華晨寶馬齒輪齒條轉(zhuǎn)向器的設(shè)計(jì)【說明書+CAD+SOLIDWORKS】

華晨寶馬齒輪齒條轉(zhuǎn)向器的設(shè)計(jì)【說明書+CAD+SOLIDWORKS】,說明書+CAD+SOLIDWORKS,華晨,寶馬,齒輪,齒條,轉(zhuǎn)向器,設(shè)計(jì),說明書,仿單,cad,solidworks 黑龍江工程學(xué)院本科生畢業(yè)設(shè)計(jì)附錄 AThe active steering system from BMWActive steering system of control components and engine electronic parts, dynamic stability control system (DSC) and two yaw rate sensors connected mutually. On the basis of the system provided information, it with an average of 100 times per second operation speed, provide the most real-time, the most ideal steering Angle. By measuring system, can control the Angle to the drivers intentions. Dynamic stability control system based on the number of turns can calculate the speed, and yaw rate sensor can be monitor the vertical axis of the vehicle stability. For new 5 is running on a line on whether an ideal or on the road of the trend, active steering system always can sensing. When there is a special case of an emergency, such as dodge, all cars will naturally occur oversteer phenomenon. Active steering system at the beginning, and can detect in milliseconds acoordingly adjusted to Angle within. That is, the system can ride in the imperceptible in automatically reversal steering system to balance the body, so as to increase the the security of driving. And if active steering system itself wasnt enough to maintain the stable advanced vehicle route, dynamic stability control system timely intervention, reduce engine will power to impose individual wheel brake or. One thousand control software failure, how to do? BMW engineers had expected to this. In pure line control steering system, electronic control signal to the steering wheel and wheels, between the mechanical structure and not directly connected. Equipped with active steering system of new 5 department is different, even if its system problem, can still be a turn, only the action to Angle cant increase or decrease. For software obstacles and cause serious mistakes is never allowed to happen, Philip kohn doctor explained: all the information in computer in two respectively in a different way to carry on the analysis,only active steering system The results of the two sets of same instructions to be accepted, and if the results of conflict, the system will will be closed. Mechanical and electronic device that clever apply bring out the best in each other, BMW to becoming the first corner flexibility and fusion in a car until stability. When the driver removes steering wheel turned an Angle, it turned to the wheel will will deflect a fixed Angle. Drivers in turning process, need to change, according to gently road speed change and other factors, and constantly through the rotating steering wheel to adjust the Angle of steering wheel, maintain the drivers of the track to wish to turn to. The traditional steering system has its own advantages, such as reliable, low failure rate to, there exist some disadvantages, that is steering transmission ratio if is larger, vehicles in low speed to more light, but in high speed to appears too sensitive, steering stability becomes poor. If, on the other hand, turned to the transmission ratio, high speed in smaller vehicles to will appear sedate, but in low speed state, will be hard to. The characteristics of the largest active steering system, be according to the driving conditions, automatic regulation vehicles, and transmission ratio to increase or decrease the front wheel steering Angle. In the low speed, the role of the motor with drivers steering wheel rotation of the direction, steering transmission ratio increases, can reduce the demand for drivers to force. In high speed of operation, motor direction and the drivers in opposite directions, steering wheel rotation this reduced the front wheel steering Angle, to reduce the transmission ratio, steering stability improved. In addition to the more comfortable, more flexible, active steering system outside and the important thing is that the more security, which mainly embodies in the vehicle in the high-speed turned suddenly. For example in the highway a high speed suddenly to go beyond looped a car and then returned to the driveway, or in a high speed suddenly found the obstacles to a sharp turn, it is easy to appear understeer or to excessive, vehicles will deviate from the direction of his book, may lose control. In this case, usually the DSC larger superkings cars BMW system through the intervention process control vehicle braking stability, will greatly reduce traffic speed, increased energy consumption. And active steering system to start from a judge will turn to appeared after the case, through the electronic control mechanical regulation of device automatic correction to reduce the yaw Angle, intervention occurred. And DSC system in other cars dont have to like driving, ensure intervention of driving stability. However, when active steering system can not complete the control of vehicle, DSC system will participate in to work. Therefore, active steering system need and DSC system to cooperate to use. 