某叉车方向盘振动舒适性诊断及优化

Diagnosis and optimization of vibration comfort of a fork-lift steering wheel

针对某新型内燃叉车在怠速工况下出现方向盘振动过大导致舒适性较差的问题,以该款叉车试验车为对象,研究从发动机到方向盘的振动传递情况,通过TPA(Transfer Path Analysis,TPA)传递路径试验确定叉车方向盘振动峰值频率,通过TPA传递路径分析确定发动机各悬置对方向盘的振动贡献量以及各条路径对方向盘振动的影响,确定该叉车方向盘振动过大舒适性差的原因是发生了共振。为了验证,对方向盘进行约束模态试验,得到的方向盘约束模态频率与振动峰值频率吻合。最后通过方向盘结构优化改变方向盘约束模态频率避免共振,基于ISO-5349进行方向盘手传振动舒适性评价,振动舒适性得到明显改善,有效解决了问题。

Aiming at the problem that the steering wheel of a new-type fork lift truck vibrates too much under the idle condition,we studied the vibration transmission from the engine of the fork lift truck to its steering wheel.The peak vibration frequency of the steering wheel was determined by TPA test.Then the contribution of each mounting of the engine to the steering wheel vibration and the influence of each path on the steering wheel vibration were determined.It was suggested that the excessive vibration of the steering wheel was caused by resonance.In order to verify the hypothesis,we carried out constrained modal test on the steering wheel.The obtained constrained modal frequency of the steering wheel coincided with the peak vibration frequency,which proved that the excessive vibration of the steering wheel was caused by resonance.The steering wheel structure was optimized to avoid resonance.We evaluated the vibration comfort based on ISO-5349,and confirmed that the vibration comfort was significantly improved.