共查询到20条相似文献,搜索用时 15 毫秒
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本文提出了新型的恒流柱塞泵的理论分析和设计,针对柱塞泵的运动情况,阐述了为实现柱塞泵的无流量脉动的柱塞的运动速度曲线所必须具备的特征,导出了几种常见的恒流特征速度曲线,并设计了径向恒流柱塞泵。 相似文献
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Driving a hydraulic cylinder directly by a closed-loop hydraulic pump is currently a key research area in the field of electro-hydraulic control technology,and it is the most direct means to improve the energy efficiency of an electro-hydraulic control system.So far,this technology has been well applied to the pump-controlled symmetric hydraulic cylinder.However,for the differential cylinder that is widely used in hydraulic technology,satisfactory results have not yet been achieved,due to the asymmetric flow constraint.Therefore,based on the principle of the asymmetric valve controlled asymmetric cylinder in valve controlled cylinder technology,an innovative idea for an asymmetric pump controlled asymmetric cylinder is put forward to address this problem.The scheme proposes to transform the oil suction window of the existing axial piston pump into two series windows.When in use,one window is connected to the rod chamber of the hydraulic cylinder and the other is linked with a low-pressure oil tank.This allows the differential cylinders to be directly controlled by changing the displacement or rotation speed of the pumps.Compared with the loop principle of offsetting the area difference of the differential cylinder through hydraulic valve using existing technology,this method may simplify the circuits and increase the energy efficiency of the system.With the software SimulationX,a hydraulic pump simulation model is set up,which examines the movement characteristics of an individual piston and the compressibility of oil,as well as the flow distribution area as it changes with the rotation angle.The pump structure parameters,especially the size of the unloading groove of the valve plate,are determined through digital simulation.All of the components of the series arranged three distribution-window axial piston pump are designed,based on the simulation analysis of the flow pulse characteristics of the pump,and then the prototype pump is made.The basic characteristics,such as the pressure,flow and noise of the pumps under different rotation speeds,are measured on the test bench.The test results verify the correctness of the principle.The proposed research lays a theoretical foundation for the further development of a new pump-controlled cylinder system. 相似文献
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The limit working parameters and service life of axial piston pump are determined by the carrying ability and lubrication characteristic of its key friction pairs. Therefore, the design and optimization of the key friction pairs are always a key and difficult problem in the research on axial piston pump. In the traditional research on piston/cylinder pair, the assembly relationship of piston and cylinder bore is simplified into ideal cylindrical pair, which can not be used to analyze the influences of radial micro-motion of piston on the distribution characteristics of oil-film thickness and pressure in details. In this paper, based on the lubrication theory of the oil film, a numerical simulation model is built, taking the influences of roughness, elastic deformation of piston and pressure-viscosity effect into consideration. With the simulation model, the dynamic characteristics of the radial micro-motion and pressure distribution are analyzed, and the relationships between radial micro-motion and carrying ability, lubrication condition, and abrasion are discussed. Furthermore, a model pump for pressure distribution measurement of oil film between piston and cylinder bore is designed. The comparison of simulation and experimental results of pressure distribution shows that the simulation model has high accuracy. The experiment and simulation results demonstrate that the pressure distribution has peak values that are much higher than the boundary pressure in the piston chamber due to the radial micro-motion, and the abrasion of piston takes place mainly on the hand close to piston ball. In addition, improvement of manufacturing roundness and straightness of piston and cylinder bore is helpful to improve the carrying ability of piston/cylinder pair. The proposed research provides references for designing piston/cylinder pair, and helps to prolong the service life of axial piston pump. 相似文献
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该文设计了一套航空柱塞泵运行状态监测系统,介绍航空柱塞泵模拟试验台工作原理及监测系统设计思路,运用PLC控制系统采集与处理航空柱塞泵运行状态关键参数,利用Lab VIEW软件实现相关数据的分析与实时显示,结合OPC技术,实现了PLC与LabVIEW间的数据通信,进行航空柱塞泵运行状态参数监测,对保障航空柱塞泵安全稳定运行具有重要意义。 相似文献
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Flow Ripple of Axial Piston Pump with Computational Fluid Dynamic Simulation Using Compressible Hydraulic Oil 总被引:1,自引:1,他引:0
MA Ji'en XU Bing ZHANG Bin YANG Huayong 《机械工程学报(英文版)》2010,23(1):45-52