附錄 B來自寶馬的主動(dòng)轉(zhuǎn)向系統(tǒng)主動(dòng)式轉(zhuǎn)向系統(tǒng)的控制組件與引擎的電子零件、動(dòng)態(tài)穩(wěn)定控制系統(tǒng)(DSC)和兩只偏航率傳感器相聯(lián)相通。依據(jù)這些系統(tǒng)提供的信息，它以平均每秒100次的運(yùn)算速度，提供最實(shí)時(shí)、最理想的轉(zhuǎn)向角度。系統(tǒng)通過測量轉(zhuǎn)向角度，可以掌握駕駛者的意圖。動(dòng)態(tài)穩(wěn)定控制系統(tǒng)依據(jù)車輪轉(zhuǎn)動(dòng)的圈數(shù)可以計(jì)算出車速，而偏航率傳感器則可隨時(shí)監(jiān)控車輛垂直軸的穩(wěn)定性。對(duì)于新5系是否行駛在理想線路上或是有偏離路線的趨勢，主動(dòng)式轉(zhuǎn)向系統(tǒng)始終都能明察秋毫。 當(dāng)發(fā)生特別緊急的情況時(shí)，例如閃避，所有的汽車都會(huì)自然地發(fā)生轉(zhuǎn)向過度的現(xiàn)象。主動(dòng)式轉(zhuǎn)向系統(tǒng)在一開始就能察覺，并于毫秒之內(nèi)相應(yīng)地調(diào)整轉(zhuǎn)向角度。也就是說，系統(tǒng)能在駕乘者不知不覺中自動(dòng)地反轉(zhuǎn)轉(zhuǎn)向系統(tǒng)來平衡車身，從而提高了行車安全性。而如果主動(dòng)式轉(zhuǎn)向系統(tǒng)自身不足以讓車輛維持穩(wěn)定的先進(jìn)路線時(shí)，動(dòng)態(tài)穩(wěn)定控制系統(tǒng)將及時(shí)介入，降低引擎馬力或?qū)€(gè)別車輪施以剎車。 萬一控制軟件失效了，怎么辦？寶馬工程師早已料想到這點(diǎn)。在純粹的線控轉(zhuǎn)向系統(tǒng)中，轉(zhuǎn)向由電子信號(hào)控制，方向盤與車輪之間并沒有直接的機(jī)械結(jié)構(gòu)相聯(lián)。配備主動(dòng)式轉(zhuǎn)向系統(tǒng)的新5系則與其不同，即使系統(tǒng)發(fā)生故障，仍然能進(jìn)行轉(zhuǎn)向動(dòng)作，只不過其轉(zhuǎn)向角度無法增加或減少。因軟件障礙而造成嚴(yán)重的轉(zhuǎn)向失誤也是絕對(duì)不允許發(fā)生的，菲利普孔恩博士解釋道：所有的信息分別在兩臺(tái)計(jì)算機(jī)中以不同方式進(jìn)行分析，只有兩臺(tái)的結(jié)果相同時(shí)指令才被接受，如果結(jié)果出現(xiàn)矛盾，系統(tǒng)就會(huì)自行關(guān)閉。 機(jī)械與電子裝置的巧妙運(yùn)用相得益彰，使得寶馬成為第一家融合彎道靈活性與直道穩(wěn)定性于一車的公司。 當(dāng)駕駛者將轉(zhuǎn)向盤轉(zhuǎn)過一個(gè)角度，那轉(zhuǎn)向輪必然就會(huì)偏轉(zhuǎn)一個(gè)固定的角度。駕駛者在轉(zhuǎn)彎過程中，需要根據(jù)路面彎度變化、車速變化等因素，不斷通過轉(zhuǎn)動(dòng)轉(zhuǎn)向盤來調(diào)整轉(zhuǎn)向輪的角度，維持駕駛者希望達(dá)到的轉(zhuǎn)向軌跡。傳統(tǒng)的轉(zhuǎn)向系統(tǒng)有它自身的優(yōu)點(diǎn)，如轉(zhuǎn)向可靠、故障率低等，同時(shí)也存在一定的弊病，那就是轉(zhuǎn)向傳動(dòng)比如果較大，則車輛在低速下轉(zhuǎn)向比較輕便，但在高速狀態(tài)下轉(zhuǎn)向則顯得過于靈敏，轉(zhuǎn)向穩(wěn)定性變差。相反，如果轉(zhuǎn)向傳動(dòng)比較小，車輛在高速時(shí)轉(zhuǎn)向會(huì)顯得穩(wěn)重，但在低速狀態(tài)下，轉(zhuǎn)向會(huì)比較吃力。 主動(dòng)轉(zhuǎn)向系統(tǒng)最大的特點(diǎn)，就是依據(jù)駕駛條件，自動(dòng)調(diào)節(jié)車輛轉(zhuǎn)向傳動(dòng)比，從而增加或減小前輪的轉(zhuǎn)向角度。在低速時(shí)，電動(dòng)機(jī)的作用與駕駛者轉(zhuǎn)動(dòng)轉(zhuǎn)向盤的方向一致，轉(zhuǎn)向傳動(dòng)比增大，可以減少駕駛者對(duì)轉(zhuǎn)向力的需求。在高速時(shí)，電動(dòng)機(jī)的運(yùn)轉(zhuǎn)方向與駕駛者轉(zhuǎn)動(dòng)轉(zhuǎn)向盤方向相反，這減少了前輪的轉(zhuǎn)向角度，轉(zhuǎn)向傳動(dòng)比減小，轉(zhuǎn)向穩(wěn)定性提高。 除了更舒適、更靈活之外，主動(dòng)轉(zhuǎn)向系統(tǒng)還有很重要的一點(diǎn)就是更安全，這一點(diǎn)主要體現(xiàn)在車輛高速行駛中的突然轉(zhuǎn)向。例如在公路上高速行駛時(shí)突然變線以超越另一輛車然后回到車道時(shí)，或者高速行駛中突然發(fā)現(xiàn)前方有障礙物需要急轉(zhuǎn)彎時(shí)，很容易出現(xiàn)轉(zhuǎn)向不足或者轉(zhuǎn)向過度，車輛將偏離自己預(yù)定的方向，可能失去控制。在這種情況下，通常寶馬車系的DSC系統(tǒng)通過干預(yù)制動(dòng)過程控制車輛的穩(wěn)定，行車速度將大幅度降低，增加能量的損耗。而主動(dòng)式轉(zhuǎn)向系統(tǒng)從轉(zhuǎn)向一開始就會(huì)判斷轉(zhuǎn)向后出現(xiàn)的情況，通過電子控制的機(jī)械調(diào)控器自動(dòng)修正轉(zhuǎn)向角度，干預(yù)降低偏航情況的發(fā)生。而DSC系統(tǒng)不必像在其他車輛中那樣干預(yù)駕駛，保證車輛行駛的平穩(wěn)性。不過，當(dāng)主動(dòng)轉(zhuǎn)向系統(tǒng)無法完成對(duì)車輛的控制時(shí)，DSC系統(tǒng)將參與到工作中來。因此，主動(dòng)轉(zhuǎn)向系統(tǒng)需要與DSC系統(tǒng)配合使用。4中文譯文汽車電動(dòng)助力轉(zhuǎn)向系統(tǒng)的研究隨著汽車電子技術(shù)的迅猛發(fā)展,人們對(duì)汽車轉(zhuǎn)向操縱性能的要求也日益提高。汽車轉(zhuǎn)向系統(tǒng)已從傳統(tǒng)機(jī)械轉(zhuǎn)向、液壓助力轉(zhuǎn)向(Hydraulic Power Steering ,簡稱HPS) 電控液壓助力轉(zhuǎn)向( Electric Hydraulic Power Steering , 簡稱EHPS) , 發(fā)展到電動(dòng)助力轉(zhuǎn)向系統(tǒng)(Electric Power Steering ,簡稱EPS) ,最終還將過渡到線控轉(zhuǎn)向系統(tǒng)(Steer By Wire ,簡稱SBW)。機(jī)械轉(zhuǎn)向系統(tǒng)是指以駕駛員的體力作為轉(zhuǎn)向能源,其中所有傳力件都是機(jī)械的,汽車的轉(zhuǎn)向運(yùn)動(dòng)是由駕駛員操縱方向盤,通過轉(zhuǎn)向器和一系列的桿件傳遞到轉(zhuǎn)向車輪而實(shí)現(xiàn)的。機(jī)械轉(zhuǎn)向系由轉(zhuǎn)向操縱機(jī)構(gòu)、轉(zhuǎn)向器和轉(zhuǎn)向傳動(dòng)機(jī)械3大部分組成。通常根據(jù)機(jī)械式轉(zhuǎn)向器形式可以分為:齒輪齒條式、循環(huán)球式、蝸桿滾輪式、蝸桿指銷式。應(yīng)用最廣的兩種是齒輪齒條式和循環(huán)球式(用于需要較大的轉(zhuǎn)向力時(shí)) 。在循環(huán)球式轉(zhuǎn)向器中,輸入轉(zhuǎn)向圈與輸出的轉(zhuǎn)向搖臂擺角是成正比的;在齒輪齒條式轉(zhuǎn)向器中,輸入轉(zhuǎn)向圈數(shù)與輸出的齒條位移是成正比的。循環(huán)球式轉(zhuǎn)向器由于是滾動(dòng)摩擦形式,因而正傳動(dòng)效率很高,操作方便且使用壽命長,而且承載能力強(qiáng),故廣泛應(yīng)用于載貨汽車上。齒輪齒條式轉(zhuǎn)向器與循環(huán)球式相比,最大特點(diǎn)是剛性大,結(jié)構(gòu)緊湊重量輕,且成本低。由于這種方式容易由車輪將反作用力傳至轉(zhuǎn)向盤,所以具有對(duì)路面狀態(tài)反應(yīng)靈敏的優(yōu)點(diǎn),但同時(shí)也容易產(chǎn)生打手和擺振等現(xiàn)象,且其承載效率相對(duì)較弱,故主要應(yīng)用于小汽車及輕型貨車上,目前大部分低端轎車采用的就是齒輪齒條式機(jī)械轉(zhuǎn)向系統(tǒng)。隨著車輛載重的增加以及人們對(duì)車輛操縱性能要求的提高,簡單的機(jī)械式轉(zhuǎn)向系統(tǒng)已經(jīng)無法滿足需要,動(dòng)力轉(zhuǎn)向系統(tǒng)應(yīng)運(yùn)而生,它能在駕駛員轉(zhuǎn)動(dòng)方向盤的同時(shí)提供助力,動(dòng)力轉(zhuǎn)向系統(tǒng)分為液壓轉(zhuǎn)向系統(tǒng)和電動(dòng)轉(zhuǎn)向系統(tǒng)2種。其中液壓轉(zhuǎn)向系統(tǒng)是目前使用最為廣泛的轉(zhuǎn)向系統(tǒng)。液壓轉(zhuǎn)向系統(tǒng)在機(jī)械系統(tǒng)的基礎(chǔ)上增加了液壓系統(tǒng),包括液壓泵、V 形帶輪、油管、供油裝置、助力裝置和控制閥。它借助于汽車發(fā)動(dòng)機(jī)的動(dòng)力驅(qū)動(dòng)液壓泵、空氣壓縮機(jī)和發(fā)電機(jī)等,以液力、氣力或電力增大駕駛員操縱前輪轉(zhuǎn)向的力量,使駕駛員可以輕便靈活地操縱汽車轉(zhuǎn)向,減輕了勞動(dòng)強(qiáng)度,提高了行駛安全性。液壓助力轉(zhuǎn)向系統(tǒng)從發(fā)明到現(xiàn)在已經(jīng)有了大約半個(gè)世紀(jì)的歷史,可以說是一種較為完善的系統(tǒng),由于其工作可靠、技術(shù)成熟至今仍被廣泛應(yīng)用。它由液壓泵作為動(dòng)力源,經(jīng)油管道控制閥向動(dòng)力液壓缸供油,通過活塞桿帶動(dòng)轉(zhuǎn)向機(jī)構(gòu)動(dòng)作,可通過改變缸徑及油壓的大小來改變助力的大小,由此達(dá)到轉(zhuǎn)向助力的作用。傳統(tǒng)液壓式動(dòng)力轉(zhuǎn)向系統(tǒng)一般按液流的形式可以分為:常流式和常壓式2 種類型,也可根據(jù)控制閥形式分為轉(zhuǎn)閥式和滑閥式。隨著液壓動(dòng)力轉(zhuǎn)向系統(tǒng)在汽車上的日益普及,人們對(duì)操作時(shí)的輕便性和路感的要求也日益提高,然而液壓動(dòng)力轉(zhuǎn)向系統(tǒng)卻存在許多的缺點(diǎn): 由于其本身的結(jié)構(gòu)決定了其無法保證車輛在任何工況下轉(zhuǎn)動(dòng)轉(zhuǎn)向盤時(shí),都有較理想的操縱穩(wěn)定性,即無法同時(shí)保證低速時(shí)的轉(zhuǎn)向輕便性和高速時(shí)的操縱穩(wěn)定性; 汽車的轉(zhuǎn)向特性受駕駛員駕駛技術(shù)的影響嚴(yán)重; 轉(zhuǎn)向傳動(dòng)比固定,使汽車轉(zhuǎn)向響應(yīng)特性隨車速、側(cè)向加速度等變化而變化,駕駛員必須提前針對(duì)汽車轉(zhuǎn)向特性幅值和相位的變化進(jìn)行一定的操作補(bǔ)償,從而控制汽車按其意愿行駛。