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1、<p><b>  附 錄 Ⅱ</b></p><p>  Bus chassis Summary</p><p>  Bus chassis is the most important part, it has a direct bearing on the performance of bus. China's bus industry star

2、ted late, so far only 20 or so, on our bus chassis development, can be summarized as: late start, poor foundation, rapid development, and gradually narrow the gap between foreign and other features.</p><p> 

3、 Before the 1980s, China's main passenger vehicle chassis modifications. Since slower vehicle speed, vehicle ride is not too high, thus converted into a low-speed bus (maximum 75 kilometers), comfort poor. In 1981 th

4、e original factory in Yangzhou Bus (now Yangzhou Yaxing Bus Co., Ltd.) the successful development of the first bus chassis JT663, and its truck chassis compared to the past, Speed (90 km / h), using a wide front axle for

5、 Lunju bus, cycle-ball steering gear and dual-circuit brake syste</p><p>  In the 1990s, the development of China's highway speed of vehicles by the new requirements, the requirements of the largest vehi

6、cles more than 120 kilometers per hour, normal driving speed of 90 km above. Although at this time many of the domestic passenger business through joint ventures, cooperation or technology transfer and other means to sta

7、rt producing high-speed bus, but due to high cost of these vehicles only on the strength of passenger traffic, operating in economically developed areas</p><p>  "9th Five-Year" period, the industr

8、ial development of China's passenger by the State attaches great importance to the State Economic and Trade Commission will require high standards of the two passenger buses JT6890 Development as a "9th Five-Yea

9、r" technology projects. At the same time with the development and bus chassis production capacity of enterprises, for domestic auto parts production lag, and some trains were unable to meet the needs of the actual s

10、ituation of international procurement, </p><p>  Although China-made bus chassis in recent years developed very quickly, but compared with other countries, whether from the design level or from the assembly

11、of the reliability, the gap is still great, particularly the assembly of the quality and reliability of the more prominent issues . With China's accession to the WTO is approaching, international cooperation will be

12、further expanded, this will benefit China's passenger bus chassis design and assembly of raising the level of production, as s</p><p>  Since the chassis is the largest body parts, body is good or bad is

13、 bound to lead the chassis completely good or bad, a good body is to have high rigidity, the so-called high-rigidity is not deformed. Traffic on the road, with the naked eye looks like no deformation, but in fact will be

14、 the impact of the road because of constant deformation, but a body deformation, vehicles will not be obedient, do not think that the 1 ~ 2 mm no deformation, it will You it difficult to control in high-speed vehi</p&

15、gt;<p>  But here referred to the rigid body has nothing to do with security, if really want to make, of course, can make a very good control with no security of the body, and vice versa. Therefore, the manipulati

16、on of rigid body is not seen by the impact test, usually rigid body with the manipulation of the distorted rigid test of a fixed endpoint of a body, then the diagonal line endpoint SHI Li, the deformation obtained vehicl

17、es Point of view, in units of Nm / deg, this is the depot in the vehicle, of</p><p>  However, regardless of rigid body again, if the suspension arm directly to the car body, also because of stress concentra

18、tion, and have too many local deformation, so the best equipment on the rigid frame of a higher, will be suspended from The strength of the crane through the frame, distributed to more cars on the body to reduce the defo

19、rmation, so that the high-priced cars will not mean trailers loaded deputy, to reduce the pressure faced by the body.</p><p>  Chassis suspension system has always been the most volatile areas, because in ad

20、dition to consider the rigid, point of control is a major challenge, said the first briefing when the steering control, and some cars can be done near real-time responses to some After turning the steering wheel cars onl

21、y about one second reaction (AOL really tried this car), there is such a major difference between the issue or rigid, less than the rigid body and suspension will absorb deformation out to you the act</p><p>

22、;  Of course, in addition to the most basic of steering control, suspension system also controls the wheels of various point of view, the perspective of many of the wheel, the inclination, after the dip, inclination, the

23、 former beam angle. Tire decision, inclination angle of the earth, in theory, the case is 0 °, but the car will roll Guowan, long-term external wear on tires would be more serious, so many negative set point, but al

24、so allows car when stability is Guowan As for the plant to see how m</p><p>  After the dip is a very important point, it affects you when the vehicle to the impression that after the dip for the role of the

25、 former towards the direction of the wheel, which sounds quite vague, with examples to explain! In the column, power forward or North Korea after, so the wheel is Chaoqian Fang, Guowan, Guowan wheels to bear the centrifu

26、gal force, the wheels will move towards the direction of centrifugal force, in the tail flick , The front will also move towards the direction of the t</p><p>  Since before the drive after a small dip, it w

27、ill be less than straight into the stable, so the angle there, the role of the inclination to let the wheels forward, to fill the lack of stability, and this inclination by the Straight power load multiplied by sin (incl

