2023年全國碩士研究生考試考研英語一試題真題(含答案詳解+作文范文)_第1頁
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1、<p><b>  汽 車 懸 架</b></p><p>  現代汽車中的懸架有兩種,一種是從動懸架,另一種是主動懸架。 </p><p>  從動懸架即傳統(tǒng)式的懸架,是由彈簧、減振器(減振筒)、導向機構等組成,它的功能是減弱路面?zhèn)鹘o車身的沖擊力,衰減由沖擊力而引起的承載系統(tǒng)的振動。其中彈簧主要起減緩沖擊力的作用,減振器的主要作用是衰減振動。由于這種懸架是

2、由外力驅動而起作用的,所以稱為從動懸架。 </p><p>  而主動懸架的控制環(huán)節(jié)中安裝了能夠產生抽動的裝置,采用一種以力抑力的方式來抑制路面對 </p><p>  車身的沖擊力及車身的傾斜力。由于這種懸架能夠自行產生作用力,因此稱為主動懸架。 </p><p>  主動懸架是近十幾年發(fā)展起來的,由電腦控制的一種新型懸架,具備三個條件: </p>

3、<p> ?。?)具有能夠產生作用力的動力源; </p><p>  (2)執(zhí)行元件能夠傳遞這種作用力并能連續(xù)工作; </p><p> ?。?)具有多種傳感器并將有關數據集中到微電腦進行運算并決定控制方式。因此,主動懸架匯集了力學和電子學的技術知識,是一種比較復雜的高技術裝置。 </p><p>  例如裝置了主動懸架的法國雪鐵龍桑蒂雅,該車懸架系統(tǒng)的中

4、樞是一個微電腦,懸架上有5 種 </p><p>  傳感器,分別向微電腦傳送車速、前輪制動壓力、踏動油門踏板的速度、車身垂直方向的振幅及頻率、轉向盤角度及轉向速度等數據。電腦不斷接收這些數據并與預先設定的臨界值進行比較,選擇相應的懸架狀態(tài)。同時,微電腦獨立控制每一只車輪上的執(zhí)行元件,通過控制減振器內油壓的變化產生抽動,從而能在任何時候、任何車輪上產生符合要求的懸架運動。因此,桑蒂雅橋車備有多種駕駛模式選擇,駕車

5、者只要扳動位于副儀表板上的“正?!被颉斑\動”按鈕,轎車就會自動設置在最佳的懸架狀態(tài),以求最好的舒適性能。 </p><p>  另外,主動懸架具有控制車身運動的功能。當汽車制動或拐彎時的慣性引起彈簧變形時,主動懸架會產生一個與慣力相對抗的力,減少車身位置的變化。例如德國奔馳2000 款CL 型跑車,當車輛拐彎時懸架傳感器會立即檢測出車身的傾斜和橫向加速度,電腦根據傳感器的信息,與預先設定的臨界值進行比較計算,立即

6、確定在什么位置上將多大的負載加到懸架上,使車身的傾斜減到最小。 </p><p>  汽車主動懸架—液壓和空氣式</p><p>  從控制力的角度劃分,懸架可分為被動懸架,半主動懸架和主動懸架。目前,大多數汽車的懸架系統(tǒng)裝有彈簧和減振器,懸架系統(tǒng)內無能源供給裝置,其彈性和阻尼不能隨外部工況變化,因此稱這種懸架是被動懸架。</p><p>  主動懸架有作為直接力發(fā)

7、生器的動作器,可以根據輸入與輸出進行最優(yōu)的反饋控制,使懸架有最好的減震特性,以提高汽車的平順性和操縱穩(wěn)定性。它由彈性元件C和一個力發(fā)生器Fe組成。 </p><p>  半主動懸架可看作由可變特性的彈簧和減振器組成的懸架系統(tǒng),雖然它不能隨外界的輸入進行最優(yōu)的控制和調節(jié),但它可按存儲在計算機的各種條件下最優(yōu)彈簧和減振器的優(yōu)化參數指令來調節(jié)彈簧的剛度和減振器的阻尼狀態(tài)。它由彈性元件C 和一個一個阻尼系數能在較大范圍內

