Forklift Structural Vibration Damping Characteristics And Research

Forklift as the main field operation vehicle, is widely used in factory, port,warehouse, station, airport and so on, undertake the goods loading andunloading, handling, stacking, and short distance transportation. Forkliftreliability and comfort not only affects the production efficiency, but alsoinfluences the driver’s physical and mental health. Therefore, it’s necessary tostudy its vibration characteristic and reduce its vibration damping noise.Hitherto, scholars domestic and overseas have made some researches to forkliftvibration, and put forward a series of passive and active vibration reduction plan.But those researches are rarely considered the influence which structure throwsto seat vibration, just take the seat system alone to study, not put the seat into theentire forklift system, ignore the impact which the overall vibration exertsforklift seat.In this paper, through analyzing HeLi PCQD20type internal combustioncounterbalanced lift truck, by measuring its main parameters, to draw its CADengineering pattern. Considering its structure, especially the structure of frontand rear axle, use Solidworks to build the virtual prototyping of the forklift.Through theoretical analysis and structure research, looking the car-frameand driving structure as rigid bodies, so its main vibration attenuation units aretires and seat. Define its stiffness coefficient and damping parameter, combiningthe engine and ground excitation influence forklift vibration, using solidworksown vibration simulation module, meshing, take forklift model for modalanalysis, in order to get its inherent frequency and mode of vibration. Comparedwith the real vibration data, remodify its model to make it in conformity with theactual situation.After the finite element analysis, we can get the dynamic responsecharacteristic of the fork truck and the distribution of its mean acceleration，byusing the principle of linear regression to fitted curve, approximately have theexternal source’s mathematical model. Analysing human body structure,considering the scale of analysis and computational complexity, setting up four degrees of human-chair model. Depend on Matlab, combining optimizationalgorithm to optimize the seat parameters，reducing its amplitude and making itfar away from the resonance of human body, to obtain the purpose of vibrationreduction and noise reduction. Finally, combined with ergonomics, evaluatingthe effect of forklift seat vibration reduction.The paper has reduced the vibration of the truck driver while the fork truckis in the running state and provided theory basis for the vibration reduction offorklift and seat design.