Vibration Experiment And Analysis Of Mini Tiller

The main terrain of the southwest China is hills and mountainous. In this region, the land is narrow and decentralized, the transfer of agricultural machinery is extremely inconvenient, furthermore, a large number of rural labor force transfers to non-agricultural industries, the phenomenon of "elderly farming" and fallow land are quite prominent. Mini tiller has some advantages, such as simple structure, light weight, transfer convenient in field and inexpensive, so that can effectively solve this problem that serious lack of labor and tillage facing enormous challenges in the hilly areas, and improves the level of the agricultural mechanization of the hilly area. The vibration intensity is large when mini tiller is operating, in the farming season, the operators are susceptible to vibration disease for a long time operate. At present the vibration research of mini tiller vibration is relatively few, so researching the vibration characteristics of mini tiller, not only expands the field of research on mini tiller, also can provide reference that the vibration research of other small agricultural machinery.In this paper, a common mini tiller was taken as the research object, mini tiller vibration data acquisition and analysis system was created based on LabVIEW, the vibration signals of key components was tested when mini tiller under different conditions, the vibration signals was analyzed in time domain and frequency domain. ANSYS was utilized to the modal analysis of handle and LMS test.lab was utilized to free modal experiment, to determine the relationship between the inherent frequency of handle and the vibration frequency of engine and blade roller. The method of reduce the vibration of mini tiller was discussed based on the test results and simulation resultsThe vibration signals of mini tiller was analyzed in time domain and frequency domain, the results show that the average difference of left and right handle’s vibration under different conditions is 8.6%, the vibration intensity is basically coincident. Before-and-after vibration of engine under all conditions have the minimum, the main vibration of engine under all conditions is up-and-down vibration and left-and-right vibration; the structure and stiffness of gearbox is reasonable. The up-and-down vibration of handle has the maximum when mini tiller is under the no-operating, but before-and-after vibration of handle has the maximum, up-and-down vibration of handle takes second place, and left-and-right vibration of handle has the minimum when mini tiller was operating. Mini tiller is not suitable for tillage when engine is operating at high speed, in order to meet the requirements of farming, the mini tiller should run under relatively small conditions by adjusting throttle; The vibration frequency components of the handle and engine are basically same, the first order inertia force excitation frequency of engine has the maximum contribution for handle’s vibration.The results of handle free modal analysis and modal experiment was contrasted, the average relative error of the two inherent frequency is 5.06% and vibration modes is coincident, so the finite element model of handle is right. The low order inherent frequency and vibration mode of handle’s actual vibration was obtained by constraint modal analysis of handle. To avoiding handle come out resonance, the inherent frequency of handle should be changed by optimized the structure of handle.The experiment results and simulation results indicated that the vibration source of mini tiller’s handle mainly comes from engine. The reason of handle come out resonance is that the frequency components of the handle’s vibration and the low order inherent frequency of handle under constraint is close-by, handle is like a cantilever beam and the stiffness of handle is finite, the free end of handle is not binding.