【摘要】 为了适应切割大尺寸、粘性食品的要求,设计了频率为20k Hz的食品用超声切割刀。采用有限单元法对其进行模态分析,获取各阶固有频率、刀具刃口振幅分布等参数。通过对切割刀刀身结构进行敏感性分析,得到了切割刀结构尺寸对切割刀输出端位移的均匀性、纵向振动固有频率与邻近频率的影响。对影响程度大的结构参数进行了二次优化,使所设计的切割刀在20k Hz频率附近以纵向振动模式为主,谐振频率与邻近固有频率间距足够大,刃口振幅位移分布均匀性得到较大的提高。更多还原

【Abstract】 An ultrasonic cutter of 20 k Hz for food is designed to meet the demand of cutting large viscoelastic food. By analyzing its model with the finite element method, the natural frequencies of all orders and the distribution of displacement amplitude of cutter edge are obtained. The influence of the structure size on the uniformity of displacement at the output port, the longitudinal natural frequency of vibration and the adjacent frequency are analyzed. The structural parameters with high sensitivities are redesigned to make the cutter dominated by the longitudinal vibration near 20 k Hz. The interval between the resonant frequency and the natural frequencies is large enough, and the distribution of displacement amplitude on the cutting edge surface is greatly improved.更多还原