Authors

Abstract

Aiming at the problems of large vibrations and noise of a working stalk rubbing machine, this paper took the 9R-60 rubbing machine as the research object and used the B&K modal test system and the vibration test system to analyse the modal and no-load conditions of the whole machine. Through analysing modal test data, it was concluded that the first five natural frequencies of the machine were 95.262 Hz, 144.386 Hz, 288.198 Hz, 313.719 Hz and 326.140 Hz. The results showed that spindle rotation had a more significant effect on the vibration than the feed chain rotation; the maximum vibration acceleration occurred at the small motor frame at a spindle speed of 1700 r·min-1 and a feed chain speed of 0.65 m·s-1, which was 135.539 m·s-2. The distribution of the amplitude statistical characteristics of the vibration signals follows the normal distribution and belongs to the stationary random process. The vibration was a self-excited vibration of the rotating machinery caused by the rotation of the main shaft and a forced vibration excited by the rotation of the same shaft. The research provides a direction for further research on the vibration characteristics of the rubbing machine under load conditions, and provides a theoretical basis for the subsequent vibration reduction design.

Abstract in Chinese

针对工作状态下揉碎机振动大、噪声大的问题，以9R-60揉碎机为研究对象，采用B&K模态测试系统与振动测试系统对其模态与空载工况进行分析。通过对模态试验数据的分析，得出其前五阶固有频率分别为95.262 Hz、144.386 Hz、288.198 Hz、313.719 Hz和326.140 Hz。结果表明，主轴转动相比于喂入链转动对揉碎机振动的影响更为明显；在主轴转速1700 r·min-1、喂入链转速0.65 m·s-1时，小电机机架振动加速度最大，为135.539 m·s-2。振动信号的幅度统计特性分布服从正态分布，属于平稳随机过程。振动是由主轴旋转引起的旋转机械的自激振动和同轴旋转激发的强迫振动。该研究为进一步研究摩擦机在载荷条件下的振动特性提供了方向，并为后续的减振设计提供了理论依据。