译文:
1、引言
汽车动力转向液压泵是动力转向系统的心脏,其性能好坏对汽车动力转向系统的性能有着重要的影响,并将直接影响到汽车的转向和操纵稳定性。此外,随着新材料、新工艺、新结构的不断应用,以及轿车用高速转向液压泵的大量引进,对转向液压泵性能的试验研究更为迫切,因此,必须对转向液压泵试验方法进行深入探讨,提出行之有效的试验方法,完善试验手段,深入研究转向液压泵特性。
动力转向液压泵在试验过程中,需要测量的主要参量除了一般液压泵具有的温度、流量、压力、转速、转矩等特性参量外,由于动力转向液压泵的特殊结构和使用要求决定了它有其特定的性能,因此在研制动力转向液压泵试验台时,如何能准确、方便地测量转向液压泵的性能参量,便是最为关键的问题。
2、动力转向液压泵试验方法
转向液压泵试验标准“ZBT23002汽车动力转向液压泵台架试验方法”是1984年开始制订,1987年颁布执行,现已使用十多年。当时,国内汽车动力转向液压泵产品均为齿轮泵,轿车转向液压泵还是空白。
随着近几年汽车工业的迅速发展,动力转向液压泵行业也有了长足进步,转向叶片泵几乎取代了齿轮泵,轿车转向液压泵得到了广泛使用,特别是大量国外技术的引进,原试验方法已较落后,不能全面、准确地检测现有产品。尤其是1997年1季度,重庆汽车研究所在承担国家技术监督局下达的汽车转向液压泵产品质量抽查任务中发现,原试验方法远远不能满足现有产品的检测要求,而且在试验过程中难以操作,对产品质量的好坏很难做出全面、公正、准确的评价。
因此,为适应我国汽车工业产品的发展需要,有效地控制产品质量,对试验方法进行深入探讨和研究很有必要。 2.1、0.85pmax压力概念
原试验方法要求在做跑合、流量检测等性能试验时,产品是在{zg}工作压力pmax条件下进行的,此时转向液压泵安全阀已xx开启,处于流量为0的断流状态,根本无法试验,并且容易烧泵。试验时为了避免转向液压泵安全阀的开启,在试验前,必须将转向液压泵安全阀锁死。这种做法相当于对液压泵进行了调整,因而该方法既不科学,也不符合装车状况,同时也不能较全面、准确地检测出产品使用性能。因此提出了0.85pmax压力概念,即产品在0.85倍{zg}压力条件下进行跑合和流量检测等性能检测,此时转向液压泵安全阀不会开启,这样检测出的性能才准确地反映了转向液压泵的真实情况。
2.2、气密性试验
原试验方法没有气密性试验要求,通过大量的试验表明,气密性试验能够准确、可靠地反映转向液压泵密封件的密封性和各零件之间的装配质量,并且试验简便、可行,成本低廉,容易推广应用。
2.3、可靠性试验的油温 转向液压泵的使用工况比一般工程用泵的使用工况要复杂得多。
使用时,转向液压泵常处于转速、压力多变的复杂工况下,油温变化剧烈且范围较大。加之在转向液压泵出油口处都安装了孔径很小的节流孔,使多余流量溢流泄出,并直接返回进油腔,在转向液压泵内形成小循环,这使转向液压泵发热现象比一般泵要严重得多。同时,由于受结构的限制,转向液压泵在整车上一般安装于发动机旁,环境温度很高,因而转向液压泵发热更为严重。而且动力转向系统中油液很少,一般为1~3L,其热量不易散发。
因此,为了准确地考核转向液压泵的使用性能和寿命,其试验油温在70℃左右为宜。 2.4、断流试验
原试验方法中参照一般泵的试验方法,提出了断流试验。由于动力转向器总成一般均有行程卸荷阀,当转到极限位置时,行程卸荷阀开启,使转向液压泵处于卸载状态。即使没有行程卸荷阀,由于动力转向器总成内不可避免的会有一定的内泄漏量,因而转向液压泵也不会处于断流状态。特别是叶片泵几乎没有断流能力。因此,应取消断流试验项目。
2.5、变转速冲击试验
众所周知,由于转向的特殊使用工况,汽车在行驶过程中,转向液压泵根本不可能处于连续超载状态。相反,汽车在行驶过程中,其行驶速度在不断的变化,而转向系统又随时在确保汽车按一定的轨迹行驶,由于路面的原因,转向车轮也不断的受到路面的逆向冲击,因而汽车行驶过程中转向液压泵不断的承受到冲击载荷。
为了使试验工况与实际使用工况相一致,使试验数据真实、准确地反映转向液压泵的使用寿命,因此提出了将原试验方法中的连续超载试验改为变转速冲击试验。
3、试验台结构简介
驱动装置采用交流变频调速,交流电机通过连接套及滑块直接驱动被试泵,对于不同安装形式的试件只须更换连接法兰盘与滑块即可。