28、ination). In addition, with the inclination angle of inclination angle for tolerance, this perspective is not important, it is important to the projection angle to the length of the ground, known as the length of the tyr

29、e friction rad</p><p>  However, domestic bus chassis in recent years developed very quickly, but compared with other countries, whether from the design level or from the assembly of the reliability, the gap

30、 is still great, particularly the assembly of the quality and reliability of the more prominent issues . With China's accession to the WTO is approaching, international cooperation will be further expanded, this will

31、 benefit China's passenger bus chassis design and assembly of raising the level of production, as soo</p><p><b>  客車(chē)底盤(pán)概述</b></p><p>  底盤(pán)是客車(chē)最重要部分,它直接關(guān)系到客車(chē)的性能。我國(guó)客車(chē)工業(yè)起步較遲,至今才20年左右的時(shí)

32、間,就我國(guó)客車(chē)底盤(pán)的發(fā)展情況而言,可以概括為:起步晚、基礎(chǔ)差、發(fā)展快,和國(guó)外差距逐漸縮小等特征。</p><p>  20世紀(jì)80年代以前,我國(guó)的客車(chē)主要用貨車(chē)底盤(pán)改裝。由于貨車(chē)時(shí)速較慢,車(chē)輛平順性不太高,因而改裝成的客車(chē)時(shí)速低(最高75公里),舒適性差。1981年原揚(yáng)州客車(chē)廠(現(xiàn)為揚(yáng)州亞星客車(chē)股份有限公司)率先研制成功客車(chē)底盤(pán)JT663,它和以往貨車(chē)底盤(pán)相比,速度快(90公里/小時(shí)),采用了寬輪距客車(chē)專用前軸、

33、循環(huán)球式轉(zhuǎn)向器和氣壓雙回路制動(dòng)系統(tǒng),在懸掛系統(tǒng)上也有所突破,已經(jīng)能尋覓到“以人為本”的設(shè)計(jì)理念。JT663的試制成功,標(biāo)志著我國(guó)客車(chē)底盤(pán)的誕生,具有劃時(shí)代的意義。</p><p>  20世紀(jì)90年代,我國(guó)高速公路的發(fā)展對(duì)車(chē)輛的速度提出新的要求,要求</p><p>  車(chē)輛最大時(shí)速120公里以上,正常行駛時(shí)速90公里以上。雖然此時(shí)國(guó)內(nèi)許多客車(chē)企業(yè)通過(guò)合資、合作或技術(shù)引進(jìn)等方式開(kāi)始生產(chǎn)高速

34、客車(chē),但由于成本較高,這些車(chē)只能在實(shí)力雄厚、客運(yùn)量大、經(jīng)濟(jì)發(fā)達(dá)的地區(qū)運(yùn)營(yíng),對(duì)于經(jīng)濟(jì)欠發(fā)達(dá)地區(qū)的多種路面混合線路,缺少合適的車(chē)輛。此時(shí)客車(chē)和底盤(pán)企業(yè)汲?。剩裕叮叮车妆P(pán)設(shè)計(jì)的成功經(jīng)驗(yàn),采取縮短車(chē)身,減輕自重,減少整車(chē)最大總質(zhì)量,增大發(fā)動(dòng)機(jī)功率,提高車(chē)輛比功率等措施,采用整體式動(dòng)力轉(zhuǎn)向機(jī)構(gòu)和噪聲小、散熱快、使用壽命長(zhǎng)的子午線輪胎,設(shè)計(jì)生產(chǎn)出常速大于90公里,最高時(shí)速達(dá)到110公里以上的JS6820底盤(pán)及客車(chē)。因?yàn)樵撥?chē)的主要總成件均為國(guó)產(chǎn)件,價(jià)

35、格只有30多萬(wàn)元,性能價(jià)格比較高,一般客運(yùn)企業(yè)在半年左右即可收回成本,所以深受?chē)?guó)內(nèi)用戶歡迎。</p><p>  “九五”期間,我國(guó)客車(chē)工業(yè)的發(fā)展受到國(guó)家的高度重視,國(guó)家經(jīng)貿(mào)委要求將達(dá)到高二級(jí)客車(chē)標(biāo)準(zhǔn)的JT6890客車(chē)的研制列為“九五”科技項(xiàng)目。同時(shí)具有底盤(pán)開(kāi)發(fā)和客車(chē)生產(chǎn)能力的企業(yè),針對(duì)國(guó)內(nèi)汽車(chē)配件生產(chǎn)滯后、部分總成件性能滿足不了需要的實(shí)際情況,實(shí)行國(guó)際采購(gòu),優(yōu)先選擇即將在中國(guó)合資生產(chǎn)的產(chǎn)品,同時(shí)為國(guó)內(nèi)的汽配生產(chǎn)

