关于VVT噪声改善方法的研究

Study on the Ways to Improve the NVH Performance of VVT

本文主要研究了发动机VVT正常工作过程中的噪声和改善方法,并通过试验验证了对应方案的改进结果;得到以下结论:(1)整体式转子可以有效改善冷机启动和怠速敲击噪声;(2)定转子缓冲槽,缓冲槽中机油可以减缓撞击,减少敲击噪声(3)减小锁销间隙可以改善敲击噪声;(4)缸盖上供VVT机油的油路上增加单向阀,减缓机油泄露,能够显著提升冷起动NVH性能;(5)其他方法如更换卷簧模态、转子叶片油路开度、定转子接触叶片数等可以改善VVT噪声。

The ways to improve the NVH performance of variable valve timing are introduced. The influence of these ways on VVT noise is verified based on tests. The results show that:(1) Integral type VVT can improve the knocking noise under cold starting and idling effectively;(2) The stator and rotor with buffer grooves has obvious effect on reducing impact energy and noise.(3) Reducing the lock pin clearance can improve the knocking noise;(4) Adding one-way valve on the oil path of VVT on the cylinder head can slow down oil leakage. The cold starting noise can be effectively improved.(5) The VVT noise can be improved by other methods, such as changing coil spring modal, oil passage opening of rotor, stator and rotor contact blades number, etc.