequency of the frame away from incentive frequency of engine.This paper provide anoptimization design for enhancing first natural frequency of the frame. The thickness of influences the mechanical properties and the seismic performance of reinforced concretestructures. Besides, the paper the advantage and disadvantage of using solid element tosimulate the seismic response of reinforced concrete.