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1、<p>  Proportional valve control system of train car system test rig design and research</p><p>  Trains are proportional valve can make the vehicle's braking rate not along with the change of load

2、change, keep a constant, to reduce the train braking on the longitudinal impulse, avoid empty with the braking force is too large to wheels, brake shoe, holding in death of the wheels sliding on the rail abrasion wheel,

3、and heavy car due to insufficient braking force can't park within the prescribed braking distance. Because trains are proportional valve importance related to the personal safety, </p><p>  Railway is th

4、e artery of national economy, it shoulders the heavy task of passenger and cargo transportation. With the rapid development of economic and social progress, the railway passenger traffic volume continues to grow, the tra

5、nsport capacity of railway system is higher and higher requirements are put forward. In this case, in addition to need to put more rail lines, increase the speed of train is a more effective way to solve the capacity sho

6、rtage. On August 1, 2008, the beijing-tianjin i</p><p>  System's hardware design including pneumatic, electric control system, hardware test-bed control system optimization, etc. First of all, based on

7、the sense of train load proportional valve performance test requirements, puts forward the initial scheme of circuit design, clear the design idea and method; Then, through the analysis of the ratio of the initial plan f

8、or the further optimization to improve; Finally, equipped with a pressure transducer, data acquisition card, etc. Main control parts o</p><p>  According to train main test indicators, load proportional valv

9、e test rig must be able to provide for train sense of proportional valve, therefore, in this paper, on the basis of initial design, through the further optimization and improvement of the performance to price ratio, the

10、formation of the final construction scheme optimum pneumatic circuit.</p><p>  Sense of train load is proportional valve need fast charging, exhaust, solenoid valve work frequency is higher, so generally use

11、 the MAC valve company production balance type multi-purpose valve control valve (EP), EP valve pneumatic circuit. Within the dotted line 2 2 2 2 EP solenoid valve and valve (6) constitute a wind, relief valve, controlle

12、d by the master control system of computer, also can through the control panel buttons (1) backup systems, pneumatic systems). Manual control charging b</p><p>  Three channel control mode (computer control

13、of automatic test systems, panel button manually test system, switch valve manually test system), and better satisfy the requirement of the test bench work. Master control system working principle is: the solenoid valve

14、to electricity, EP valve according to the braking instruction, train are proportional valve inflatable and exhaust. Through physical partition loss of electricity, the solenoid, prevent gas pipeline leak, achieve train s

15、ense of proport</p><p>  Because Labview test software set frequency is higher, this circuit structure generally use the MAC valve company produces the balance type multi-purpose valve valve (EP) for measure

16、ment and control. Model: 120B-501BAAD、140B-501BAAD, up to 50 Hz frequency, high sensitivity. EP valve only wiring for power supply and input signal, it can not only make the proportion of pressure, flow direction and flo

17、w control system constitutes a simple, but also facilitate a variety of awaiting approval. EP valv</p><p>  Solenoid valve is used to control fluid flow in the direction of the automation of basic components

18、, belonging to the actuator; Is typically used for machinery and industrial control valve, to control the direction of medium, so as to achieve control of the valve switch. Electromagnet as the driver of the pilot valve,

19、 the performance of the entire element characteristics have important influence, both the steady-state accuracy and dynamic response performance, reliability and anti-interference a</p><p>  Electromagnetic

20、valve selection should first of all, in turn, follow the safety, reliability, applicability and economy of the four principles, the second is based on the six aspects of site conditions (pipeline parameters and fluid par

21、ameters and pressure parameter, electrical parameter, action mode, special requirements to choose) 23 ~ 25.</p><p>  In the pneumatic circuit, using the four common electromagnetic valve, respectively contro

22、l Cv2 mouth signal (Ps) and exhaust wind wind, Cv1 mouth always wind (Pin) charging and exhaust.</p><p>  Because of the Labview test software set frequency is higher, generally use the MAC valve the balance

