论文部分内容阅读
本文通过对工业缝纫机的模态参数识别,把工业缝纫机在正常转速下的振动简化为刚体在水平面内的振动,建立其数学模型,利用光电传感器拾取缝纫机转轴上某一基准点运动的周期信号,同时拾取机头上A、B两点振动加速信号,通过自谱及互谱分析和换算,求得机头上A、B两点振动位移的幅值和相对于基准点的相位,并认为该振动信号的某阶谐波分量是由具有同频率转速的转轴上作用的动不平衡力和力矩所引起。这样,通过适当的运算,即求得正常转速时上轴和下轴作用的动不平衡力、力矩的大小和相位,它是各种激励力作用的综合结果。
Based on the modal parameter identification of industrial sewing machine, this paper simplifies the vibration of industrial sewing machine at normal speed to the vibration of rigid body in horizontal plane, establishes its mathematical model, picks up the periodic signal of the movement of a certain reference point on the rotating shaft of sewing machine by using photoelectric sensor, At the same time, pick up the vibration acceleration signals of A and B on the head, and through the analysis and conversion of spectrum and cross spectrum, find the amplitude of vibration displacement and the phase relative to the reference point of A and B on the nose, The first harmonic component of the vibration signal is caused by the unbalanced forces and moments acting on the rotating shaft with the same frequency rotation speed. In this way, through proper calculation, that is, the normal unbalance force, torque magnitude and phase of the upper shaft and the lower shaft at the normal speed are obtained, which is the result of various stimulating forces.