【作者】 胡洋；

【导师】 王广林；

【作者基本信息】 哈尔滨工业大学 ， 机械制造及其自动化， 2010， 硕士

【摘要】 在电液伺服控制系统中,电液伺服阀将系统的电气部分和液压部分连接起来,实现对液压执行元件的控制,是系统的关键元件。喷嘴和节流孔是伺服阀中的重要零件,其小孔的压差流量特性将直接影响到伺服阀性能,单凭测量尺寸很难达到使用要求,因此大都通过压力和流量的测量方法来满足。在双喷嘴挡板电液伺服阀中的小孔零件都要求其结构对称,因此需要从加工好的喷嘴(节流孔)中挑选出那些压差-流量特性相似的进行两两配对,配好对的小孔零件才可以安装到伺服阀中使用。目前国内伺服阀小孔零件配对还停留在人工配对的阶段,效率低、劳动强度大、误差大,不易最优配对。本文在研究伺服阀小孔零件压差-流量特性的基础上,首先对伺服阀小孔零件的压差-流量配对测量原理和压力配对测量原理进行了阐述,对自动配对测量系统的总体和各组成部分进行了设计与研制,包括测量油路部分、回油泵站部分、压力控制部分和温度控制部分等。然后,结合虚拟仪器技术对测量系统的软件的总体功能和结构模式进行了研究。采用了状态机与事件机的混合编程模式实现了对测量软件的编制。再后,对压差-流量配对测量中采用的配对算法进行了研究,基于不同的配对需要并结合计算机算法原理中的贪心算法思想,提出了最优配对算法和最多配对算法。最后,通过在测量系统上进行了精度实验验证了系统的测量精度,又通过实验分别验证并实现了最优配对算法和最多配对算法,并在测量软件和数据库的基础上完成测试程序。更多还原

【Abstract】 In a electro-hydraulic servo control system, electro-hydraulic servo valve which is the key part of the system connects the electrical part and hydraulic part and implements to hydraulic actuator’s control. Nozzle and orifice are very important parts in servo valve, whose flow characteristic under various pressure differences directly affects the function of servo valve, and it is difficult to guarantee its service performance by measuring the dimension, so a high precise measuring instrument is urgently required. The twin flapper-nozzle electro-hydraulic servo valve has strict symmetric structure, so the pairs of nozzle and orifice are required which has consistent flow characteristics, and the process to select the pairs of nozzle or orifices is called as“pairing”. At present, the domestic factories for servo valve mostly adopted manual measuring method to select the pairs of nozzle and orifices. This traditional method has heavy labor intensity as well as high error rate, so the pairing efficiency is very low, furthermore, it is difficult to obtain optimum pairing results.Based on the deep research of flow characteristics for the small orifice of nozzle, this dissertation firstly gives a description of pressure-flow measurement and pressure measurement of servo valve small orifice part taking a development of the whole measurement system and its several parts, including its hydraulic power, reusing oil system, pressure-control and temperature-control parts.Secondly, combining with virtual instrument technology this dissertation gives a deep research on the structure and mode of the measurement software based on state machine and case machine construction complete the software program.Thirdly, this dissertation gives a research on the pairing algorithms of pressure-flow measurement. According to the basic principle of greedy algorithm and different production occasions this dissertation proposes two kinds of algorithms which are optimal paring algorithm and most paring algorithm.Finally, by means of taking experiments on the measurement system the measurement accuracy and the correctness of the pairing algorithms are verified, then based on the automatic measuring software and database of the measurement system, the pairing program is accomplished.更多还原