重型拖拉机全独立式悬浮转向驱动桥液压系统设计研究

Design and research on hydraulic system of fully independent and suspended steering axle for heavy tractor

为解决拖拉机传统驱动桥与整机刚性连接带来的震动和颠簸问题,改善拖拉机在崎岖道路上的驾驶平稳性和安全性,提高作业的质量和效率,设计重型拖拉机全独立式悬浮转向驱动桥的液压系统。该系统采用负载敏感变量柱塞泵,兼用于本液压控制系统和主机工作系统,从而降低产品成本;采用电磁阀组适时精量控制进出悬浮油缸液压油量从而达到调节支撑刚度的目的。重点介绍该液压系统的结构组成、元件选型、工作原理分析以及试验验证。试验结果表明,该全独立式悬浮转向驱动桥性能良好,液压系统稳定可靠,各动作反应灵敏,3 h系统温升72℃、最大静态压力13.8 MPa、最大悬浮高度95 mm、回油背压1.5 MPa,各项检测值均满足设计指标要求。本液压系统的设计为重型拖拉机全独立式悬浮转向驱动桥的研发提供技术支撑,并填补国内同类技术空白。

In order to solve the problems of vibration and turbulence caused by the rigid connection between the traditional driving axle and the tractor,improve the stability and safety of the tractor on the rough road,and improve the quality and efficiency of the operation,the hydraulic control system of the tractor’s fully independent and suspended steering axle was designed.The system adopted the load-sensitive variable displacement pump,which was also used in the hydraulic control system and the main engine operating system to reduce the product cost.The solenoid valve set was also used to precisely control the hydraulic oil in and out of the suspended cylinder at the right time so as to achieve the purpose of adjusting the stiffness of the support.In this paper,the structure,component selection,working principle analysis and tests of the hydraulic system were introduced emphatically.Test results showed that performance of tractor’s fully independent and suspended steering axle was good,the hydraulic system was stable and reliable,and the action response was sensitive.The temperature rise of the 3 h system was 72℃,the maximum static pressure was 13.8 Mpa,the maximum suspension height was 95 mm,and the back pressure of returning oil was 1.5 Mpa,all of which could meet the design requirements.At the same time,the design of the system provided technical support for the research and development of fully independent and suspended steering axle of the heavy-duty tractor,and could fill the technical gap in this field at home.