這樣增加了駕駛員的操縱負(fù)擔(dān),也使汽車轉(zhuǎn)向行駛中存在不安全隱患;而此后出現(xiàn)了電控液壓助力系統(tǒng),它在傳統(tǒng)的液壓動(dòng)力轉(zhuǎn)向系統(tǒng)的基礎(chǔ)上增加速度傳感器,使汽車能夠隨著車速的變化自動(dòng)調(diào)節(jié)操縱力的大小,在一定程度上緩和了傳統(tǒng)的液壓轉(zhuǎn)向系統(tǒng)存在的問題。目前我國生產(chǎn)的商用車和轎車上采用的大多是電控液壓助力轉(zhuǎn)向系統(tǒng),它是比較成熟和應(yīng)用廣泛的轉(zhuǎn)向系統(tǒng)。盡管電控液壓助力裝置從一定程度上緩解了傳統(tǒng)的液壓轉(zhuǎn)向中輕便性和路感之間的矛盾,然而它還是沒有從根本上解決HPS 系統(tǒng)存在的不足,隨著汽車微電子技術(shù)的發(fā)展,汽車燃油節(jié)能的要求以及全球性倡導(dǎo)環(huán)保,其在布置、安裝、密封性、操縱靈敏度、能量消耗、磨損與噪聲等方面的不足已越來越明顯,轉(zhuǎn)向系統(tǒng)向著電動(dòng)助力轉(zhuǎn)向系統(tǒng)發(fā)展。電動(dòng)助力轉(zhuǎn)向系統(tǒng)是現(xiàn)在汽車轉(zhuǎn)向系統(tǒng)的發(fā)展方向,其工作原理是:EPS 系統(tǒng)的ECU 對(duì)來自轉(zhuǎn)向盤轉(zhuǎn)矩傳感器和車速傳感器的信號(hào)進(jìn)行分析處理后,控制電機(jī)產(chǎn)生適當(dāng)?shù)闹D(zhuǎn)矩,協(xié)助駕駛員完成轉(zhuǎn)向操作。近幾年來,隨著電子技術(shù)的發(fā)展,大幅度降低EPS的成本已成為可能,日本的大發(fā)汽車公司、三菱汽車公司、本田汽車公司、美國的Delphi 汽車系統(tǒng)公司、TRW公司及德國的ZF 公司都相繼研制出EPS。Mercedes2Benz 和Siemens Automotive 兩大公司共同投資6500萬英鎊用于開發(fā)EPS ,目標(biāo)是到2002 年裝車,年產(chǎn)300 萬套,成為全球EPS 制造商。到目前為止,EPS 系統(tǒng)在輕微型轎車、廂式車上得到廣泛的應(yīng)用,并且每年以300 萬臺(tái)的速度發(fā)展。.轉(zhuǎn)向是一個(gè)專業(yè)術(shù)語,適用于采集部件,聯(lián)系等,其中允許一艘(艦船)或汽車(轎車)按照預(yù)期的方向行駛. 一個(gè)例外的情況是鐵路運(yùn)輸由路軌組合在一起鐵路道岔提供轉(zhuǎn)向功能。許多現(xiàn)代轎車使用齒輪齒條式轉(zhuǎn)向器,在方向盤末端有轉(zhuǎn)動(dòng)齒輪;該齒輪帶動(dòng)齒條移動(dòng),它是一種線性的齒輪緊密配合,從一邊到一邊。這種運(yùn)動(dòng)把轉(zhuǎn)矩通過轉(zhuǎn)向橫拉桿和一種叫做轉(zhuǎn)向節(jié)臂的短形臂傳遞給轉(zhuǎn)向輪的主銷。以前的設(shè)計(jì)往往采用循環(huán)球式轉(zhuǎn)向器,而這種轉(zhuǎn)向器仍然應(yīng)用在卡車和多用途車輛。這是一種老式的螺母和齒扇設(shè)計(jì)，該轉(zhuǎn)向管柱轉(zhuǎn)動(dòng)大螺絲(蝸輪),它與一個(gè)齒扇齒輪嚙合,當(dāng)蝸輪轉(zhuǎn)動(dòng)時(shí)，齒扇也隨之轉(zhuǎn)動(dòng)，一個(gè)安裝在齒扇軸上且與轉(zhuǎn)向聯(lián)動(dòng)有關(guān)的搖臂帶動(dòng)轉(zhuǎn)向節(jié)臂 ,從而使車輪轉(zhuǎn)動(dòng). 循環(huán)球式轉(zhuǎn)向器通過安裝滾珠減少螺母和螺桿之間的摩擦;兩根導(dǎo)管和螺母內(nèi)的螺旋管狀通道組合成兩條各自獨(dú)立的封閉的鋼球“流到”。齒輪齒條式轉(zhuǎn)向器設(shè)計(jì)具有很大程度的反饋和直接轉(zhuǎn)向路感;它也通常不會(huì)有任何反彈,或呆滯。缺點(diǎn)是,它是不可調(diào)的,因此當(dāng)它磨損唯一的解決辦法更換。循環(huán)球式轉(zhuǎn)向器的優(yōu)點(diǎn)是機(jī)械優(yōu)勢,因此,它被使用在較大較重的車輛,而齒輪齒條式原本僅限于較小和較輕;由于幾乎普遍采用動(dòng)力轉(zhuǎn)向系統(tǒng),不過,這已不再是一個(gè)重要的優(yōu)勢,導(dǎo)致越來越多地在新型汽車應(yīng)用齒輪齒條式轉(zhuǎn)向器。 循環(huán)球式轉(zhuǎn)向器設(shè)計(jì)在中心也有明顯的沖擊,或死點(diǎn)。凡一分鐘交替方向盤出不來并不移動(dòng)轉(zhuǎn)向機(jī)構(gòu);這是很容易可調(diào)螺桿的端部來減少磨損,但它并不能完全消除或機(jī)制開始磨損很快。 這項(xiàng)設(shè)計(jì)目前仍在使用中,在卡車和其他大型車輛,也應(yīng)用于迅速轉(zhuǎn)向,路感與穩(wěn)健性,可維護(hù)性,和機(jī)械的優(yōu)勢相比不太重要的場合。 較小程度的反饋,這樣的設(shè)計(jì)也有時(shí)是一種優(yōu)點(diǎn);當(dāng)前輪碰撞時(shí)，使用齒輪齒條轉(zhuǎn)向的司機(jī)只有自己的大拇指受傷,造成方向盤揭開一邊突然(因?yàn)轳{駛教練告訴學(xué)生把自己的大拇指在前面的方向盤,而非放在左右的內(nèi)邊緣).這種效果在像卡車一樣的重型汽車更為明顯;循環(huán)球式轉(zhuǎn)向防止這種程度的反饋,只是因?yàn)樗梢栽谡Ｇ闆r下防止可取反饋。 轉(zhuǎn)向連鎖連接轉(zhuǎn)向器和車輪通常符合一個(gè)阿克曼轉(zhuǎn)向幾何的變化,它交代了一個(gè)事實(shí):當(dāng)轉(zhuǎn)向是,內(nèi)輪轉(zhuǎn)過的半徑比外輪小得多，因此適合駕駛的直路,是不適合曲折。由于車輛已成為較重而改用前輪驅(qū)動(dòng),為了扭轉(zhuǎn)方向盤，通常的,主要的是體力。為了解決這一問題,汽車業(yè)發(fā)展的動(dòng)力轉(zhuǎn)向系統(tǒng)。 有兩種類型的助力轉(zhuǎn)向系統(tǒng)-液壓和電氣/電子。 T還有一種液壓-電動(dòng)混合系統(tǒng)。液壓助力轉(zhuǎn)向系統(tǒng)(hps)利用油壓供應(yīng)的一個(gè)發(fā)動(dòng)機(jī)驅(qū)動(dòng)泵,以協(xié)助將方向盤轉(zhuǎn)轉(zhuǎn)動(dòng)。 電動(dòng)助力轉(zhuǎn)向系統(tǒng)(EPS)方式,是較有效率的液壓助力轉(zhuǎn)向系統(tǒng),由于電動(dòng)助力轉(zhuǎn)向汽車只需要提供協(xié)助時(shí),方向盤被轉(zhuǎn)動(dòng),而液壓泵必須不斷運(yùn)行。 在EPS的幫助下是很容易調(diào)節(jié)車型,最高車速,甚至駕駛的喜好。 另外一個(gè)好處是,通過泄漏和處置動(dòng)力轉(zhuǎn)向液消除對(duì)環(huán)境構(gòu)成危險(xiǎn) 。A動(dòng)力轉(zhuǎn)向的分支是速度可調(diào)轉(zhuǎn)向而轉(zhuǎn)向是大量輔助以低速行駛,稍微協(xié)助高速。 汽車制造商認(rèn)為,當(dāng)要停車時(shí)駕駛?cè)丝赡苄枰龀龃罅哭D(zhuǎn)向投入，但當(dāng)時(shí)高速行駛時(shí)則不然。第一輛有這特點(diǎn)的汽車,是雪鐵龍與其diravi，雖然改變了現(xiàn)代汽車轉(zhuǎn)向系統(tǒng)資金的投入，但它改變了定心凸輪的壓力，使得方向盤盡力去回到原來的位置?，F(xiàn)代速度可調(diào)式動(dòng)力轉(zhuǎn)向系統(tǒng),當(dāng)速度增長時(shí)減少了活塞的壓力 ,給予更直接的感受。這一特點(diǎn)在所有新車正逐漸成為司空見慣。 四輪轉(zhuǎn)向(或全輪轉(zhuǎn)向)是一種系統(tǒng),當(dāng)高速行駛時(shí)能增加車輛穩(wěn)定型，而在低速行駛時(shí)可以減小轉(zhuǎn)彎半徑。大多數(shù)的四輪轉(zhuǎn)向系統(tǒng),后輪轉(zhuǎn)向通過單片機(jī)和驅(qū)動(dòng)器實(shí)現(xiàn)。 后輪一般不能反過來,有幾個(gè)系統(tǒng),包括Delphi的quadrasteer，該系統(tǒng)在本田的生產(chǎn)前線，當(dāng)前輪低速時(shí)，允許后輪在相反方向轉(zhuǎn)向。這使得車輛轉(zhuǎn)彎半徑較小,有時(shí)應(yīng)用于大型卡車車輛及掛車。 電子動(dòng)力轉(zhuǎn)向系統(tǒng)圖1電子動(dòng)力轉(zhuǎn)向系統(tǒng)的工作原理電子動(dòng)力轉(zhuǎn)向系統(tǒng)是通過一個(gè)電動(dòng)機(jī)來驅(qū)動(dòng)動(dòng)力方向盤液壓泵或直接驅(qū)動(dòng)轉(zhuǎn)向聯(lián)動(dòng)裝置。電子動(dòng)力轉(zhuǎn)向的功能由于不依賴于發(fā)動(dòng)機(jī)轉(zhuǎn)速，所以能節(jié)省能源電子動(dòng)力轉(zhuǎn)向系統(tǒng)是這樣運(yùn)行的傳統(tǒng)的動(dòng)力方向盤系統(tǒng)使用一條引擎輔助傳送帶駕駛泵浦，提供操作在動(dòng)力方向盤齒輪或作動(dòng)器的一個(gè)活塞協(xié)助司機(jī)的被加壓的流體。在電動(dòng)液壓的指點(diǎn)，一個(gè)電子動(dòng)力方向盤概念使用一臺(tái)電動(dòng)機(jī)駕駛的一個(gè)高效率泵浦。 泵浦速度是由一個(gè)電控制器調(diào)控的變化泵浦壓力和流程，提供被剪裁的指點(diǎn)努力為不同的駕駛的情況。 泵浦可以跑在低速或關(guān)閉提供節(jié)能在大多時(shí)間在多數(shù)世界市場上)直向前的駕駛期間(直接電指點(diǎn)使用一臺(tái)電動(dòng)機(jī)附加指點(diǎn)機(jī)架通過齒輪機(jī)構(gòu)(沒有泵浦或流體)。 各種各樣的馬達(dá)類型和齒輪驅(qū)動(dòng)是可能的。 微處理器控制指點(diǎn)動(dòng)力學(xué)和司機(jī)努力。 輸入包括車速和指點(diǎn)、輪子扭矩，角位和轉(zhuǎn)動(dòng)率。工作運(yùn)行時(shí)的具體細(xì)節(jié)：A “指點(diǎn)傳感器”位于它進(jìn)入傳動(dòng)箱住房的輸入軸。 指點(diǎn)傳感器實(shí)際上是在一個(gè)的二個(gè)傳感器： 那“扭矩的傳感器”轉(zhuǎn)換指點(diǎn)扭矩輸入和它的方向成電壓信號(hào)，并且那“自轉(zhuǎn)的傳感器”轉(zhuǎn)換轉(zhuǎn)動(dòng)速度和方向成電壓信號(hào)。 分享同一套住房的“接口”電路轉(zhuǎn)換從扭矩傳感器和自轉(zhuǎn)傳感器的信號(hào)成控制電子學(xué)可能處理的信號(hào)。從指點(diǎn)傳感器的輸入由那微處理器的控制單元消化也監(jiān)測從車速傳感器的輸入。 傳感器輸入然后被比較確定多少機(jī)械化根據(jù)一張被預(yù)編程序的“力量地圖”需要在控制單元的記憶。 控制單元然后派出適當(dāng)?shù)拿顚?duì)然后供給電動(dòng)機(jī)以潮流的“電源裝置”。 