Analysis And Optimization Of A Type Of Internal-combustion Forklift Frame Vibration

The vibration of the forklift is the key element that influences the ride comfort and operability, how to solve this problem is one of the most issues that the manufacturers concerned.The paper based on the theory of FEA and modal analysis method to do vibration research on the forklift from the aspects of frame and the engine.According to the vibration problem of one product of my company, we analyzed the main structure from the forklift frame. Using finite element analysis software ANSYS for static,dynamic analysis, find out the main reason for the frame vibration, the vibration of forklift truck comes from the sympathetic vibration between the Forklift truck frame and the engine. How to avoid the lower frequency of the engine is the main purpose of the structural optimization. And structure improvement scheme is put forward. Through the analysis of each scheme comparison,the paper puts forward reasonable structure improvement, optimization design for the improved structure. Finally according to the results of the optimization of production prototype, test. This article are analyzed from the following aspects:First of all, establish a forklift truck chassis 3 d geometry model and processing. The frame is simulated by finite element method. According to characteristic of frame structure, the shell elements and the solid element are adopted. The frame is made up of many parts welded together. So we use the binding definition of contact between components, using hexahedral grid,to explore the grid convergence. Test the grid set reasonable state.Second, through to the frame in the static analysis under different working conditions,frame under loading is the biggest stress points are obtained. Modal analysis was carried out on the frame, frame in the first six order natural frequency and vibration mode. Determine the incentive frequency range of the road surface roughness and the engine. Show that the vibration of the frame. The vibration of the frame mainly comes from engine resonance between incentive and frame.Third, based on the analysis frame of the main causes of vibration, and put forward some solutions for the improvement of the frame structure. Through the analysis of each scheme comparison, it is concluded that by changing the beam and the thickness of the beam method can effectively change the frame of the first order natural frequency, low order to avoid the engine vibration frequency.Finally,according to the result of optimization, make prototype,And the prototype dynamic test, and compared with the finite element analysis results, are in good agreement,verify the calculation of the frame model, boundary conditions and the correctness of the simulation method and so on.