油箱安装在工作台面上,容积约150L,油箱内安装有3kW加热器,油箱底部距驱动轴中心高约为200mm,吸油口管径为30mm,可以保证被试液压泵吸油良好。油箱面板配有真空表和压力表,以监测吸油口真空度和出油口加载压力。
吸、回油口均采用快换接头,使其安装简便、迅速,同时防止油箱油液流出。 4、试验台液压系统
该试验台采用比例溢流阀加载,由计算机通过电信号控制比例电磁阀进行加载,并且通过压力传感器反馈信号对比例溢流阀进行微调,其加载准确,实现了加载过程自动化。
由于被试件在不停地更换,必将给整个系统带来大量的污染物,而比例溢流阀对油液的清洁度要求较高。因此,为了确保整个系统的正常运行。设计时采用了2级高压过滤。使其过滤精度达到5μm,并且采用全封闭油箱。
油液的黏度受油温的影响极大,为了确保流量测试的准确,系统使用水冷却器对油温进行严格控制,使其变化范围在±2℃之内。 5、试验台测试系统
该试验台的测试参量有转速、流量、压力、温度等4个参量。
转速传感器是电感式传感器,它的输出为正弦波信号,经三极管放大后,由施密特电路(4093芯片)整形,并经电阻分压,输入到反向器(4011)的输入端,再由反向器的输出端接到计算机7210板的G2端。由于4093芯片的可靠触发电平在6V以上,所以加在三极管及4093上的电压均采用12V,这样经4093整形后输出的高电平为12V,低电平为0V,而计算机输入电压以不高于5V为宜,所以经电阻分压,再经反向电路后,将5V电压的脉冲信号送入计算机。
流量传感器的输出本身是12V的脉冲信号,每个脉冲代表0.1L。在计数流量脉冲时,若以定时间计脉冲数,{zd0}可以近似于丢掉1个脉冲数,而且由于测试时间较短,丢掉的脉冲数还将被放大,这样就必然产生较大的测量误差。因此,在计数流量脉冲数时,以定脉冲测时间的方法更为准确。
为了减少干扰,压力、温度的信号均采用4~20mA的模拟量,将信号通过HK16芯插头直接送到5411板进行A/D转换。
试验台的正确接地可以防止外部干扰信号。由于使用??严重的干扰。对该测试系统的接地问题进行了大量探索后,最终圆满地解决了干扰的问题。不管保护方式是接地保护还是接零保护,线路的走向都必须按如下方式:零(地)线首先进入变频器的接地端,然后引向试验台架,再与控制柜连接(注意不要用单芯线),由于变频器是挂在控制柜上,所以在安装变额器时,必须将变频器的外壳与机柜绝缘。
6、试验台计算机系统
控制软件为基于MS-DOS操作系统的先进多任务工业控制组态软件,该软件具有全中文图形提示、操作简便可靠、界面好等优点。经实践证明是一个较为优秀的工业控制组态软件。
6.1、硬件系统 主机为IPC486DX4/100 EPSON300K打印机 6.2、软件系统
工业控制组态软件可图形显示工况,在线打印报表,提供手动及自动操作画面。在手动操作中具有图形提示功能。
本工业控制组态软件由以下文件组成: CHZHI.EXE可执行软件 SYS.DAT组态数据文件 CQHI16J.116点阵字库
CBTYPE.DAT型号数据文件 7、结论
通过大量的试验摸索,提出了切实可行的转向液压泵试验方法。经一年多的生产实际使用证明,该试验方法易于操作,测试结果能真实、准确地反映转向液压泵的使用性能。经使用证明,ZYBT-Ⅱ型汽车转向液压泵试验台工作安全可靠,性能稳定,试验过程全自动化,操作简便,适应性强,测试结果准确可信,并且大大地提高了试验效率,具有广泛推广使用的价值。
“ Dynamic pump test methods and test equipment”是由提供的国际水泵新闻,译文仅供参考。另外,中国磁力泵网还提供相关产品搜索:、、、、等。
原文:
1 Introduction Auto power steering pump power steering system is
the heart of good or bad performance on the performance of
automotive power steering system has an important effect, and will
directly affect the car's steering and handling stability.