馬達(dá)推擠機(jī)架在右邊或左根據(jù)哪個(gè)方式電壓流動(dòng)(扭轉(zhuǎn)潮流扭轉(zhuǎn)方向馬達(dá)旋轉(zhuǎn))。 增加潮流對(duì)馬達(dá)增加功率協(xié)助。系統(tǒng)有三種操作方式： 左邊或右邊機(jī)械化提供以回應(yīng)從指點(diǎn)扭矩和自轉(zhuǎn)傳感器的輸入的輸入的“正常”控制方式; 被用于在完成輪以后協(xié)助指點(diǎn)回歸的“回歸”控制方式; 并且改變與車速改進(jìn)路感受和挫傷傭金的“更加潮濕的”控制方式。如果方向盤被轉(zhuǎn)動(dòng)，并且舉行在充分鎖位置和指點(diǎn)協(xié)助到達(dá)最大值，控制單元使潮流降低到電動(dòng)機(jī)防止也許損壞馬達(dá)的超載情況。 控制單元也被設(shè)計(jì)保護(hù)馬達(dá)以防止電壓浪涌免受一個(gè)有毛病的交流發(fā)電機(jī)或充電的問題。電子轉(zhuǎn)向控制單位有能力在自我診斷的缺點(diǎn)通過監(jiān)測系統(tǒng)輸入和產(chǎn)品和電動(dòng)機(jī)的激勵(lì)電流上。 如果問題發(fā)生，控制單元通過開動(dòng)在電源裝置的一個(gè)故障自動(dòng)保險(xiǎn)的中轉(zhuǎn)關(guān)閉系統(tǒng)。 這消滅所有機(jī)械化，造成系統(tǒng)恢復(fù)回到手工指點(diǎn)。 破折號(hào)EPS警告燈也被闡明警告司機(jī)。 要診斷問題，技術(shù)員跳服務(wù)檢查連接器的終端并且讀出問題代碼。 圖 2電子動(dòng)力方向盤機(jī)制當(dāng)前發(fā)明與提供的供給動(dòng)力的援助一電子功率驅(qū)動(dòng)器馬達(dá)關(guān)連給車操縱機(jī)構(gòu)。根據(jù)當(dāng)前發(fā)明的一個(gè)方面，那里為提供供給動(dòng)力的援助提供一個(gè)電子功率驅(qū)動(dòng)器機(jī)制給有車的操縱機(jī)構(gòu)一名手動(dòng)地可旋轉(zhuǎn)的成員為操作操縱機(jī)構(gòu)、傳動(dòng)機(jī)構(gòu)包括可行扭矩的傳感器感覺手動(dòng)地被申請于可旋轉(zhuǎn)的成員的扭矩，一個(gè)電子功率驅(qū)動(dòng)器馬達(dá)操縱著被連接到可旋轉(zhuǎn)的成員和安排控制主驅(qū)動(dòng)電動(dòng)機(jī)自轉(zhuǎn)速度和方向以回應(yīng)從扭矩傳感器收到的信號(hào)的控制器，扭矩傳感器包括為與可旋轉(zhuǎn)的成員的連接適應(yīng)的傳感器軸形成引伸因此，以便扭矩通過前述傳感器軸被傳送，當(dāng)時(shí) 可旋轉(zhuǎn)的成員被轉(zhuǎn)動(dòng)，并且應(yīng)變儀在導(dǎo)致的信號(hào)傳感器軸手動(dòng)地登上表示通過前述軸被傳送的相當(dāng)數(shù)量扭矩。 圖3傳感器軸不旋轉(zhuǎn)更好地登上在一個(gè)軸向末端在第一名聯(lián)結(jié)成員和不旋轉(zhuǎn)地登上在它的相反軸向末端在第二名聯(lián)結(jié)成員，第一和第二名聯(lián)結(jié)成員相互允諾允許有限的自轉(zhuǎn)之間連接，以便在一個(gè)被預(yù)先決定的極限之下的扭矩由僅傳感器軸傳送，并且，以便在前述被預(yù)先決定的極限之上的扭矩通過第一和第二名聯(lián)結(jié)成員被傳送。更適宜地安排第一和第二名聯(lián)結(jié)成員作為操縱的連接的第一和第二個(gè)部分的一座橋梁互相的旋轉(zhuǎn)式成員。合適的傳感器軸是通常在多數(shù)的長方形橫斷面它的長度中。應(yīng)變儀包括一個(gè)或更多的適應(yīng)地看見了諧振器綁到傳感器軸上。好的馬達(dá)操縱的被連接到可旋轉(zhuǎn)的成員通過傳動(dòng)器。馬達(dá)更好地包括一個(gè)工具箱和同心地被安排相對(duì)可旋轉(zhuǎn)的成員。當(dāng)前發(fā)明的Various方面此后將描述，關(guān)于伴隨的圖畫， ：圖1是一個(gè)車操縱機(jī)構(gòu)的一個(gè)圖表看法包括一個(gè)電子功率驅(qū)動(dòng)器機(jī)制根據(jù)當(dāng)前發(fā)明，圖 2是說明在圖顯示的傳動(dòng)機(jī)構(gòu)的各種各樣的組分的之間流程圖互作用1上，圖 3是一個(gè)軸截面通過在圖顯示的傳動(dòng)機(jī)構(gòu)1，圖4上是一張截面圖被采取沿著線IV-IV在表3，圖5是在圖顯示的輸入推進(jìn)聯(lián)結(jié)的一張更加詳細(xì)的分解圖3上，和圖 6是顯示在表3.的傳動(dòng)器的一張更加詳細(xì)的分解圖。 圖1的最初Referring，那里顯示一個(gè)車操縱機(jī)構(gòu)10操縱的被連接到一個(gè)對(duì)易操縱的路輪子12。這個(gè)顯示的操縱機(jī)構(gòu)包括一個(gè)齒條和齒輪匯編14被連接到路輪子12通過聯(lián)接15。 鳥翼末端(沒顯示)匯編14可旋轉(zhuǎn)地駕駛一名手動(dòng)地可旋轉(zhuǎn)的成員以駕駛桿18的形式哪些由方向盤19手動(dòng)地轉(zhuǎn)動(dòng)。這個(gè)駕駛桿18包括包括一臺(tái)電主驅(qū)動(dòng)電動(dòng)機(jī)的一個(gè)電力的傳動(dòng)機(jī)構(gòu)30 (沒顯示在駕駛的鳥翼末端圖1)上以回應(yīng)在駕駛桿18的扭矩裝貨為了為機(jī)械人員提供力量援助，當(dāng)轉(zhuǎn)動(dòng)方向盤19時(shí)。如概要地被說明在表2，電力的傳動(dòng)機(jī)構(gòu)包括測量駕駛桿申請的扭矩18，當(dāng)駕駛鳥翼末端時(shí)并且提供信號(hào)給控制器40的扭矩傳感器20。 控制器40被連接到主驅(qū)動(dòng)電動(dòng)機(jī)50并且控制電流被提供給馬達(dá)50控制馬達(dá)50和它的自轉(zhuǎn)的方向扭矩引起的相當(dāng)數(shù)量。馬達(dá)50 操縱的更適宜地被連接到駕駛桿18通過工具箱60，更適宜地一個(gè)周轉(zhuǎn)齒輪箱子和傳動(dòng)器70。 在一定條件下傳動(dòng)器70在正常運(yùn)行時(shí)更適宜地永久地接合并且是有效的隔絕從馬達(dá)50的驅(qū)動(dòng)使鳥翼末端通過傳動(dòng)機(jī)構(gòu)30手動(dòng)地被駕駛。 這是使機(jī)制的安全特點(diǎn)起作用在試圖的馬達(dá)50情形下駕駛太快速的駕駛桿并且/或者在錯(cuò)誤的方向或在案件 電動(dòng)機(jī)和工具箱占領(lǐng)了。扭矩傳感器20更適宜地是一個(gè)匯編包括在扭矩應(yīng)用達(dá)到的傳感器軸登上應(yīng)變儀能夠準(zhǔn)確測量張力在一個(gè)被預(yù)先決定的范圍之內(nèi)的一個(gè)短的傳感器軸。被測量扭矩的被預(yù)先決定的范圍是0-lONm; 更好是關(guān)于l-5Nm。被測量的扭矩的范圍更好地對(duì)應(yīng)于大約0-1000微指令，并且傳感器軸的建筑更好被選擇這樣5Nm扭矩比在軸的2導(dǎo)致較少的轉(zhuǎn)彎，少于1 。好的應(yīng)變儀是鋸諧振器，在WO91/13832被描述的一臺(tái)適當(dāng)?shù)匿徶C振器。 類似在圖顯示的那WO91/13832 3上更好地運(yùn)用配置，二看見諧振器被安排在對(duì)軸軸的45和在90對(duì)互相。諧振器經(jīng)營與在200-400 MHz之間共鳴頻率和被安排導(dǎo)致信號(hào)到控制器1 MHz 40 500 KHz根據(jù)傳感器軸的自轉(zhuǎn)方向的自我調(diào)節(jié)。 因此，當(dāng)傳感器軸不被扭轉(zhuǎn)的歸結(jié)于缺乏扭矩時(shí)，它導(dǎo)致一個(gè)1 MHz信號(hào)。當(dāng)它導(dǎo)致在1.0到1.5 MHz之間的一個(gè)信號(hào)的傳感器軸在一個(gè)方向被扭轉(zhuǎn)。 當(dāng)傳感器軸在相反方向時(shí)被扭轉(zhuǎn)它導(dǎo)致在1.0到0.5 MHz之間的一個(gè)信號(hào)。 因而同樣傳感器能導(dǎo)致信號(hào)表示程度扭矩并且傳感器軸的自轉(zhuǎn)的方向。好的馬達(dá)扭矩引起的相當(dāng)數(shù)量以回應(yīng)在0-10Nm之間被測量的扭矩是0-40Nm，并且為在l-5Nm之間被測量的扭矩是0-25Nm。反饋電路提供自我調(diào)節(jié)，借以馬達(dá)使用的電流由控制器40測量并且比較保證馬達(dá)在正確方向運(yùn)行并且提供期望功率協(xié)助。 控制器更好地行動(dòng)使被測量的扭矩降低到零和如此控制馬達(dá)增加它的扭矩產(chǎn)品減少被測量的扭矩。 (沒顯示)更適宜地提供車速傳感器哪些寄發(fā)一個(gè)信號(hào)表示車速到控制器。 控制器使用這個(gè)信號(hào)修改程度力量協(xié)助提供以回應(yīng)被測量的扭矩。將提供在低車速最大力量協(xié)助的，因而，并且將提供高車速極小的力量協(xié)助。更適宜地是邏輯順序器有一個(gè)現(xiàn)場可編程序的門數(shù)組例如XC 4005如Xilinx供應(yīng)這個(gè)控制器。 這樣控制器不依靠軟件和，因此能更起作用可靠地在汽車車環(huán)境里。 被想象也許使用有邏輯的序列一個(gè)現(xiàn)場可編程序的列陣。 一個(gè)電力傳動(dòng)機(jī)構(gòu)10的A具體建筑在表3.被說明。電子動(dòng)力轉(zhuǎn)向系統(tǒng)（英文簡稱EPS）， 與液壓動(dòng)力轉(zhuǎn)向系統(tǒng)（HPS）相比，EPS具有很多優(yōu)點(diǎn)。即EPS的優(yōu)勢在于：1）效率高。HPS效率很低，一般為60%70%；而EPS與電機(jī)連接，效率高，有的可高達(dá)90%以上。2）耗能少。汽車在實(shí)際行駛過程中，處于轉(zhuǎn)向的時(shí)間約占行駛時(shí)間的5%，對(duì)于HPS系統(tǒng)，發(fā)動(dòng)機(jī)運(yùn)轉(zhuǎn)時(shí)，油泵始終處于工作狀態(tài)，油液一直在管路中循環(huán)，從而使汽車燃油消耗率增加4%6%；而EPS僅在需要時(shí)供能，使汽車的燃油消耗率僅增加0.5%左右。 3）“路感“好。由于EPS內(nèi)部采用剛性連接，系統(tǒng)的滯后特性可以通過軟件加以控制，且可以根據(jù)駕駛員的操作習(xí)慣進(jìn)行調(diào)整。4）回正性好。EPS結(jié)構(gòu)簡單內(nèi)部阻力小，回正性好，從而可得到最佳的轉(zhuǎn)向回正特性，改善汽車操縱穩(wěn)定性。5）對(duì)環(huán)境污染少。HPS液壓回路中有液壓軟管和接頭，存在油液泄露問題，而且液壓軟管不可回收，對(duì)環(huán)境有有一定污染；而EPS對(duì)環(huán)境幾乎沒有污染。6）可以獨(dú)立于發(fā)動(dòng)機(jī)工作。EPS以電池為動(dòng)力元件，只要電池電量充足，不論發(fā)動(dòng)機(jī)出于何種狀態(tài)，都可以產(chǎn)生助力作用。7）應(yīng)有范圍廣。8）裝配性好易于布置?，F(xiàn)在，動(dòng)力轉(zhuǎn)向系統(tǒng)已成為一些轎車的標(biāo)準(zhǔn)設(shè)置，全世界約有一半的轎車采用動(dòng)力轉(zhuǎn)向。