节点文献
气动高速开关阀关键技术研究
Research on the Key Technologies of Pneumatic High-Speed on/Off Vavle
【作者】 向忠;
【导师】 陶国良;
【作者基本信息】 浙江大学 , 机械电子工程, 2010, 博士
【摘要】 气动高速开关阀因其体积小、成本低、结构简单、抗污染能力强、功率质量比大、切换迅速等优点,在微电子、医药产品粘结、包装装配及农产品色选系统等工业领域中获得了广泛的应用,并成为当今气动技术研究和发展的重要方向之一。同时,伴随数字集成电路技术的发展,气动高速开关阀在工业自动化中正逐步取代价格高昂的气动比例伺服阀,应用领域由传统的简单开环控制系统向伺服控制系统中拓展,用于实现低成本的力、位移、速度伺服控制。掌握高速开关阀所涉及的系列关键技术,研发具有自主知识产权的气动高速开关阀将有助于更好地满足日益提高的市场需求,进而推动我国在气动元件领域研究的发展,为气动自动化和气动伺服控制技术的发展更好地服务。本文以气动高速开关阀关键技术为研究对象,采用理论分析、解析计算、数值仿真和试验研究相结合的方法,对开关阀所涉及的关键技术进行了系统、深入的研究。通过磁路分析和磁场有限元仿真,分别阐述了电磁铁结构及外部控制参数的作用机理。通过采用缩小衔铁质量的策略,在传统E型电磁铁基础上,提出了ε型电磁铁新结构。仿真与试验结果表明,ε型电磁铁在高速开关阀典型气隙长度范围内电磁力输出能力基本不变(40-60N),而在各种工况下电磁铁的开启速度均有超过10%的性能提升。采用其设计的开关阀开关延时时间分别为0.8ms和0.8ms,气源压力为表压5Bar时流量最高可达70L/min。在此基础上,为进一步缩小电磁铁结构尺寸以满足工业自动化应用中对开关阀结构紧凑性的要求,设计了输出能力在20-30N,结构尺寸为24mm*12mm*3mm的C型紧凑型电磁铁结构。试验结果表明采用其设计的开关阀开关延时时间分别为0.8ms和0.8ms,气源压力为表压4Bar时流量在45L/min左右。最后将所设计开发高速开关阀成功应用于简易光学色选系统,对开关阀的分选能力进行了试验验证。现将各章内容分述如下:第一章主要探讨了电液、气动高速开关阀用电磁铁关键技术的研究进展,分析总结了气动高速开关阀在结构特征、工作状态及应用需求方面所独有的特点及其发展趋势;介绍了开关阀驱动方案、开关阀伺服控制技术和光学色选设备、磁性材料等相关技术进展;第二章从高速开关阀静态流量特性、动态响应特性、及其温度特性与稳定性、寿命特性等几个方面出发,系统论述了气动高速开关阀的静态性能、动态性能及其影响因素,提出了相应设计要点。阐述了磁性材料特性对开关电磁性能的影响,为电磁铁材料选型提供了理论依据。最后,分别以E型、C型电磁铁为电机械转换机构,设计了两种不同结构的气动高速开关阀;第三章在考虑电磁铁边缘磁通和泄露磁通,以及磁性材料饱和特性的基础上,建立了电磁铁的磁路分析模型,得出了有关电磁铁静态力位移关系表达式,初步确定了两种电磁铁的结构参数。建立了电磁铁有限元数值分析模型,对比分析了有限元分析与磁路分析之间的结果;通过二维有限元仿真详细阐述了各结构参数对E型电磁铁静动态特性的影响,通过结构优化得到了新型ε型电磁铁结构,对比分析了电磁铁优化前后的静、动态特性;通过三维有限元仿真分析了各结构参数对C型电磁铁性能的影响,得到了紧凑C型电磁铁结构及其参数。第四章针对有限元方法进行多场耦合求解资源消耗大,计算时间长的问题,分别建立了基于磁通变化和基于有限元-集总参数分析的开关阀动态性能求解模型,以提高开关阀动态特性求解效率。对比研究了不同计算方法下的开关阀动态性能仿真结果,在综合考虑求解速度与计算精度条件下,以有限元求解方法分析了各参数对E型电磁铁开关阀动态性能的影响,而以基于有限元-集总参数的混合模型分析了各参数对C型电磁铁开关阀动态性能的影响,揭示了开关阀动态性能变化规律。最后论述了通过检测阀控腔动态压力变化对开关阀动态性能进行检测的可行性,提出了新型阀控腔动态压力特性测试系统。第五章介绍了开关阀电磁铁力特性测试系统、电磁铁动态位移特性测试系统、基于检测阀控腔动态压力特性获取开关阀响应时间及寿命特性的测试系统、励磁线圈电流特性测试及开关阀流量与温升特性测试系统。基于搭建的测试系统,分别对所开发的两种电磁铁结构开关阀的静动态特性进行了试验分析,并将其与仿真结果作了对比;最后,将设计开发的高速开关阀应用于所设计的简易光电色选系统中,实现了白、黄两色粒子的自动分选功能;第六章概括了全文的主要研究工作和成果,并展望了今后需进一步研究的工作和方向。
【Abstract】 With advantages of low cost, anti-pollution ability, high flow rate gain, small size and simple structure, electro-pneumatic high-speed on/off valves have attracted considerable attention in several areas of modern industry. They have been used in sorting parts, flapping control systems and other systems for gluing, dosing and packaging where discrete cyclic, linear or rotating motions and a very long lifetime are required, and have come to a hot topic of research on the pneumatic technology. Besides, with the development of integrated circuits, they have been used to substite the expensive pneumatic proportional or sevro valve for precise and fine position, force or positon control by adopting pulse witdth modulation technology. Research on the key technology of electro-pneumatic high-speed on/off valve would help to better meet the ever-increasing needs of market and to promote development in the field of pneumatic components of China.Based on theory analysis, mathematical modeling, numerical simulation and experimental study, the pneumatic high speed on/off valves are systematically, deeply researched in the thesis. With magnetic circuit analysis and finite element simulation, the influences of the structural and control parameters on the vavle performance are analyzed in detail. A new s-type solenoid is presented for improving the dynamic characteristics of high speed on/off valve based on traditional E-type solenoid. Simulation and test results indicate thatε-type solenoid considerably reduces the armature weight that the actuator’s response times are decreased by typically 10% under different work conditions with the same level magnetic force. The on/off valve based on this solenoid has a typical on/off time of 0.8ms and 0.8ms, and a maximum volume flow rate of 70L/min under source pressure of 5Bar. A