WY60挖掘机液压系统的分析与仿真研究
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摘要
小型全回转履带式液压挖掘机以它所独具的小巧、灵活、多功能、高效率以及低价格、维修方便等特点备受愈来愈多的小型化上方施工单位的喜爱。液压系统作为液压挖掘机的重要组成部分,如何充分利用发动机功率,降低能量损失,是单斗液压挖掘机需要解决的重要课题,所以对液压系统进行仿真,不但可以预测机器的性能、缩短产品的设计周期,而且还可以对整个系统的性能进行评估。
本文采用液压仿真软件AMESIM对系统进行仿真。通过分析其工作状态下的各项性能,优化液压系统配置,改进整机性能,并实现最大程度的节能。
本文分析了液压系统的结构组成和基本回路工作原理,对挖掘机的液压系统进行了设计计算。根据整机性能要求,在对’原液压系统进行深入分析研究基础上,提出并进行了如下创新性的技术改进：(1)为了减小液压冲击,在设计行走马达时,增加了无冲击的安全阀,并对改进后的液压元件的特点做了分析；(2)本机所采用的全功率控制系统,分析了不二越全功率控制液压系统的特点与特性分析,对挖掘机的液压泵的功率匹配进行了计算与验证,满足全功率控制的目的；(3)对工作装置在各种工况下的循环时间、闭锁力等参数进行计算和液压缸的强度与稳定性进行了验算；(4)根据设计好的液压系统原理图,建立了小挖的阀控液压缸、负载敏感泵、回转系统、行走系统与整机液压系统的仿真模型。
在设计系统之前,根据整机所要达到的技术要求,对系统进行了整体的优化。为了达到全功率控制的目的,实现各种工况下的动作切换,增加了主泵的功率切换功能,为了安装的方便,减小了主泵的长度,缩短了7-11mm,泵的最大排量增加了6m1/r,保证了性能的稳定性。为了使行走马达的回转体积减小,将液压马达、液压阀和减速机设置成一体,提高减速机的材料强度以用来增强液压马达的承受力。为了能使回转马达安装在驾驶室底下,改变了零部件的装配,降低高度为20%。
通过对改进后的液压系统进行AMESIM仿真,可得到行走马达的输出轴转速更稳定、进出口压力曲线在出现瞬时峰值后,保持稳定,即可保证了挖掘机行走的直线性；通过仿真看到传统回转系统的缺点与不二越回转系统的优点,表明后者的效率提高了、马达进出口压力稳定了。在对整个液压系统的仿真,研究表明,液压系统的功率曲线与发动机的功率曲线基本吻合,在最大程度上满足了全功率控制的目的。从而验证了利用AMESIM软件创建系统的正确性、合理性与参数设置的正确性。
As its unique compact, flexible, multi-function, high efficiency and low price, easy maintenance, mall entire rotation crawler excavator is becoming more and more small earthwork construction units'favorite. Hydraulic system works as an important part of hydraulic excavator, How to make full use of engine power, reduce energy loss of hydraulic excavator is an important issue to be resolved, so doing research of simulation of the hydraulic system, not only can predict the performance of the machine, shorten product design cycle, but can also evaluate the performance of the entire system.
In this paper, I use AMESIM hydraulic simulation software to simulate the system. By analyzing the condition of their working performance, we can optimize the hydraulic system's configuration, improve the overall perfonnance and achieve maximum energy efficiency.
This paper analyzes the structure and components of the hydraulic system and basic principle of circuits, calculating and designing the excavator's hydraulic system. Under the overall performance requirements, on basis of the original depth analysis of the hydraulic system, the following proposed and the innovative technical improvements are as follows:(1) In order to reduce the hydraulic shock, I the increased security without impact valves in designing the motor running, and analyzed the characteristics of the improved hydraulic components; (2) the machine applies full power control system, analyzes Fujio full power control features and characteristics of hydraulic system analysis, calculates and verifies the power matching of the excavator's hydraulic pump in order to meet the full power control purposes; (3) calculated working devices'parameters of the cycle time, blocking force, etc. in various conditions; checking the cylinders'strength and stability:(4) According to the completed schematic diagram of hydraulic system, established mini excavator's cylinder valve, load sensing pump, rotary system, travel system as well as simulation model of the machine hydraulic system.