隨著汽車電子技術(shù)的發(fā)展，目前一些轎車已經(jīng)使用電動(dòng)助力轉(zhuǎn)向器，使汽車的經(jīng)濟(jì)性、動(dòng)力性和機(jī)動(dòng)性都有所提高。電動(dòng)助力轉(zhuǎn)向裝置是汽車上一種新的助力轉(zhuǎn)向系統(tǒng)裝置,近年來在國內(nèi)外發(fā)展迅速,由于它采用了可編程電子控制裝置,在帶來靈活性的同時(shí)也存在著安全隱患.在分析這種產(chǎn)品特殊性的基礎(chǔ)上,筆者結(jié)合電子控制裝置的特點(diǎn),指出了事關(guān)安全性的因素,提出了處理安全性的措施,并討論了幾個(gè)事關(guān)安全性的具體問題.研究結(jié)果表明:現(xiàn)有標(biāo)準(zhǔn)不能夠滿足電動(dòng)助力轉(zhuǎn)向裝置安全性的需要;并提出了對(duì)電動(dòng)助力轉(zhuǎn)向裝置進(jìn)行安全性測評(píng)的思想.研究工作對(duì)電動(dòng)助力轉(zhuǎn)向裝置的開發(fā)以及評(píng)價(jià)具有參考意義。英文原文The auto electric power steering system research Along with automobile electronic technology swift and violent development, the people also day by day enhance to the motor turning handling quality request. The motor turning system hanged, the hydraulic pressure boost from the traditional machinery changes (Hydraulic Power Steering, is called HPS), the electrically controlled hydraulic pressure boost changes (Electronic Hydraulic Power Steering, is called EHPS), develops the electrically operated boost steering system (Electronic Power Steering, is called EPS), finally also will transit to the line controls the steering system (Steer By Wire, will be called SBW).The machinery steering system is refers by pilots physical strength achievement changes the energy, in which all power transmission all is mechanical, the automobile changes the movement is operates the steering wheel by the pilot, transmits through the diverter and a series of members changes the wheel to realize. The mechanical steering system by changes the control mechanism, the diverter and major part changes the gearing 3 to be composed.Usually may divide into according to the mechanical diverter form: The gear rack type, follows round the world -like, the worm bearing adjuster hoop type, the worm bearing adjuster refers sells the type. Is the gear rack type and follows using the broadest two kinds round the world -like (uses in needing time big steering force).In follows round the world -like in the diverter, the input changes the circle and the output steering arm pivot angle is proportional; In the gear rack type diverter, the input changes the turn and the output rack displacement is proportional. Follows round the world -like the diverter because is the rolling friction form, thus the transmission efficiency is very high, the ease of operation also the service life are long, moreover bearing capacity, therefore widely applies on the truck. The gear rack type diverter with follows round the world -like compares, the most major characteristic is the rigidity is big, the structure compact weight is light, also the cost is low. Because this way passes on easily by the wheel the reacting force to the steering wheel, therefore has to the pavement behavior response keen merit, but simultaneously also easy to have phenomena and so on goon and oscillation, also its load bearing efficiency relative weak, therefore mainly applies on the compact car and the pickup truck, at present the majority of low end passenger vehicle uses is the gear rack type machinery steering system. Along with the vehicles carrying capacity increase as well as the people to the vehicles handling quality request enhancement, the simple mechanical type steering system were already unable to meet the needs, the power steering system arise at the historic moment, it could rotate the steering wheel while the pilot to provide the boost, the power steering system divides into the hydraulic pressure steering system and the electrically operated steering system 2kinds.Hydraulic pressure steering system is at present uses the most widespread steering system.The hydraulic pressure steering system increased the hydraulic system in the mechanical system foundation, including hydraulic pump, V shape band pulley, drill tubing, feed installment, boost installment and control valve. It with the aid of in the motor car engine power actuation hydraulic pump, the air compressor and the generator and so on, by the fluid strength, the physical strength or the electric power increases the pilot to operate the strength which the front wheel changes, enables the pilot to be possible nimbly to operate motor turning facilely, reduced the labor intensity, enhanced the travel security.The hydraulic pressure boost steering system from invented already had about half century history to the present, might say was one kind of more perfect system, because its work reliable, the technology mature still widely is applied until now. It takes the power supply by the hydraulic pump, after oil pipe-line control valves to power hydraulic cylinder feed, through the connecting rod impetus rotation gear movement, may changes the boost through the change cylinder bore and the flowing tubing head pressure size the size, from this achieved changes the boost the function. The traditional hydraulic pressure type power steering system may divide into generally according to the liquid flow form: Ordinary flow type and atmospheric pressure type 2 kind of types, also may divide into