Moreover, with new materials, new processes, new structures
continue to apply, as well as cars with the introduction of a large
number of high-speed steering pump, steering pump on the Study on
the performance even more urgent, therefore, must thoroughly test
methods Steering Pump discussed, effective test method, perfect
testing means, in-depth research to pump characteristics. Power
steering pump in the trial process, the need to measure the main
parameters in addition to the general hydraulic pump with the
temperature, flow, pressure, speed, torque and other
characteristics parameters, the power steering pump as the special
structure and determine its use requirements their specific
performance, the power
steering pump in the development test bed, how can accurately and
easily measure the performance parameters of steering hydraulic
pump, is the most crucial issue. 2, power steering pump test
methods Steering Pump Test Standard "ZBT23002 vehicle power
steering hydraulic pump bench test method" is a 1984 development,
implementation was enacted in 1987, has been used more than a
decade. At that time, the domestic automobile power steering pump
products are gear pumps, car steering pump, or blank. With the
rapid development of automobile industry in recent years, power
steering pump industries have made great progress, steering gear
vane pump has almost replaced the pump, car steering pump is widely
used, especially the introduction of a large number of foreign
technology, the original test method has fallen behind, unable to
fully and accurately detect existing products. In particular, a
quarter in 1997, Chongqing Automobile Research Institute Bureau of
Technical Supervision issued in assuming quality steering pump
sampling mission found that the original test method can not
satisfy the testing requirements of existing products, but also in
the testing process is difficult operation, product quality is good
or bad is difficult to make a comprehensive, just and accurate
evaluation. Therefore, to meet the development needs of China's
automobile industry products, effective control of product quality,
depth of test methods and research is necessary. 2.1,0.85 pmax
pressure concept The original test method requires to do
running-in, flow testing and other performance tests, the product
is at the highest working pressure pmax conducted under the
conditions at this time steering pump valve is fully open, at the
traffic stop state 0 is impossible test and burn easily pump.
Steering Pump tests in order to avoid safety valve open, during the
trial before the pump relief valve must be turned to lock. This is
the equivalent of hydraulic pumps were adjusted so that the method
is neither science nor meet the loading conditions, while not
comprehensive, and accurate detection of product performance. Thus
the pressure raised 0.85pmax the concept that the product of 0.85
times the maximum pressure conditions and flow under the running-in
detection performance testing, this time steering pump safety valve
will not open, so that the performance of detection was an
accurate reflection of the hydraulic steering pump the real story.
2.2, air tightness testing The original test method does not leak
test requirements, through a large number of tests show that the
leak test can accurately and reliably reflect the steering pump
seal and sealing assembly between the quality of parts, and test
simple, feasible, cost cheap, easy to expand the applications. 2.3,
oil temperature reliability test Steering hydraulic pump condition
using the pump than the use of engineering is much more complex
conditions. Use, often at speed steering pump, the pressure varied
complex conditions, the oil temperature range of rapid change, and
more. Coupled with the oil in the steering pump installed in the
mouth are very small orifice diameter, so that extra traffic
overflow escape, and returned directly into the oil chamber, to
form small cycles in the steering hydraulic pump, which makes heat
Steering Pump phenomenon is much more serious than the pump. At the
same time, due to structural limitations, steering pump installed
in the motor vehicle generally adjacent to the ambient temperature
is high, and therefore turned to more serious heat pump. And the
power steering system, very little oil, usually 1 ~ 3L, its not
easy to distribute the heat. Therefore, in order to accurately
assessing performance and the use of Steering Pump Life, the test
oil temperature about 70 ℃ suitable. 2.4, the stop-test The
original test method, test methods refer to the general pump
proposed drying test. As the power diverter valve generally have a
trip unloading, when the go to the limit position, the trip
unloading valve is opened, so that steering hydraulic pump in the
unloaded state. Even without the trip unloading valves, power
steering assy because there will be inevitable within a certain
amount of internal leakage, which in turn pump will not stop state.
