| ABSTRACT:Every year, large amounts of abandoned twigs are generated in the municipal landscaping. Traditionally, the twigs are disposed in the landfill or by incineration like other urban solid waste. These cause not only a waste of resources but also serious environmental pollution. Processing method of modernization is to cut these twigs into chips, which can be as the mulching material or be made into organic fertilizer. However, it’s difficult to see mobile twig chipper which is suitable for city operation in the domestic market, the reason is that the domestic haven’t mastered its design theory. The key technical problems urgently need addressing.The result of this paper is to research and design a twig chipper, which has small volume and noise, can cut the twig whose diameter is less than or equal to100mm and get the chip which is less than or equal to20mm.By establishing the twig cutting force model, combining with the present cutting theory, the theory of continuous cutting is put forward. On the basis of continuous cutting theory, the cutting mechanism is designed. This paper constructs3D model of key parts of twig chipper, and assembles all the parts, and does the interference checking by using3D modeling software.In this paper, the key parts are analyzed by finite element method. A coMParative dynamitic analysis is performed between the new cutting mechanism and the ordinary mechanism, which verifies the rationality and superiority of the continuous cutting theory; through static structural analysis of key parts, to verify if the parts can meet the strength and stiffness requirements; in order to avoid mechanical resonance, the dynamic analysis of bearing-rotor system is done. The analysis results show the twig chipper has low vibration, small noise and the advantage of continuous cutting. This paper can provide useful reference for twig chipper autonomy research. |