8、調節(jié)的阻尼器組成。 </p><p>  電子技術控制汽車懸架系統(tǒng)主要由(車高、轉向角、加速度、路況預測)傳感器、電子控制ECU、懸架控制的執(zhí)行器等組成。系統(tǒng)的控制功能通常有以下三個: </p><p>  1 車高調整 當汽車在起伏不平的路面行駛時,可以使車身抬高,以便于通過;在良好路面高速行駛時,可以降低車身,以減少空氣助力,提高操縱穩(wěn)定性。 </p><

9、;p>  2 阻尼力控制 用來提高汽車的操縱穩(wěn)定性,在急轉彎、急加速和緊急制動情況下,可以抑制車身姿態(tài)的變化。 </p><p>  3 彈簧剛度控制 改變彈簧剛度,使懸架滿足運動或舒適的要求。采用主動式懸架后,汽車對側傾、俯仰、橫擺跳動和車身的控制都能更加迅速、精確,汽車高速行駛和轉彎的穩(wěn)定性提高,車身側傾減少。制動時車身前俯小,啟動和急加速可減少后仰。即使在壞路面,車身的跳動也較少,輪胎對地面的附著

10、力提高。 </p><p>  一.主動式液壓懸架 </p><p>  電子控制的主動式液壓懸架能根據懸架的質量和加速度等,利用液壓部件主動地控制汽車的振動。主動式液壓懸架在轎車上的布置如圖所示,在汽車重心附近安裝有縱向、橫向加速度和橫擺陀螺儀傳感器,用來采集車身振動、車輪跳動、車身高度和傾斜狀態(tài)等信號,這些信號被輸入到控制單元ECU,ECU 根據輸入信號和預先設定的程序發(fā)出控制指令,控

11、制伺服電機并操縱前后四個執(zhí)行油缸工作。 </p><p>  二.主動式空氣懸架 </p><p>  在電子控制的主動式空氣懸架系統(tǒng)中,微機根據傳感器送來的信號和駕駛員給予的控制模式經過運算分析后向懸架發(fā)出指令,懸架可以根據微機給出的指令改變懸架的剛度和阻尼系數,是車身在行駛過程中保持良好的穩(wěn)定性能,并且將車身的振動響應控制在允許的范圍內。一般說來,主動式空氣懸架的控制內容包括車身高度、

12、減振器衰減力、彈簧彈性系數等三項; </p><p>  1車高的控制;分標準、升高和只升高后輪三種工作狀態(tài); </p><p>  2減震器的衰減力控制分低、中、高三檔; </p><p> ?。晨諝鈴椈傻膹椥韵禂捣周?、硬兩檔。 </p><p>  空氣懸架電子控制系統(tǒng)的工作原理;用空氣壓縮機形成壓縮空氣,并將壓縮空氣送給彈簧和減震器的空

13、氣室中,以此來改變車輛的高度。在前輪和后輪的附近設有車高傳感器,按車高傳感器的輸出信號,微機判斷出車輛高度,再控制壓縮機和排氣閥,使彈簧壓縮或伸長,從而控制車輛高度。 </p><p>  在減震器內設有電動機,電動機受微機的信號控制。利用電動機可以改變通氣孔的大小,從而改變了衰減力的大小。 </p><p>  具體說來,在汽車儀表板上有空氣懸架系統(tǒng)的開關,利用開關可以形成6 種不同的工

14、作方式。</p><p><b>  自動變速器 </b></p><p>  自動變速器的選擋桿相當于手動變速器的變速桿,一般有以下幾個擋位:P(停車)、R(倒擋)、N(空擋)、D(前進)、S(or2,即為2 速擋)、L(or1,即為1 速擋)。這幾個擋位的正確使用對于駕駛自動變速器汽車的人來說尤其重要,下面就讓我們一起來熟悉一下自動變速器各擋位的使用要領。 <