In particular, leaves almost no drying capacity of the pump. So,
stop the pilot project should be canceled. 2.5, variable speed
impact test As we all know, due to the special use conditions
shift, the car is moving process, the steering pump is impossible
in a state of continuous overload. Instead, the car is moving
process, its speed is changing, and steering system has at any time
to ensure that vehicles traveling at a certain path, because the
reasons for the road, steering wheels are constantly subject to
adverse impact of the road, which vehicle was constantly bear in
the steering pump to the impact load. In order to test the actual
use conditions and conditions consistent with the experimental data
so that the true and accurate reflection of the life of steering
pump, so the original test method proposed in the continuous
overload test to variable speed impact test. 3 Test structure
Introduction Use AC variable frequency drives, AC motor and the
slider by connecting sets of direct-drive pump is tested for
different forms of test pieces to install only necessary to replace
connecting flange and the slide can be. Tank mounted on a
countertop, the volume of about 150L, 3kW heater installed inside
the tank, the tank bottom from the drive shaft center height is
about 200mm, suction port diameter 30mm, can ensure good suction
pump was tested. Tank panel with vacuum table and the pressure
gauge to monitor the inlet vacuum and pressure on the oil export
loading. Suction, return oil port quick couplers are used to make
it easy to install quickly, while preventing the outflow of oil
tank. 4, test hydraulic systems The test bed load proportional
relief valve, controlled by the computer through the electrical
signal proportional to load solenoid valve, and pressure sensor
feedback signal through the proportional relief valve for fine
tuning, the load accurately, to achieve the loading process
automation. Because the sample is constantly being replaced, will
bring the whole system a lot of pollutants, proportional relief
valve on the oil's cleanliness demanding. Therefore, in order to
ensure the normal operation of the system. Designed with two
high-pressure filtration. Its filtering accuracy 5μm, and a fully
enclosed tank. The viscosity of the oil greatly influenced by the
oil temperature to ensure the accuracy of flow measurement, the
system uses the water cooler on the strict control of oil
temperature, it varied within the ± 2 ℃. 5 Test System The test
stand the test parameters are speed, flow, pressure, temperature
and other parameters 4. Inductive speed sensor is a sensor, its
output sine wave signal, amplified by the transistor, the Schmidt
circuit (4093 chip) plastic, and by the resistance divider, input
to the inverter (4011) input, and then The output from the inverter
board of the G2 receiving end computer 7210. As the 4093 chip,
reliable trigger level in more than 6V, it added to the voltage on
the transistor and 4093 are used 12V, so by 4093 the output of high
plastic for the 12V, low to 0V, while the input voltage to the
computer is not higher than the 5V is appropriate, therefore, the
resistor divider, and then by reverse circuit, will 5V voltage
pulse signal into the computer. Flow sensor output itself is 12V pulse signal, each pulse representative of 0.1L.
Pulse flow in the count, the total number of pulses if given time,
the maximum you can lose a similar number of pulses, and because
time is short, losing the pulse number will be enlarged, so that
must have a greater measurement error. Therefore, when counting the
number of flow pulses to be pulsed method is more accurate
measurement of time. To reduce interference, pressure, temperature,
4 ~ 20mA signals were simulated using the amount of the signal by
HK16 core plug directly to the 5411 board for A / D conversion.
Test bed is properly grounded to prevent external interference
signals. The use?? Serious interference. Grounding of the test
system to explore the issue a lot, the final satisfactory solution
to the interference problem. Way regardless of grounding protection
to protect or take zero protection, the trend line must be as
follows: zero (ground) cable first into the inverter's grounding
terminal, and then lead the test bench, and then connect with the
control panel (be careful not to single core), due to frequency
converter is linked to the control cabinet, so when you install
variable device, the inverter must be insulated shell and cabinet.
6, testing computer systems Control software for MS-DOS operating
system based on advanced multi-task configuration of industrial
control software, which has prompted the whole Chinese graphical,
easy and reliable interface and good. Is a more proven excellent
industrial control configuration software. 6.1, the hardware system
Host IPC486DX4/100 EPSON300K Printers 6.2, software system
Industrial control configuration software graphic display
condition, on-line print statements, to provide manual and
automatic operation of the screen. In the manual with graphic
prompts. The industrial control configuration software from the
following files: CHZHI.EXE executable software SYS.DAT
configuration data files CQHI16J.116 dot matrix font CBTYPE.DAT
model data file 7 Conclusion Explored through a large number of
tests, made practical test methods Steering Pump. The actual use of
the production of more than a year to prove that the experimental
method is easy to operate, test results can be truly and accurately
reflect the steering hydraulic pump performance. The use of proven,
ZYBT-Ⅱ type steering hydraulic pump test stand safe and reliable,
stable performance, fully automated test procedure is simple,
adaptable, accurate and reliable test results, and greatly improved
the test efficiency, with widely use value.
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