Before designing the system, I optimized the overall system according to the technical requirements of the overall system. In order to achieve full power control purposes and realize the action switches in a variety of conditions. I increased the switching function in main pump; for the purpose of easy installation. I reduced the length of the main pump and made it 7～11mm shorter, increased by 6ml/r in pump maximum discharge, to guarantee performance's the stability. In order to reduce the size of the rotary motor running, I set the hydraulic motors, hydraulic valves and gear as integration, improved the material strength of gear so as to enhance the affordability of the hydraulic motor. For the purpose of putting the rotary motor mounted under the cab, I changed the assembly of parts, reducing the height to 20%.
Through the improved hydraulic system AMESIM simulation, available walking speed of the motor output shaft is more stable, import and export in the event of transient pressure curve after the peak, remained stable, you can ensure the linearity of excavator; the simulation to see The shortcomings of the traditional rotation system and the advantages of rotary system Fujio, that improves the efficiency of the latter, import and export of motor pressure stable. In the hydraulic system, research shows that the hydraulic system of the engine power curve and power curve are consistent, to the maximum extent to meet the full power control. To verify the system using software to create AMESIM correctness, rationality and parameter settings are correct.
本文采用液压仿真软件AMESIM对系统进行仿真。通过分析其工作状态下的各项性能,优化液压系统配置,改进整机性能,并实现最大程度的节能。
本文分析了液压系统的结构组成和基本回路工作原理,对挖掘机的液压系统进行了设计计算。根据整机性能要求,在对’原液压系统进行深入分析研究基础上,提出并进行了如下创新性的技术改进：(1)为了减小液压冲击,在设计行走马达时,增加了无冲击的安全阀,并对改进后的液压元件的特点做了分析；(2)本机所采用的全功率控制系统,分析了不二越全功率控制液压系统的特点与特性分析,对挖掘机的液压泵的功率匹配进行了计算与验证,满足全功率控制的目的；(3)对工作装置在各种工况下的循环时间、闭锁力等参数进行计算和液压缸的强度与稳定性进行了验算；(4)根据设计好的液压系统原理图,建立了小挖的阀控液压缸、负载敏感泵、回转系统、行走系统与整机液压系统的仿真模型。
在设计系统之前,根据整机所要达到的技术要求,对系统进行了整体的优化。为了达到全功率控制的目的,实现各种工况下的动作切换,增加了主泵的功率切换功能,为了安装的方便,减小了主泵的长度,缩短了7-11mm,泵的最大排量增加了6m1/r,保证了性能的稳定性。为了使行走马达的回转体积减小,将液压马达、液压阀和减速机设置成一体,提高减速机的材料强度以用来增强液压马达的承受力。为了能使回转马达安装在驾驶室底下,改变了零部件的装配,降低高度为20%。
通过对改进后的液压系统进行AMESIM仿真,可得到行走马达的输出轴转速更稳定、进出口压力曲线在出现瞬时峰值后,保持稳定,即可保证了挖掘机行走的直线性；通过仿真看到传统回转系统的缺点与不二越回转系统的优点,表明后者的效率提高了、马达进出口压力稳定了。在对整个液压系统的仿真,研究表明,液压系统的功率曲线与发动机的功率曲线基本吻合,在最大程度上满足了全功率控制的目的。从而验证了利用AMESIM软件创建系统的正确性、合理性与参数设置的正确性。
As its unique compact, flexible, multi-function, high efficiency and low price, easy maintenance, mall entire rotation crawler excavator is becoming more and more small earthwork construction units'favorite. Hydraulic system works as an important part of hydraulic excavator, How to make full use of engine power, reduce energy loss of hydraulic excavator is an important issue to be resolved, so doing research of simulation of the hydraulic system, not only can predict the performance of the machine, shorten product design cycle, but can also evaluate the performance of the entire system.
In this paper, I use AMESIM hydraulic simulation software to simulate the system. By analyzing the condition of their working performance, we can optimize the hydraulic system's configuration, improve the overall perfonnance and achieve maximum energy efficiency.