according to the control valve form transfers the valve type and the slide-valve type.Along with hydraulic pressure power steering system on automobile daily popularization, the people to operates when the portability and the road feeling request also day by day enhance, however the hydraulic pressure power steering system has many shortcomings actually: Because its itself structure had decided it is unable to guarantee vehicles rotates the steering wheel when any operating mode, all has the ideal operation stability, namely is unable simultaneously to guarantee time the low speed changes the portability and the high speed time operation stability;The automobile changes the characteristic to drive the pilot technical the influence to be serious; The steering ratio is fixed, causes the motor turning response characteristic along with changes and so on vehicle speed, transverse acceleration to change, the pilot must aim at the motor turning characteristic peak-to-peak value and the phase change ahead of time carries on certain operation compensation, thus controls the automobile according to its wish travel. Like this increased pilots operation burden, also causes in the motor turning travel not to have the security hidden danger; But hereafter appeared the electrically controlled hydraulic booster system, it increases the velocity generator in the traditional hydraulic pressure power steering system foundation, enables the automobile along with the vehicle speed change automatic control force size, has to a certain extent relaxed the traditional hydraulic pressure steering system existence question.At present our country produces on the commercial vehicle and the passenger vehicle uses mostly is the electrically controlled hydraulic pressure boost steering system, it is quite mature and the application widespread steering system. Although the electrically controlled hydraulic servo alleviated the traditional hydraulic pressure from certain degree to change between the portability and the road feeling contradiction, however it did not have fundamentally to solve the HPS system existence insufficiency, along with automobile microelectronic technology development, automobile fuel oil energy conservation request as well as global initiative environmental protection, it in aspect and so on arrangement, installment, leak-proof quality, control sensitivity, energy consumption, attrition and noise insufficiencies already more and more obvious, the steering system turned towards the electrically operated boost steering system development.The electrically operated boost steering system is the present motor turning system development direction, its principle of work is: EPS system ECU after comes from the steering wheel torque sensor and the vehicle speed sensor signal carries on analysis processing, controls the electrical machinery to have the suitable boost torque, assists the pilot to complete changes the operation. In the last few years, along with the electronic technology development, reduces EPS the cost to become large scale possibly, Japan sends the car company, Mitsubishi Car company, this field car company, USs Delphi automobile system company, TRW Corporation and Germanys ZF Corporation greatly all one after another develops EPS.Mercedes2Benz Siemens Automotive Two big companies invested 65,000,000 pounds to use in developing EPS, the goal are together load a car to 2002, yearly produce 300 ten thousand sets, became the global EPS manufacturer. So far, the EPS system in the slight passenger vehicle, on the theater box type vehicle obtains the widespread application, and every year by 300 ten thousand speed development.Steering is the term applied to the collection of components, linkages, etc. which allow for a vessel (ship, boat) or vehicle (car) to follow the desired course. An exception is the case of rail transport by which rail tracks combined together with railroad switches provide the steering function.The most conventional steering arrangement is to turn the front wheels using a handoperated steering wheel which is positioned in front of the driver, via the steering column, which may contain universal joints to allow it to deviate somewhat from a straight line. Other arrangements are sometimes found on different types of vehicles, for example, a tiller or rearwheel steering. Tracked vehicles such as tanks usually employ differential steering that is, the tracks are made to move at different speeds or even in opposite directions to bring about a change of course.Many modern cars use rack and pinion steering mechanisms, where the steering wheel turns the pinion gear; the pinion moves the rack, which is a sort of linear gear which meshes with the pinion, from side to side. This motion applies steering torque to the kingpins of the steered wheels via tie rods and a short lever arm called the steering arm.Older designs often use the recirculating ball mechanism, which is still found on trucks and utility vehicles. This is a variation on the older worm and sector design; the steering column turns a large