外文翻譯汽車變速器動(dòng)態(tài)建模輪齒局部缺陷的早期檢測

1、 河 北 農(nóng) 業(yè) 大 學(xué)畢業(yè)論文外文資料翻譯學(xué) 院：現(xiàn)代科技學(xué)院 專 業(yè)：農(nóng)業(yè)機(jī)械化及其自動(dòng)化0701班 姓 名：劉旭 學(xué) 號(hào)：2007614290123 外文出處: power and propulsion 附 件：1.外文原文；2.外文資料翻譯譯文完成日期：2011年5月9日 dynamic modeling of vehicle gearbox fox early detection of localized tooth defectnagwa ablhalim,nabil hammed,magdy abdel-hady,shawki abouel-seoud and eid s.moh

2、amed helwan universityabstract dynamic modeling of the gear vibration is a useful tool to study the vibration response of a geared system under various gear parameters and operation conditions. an improved understanding of vibration signal is required for early detection of incipient gear failure to

3、 achieve high reliability. however, the aim of this work is to make use of a 6-degree-of-freedom gear dynamic model including localized tooth defect for early detection of gear failure. the model consists of a gear pair, two shafts, two inertias representing load and prime mover and bearings. the mo

4、del incorporates the effects of time-varying mesh stiffness and damping, backlash, excitation due to gear errors and modifications. the results indicate that the simulated signal shows that as the defect size increases the amplitude of the acceleration signal shows that as the defect size increases

5、the amplitude of the acceleration signal increases. the crest factor and kurtosis values of the simulated signal increase as the fault increases. though the crest factor and kurtosis values give similar trends, kurtosis is a better indicator as compared to crest factor.keywords: vibration accelerati

6、on, system modeling, crest factor, kurtosis value, defect size, gear meshing, pinion, gearnomenclaturejd,j1,j2,jl drive motor, pinion, gear, and load mass moment of inertia replacement decision in a suitable time.m1,m2 masses of pinion and gear.td driving motor torque.tl load torque.tf1,tf2 friction

7、 torque.c1,c2 viscous damping coefficient of pinion and gear bearing.cm gear mesh damping.km gear mesh stiffness.k1,k2 pinion and gear shaft stiffness.4 the variance square.n the number of samples.f the defect width in face direction.kk unit width hertzian stiffness.d, 1,2,l angular displacement of

8、driver motor, pinion, gear and load.d, 1,2,l angular velocity of drive motor, pinion, gear and load.d, 1,2,l angular acceleration of drive motor, pinion, gear and load.introduction much of the past research in the dynamic modeling area has concluded that an essential solution to the problem is to us

9、e a comprehensive computer modeling and simulation tool to aid the transmission design and experiments. these have been two major obstacles to such an approach:（1）progress in understanding of the basic gear rattle phenomenon has been limited and slow. this is because the engine-clutch-transmission s

10、ystem involves some strong momlinearities including gear backlash, multi-valued springs, dry friction, hysteresis, and the like.（2）the gear rattle is a system problem and not only problem of gear teeth. even through the research and industrial community has discussed the difficulties in varies stage

11、s of the problem, yet no thorough frame work covering the entire investigation process of such problem currently exists. this is largely due to the complexity of the power train system, which may make a computer analysis tool inefficient, in particularly when many different elements and clearances a

12、re encountered (e.g.,gears,bearings,splines,synchronizers,and clutch)1-3. a comprehensive review of mathematical models used in gear dynamics, published before 1986,has been presented by4.in this review, gear dynamic models without defects have been discussed. in the past few years, researchers have

13、 been working on the gear dynamic models which include defects like pitting, spalling, crack and broken tooth. a single-degree-of-freedom model is used which include the effects of variable mesh stiffness, damping, gear errors, profile modifications and backlash. the effect of time-varying meshing d

14、amping is also included in this case. the solution is obtained by using the harmonic balance methods. a method of calculated the optimum profile modification has been proposed in order to obtain a zero vibration of the gear pair5-7.they also proposed a linear approximate equation to mode the gear pa

15、ir by using a single-degree-of freedom model. gear rattle vibration is a undesirable vibration for passenger cars and light trucks equipped with manual transmissions. unlike automatic transmissions, manual transmission do not have the high viscous damping inherent to a hydrodynamic torque converter

16、to suppress the impacting of gear teeth oscillating through their gear backlash. therefore a significant level of vibration an be produced by the gear rattle and transmitted both inside the passenger compartment and outside the vehicle.gear rattle, idle shake, and other vibration generated in the au

17、tomobile driveline have become an important concern to automobile manufactures in their pursuit of an increased level of perception of high vibration quality. the torsional vibration driveline is a major source of gear rattle vibration. the manual transmission produces gear tattle by the impacting o

18、f gear oscillating though their gear backlash. the impact collisions are transmitted to the transmission housing via shafts and bearings8.the gear pair dynamic models including defects have been done by 9. the study suggests that little work has been done on modeling of gear vibrations in the presen

19、ce of local tooth fault has yet to be develop a multidegree-of-freedom nonlinear model for a gear pair that can be used to study the effect of lateral-torsional vibration coupling on vibration response in the presence of localized tooth defect. a typical fault signal is assumed to be impulsive in na