This paper analyzes the structure and components of the hydraulic system and basic principle of circuits, calculating and designing the excavator's hydraulic system. Under the overall performance requirements, on basis of the original depth analysis of the hydraulic system, the following proposed and the innovative technical improvements are as follows:(1) In order to reduce the hydraulic shock, I the increased security without impact valves in designing the motor running, and analyzed the characteristics of the improved hydraulic components; (2) the machine applies full power control system, analyzes Fujio full power control features and characteristics of hydraulic system analysis, calculates and verifies the power matching of the excavator's hydraulic pump in order to meet the full power control purposes; (3) calculated working devices'parameters of the cycle time, blocking force, etc. in various conditions; checking the cylinders'strength and stability:(4) According to the completed schematic diagram of hydraulic system, established mini excavator's cylinder valve, load sensing pump, rotary system, travel system as well as simulation model of the machine hydraulic system.
Before designing the system, I optimized the overall system according to the technical requirements of the overall system. In order to achieve full power control purposes and realize the action switches in a variety of conditions. I increased the switching function in main pump; for the purpose of easy installation. I reduced the length of the main pump and made it 7～11mm shorter, increased by 6ml/r in pump maximum discharge, to guarantee performance's the stability. In order to reduce the size of the rotary motor running, I set the hydraulic motors, hydraulic valves and gear as integration, improved the material strength of gear so as to enhance the affordability of the hydraulic motor. For the purpose of putting the rotary motor mounted under the cab, I changed the assembly of parts, reducing the height to 20%.
Through the improved hydraulic system AMESIM simulation, available walking speed of the motor output shaft is more stable, import and export in the event of transient pressure curve after the peak, remained stable, you can ensure the linearity of excavator; the simulation to see The shortcomings of the traditional rotation system and the advantages of rotary system Fujio, that improves the efficiency of the latter, import and export of motor pressure stable. In the hydraulic system, research shows that the hydraulic system of the engine power curve and power curve are consistent, to the maximum extent to meet the full power control. To verify the system using software to create AMESIM correctness, rationality and parameter settings are correct.
引文
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2.陈德沛.关于液压挖掘机发展的一些状况[J].建设机械技术与管理,1992,(1)：33-35.
3.李永旭,黄宗益.挖掘机液压系统的发展与新技术[J].制冷空调与电力机械,2004,(25)：7-9.
4.孔德文,赵克利,徐宁生等.液压挖掘机[M].北京：化学工业出版社,2009,65.
5.付永领,祈晓野.AMESim系统建模和仿真[M].北京：北京航空航天大学出版社,2006,6-15.
6. Chengen Wang, Lida Xu, Wangliang Peng. Conceptual design of remote monitoring and fault diagnosis systems [J]. Information Systems,2007,32:996-1004.
7.陈志强.试论企业管理创新[J].黄河水利职业技术学院学报,2000,(1)：66-68.
8.刘建民.液压挖掘机关键技术综述[J].建设机械技术与管理,2001,(12)：26-28.
9. Gilbert-Rainer Gillicha, Doina Frunzaverde, Nicoleta Gillich, Daniel Amariei. The use of virtual instruments in engineering education [J]. Procedia Social and Behavioral,2010,2: 3806-3810.
10.刘世亮.挖掘机液压系统节能控制的分析研究[D].甘肃兰州：兰州理工大学,2009.
11.米伯林,奚泉.国外液压挖掘机与液电自动控制[J].现代化农业,1998,(4)：29-30.
12.秦家升.挖掘机液压系统研究[D].吉林长春：吉林大学,2005.
13.黄宏甲,黄谊,王积伟.液压与气压传动[M].北京：机械工业出版社,2000,35-42.
14.陈海军.4WS汽车虚拟模型建模与操纵稳定性仿真[D].江苏南京：南京林业大学,2007.
15.李志刚.1200mm2剪切-闪光对焊机控制系统设计与控制算法的研究[D].天津：河北工业大学,2007.
16.霍夫曼著,陈鹰译.液压元件及系统的动态仿真[M].浙江：浙江大学出版社,1988,115-123.
17.钟廷修.液压CAD技术[J].液压与气压传动.1987,(3)：56-60.
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