The flow ripple, which is the source of noise in an axial piston pump, is widely studied today with the computational fluid dynamic(CFD) technology development. In the traditional CFD modeling, the fluid compressibility, which strongly influences the accuracy of the flow ripple simulation results, is often neglected. So a compressible sub-model was added with user defined function(UDF) in the CFD model to predict the flow ripple. At the same time, a test rig of flow ripple was built to study the validity of simulation. The flow ripple of pump was tested with different working parameters, including the rotation speed and the working pressure. The comparisons with experimental results show that the validity of the CFD model with compressible hydraulic oil is acceptable in analyzing the flow ripple characteristics. In this paper, the improved CFD model increases the accuracy of flow ripple rate to about one-magnitude order. Therefore, the compressible model of hydraulic oil is necessary in the flow ripple investigation of CFD simulation. The compressibility of hydraulic oil has significant effect on flow ripple, and the compression ripple takes about 88% of the total flow ripple of pump. Leakage ripple has the lowest proportion of about 4%, and geometrical ripple leakage ripple takes the remnant 8%. Besides, the influence of working parameters was investigated through the CFD simulations and experimental measurements. Comparison results show that the amplitude of flow ripple grows with the increasing of rotation speed and working pressure, and the flow ripple rate is independent of the rotation speed. However, flow ripple rate of piston pump grows with the increasing of working pressure, because the leakage ripple will increase with the pressure growing. The investigation on flow ripple of an axial piston pump using compressible hydraulic oil provides a more validity simulation model for the CFD analyzing and is beneficial to further understanding of the flow ripple characteristics in an axial piston pump. 相似文献
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Qun CHAO Jianfeng TAO Junbo LEI Xiaoliang WEI Chengliang LIU Yuanhang WANG Linghui MENG 《Frontiers of Mechanical Engineering》2021,16(1):176-185
The power density of axial piston pumps can benefit greatly from increased rotational speeds. However, the maximum rotational speed of axial piston machines is limited by the cavitation phenomenon for a given volumetric displacement. This paper presents a scaling law derived from an analytical cavitation model to estimate the speed limitations for the same series of axial piston pumps. The cavitation model is experimentally verified using a high-speed axial piston pump, and the scaling law is validated with open specification data in product brochures. Results show that the speed limitation is approximately proportional to the square root of the inlet pressure and inversely proportional to the cube root of volumetric displacement. Furthermore, a characteristic constant Cp is defined based on the presented scaling law. This constant can represent the comprehensive capacity of axial piston pumps free from cavitation. 相似文献
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柱塞泵的合理使用与故障分析 总被引:3,自引:3,他引:0
本文根据对冶金液压设备中柱塞泵应用实践与研究,提出合理使用柱塞泵的基本原则,对柱塞泵常见故障产生的原因、排除方法进行了分析,以利于柱塞泵研究设计、生产制造、使用维护者提高柱塞泵的技术性能,对故障进行预防、诊断与排除。 相似文献
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对轴向柱塞泵产生松靴故障的机理进行分析.选取振动信号和油液温升信号作为监测参量.分析研究表明,泵壳体振动信号和外泄口油液的温升信号是轴向柱塞泵松靴故障的敏感特征参量. 相似文献
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Il-Hyun Baek Ihn-Sung Cho Jae-Youn Jung Lu Hong 《Journal of Mechanical Science and Technology》2008,22(9):1726-1733
To improve the performance of the bent-axis type axial piston pump driven by the tapered piston, it is necessary to know the
driving characteristics and mechanism of the tapered piston and the cylinder block. Since each piston not only rotates on
its axis and reciprocates in the cylinder bore but also revolves around the axis of the driving shaft, it is difficult to
analyze the driving mechanism theoretically. The theoretical mechanism for the bent-axis type axial piston pump is studied
by using the geometrical method. The driving range of the tapered piston is determined by theoretical equations. The results
show that the cylinder block is driven by one tapered piston in a limited range and the core parameters such as the tilting
angle of the piston and the ahead delay angle influence performance of the bent-axis type axial piston pump. 相似文献
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In this study, the lubrication characteristics of a slipper bearing for axial piston pump considering oil thermal effect have been investigated. A mathematical model is developed to predict the film thickness and temperature on the slipper/swash plate interface under different operating conditions. Based on the mathematical model, a parametric study is conducted to evaluate the slipper lubrication performance. It is found that the slipper is characterised by an unstable behaviour and the behaviour is enhanced by lower pressure and higher rotational speed. As the film temperature increases rapidly due to high shaft speed and piston chamber pressure, the overall result is a rather low decline in the film thickness. The leakage flow rate increases with increasing speed or oil film thickness. The structure parameter can be optimised to obtain satisfactory slipper performance. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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新型径向柱塞泵摩擦副泄漏原因分析与改进 总被引:3,自引:1,他引:2
该产品在首次试验时由于泄漏量偏大,造成性能下降,针这对一问题,文中对主要泄漏的四对密封摩擦副进行了分析与改进,并提出了理论依据及改进前后试验数据,从而使产品达到了性能要求,顺利地通过试验。 相似文献