Handheld Micro tiller time-frequency characteristic and vibration isolation measures

Abstract

The handheld micro tiller is a typical small agricultural machine. It vibrates severely during the rotary tillage process, which harms the users’ health. It is necessary to study its vibration characteristics and propose vibration isolation measurements. Firstly, the external forces applied on various components of the micro-tiller were analyzed. The main components of the handheld micro tiller were simplified. And then the micro-tiller vibration model was built. The time-frequency domain characteristics of the micro-tiller were analyzed. The main components’ RMS values were calculated. It shows that the excitation force of the engine is the main source of vibration of the micro-tiller. The simulated RMS values of the frame and the gearbox were compared to the tested values. The errors indicate the established model is to some extent reasonable. In order to reduce the vibration transmitted to the handrail, firstly, the ordinary bolts connecting the engine and the frame were replaced with rubber bolts. And then the RMS value was analyzed and calculated. The results showed that this method could not effectively reduce the vibration of other main components. Furthermore, it is considered to install a vibration isolator between the engine and the frame of the tiller. Time-frequency domain simulation results show that after adding the vibration isolator, the vibration RMS value of each component was much smaller than before. It shows that it isolates the engine vibration effectively. The research in this paper laid the foundation for designing a reasonable vibration isolator and reducing the vibration of the main components of the tiller.