轴向柱塞泵配流副油膜试验原理及控制特性

为研究油、水介质下轴向柱塞泵几类关键摩擦副的润滑特性，提出采用电液单元对润滑油膜进行主、被动控制的专用试验系统原理。论述该试验系统用油膜厚度反馈控制配流副密封间隙的模拟试验装置的原理与构成，将微缝隙流对电液控制系统的作用简化为弹簧中阻尼器负载，建立配流副对润滑油膜厚度的阀控缸物理模型并推导精密缸位移控制方程，分析影响润滑性能的主控参量及相互关系，仿真研究油膜厚度控制的动态特性。运用该试验系统进行了初步的平面配流副油膜试验。研究表明，油膜平衡的仿真与试验基本一致，供油压力、摩擦转矩等对润滑油膜的形成影响较大。伺服比例阀的反馈控制原理使系统的油膜厚度动态反馈性能趋于稳定，但在供油压力斜坡变化时油膜厚度平衡值在设定范围内有一定变化。

Principle of Oil Film Test on Port Pair of Axial Piston Pump and Control Characteristics

In order to study the lubrication characteristics of several key friction pairs in axial piston pump under oil or water medium, the principle of the specialized test system that adopts electrohydraulic units for active and passive control of the lubricating oil film is proposed. The principle and constitution of the simulation test system of the said test system that uses film thickness feedback to control the sealing gap of port plate pair is discussed. The action of micro gap flow on the electrohydraulic control system is simplified to the load on the damper in spring, the physical model of the valve-controlled cylinder of port plate pair in relation to the lubricating film thickness is established, and the precision cylinder displacement control equation is derived. The main control parameters affecting the lubrication performance and their interrelations are analyzed, and the dynamic characteristic of film thickness control is simulated. The preliminary test of planar port plate pair oil film is carried out by using the test system. The results show that the simulation of oil film equilibrium is basically consistent with the test, and oil supply pressure and friction torque have relatively great effect on the formation of lubricating oil film. The feedback control principle of servo proportional valve makes the system’s film thickness dynamic feedback performance tend to keep stable, but when the slope of oil supply pressure varies, the equilibrium value of film thickness has certain variation within the preset range.