36、企業(yè)參與國(guó)際經(jīng)濟(jì)合作牽線搭橋。由于實(shí)行國(guó)際比價(jià)采購(gòu)的方法,新開(kāi)發(fā)的JT6890底盤(pán)控制了較低成本,價(jià)格比同類型進(jìn)口底盤(pán)低45%。1998年底,JT6890經(jīng)過(guò)3萬(wàn)公里的路試,全面通過(guò)國(guó)家鑒定。雖然JT6890底盤(pán)總成件選用了美國(guó)、德國(guó)、瑞典、英國(guó)等6個(gè)國(guó)家20多種總成,但匹配完美,令人稱道。</p><p>  雖然國(guó)產(chǎn)客車(chē)底盤(pán)近年來(lái)發(fā)展很快,但與國(guó)外相比,不論從設(shè)計(jì)水平還是從成件的可靠性來(lái)說(shuō),差距仍還很大,尤其

37、是總成件的質(zhì)量和可靠性的問(wèn)題更為突出。隨著中國(guó)入世的臨近,國(guó)際合作也將進(jìn)一步擴(kuò)大,這將有利于我國(guó)客車(chē)底盤(pán)設(shè)計(jì)水平和客車(chē)總成件生產(chǎn)水平的提高,為盡快縮小同世界先進(jìn)水平的差異帶來(lái)機(jī)遇。</p><p>  既然車(chē)身是底盤(pán)的最大零件,那車(chē)身的好壞勢(shì)必完全主導(dǎo)了底盤(pán)好壞,一個(gè)好的車(chē)身在于擁有高剛性,所謂的高剛性就是不易變形。車(chē)輛行走在路上時(shí),用肉眼看起來(lái)好像完全沒(méi)有變形,但實(shí)際上都會(huì)因?yàn)槁访娴臎_擊而不斷的變形,一但車(chē)身變

38、形,車(chē)輛就不會(huì)聽(tīng)話,不要以為1~2mm的變形沒(méi)什么,它會(huì)讓你在高速時(shí)難以駕馭車(chē)輛,因?yàn)樵诟咚贂r(shí),你對(duì)車(chē)輛的操控也不到10mm,這就是為什么各汽車(chē)媒體常說(shuō),車(chē)身剛性對(duì)于高速行駛的穩(wěn)定性有絕對(duì)性的影響。</p><p>  不過(guò)這里所指的車(chē)身剛性與安全性無(wú)關(guān),若是真的要作,當(dāng)然可以作出一臺(tái)擁有極佳操控性卻沒(méi)安全性的車(chē)身,反之亦然。所以車(chē)身的操控剛性是不可能由撞擊測(cè)試中看出來(lái)的,車(chē)身的操控剛性通常跟扭曲剛性有關(guān),測(cè)試法

39、為固定車(chē)身某一端點(diǎn),然后對(duì)對(duì)角在線的端點(diǎn)施力,求得車(chē)輛的變形角度,單位為Nm/deg,這就是各車(chē)廠在車(chē)輛改款時(shí)常說(shuō)的車(chē)身剛性又提升多少%的計(jì)量單位,可惜的是全世界車(chē)廠對(duì)于這個(gè)數(shù)字保密到家,使得車(chē)身剛性比較只能流于試車(chē)的主觀印象,而沒(méi)有科學(xué)的數(shù)據(jù)比較,再加上懸吊及避震的模糊化之后,車(chē)身剛性變成老王賣(mài)瓜自賣(mài)自夸,謊言攻訐不斷的產(chǎn)生。</p><p>  不過(guò),不論車(chē)身剛性再高,若是直接將懸吊臂接于車(chē)身上,也會(huì)因?yàn)閼?yīng)力

40、集中現(xiàn)象,而產(chǎn)生過(guò)多的局部變形,所以最好裝上剛性更高的副車(chē)架,將來(lái)自懸吊臂的力量透過(guò)副車(chē)架,分散到更多的車(chē)身上以降低車(chē)身的變形量,所以高價(jià)一點(diǎn)的車(chē)都會(huì)不吝嗇裝上副車(chē)架,來(lái)降低車(chē)身所承受的壓力。</p><p>  懸吊系統(tǒng)向來(lái)是底盤(pán)中最變化多端的地方了,因?yàn)槌藙傂缘目紤]外,角度控制也是一大挑戰(zhàn),先說(shuō)最簡(jiǎn)當(dāng)?shù)霓D(zhuǎn)向控制,有的車(chē)就能作到近乎實(shí)時(shí)的反應(yīng),有的車(chē)轉(zhuǎn)動(dòng)方向盤(pán)過(guò)后約一秒才有反應(yīng)(AOL真的試過(guò)這種車(chē)),會(huì)有這