15、;/p><p>  ●P(停車擋)的使用 </p><p>  發(fā)動機運轉時只要選擋桿在行駛位置上,自動變速器汽車就很容易地行走。而停放時,選擋桿必須扳入P 位,從而通過變速器內部的停車制動裝置將輸出軸鎖住,并拉緊手制動,防止汽車移動。 </p><p>  ●R(倒擋)的使用 </p><p>  R位為倒擋,使用中要切記,自動變速器汽車不像手

16、動變速器汽車那樣能夠使用半聯動,故在倒車時要特別注意加速踏板的控制。 </p><p>  ●N(空擋)的使用 </p><p>  N位相當于空擋,可在起動時或拖車時使用。在等待信號或堵車時常常將選擋桿保持在D位,同時踩下制動。若時間很短,這樣做是允許的,但若停止時間長時最好換入N 位,并拉緊手制動。因為選擋桿在行駛位置上,自動變速器汽車一般都有微弱的行駛趨勢,長時間踩住制動等于強行制止

17、這種趨勢,使得變速器油溫升高,油液容易變質。尤其在空調器工作、發(fā)動機怠速較高的情況下更為不利。有些駕駛員為了節(jié)油,在高速行駛或下坡時將選擋桿扳到N 位滑行,這很容易燒壞變速器,因為這時變速器輸出軸轉速很高,而發(fā)動機卻在怠速運轉,油泵供油不足,潤滑狀況惡化,易燒壞變速器。 </p><p>  ●D(前進擋)的使用 </p><p>  正常行駛時將選擋桿放在D 位,汽車可在1~4 擋(或3

18、 擋)之間自動換擋。D位是最常用的行駛位置。需要掌握的是:由于自動變速器是根據油門大小與車速高低來確定擋位的,所以加速踏板操作方法不同,換擋時的車速也不相同。如果起步時迅速將加速踏板踩下,升擋晚,加速能力強,到一定車速后,再將加速踏板很快松開,汽車就能立即升擋,這樣發(fā)動機噪聲小,舒適性好。 </p><p>  D 位的另一個特點是強制低擋,便于高速時超車,在D 位行駛中迅速將加速踏板踩到底,接通強制低擋開關就能

19、自動減擋,汽車很快加速,超車之后松開加速踏板又可自動升擋。 </p><p>  ●S、L 位低擋的使用 </p><p>  自動變速器在S 位或L 位上處于低擋范圍,可以在坡道等情況下使用。下坡時換入S位或L位能充分利用發(fā)動機制動,避免車輪制動器過熱,導致制動效能下降。但是從D位換入S位或L位時,車速不能高于相應的升擋車速,否則發(fā)動機會強烈振動,使變速器油溫急劇上升,甚至會損壞變速器。

20、 </p><p>  另外在雨霧天氣時,若路面附著條件差,可以換入S位或L位,固定在某一低擋行駛,不要使用能自動換擋的位置,以免汽車打滑。同時必須牢記,打滑時可將選擋桿推入N位,切斷發(fā)動機的動力,以保證行車安全。</p><p><b>  附錄二:英文翻譯</b></p><p>  Suspension</p><p&

21、gt;  The modern of in the car has two kinds of suspension, a kind of suspension is from move , another a kind of suspension is active of. </p><p>  From move an a function for, is from spring coil, reducin

22、g flapping machine( reduce to the flap ), leading to organization etc. constituting, it is vibration that impact to dies down roadecause this kind of can produce the function dint by oneself, therefore call active of .Th

23、e active of is more than ten years to develop of, from a kind of new of that computer control, have three terms: </p><p>  (1) have to can produce the motive source of the function dint; </p><p>

24、;  (2) carry out a piece can deliver this kind of function dint combines it can continue the work; </p><p>  (3) have the variety spreads to feel the machine combines to concentrates the relevant data to mic

25、ro-computer to proceed to carry to calculate to combine the decision controls the way.Therefore, active a technique for gathering together mechanics with electronics knowledge, is a kind of high technique that compare t

26、pass the carriage dint, the reduces from the impact dint but causable loading system.Among them the spring coil rises primarily the function that deceleration pound at dint, reduce t</p><p>  But active a de

27、vice for of in the control link installing can producing take out moving, adopt a kind of repress in suppressing the dint by dint the road face the impact dint of the carriage and the inclination dint of the carriage.B o