C-type solenoid with a tiny size of 24mm*12mm*3mm is present to meet the compact requiremens from industry automation. It has a typical magnetic force of 20~30N, and the on/off valve based on it has a typical on/off time of 0.8ms and 0.8ms, and a volume flow rate of 45L/min under source pressure of 5Bar. As an application example of the high speed on/off valve, a simplified optical sorting device is successfully developed for sorting particles with different color automatically. The main content of each chapter is summarized as following:In chapter 1, the research progress of high speed solenoids for electro-hydraulic or electro-pneumatic on/off vavles are introduced, and the structural features, working status, application requirements and development trend of pneumatic on/off valves are summarized. Relative technologies such as the valve driving circuits, the pneumatic servo control by using on/off valves, the optical sorting system and the magnetic material are also presented.In chapter 2, from standpoints of the static mass flow rate, the dynamic response characteristics, the temperature performance, and the stability and life performance for pneumatic high speed on/off valves, the design method and acquirements for the valve are summarized. The influences of the magnetic material on the valve static and dynamic characteristics are illustrated in detailly as the design basis, and two on/off valves based on the traditional E-type and C-type solenoids are presented finally.In chapter 3, the magneti circuit models of two high speed solenoids for electro-pneumatic valves are established, fringe flux, leakage flux, and magnetic saturation are took into account in the model. Formulas for deciding the solenoid force are derived and presented explicitly, and then the primitive structrual parameters for two solenoids are presented as the design basis. Finite element models (FEM) of the solenoids are also established, comparisons between the simulation results from the FEM and magnetic circuit model are presented. The action mechanism of the structural parameters on solenoids are analyzed in detail with FEM, and then the specific solenoid structural parameters are determined. A newε-type solenoid is developed based on the traditional E-type solenoid, and a compacted C-type solenoid is also presented to meet the requirement from industrial application.In chapter 4, two numerical analysis models for the dynamic characteristics of on/off valves are presented, one is based on the flux variation in the magnetic ciruit, while the other one is based on hybrid FEM-LPM (Lumped Parameter Model) mode. Comparisons between different simulation methods are presented firstly, and then from standpoints of the simulation efficiency and accuracy, FEM is adopted for the dynamic performance of the E-type solenoid, while the hybrid FEM-LPM method is adopted for the C-type solenoid. Influences of different factors on the on/off valve dynamic properties are simulated, some conlusions are presented for the improvment of dynamic performance of on/off valves.In chapter 5, a series of test rigs for electro-pneumatic high speed on/off valves, such as force-stroke characteristics, armature dynamic stroke, step pressure reponse of the valve command chamber, coil current, valve mass flow rate and the solenoid temperature, are introduced. Based on these systems, the static and dynamic characteristics of two solenoids are measured, and compared with the simulation results. A simplified optical sorting system are developed based on the newly designed valves, particles with different color, such as yellow and white, can be sorted automatically with this system.In chapter 6, all achievements of the dissertation are summarized and the further research work is put forward.