摘要
为了解决混凝土泵摆动系统中恒压变量泵的瞬时吸空问题,对摆动系统的工况特点及吸空机理进行分析,发现在变量泵排量增大的初始阶段,由变量泵输出流量的快速变化引起吸油腔中油液压力的波动,是导致恒压变量泵发生瞬时吸空的主要原因。通过对恒压变量泵进行数学建模并采用AMESim进行仿真研究,提出了一种在变量缸敏感腔进油口处设置比例节流阀以控制流量变化率的方法,由变量缸的位移信号控制节流阀的开度,对变量缸的流量及运动速度进行调节,从而实现对变量泵流量的控制。对恒压变量泵原始状态条件、设置单向阻尼孔及设置比例节流阀时的工作过程作AMESim仿真及试验研究。研究结果表明:设置1.35mm单向阻尼孔和设置比例节流阀2种改进方案都能基本消除吸空现象,其中设置比例节流阀时恒压变量泵吸油腔压力基本保持略大于空气分离压,且斜盘倾角升程时间为35ms,虽然相对于原始条件下的响应时间(31ms)延长了13%,但其相对于设置1.35mm单向阻尼孔时的响应时间(40ms)则有较大降低;设置比例节流阀在保证恒压变量泵流量效率的同时基本消除了瞬时吸空现象,对提高混凝土输送泵的使用可靠性及工作效率具有重要意义。
To solve the problem of instantaneous air suction of constant pressure variable displacement pump of swing system, the working features of swing system and the principle of air suction were investigated. It was discovered that the major cause for instantaneous air suction is the instantaneous pressure fluctuation of oil in the oil absorption cavity resulted from the rapid change of the output flow during the initial time when the pump changes its displacement. With the establishment of mathematical model and simulation of pump in AMESim, a novel method was proposed to control the flow change rate by setting proportional throttle valve at oil inlet of variable cylinder sensitive cavity. By controlling the throttle opening according to the displacement of variable cylinder, flow and displacement of variable cylinder were adjusted so as to realize the control of flow of the pump. AMESim simulation and experiment research wereconducted on the working process of the pump in the state of origin, setting one-way orifice and setting proportional throttle valve. The results show that two methods of setting 1.35 mm one- way orifice and setting proportional throttle valve can both eliminate the phenomenon of air suction basically. The oil pressure in oil absorption cavity of pump stays a little higher than over the air separation pressure in the state of setting proportional throttle valve. In addition, the time of swashplate angle raising is 35 ms. Even though that time is extended by 13% compared with the time （31 ms） in the state of origin, it is greatly less than the time （40 ms） in the state of setting 1.35 mm one-way orifice. Therefore, the method could guarantee the flow efficiency of pump and eliminate the phenomenon of air suction basically, which is of great significance to improve the reliability and efficiency of swing system.
作者
胡军科
赵斌
蒋亚军
段小龙
HU Jun-ke ZHAO Bin JIANG Ya-jun DUAN Xiao-long(School of Mechanical and Electrical Engineering, Central South University, Changsha 410012, Hunan, China)
出处
《长安大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2016年第5期118-126,共9页
Journal of Chang’an University(Natural Science Edition)
基金
国家自然科学基金项目(51305463)
关键词
机械工程
恒压变量泵
瞬时吸空
比例节流阀
流量变化率
AMESIM
mechanical engineering
constant pressure variable displacement pump
instantaneousair suction
proportional throttle valve
flow change rate
AMESim