28、 sophisticate to equip. </p><p>  For example equip active an axis for of France snow iron dragon mulberry,the car's a system is speed, carriage that a micro-computer, have on the of the 5 kinds of sprea

29、ding feels machine, distinguish to deliver to micro-computer the car soon, the ex- round system moves the pressure and step to move the accelerator pedal perpendicular flap and frequencies, change direction the dish angl

30、e and change direction flat-out etc. data directionally.The computer receives these datases continuously and wi</p><p>  Moreover, active a function for having carriage sport of control.When the car system m

31、oves or turns a corner of inertial cause When the spring coil transform, active a dint for would producing first and opposite anti- in the dint of , reduce the variety of the carriage position.For example Germany speeds

32、2000 CLs type sport car, be, the vehicle turns a corner an inclination for spreading feeling machine would immediately examining carriage with horizontal acceleration, computer according to info</p><p>  The

33、 active in car a liquid presses with the air type: </p><p>  From the angle demarcation of the control dint, the of can is divided into passive of , active of in half with active of . Current, the automoti

34、ve a system has the spring coil with reduce to flap the machine mostly, theincapable source inside a system insupplies the device, its flexibility can't change with the exterior work with the , therefore calling that

35、 this kind of is passive of . </p><p>  Active an action for thering is direct dint in conduct and actions taking place machine, can according to input and output the superior feedback of proceeding contro

36、l, making a the of has to reduce to shake the characteristic bestly, toing increase the automotive and going smoothly with manipulate the stability.It constitutes with a dint occurrence machine Fe from the flexibility a

37、C. </p><p>  Half active a spring coil for can seeing making from variable characteristic with machine that reducing and flapping the a system constitutes, although it can't proceed the superior contro

38、l with regulate with the outsider importation, it can press saving under every kind of term of the calculator superior spring coil with reduce to flap the machine excellent to turn the parameter instruction to regulate t

39、he spring coil just a the appearance of for with reducing flapping machine.It from flexibi</p><p>  The electronics technique control car a system is main from( the car is high and change direction the Cape

40、, acceleration, road the estimate) spread to feel the machine, electronics control ECU, of control of carry out machine etc. constitute.The control function of the system usually has below three: 1 the car is high to adj

41、ust to be the car at rise and fall When the uneven road drive, can make carriage jacked up, in order to in pass;When the good road mades good time, can lower the carriage, to</p><p>  2 dint controls is use

42、d to increase to manipulate the stability automotively, in the flashback curved, nasty accelerates to move with the urgent system circumstance next, can rr is to the side , horizontal put the flutter with the control of

43、the carriage can more quick, precision, the car mades good time with the stability exaltation of the turn, carriage side reduce.The ex- in carriage is small when system move, starting with nasty accelerate can after re

44、ducing .Even in the bad road, the flu</p><p>  One.The active type liquid presses of </p><p>  The active type liquid that electronics control presses a quantity for can according to of with a

45、cceleration etc., making use of the liquid press the parts actively automotive vibration in control.The active type liquid presses a the of arrange to is sepress the variety of the carriage. </p><p>  3 s

46、pring coil just a control changes spring coil just degree, make a contented sport or comfortable request. </p><p>  Adopt an empress, cahown as diagram on the car, having in the nearby gearing in center of

47、gravity in car lengthways, horizontal acceleration with horizontal put the top preads to feel machine, use to collect the carriage the vibration, the car wheel jumps about, carriage high degree with tilt to one side appe

48、arance etc. signal, these signalses is inputed control unit ECU, ECU according to input signal with in advance the procedure that set up issues to control the instruction, controling the ser</p><p>  In elec

49、tronics control of active type air a system, tiny machine according to spread to feel the machine changeses to an instruction for issuing the instruction, the of can give according to the tiny machine after delivering o

50、f the signal with the control mode that pilot give has been carries to calculate the analysis of just degree with the coefficient of , is a carriage within the scope of drives to keeps in the process good and stable fun

51、ction, and respond to the vibration of the carriage t</p><p>  1 high control in car;Cent standard, go up with only after going up a three kinds of works appearance; </p><p>  2 reduce the t