screw (the worm gear) which meshes with a sector of a gear, causing it to rotate about its axis as the worm gear is turned; an arm attached to the axis of the sector moves the pitman arm, which is connected to the steering linkage and thus steers the wheels. The recirculating ball version of this apparatus reduces the considerable friction by placing large ball bearings between the teeth of the worm and those of the screw; at either end of the apparatus the balls exit from between the two pieces into a channel internal to the box which connects them with the other end of the apparatus, thus they are recirculated.The rack and pinion design has the advantages of a large degree of feedback and direct steering feel; it also does not normally have any backlash, or slack. A disadvantage is that it is not adjustable, so that when it does wear and develop lash, the only cure is replacement.The recirculating ball mechanism has the advantage of a much greater mechanical advantage, so that it was found on larger, heavier vehicles while the rack and pinion was originally limited to smaller and lighter ones; due to the almost universal adoption of power steering, however, this is no longer an important advantage, leading to the increasing use of rack and pinion on newer cars. The recirculating ball design also has a perceptible lash, or dead spot on center, where a minute turn of the steering wheel in either direction does not move the steering apparatus; this is easily adjustable via a screw on the end of the steering box to account for wear, but it cannot be entirely eliminated or the mechanism begins to wear very rapidly. This design is still in use in trucks and other large vehicles, where rapidity of steering and direct feel are less important than robustness, maintainability, and mechanical advantage. The much smaller degree of feedback with this design can also sometimes be an advantage; drivers of vehicles with rack and pinion steering can have their thumbs broken when a front wheel hits a bump, causing the steering wheel to kick to one side suddenly (leading to driving instructors telling students to keep their thumbs on the front of the steering wheel, rather than wrapping around the inside of the rim). This effect is even stronger with a heavy vehicle like a truck; recirculating ball steering prevents this degree of feedback, just as it prevents desirable feedback under normal circumstances.The steering linkage connecting the steering box and the wheels usually conforms to a variation of Ackermann steering geometry, to account for the fact that in a turn, the inner wheel is actually traveling a path of smaller radius than the outer wheel, so that the degree of toe suitable for driving in a straight path is not suitable for turns.As vehicles have become heavier and switched to front wheel drive, the effort to turn the steering wheel manually has increased - often to the point where major physical exertion is required. To alleviate this, auto makers have developed power steering systems. There are two types of power steering systemshydraulic and electric/electronic. There is also a hydraulic-electric hybrid system possible.A hydraulic power steering (HPS) uses hydraulic pressure supplied by an engine-driven pump to assist the motion of turning the steering wheel. Electric power steering (EPS) is more efficient than the hydraulic power steering, since the electric power steering motor only needs to provide assist when the steering wheel is turned, whereas the hydraulic pump must run constantly. In EPS the assist level is easily tunable to the vehicle type, road speed, and even driver preference. An added benefit is the elimination of environmental hazard posed by leakage and disposal of hydraulic power steering fluid.An outgrowth of power steering is speed adjustable steering, where the steering is heavily assisted at low speed and lightly assisted at high speed. The auto makers perceive that motorists might need to make large steering inputs while manoeuvering for parking, but not while traveling at high speed. The first vehicle with this feature was the Citron SM with its Diravi layout, although rather than altering the amount of assistance as in modern power steering systems, it altered the pressure on a centring cam which made the steering wheel try to spring back to the straight-ahead position. Modern speed-adjustable power steering systems reduce the pressure fed to the ram as the speed increases, giving a more direct feel. This feature is gradually becoming commonplace across all new vehicles.Four-wheel steering (or all wheel steering) is a system employed by some vehicles to increase vehicle stability while maneuvering at high speed, or to decrease turning radius at low speed.In most four-wheel steering systems, the rear wheels are steered by a computer and actuators. The rear wheels generally cannot turn as far as the Alternatively, several systems, including Delphis Quadrasteer and the system in Hondas Prelude line, allow for the rear wheels to be steered in the opposite direction as the front wheels