关键词: 车辆动力装置, 变刚度, 隔振, 稳定性

Abstract: The conventional vibration isolation system of vehicle power packs might not guarantee both of the low-frequency vibration isolation performance and high load-bearing stability. New methods and new technologies were urgently demanded to achieve the unity of them. The influences of the stiffness in different regions on the isolation performance and stability were analyzed, and a novel isolation configuration was proposed, which consisted of preloaded constant spring with variable spring in parallel. Design method of the proposed variable vibration isolators was illustrated, where the stiffnesses and preloads of constant spring were determined based on vibration isolation ratio and payload, and parameters of variable spring were optimized based on stability requirements. The new vibration isolator has high payload capacity and wide frequency domain of vibration isolation, and particularly, the isolation performance in low-frequency working domain is significantly improved. Experimental results on a new special vehicle by adopting the proposed vibration isolation system show that, besides guarantee of sufficient stability, the vibration isolation ratio is increased from 30.3% to 83.5% under rated working conditions.

Key words: vehicle power pack, variable stiffness, vibration isolation, stability