冲模振动噪声分析

Noise Research Based on Vibration in Punching Dies

分析高速旋转压片机的冲模在主压时工作状况,以及所受的周期性作用力。高速旋转压片机的噪声主要由于冲模的振动产生的。把主压时片芯和下冲模当作一根做轴向振动的复合棒,这根复合棒受到周期性作用力作用,发生周期性振动,产生周期性噪声。结合下冲模和片芯的性质,利用复合棒振动的边界条件,写出复合棒的各段近似振动方程,由振动方程写出冲模的辐射噪声声场的声压方程,通过试验值与仿真值比较来验证该模型的合理性和可行性。

The noise of a high-speed rotary tablet press machine is caused by the vibration in dies. The working condition of dies is analysed during the main pressing. There is a periodical force exerted on a couple of dies. It is regarded as the vibration of a compound stick in longitudinal direction. The compound stick , which is made up of tablet core and down-punch, takes place periodical vibration and periodical noise. The vibration equations are deduced by the nature of dies and tablet cores and the boundary condition of the compound sticks. The equations of the noise acoustic pressure is also deduced by the vibration equations of dies. The rationality and the feasibility of the model is verified by both the experimental value and the simulation value.