during low speeds. This allows the vehicle to turn in a significantly smaller radius sometimes critical for large trucks or vehicles with trailers. An exception is the case of rail transport by which rail tracks combined together with railroad switches provide the steering function.Many modern cars use steering mechanisms, where the steering wheel turns the pinion gear; the pinion moves the rack, which is a sort of linear gear which meshes with the pinion, from side to side.mechanism, which is still found on trucks and utility vehicles.This is a variation on the older and thus steers the wheels.The recirculating ball version of this apparatus reduces the considerable friction by placing large ball bearings between the teeth of the worm and those of the screw; at either end of the apparatus the balls exit from between the two pieces into a channel internal to the box which connects them with the other end of the apparatus, thus they are recirThe rack and pinion design has the advantages of a large degree of feedback and direct steering feel; it also does not normally have any , or slack.culated.A disadvantage is that it is not adjustable, so that when it does wear and develop lash, the only cure is replacement.The recirculating ball mechanism has the advantage of a much greater , however, this is no longer an important advantage, leading to the increasing use of rack and pinion on newer cars.to account for wear, but it cannot be entirely eliminated or the mechanism begins to wear very rapidly.This design is still in use in trucks and other large vehicles, where rapidity of steering and direct feel are less important than robustness, maintainability, and mechanical advantage.The much smaller degree of feedback with this design can also sometimes be an advantage; drivers of vehicles with rack and pinion steering can have their thumbs broken when a front wheel hits a bump, causing the steering wheel to kick to one side suddenly (leading to driving instructors telling students to keep their thumbs on the front of the steering wheel, rather than wrapping around the inside of the rim). This effect is even stronger with a heavy vehicle like a truck; recirculating ball steering prevents this degree of feedback, just as it prevents desirable feedback under normal circumstances.As vehicles have become heavier and switched to front wheel drive , the effort to turn the steering wheel manually has increased - often to the point where major physical exertion is required.There are two types of power steering systemshydraulic and electric/electronic.here is also a hydraulic-electric hybrid system possible.A hydraulic power steering (HPS) uses hydraulic pressure supplied by an engine-driven pump to assist the motion of turning the stElectric power steering (EPS) is more efficient than the hydraulic power steering, since the electric power steering motor only needs to provide assist when the steering wheel is turned, whereas the hydraulic pump must run constantly.eering wheel.In EPS the assist level is easily tunable to the vehicle type, road speed, and even driver preference.An added benefit is the elimination of environmental hazard posed by leakage and disposal of hydraulic power steering fluid.n outgrowth of power steering is speed adjustable steering, where the steering is heavily assisted at low speed and lightly assisted at high speed.The auto makers perceive that motorists might need to make large steering inputs while manoeuvering for parking, but not while traveling at high speed.The first vehicle with this feature was the Citron SM with its Diravi layout, although rather than altering the amount of assistance as in modern power steering systems, it altered the pressure on a centring cam which made the steering wheel try to spring back to the straight-ahead position.Modern speed-adjustable power steering systems reduce the pressure fed to the ram as the speed increases, The rear wheels giving a more direct feel.This feature is gradually becoming commonplace across all new vehicles.In most four-wheel steering systems, the rear wheels are steered by a computer and actuators.generally cannot turn as far as the Alternatively, several systems, including Delphis Quadrasteer and the system in Hondas Prelude line, allow for the rear wheels to be steered in the opposite direction as the front wheels during low speeds.This allows the vehicle to turn in a significantly smaller radius sometimes critical for large trucks or vehicles with trailers.Electronic power steering system What it isElectrically powered steering uses an electric motor to drive either the power steering hydraulic pump or the steering linkage directly. The power steering function is therefore independent of engine speed, resulting in significant energy savings.How it works :Conventional power steering systems use an engine accessory belt to drive the pump, providing pressurized fluid that operates a piston in the power steering gear or actuator to assist the driver.In electro-hydraulic steering, one electrically powered steering concept uses a high efficiency