20、ture because of the way it is generated. the simulation artificially introduced pitting in gears in multi-stage automotive transmission gearbox at different operation conditions (load, speed. etc).the processing of simulated and experimental signals is also introduced.signal-processing techneque amo

21、ng various signal-processing techniques,crest factor and kurtosis analysis have been used for analyzing the whole vibration signal for the early detection of fault. in this section, crest factor and kurtosis value have been explained.mathematical model formulation helical gears are almost always use

22、d in automotive transmissions. the meshing stiffness of a helical tooth pair is time-varying10, and was modeled as a series of suggested spur gears so that the simulation techniques for spur gears can be applied. where m is module(mm), b is face width(mm),is pressure angle (deg), is helix angle (deg

23、) and d1 is pitch diameter (mm). fig.2 shows the equivalent gear system in the first gear-shift, where the main parameters for the gear system of fiat-131gearbox and the equivalent gear system in the first gear-shift are also shown in the figures.汽車變速器動(dòng)態(tài)建模輪齒局部缺陷的早期檢測nagwa abd-elhalim, nabil hammed,

24、magdy abdel-hady, shawki abouel-seoud and eid s. mohamed阿勒旺大學(xué)摘要在研究齒輪系統(tǒng)中各種齒輪參數(shù)的振動(dòng)響應(yīng)和操作條件時(shí)，齒輪振動(dòng)的動(dòng)態(tài)建模是一個(gè)非常有用的工具。對(duì)早期的齒輪檢測提出了一種改進(jìn)理解的振動(dòng)信號(hào)，但還沒達(dá)到高的可靠性。但是，這項(xiàng)工作的目的是利用一個(gè)6自由度的齒輪動(dòng)力學(xué)模型對(duì)齒輪輪齒缺陷故障的早期檢測。該模型包括一對(duì)齒輪副、兩個(gè)軸、兩個(gè)慣性負(fù)載、動(dòng)力傳動(dòng)裝置和軸承。由于齒輪的誤差和變動(dòng)，該模型被采用時(shí)受到變嚙合剛度、阻尼、反彈和勵(lì)磁影響。模擬信號(hào)顯示的結(jié)果表明，隨著缺陷尺寸的增加加速度信號(hào)的振幅增加。模擬信號(hào)的波峰因素和峰值隨著

25、缺陷的增加而加重。雖然波峰因素和峰值做同樣的趨勢，但和波峰因素相比峰值是一個(gè)比較好的指標(biāo)。關(guān)鍵詞：振動(dòng)加速度、系統(tǒng)建模、波峰因素、峰值、缺陷大小、齒輪嚙合、齒輪專業(yè)術(shù)語jd, j1, j2, jl 驅(qū)動(dòng)電機(jī)、小齒輪、大齒輪和負(fù)載在一定時(shí)間內(nèi)的慣性矩m1, m2 大齒輪、小齒輪的模數(shù)td 發(fā)動(dòng)機(jī)驅(qū)動(dòng)轉(zhuǎn)矩tl 負(fù)載力矩tf1, tf2 摩擦力矩c1，c2 齒輪、軸承的粘滯阻尼系數(shù)cm 齒輪嚙合阻尼km 齒輪嚙合剛度k1, k2 齒輪、齒輪軸的剛度4 平方差n 樣本數(shù)量f 寬度方向的缺陷kk 單位寬度的剛度d, 1,2,l 驅(qū)動(dòng)電機(jī)、小齒輪、大齒輪和負(fù)載的角位移d, 1,2,l 驅(qū)動(dòng)電機(jī)、小齒輪、大

26、齒輪和負(fù)載的角速度d, 1,2,l 驅(qū)動(dòng)電機(jī)、小齒輪、大齒輪和負(fù)載的角加速度引言在大多數(shù)過去的動(dòng)態(tài)建模研究領(lǐng)域中，解決問題的重要辦法是全面使用計(jì)算機(jī)建模和仿真工具來輔助變速器的設(shè)計(jì)和實(shí)驗(yàn)。這種方法有兩種主要的障礙：（1）對(duì)齒輪傳動(dòng)中噪聲基本認(rèn)識(shí)的進(jìn)展是有限的和緩慢的。這是因?yàn)榘l(fā)動(dòng)機(jī)離合器傳動(dòng)系統(tǒng)中包括齒輪側(cè)隙、多值彈簧、非線性滯后等等。（2）齒輪發(fā)出的噪聲是一個(gè)系統(tǒng)問題，并不是齒輪的唯一問題。即使是工業(yè)研究領(lǐng)域已經(jīng)討論了這個(gè)問題在不同階段所出現(xiàn)的不同問題，但并沒有徹底覆蓋工作的框架，整個(gè)研究過程中的問題依然存在。這主要是由于列車電力系統(tǒng)的復(fù)雜性，可能導(dǎo)致你的計(jì)算機(jī)地分析工具效率不高，尤其是工作中遇到許多不同的因素和間隙（例如：齒輪、軸承、花鍵、同步器和離合器）。在1986年出版之前，對(duì)齒輪動(dòng)