41、種差別主要還是剛性問(wèn)題,剛性不足的車(chē)身和懸吊會(huì)先變形吸收掉你的轉(zhuǎn)向動(dòng)作,然后再反彈出來(lái),開(kāi)到這種車(chē)會(huì)讓人有一種不安定感,實(shí)際上是不信賴感,另外也會(huì)因?yàn)槌跗诘霓D(zhuǎn)向動(dòng)作被吃掉,所以駕駛?cè)说姆较虮P(pán)會(huì)多轉(zhuǎn)一些,導(dǎo)致轉(zhuǎn)向后期的離心力太大導(dǎo)致失控,這種車(chē)開(kāi)久了駕駛技術(shù)就會(huì)錯(cuò)誤,導(dǎo)致容易發(fā)生低速失控的事件。</p><p>  當(dāng)然除了最基礎(chǔ)的轉(zhuǎn)向控制之外,懸吊系統(tǒng)也控制著車(chē)輪各種的角度,有關(guān)車(chē)輪的角度很多,有外傾角、后傾角、

42、內(nèi)傾角、前束角等。外傾角決定輪胎的接地角度,理論上而言是0°,但車(chē)子過(guò)彎時(shí)會(huì)側(cè)傾,長(zhǎng)久下去輪胎外部磨損會(huì)比較嚴(yán)重,所以多設(shè)定一點(diǎn)負(fù)值,也可讓車(chē)在過(guò)彎時(shí)穩(wěn)定一點(diǎn),至于設(shè)多少就看各廠經(jīng)驗(yàn)決定,不過(guò)原廠設(shè)定不適合太保守或太暴力的人,所以根據(jù)自己的開(kāi)車(chē)需求,要求輪胎行作出自己的定位角度是比較好的做法。</p><p>  后傾角是非常重要的角度,它影響著你對(duì)車(chē)輛轉(zhuǎn)向時(shí)的感覺(jué),后傾角的作用為讓前車(chē)輪朝向力的方向,

43、這聽(tīng)起來(lái)是蠻模糊的,所以用實(shí)例解釋吧!在直行時(shí),力量是朝前或是朝后的,所以車(chē)輪是朝前方的,在過(guò)彎時(shí),車(chē)輪承受到過(guò)彎時(shí)的離心力,也會(huì)讓車(chē)輪朝向離心力的方向,在甩尾時(shí),前輪也會(huì)朝向甩尾的方向,于是你知道了為什么出彎的時(shí)候可放掉方向盤(pán)的原因了。不過(guò)后傾角越大,相對(duì)的駕駛?cè)艘昧Φ霓D(zhuǎn)動(dòng)方向盤(pán),所以在前輪有驅(qū)動(dòng)力的車(chē)上,后傾角通常只有1~3°,而后驅(qū)車(chē)通常有5~10°。 </p><p>  既然前驅(qū)

44、車(chē)的后傾角很小,那直進(jìn)穩(wěn)定就會(huì)不足,所以內(nèi)傾角就出現(xiàn)了,內(nèi)傾角的作用為讓車(chē)輪朝前,以補(bǔ)足穩(wěn)定性不足的問(wèn)題,而這個(gè)內(nèi)傾角所產(chǎn)生的直進(jìn)力量為負(fù)重乘以sin(內(nèi)傾角)。另外內(nèi)傾角跟外傾角的夾角為包容角,這個(gè)角度不重要,重要的是該角投影到地面的長(zhǎng)度,該長(zhǎng)度稱為輪胎摩擦半徑,該半徑大小影響著路面感的多寡,不過(guò)太多也會(huì)造成轉(zhuǎn)向阻力。不過(guò)改變輪胎直徑或輪框值都會(huì)改變摩擦半徑,這就是為什么大家都說(shuō)前輪不要亂換的原因。前束角國(guó)內(nèi)多稱為前束,因?yàn)橐郧叭障弟?chē)

45、多以mm為單位,不過(guò)現(xiàn)在幾乎都是以角度為單位了。前束角的作用為讓兩側(cè)車(chē)輪有向內(nèi)的力量,藉此穩(wěn)定住車(chē)身,也是為了直線穩(wěn)定的需求。不過(guò)也有的車(chē)用前展角,這樣在轉(zhuǎn)向初期的反應(yīng)性極高,不過(guò)市售車(chē)上比較少見(jiàn)就是了。雖然還有一些角度沒(méi)講,但了解這些大該就能理解懸吊要作的事了,說(shuō)穿了就是角度控制,角度控制最首要的就是不變形的懸吊系統(tǒng),畢竟一但變形原先設(shè)定的角度就沒(méi)了,不過(guò)現(xiàn)在更進(jìn)步到角度控制,讓車(chē)輛的操控性更好。</p><p&g

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