23、 type multi-purpose valve for measurement and control valve (EP). Model: 120 b - 501 baad baad, 140 b - 140. Up to 50Hz frequency, sensitivity high, the price is relatively high.</p><p>  Ordinary electromag

24、netic valve price at 60 yuan/pairs, but ordinary cannot achieve EP solenoid valve high frequency movement, must carries on the corresponding modification. Measured by test computer send control commands to the solenoid v

25、alve work to 12 ms, drive time is too long, need to drive to 9 ~ 10 ms, drive for 11 hz frequency. Therefore, from the following two aspects in the design of drive time:</p><p>  To improve the original MOS

26、tube + relay mode MOS tube drive systems;Solenoid valve.</p><p>  In order to achieve the rapid absorption of dc electromagnet, release, there are two types of driving mode:</p><p>  Hard drive

27、(constant power driver) :</p><p>  Change the itinerary drives</p><p>  And every other disk</p><p>  Soft drive (power) :</p><p>  High pulse, high suction, the low le

28、vel to maintain after absorption, high level. Japan's Toyota rapier loom USES a high drive, low maintenance. Soft drive implementation requires extra equipment and cost, from the economic point of view, this design U

29、SES the hard drive mode transformation of electromagnetic valve hardware parts:</p><p>  (1) the valve port, from 2 mm to 1 mm, slow airflow;</p><p>  (2) reduce the drive frequency of the low p

30、ressure differential;</p><p>  (3) appropriate to reduce electromagnetic valve travel 0.2 mm;</p><p>  (4) solenoid valve armature in every disk, in order to reduce the electromagnetic valve is

31、reset when the residual magnetism.</p><p>  Through alteration and electromagnetic valve control system, using EP valve solenoid valve replaced, and the precision of the modified can improve to plus or minus

32、 2 kpa, but appeared the overcharge phenomenon, therefore, can be in in solenoid valve import and export, and 0.75 mm orifice, heat causes air currents to flat.</p><p>  Using four two two-way solenoid valve

33、 and a two of the 3-way magnet valve (instead of charging, relief valve, the control principle is as follows:</p><p>  1, 2, DT DT control train sense of proportional valve pressure signal of wind, 3, 4, 5 D

34、T, DT, DT control train load proportion valve outlet pressure;</p><p>  When 1 DT, DT 2 losing electricity, the realization of train load proportional valve signal wind aeration;</p><p>  In ord

35、er to prevent the air flow is too big, appear signal wind overcharge phenomenon, in 1 DT back-end constant orifice plug placement, to slow the flow, to improve control accuracy;</p><p>  Signal charge occurr

36、ed after the wind, through 2 DT exhaust, reduce signal atmosphere pressure;</p><p>  3 DT control output pouring, 4 DT for the exhaust air outlet;</p><p>  5 DT can realize signal in accordance

37、with the requirements of the different wind air, but air flow instability, low control precision;</p><p>  On the basis of the original, to further optimize the gas path, place the 5 DT after 1 DT constant o

38、rifice plug, can achieve different requirements of charging, can also use the same constant orifice plug slow airflow, reduce the air pressure fluctuation, improve control accuracy. This test bench has been formed the fi

39、nal design scheme of pneumatic circuit.</p><p>  列车制车系统比例阀测控试验台的设计与研究</p><p>  火车是比例阀可以使汽车的制动率不随负载变化的变化,保持a恒定不变,减少列车制动纵向冲动,避免空的刹车力太大车轮、制动蹄、抱死车轮轨道平移砂轮和重型汽车由于制动力不足不能把车停在规定的制动距离。因为火车是比例阀的重要性关系到个人安全

