插装式电液比例流量放大阀特性分析

插装阀具有通流量大、结构简单和成本低等优点,广泛应用于液压系统中。笔者针对一种主级基于流量放大原理、先导级采用单级伺服比例方向阀的两级插装比例节流阀特性进行分析,建立了该比例节流阀的简化数学模型,获得了简化条件下的特性关系式。以此为基础,在SimulationX软件环境中建立该液压阀的仿真模型,利用实验数据对模型正确性进行验证,运用验证后的仿真模型对比例阀性能特性进行分析。结果表明:该液压阀输出流量静态特性存在死区,阶跃响应存在时间滞后,主阀流量放大倍数并不是常数,性能影响因素与主阀反馈槽预开量、面积梯度、级间过渡容腔体积以及先导阀通流能力等相关。

Characteristics of electro-hydraulic proportional cartridge inserted valve based on flow amplifier

Cartridge inserted valves are widely used in hydraulic applications because of their large flow capacities, simple structure and low cost. In this paper, a two-stage cartridge inserted proportional throttle valve was investigated. The main stage of the two-stage poppet type proportional throttle valve is based on flow amplification principle, and a single-stage servo proportional direction valve is used in its pilot stage. We first established a simplified mathematical model, and obtained the qualitative expressions under simplified conditions. Then, we set up a simulation model of the proportional throttle valve by means of SimulationX, and verified the correctness of the model with experimental data. Finally, we used the verified simulation model to analyze the performance of the proportional throttle valve. The results show that there is a dead zone and time lag of the output flow and the flow gain of the main stage is variable. The performance of the proportional throttle valve is affected by the underlap and the area gradient of the feedback slot, the volume between the pilot and the main stages, and flow capacity of the pilot stage, etc.