52、hat shake the machine reduce the dint control the cent low, inside, high three file; </p><p>  3 the cent of flexibility coefficient of air spring coilses are soft and hard two file. </p><p&

53、gt;  The air an electronics controls the work principle of the system;Use the air compressor formation compressed air, combine to give the compressed air to spring coil with the air room that reducing and shaking the mac

54、hine inside, changes with this the high degree of the vehicle.Fore a neighborhood for with empress round establishes the car the high spreading feels machine, press car the high spreading the exportation signal that feel

55、s the machine, the tiny machine judges the vehicle the high degre</p><p>  Establish the electric motor in reduce shook machine, the electric motor suffers the signal control of the tiny machine.Making use o

56、f the electric motor can change the size of the air hole . Say in a specific way, switch in last free spirit in instrument panel in car a system, make use of the switch can become 6 kinds of different works method. <

57、/p><p>  The automatic gearbox </p><p>  The automatic gearbox chooses to block the pole the equal to moving the stick shift of the gearbox, having generally below several blocks:P( parking), R( p

58、our to block), N( get empty to block), D( go forward), S( or2, namely for 2 block soon), L.( or1, namely for 1 block soon)This several an usage for blocking a right usages coming driver the automatic gearbox is automotiv

59、e of person to say particularly important, underneath let us very much familiar with once automatic gearbox eachly blocking</p><p>  The usage of the P ( the parking blocks) </p><p>  The launc

60、hes the luck turns as long as choose to block the pole in driving the position, automatic gearbox car run about very easily.But park, choose to block the pole must pull into of P, from but pass the internal parking syste

61、m in gearbox moves the device will output the stalk lock lives, combining to tense the hand system move, preventing the car ambulation. </p><p>  The usage of the R( pour to block)</p><p>  R a

62、control for is pouring blocking, using inside wanting slicing recording, automatic gearbox car unlike moving gearbox car so can using half moving, so while reversing the car wanting special attention accelerating pedal.

63、</p><p>  The usage of the N( get empty to block) </p><p>  The N is equal to get empty to block, can while starting or hour of trailer usage.At wait for the signal or block up the car will ofte

64、n often choose to block the pole keeps in the of D, trampling at the same time the next system move.If time is very short, do like this is an admission of, but if stop the time long time had better change into of N, comb

65、ine to tense the hand system moves.Because choose to block the pole in driving the position, the automatic gearbox car has generally and all to dr</p><p>  The usage of the D( go forward to block) </p>

66、<p>  Will choose to block when is normal to drive the pole put in the of D, car can at 1 4 block( or 3 block) its change to block automatically.The of D drives the position most in common usely.What demand contr

67、ol is:Because the automatic gearbox is soon high and low with car to come to make sure to block according to the accelerator size a, so accelerate the pedal operation method is different, changing to block the hour of th

68、e car is soon too not same alike.If start hour quick accelerate the pedal</p><p>  The another characteristics of the D is a compulsory low blocking, easy to high speed the hour overtakes a car, will acceler

69、ate quickly in of D drove the pedal trample after all, connect the compulsory low fend off the pass and then can reduce to block automatically, the car accelerates very quickly, after overtaking a car loosen to open the

70、pedal of acceleration to can rise to block automatically again. </p><p>  The usage of the S, of L low the usage that block </p><p>  The automatic gearbox in in is placed in the low blocking th

71、e scope on of S or of Ls, can usage under an etc. circumstance.It change to can make use of to launch well into of S or of Ls the mechanism move, avoiding the car wheel system move the machine over hot, cause the system

72、 move the effect descent while going down slope.But change into from the of D of S or of L, car soon can't higher than rise to block the car homologously soon, otherwise strong vibration in opportunity to launch, mak

73、e ge</p><p>  The is another at rain fog weather hour, if the road adheres to the term bad, can change into a position for or of L, fixing at somely first lowly blocking driving, doing not use can automatica

74、lly changing blocking, in order to prevent the car beats slippery.Must keep firmly in mind at the same time, beat the slippery hour can will choose to block the pole pushes into a motive for, cutting off launching machin

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