40、,质量提出了更高的要求,因此对列车荷载比例阀测试也提出了更多的要求。根据属性的意义上的列车荷载比例阀,比例阀测试试验台的设计研究。最后,在实际的测试表明,该试验测试精度高,性能稳定,加载和卸载测试部分,快速、准确地测定时间短、测试结果、高程度的可视化、历史数据查询方便,可以发展为培训意义上的比例阀和提供可靠的试验依据和在线检测方法。</p><p>  铁路是国民经济的大动脉,它肩负着沉重的任务的客货运输。随着中

41、国经济的高速发展,和社会的进步,铁路客运量不断增长,运输能力的铁路系统是更高和更高的要求提出的。在这种情况下,除了需要把更多的铁路,增加速度的列车是一个更有效的方法来解决产能不足。2008年8月1日,京津城际铁路通车运行正式,标志着时代的到来高速列车在中国,越来越多的高速铁路将于未来。</p><p>  系统的硬件设计包括气动、电气控制系统、硬件试验台控制系统优化等。首先,根据意义上的列车荷载比例阀性能测试需求

42、,提出了初始方案的电路设计,明确设计思想和方法,然后,通过分析比最初的计划进一步优化改善;最后,装有一个压力传感器、数据采集卡等。主要控制部件的电气控制系统,最后完成了列车荷载比例阀控制系统的硬件设计。</p><p>  根据列车的主要测试指标、负载比例阀试验台必须能够提供列车的感觉,因此,比例阀在本文的基础上,初步设计,通过进一步优化和改进的性能价格比,形成最终的施工方案优化气动回路。</p>

43、<p>  意义上的列车荷载比例阀需要快速充电,排气,电磁阀工作频率比较高,所以一般使用MAC阀公司生产平衡式多功能阀控制阀(EP),EP阀气动回路。在虚线2 2 2 2 EP电磁阀和阀(6)构成一个风、安全阀、控制的主控系统的计算机,也可以通过控制面板按钮(1)备份系统,气动系统)。手动控制充电球阀,排气阀构成备用系统2(手动)。被测阀门火车是比例阀充电和排气,用一个压力传感器信号压力和输出电信号,传送到电脑到压力值,同时终

44、端压力表显示空气压力值直接,便于观察。供气压力计显示气源压力,压力计调节负载控制计数器的压力和信号控制计数器的压力。精密调压阀外的组合在进口阀门,减少组合阀进口压力波动、稳定进入气室压力,大大提高精度的稳定性。精密调压阀压力调节压力增加,压差越大,信号的更快和更稳定的风压力上升。但精度的压力调节阀调节压力太高,不利于信号压力下降,经过多次试验,精密调压阀的压力将被派往700 kpa,使高压差较高,信号风压力的稳定和快速上升,同时为了便于

45、信号压力较低的压力降。气体负载体积1 l容量可以减缓压力和输出波动。</p><p>  三个通道控制模式(计算机控制的自动测试系统,面板按钮手动测试系统,开关阀手动测试系统),更好地满足需求的试验台工作。主控制系统的工作原理是:电磁阀电,EP阀根据制动指令,火车是比例阀充气和排气。通过物理分区失去电力,螺线管,防止气体管道泄漏,实现列车意义上的比例阀压力维持。</p><p>  因为虚

46、拟仪器测试软件设置频率较高,这种电路结构通常使用MAC阀公司生产的平衡式多功能阀阀(EP)的测量和控制。模型:120 b - 501 baad,140 b - 501 baad,50赫兹频率、灵敏度高。EP阀只有连接电源和输入信号,它不仅可以使一部分压力,流向和流量控制系统构成简单,但也便于各种等待批准。EP阀的优点是精度高、灵敏度高、可靠性高,可实现精确控制压力管道。然而,如果控制模式、负载(气杆、气体阻力、空气体积)不匹配,控制精度

47、不够,EP阀泄漏问题本身同时,精度是在正负10 kpa的波动和22号要求正负2 kpa试验台。在实验中,信号压力上升得更快,但到达信号压力设定,由于EP阀电荷太快,理解列车荷载比例阀超载一个排水现象严重,如图3.3。信号压力波动较大,不能满足稳定性要求。同时由于工作频率高、频繁开关,容易损坏,而且价格偏高,一个EP阀价格在6000元以上。</p><p>  电磁阀是用来控制流体的方向的自动化基础元件,属于执行机

48、构;通常用于机械和工业控制阀门,以控制介质的方向,从而达到控制阀门的开关。电磁铁作为司机的导阀,整个元素的性能特点有重要的影响,无论是稳态精度和动态响应性能、可靠性和抗干扰能力或工作都在很大程度上取决于电磁体。提高电磁铁吸力特性的综合表现,没有扩大规模,导阀外观改善阀换向性能,电磁铁在推力克服过程中的换向阀芯运动的各种阻力,减少消耗功率的电磁铁,节能、小型化等,是提升目标的电磁阀的性能。</p><p>  电磁

49、阀的选择应该首先,反过来,遵循安全性、可靠性、适用性和经济的四个原则,第二个是基于六方面的立地条件(管道参数和流体参数、压力参数、电气参数、动作方式、特殊要求选择)23 ~ 25。</p><p>  在气动回路,使用四个常见的电磁阀,分别控制Cv2口信号(Ps)和排风风,Cv1嘴巴总是风(销)充电和排气。</p><p>  由于虚拟仪器测试软件设置频率较高,一般使用MAC阀的平衡式多功

50、能阀为测量和控制阀门(EP)。模型:120 b - 501 baad baad,140 b - 140。50赫兹频率,灵敏度高,价格相对较高。</p><p>  普通的电磁阀的价格在60元/双,但一般不能实现EP电磁阀高频运动,必须进行相应的修改。以测试计算机发送控制命令到电磁阀工作到12 ms,开车时间太长,需要开车9 ~ 10毫秒,开车11赫兹频率。因此,从以下两个方面的设计驱动时间:</p>

51、<p>  改进原来的MOS管+中继模式MOS管驱动系统;电磁阀。</p><p>  为了实现快速吸收直流电磁铁,释放,有两种类型的驱动方式:</p><p>  硬盘(恒功率驱动程序):</p><p><b>  改变行程驱动器</b></p><p><b>  和所有其他磁盘</b&

52、gt;</p><p><b>  软驱动(功率):</b></p><p>  高脉冲、高吸水,低水平维持在吸收、高水平。日本的丰田剑杆织机使用高驱动、低维护。软驱动的实现需要额外的设备和成本,从经济的角度来看,本设计采用硬盘模式转换的电磁阀硬件部分:</p><p>  (1)阀口,从2毫米到1毫米,缓慢的气流;</p>&l

53、t;p>  (2)减少驱动频率的低压差;</p><p>  (3)适当减少电磁阀旅行0.2毫米;</p><p>  (4)电磁阀衔铁在每个磁盘,以减少电磁阀复位当剩磁。</p><p>  通过改造和电磁阀控制系统,利用EP阀电磁阀更换,和精密的改性可以提高到正负2 kpa,但出现过充现象,因此,可以在电磁阀进出口,0.75毫米孔板、热使得气流平。<

54、/p><p>  使用四两个双向电磁阀和一个三通电磁阀的两个(而不是充电,安全阀,控制原理如下:</p><p>  1、2、DT DT控制火车的感觉风的比例阀压力信号,3DT、4DT、5 DT,控制列车荷载比例阀出口压力;</p><p>  当1 DT,2DT 失去电力,实现列车荷载比例阀信号风曝气;</p><p>  为了防止空气流量太大

55、,出现超载现象,在信号风1 DT端常数孔塞位置,缓慢的流动,提高控制精度;</p><p>  信号电荷发生风后,通过2 DT排气,减少信号的大气压力;</p><p>  3 DT控制输出浇注、4 DT的排气空气出口;</p><p>  5 DT可以实现信号按照要求不同的风空气,但空气流量不稳定、控制精度低;</p><p>  原来的基

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