KD1060型貨車設(shè)計（轉(zhuǎn)向及前橋設(shè)計）【3張CAD圖紙+外文翻譯+畢業(yè)論文】
38頁 10824字數(shù)+論文說明書【詳情如下】
KD1060型貨車設(shè)計（轉(zhuǎn)向及前橋設(shè)計）論文.doc
前橋總裝配圖.dwg
外文翻譯--轉(zhuǎn)向系統(tǒng).docx
轉(zhuǎn)向器裝配圖.dwg
轉(zhuǎn)向系總成.dwg
KD1060型貨車設(shè)計（轉(zhuǎn)向及前橋設(shè)計）
摘 要
汽車在行駛過程中，需要經(jīng)常改變行駛方向，這就需要有一套能夠按照司機意志來改變或恢復汽車行駛方向的專設(shè)機構(gòu)，它將司機轉(zhuǎn)動方向盤的動作轉(zhuǎn)變?yōu)檐囕喌钠D(zhuǎn)動作，這就是所謂的轉(zhuǎn)向系統(tǒng)。轉(zhuǎn)向性能是保證車輛安全，減輕駕駛員勞動強度和提高作業(yè)效率的重要因素。由于轉(zhuǎn)向系統(tǒng)是汽車的重要組成部分，它直接與汽車的行駛穩(wěn)定性有重要的關(guān)系，與前懸架和車輪關(guān)系亦十分密切，故轉(zhuǎn)向系統(tǒng)的設(shè)計也是整車設(shè)計中的關(guān)鍵一環(huán)。本設(shè)計為KD1060型載貨汽車的轉(zhuǎn)向系統(tǒng)設(shè)計，轉(zhuǎn)向系統(tǒng)設(shè)計內(nèi)容主要包括轉(zhuǎn)向系統(tǒng)形式的選擇、轉(zhuǎn)向器的選擇、轉(zhuǎn)向梯形的選擇及其布置。
在本次設(shè)計中采用了機械式轉(zhuǎn)向系統(tǒng)，機械式轉(zhuǎn)向系統(tǒng)的特點是重量輕,結(jié)構(gòu)緊湊,布置方便,維修容易,操縱輕便,穩(wěn)定性好,成本低廉，不易出現(xiàn)直線行駛時的蛇形現(xiàn)象。機械式轉(zhuǎn)向系統(tǒng)還具有維修方便，容易安裝調(diào)整的優(yōu)點。轉(zhuǎn)向系統(tǒng)的轉(zhuǎn)向器選用的是整體式循環(huán)球轉(zhuǎn)向器, 整體式循環(huán)球轉(zhuǎn)向器的特點是可以將傳遞力矩機構(gòu)之間的滑動摩擦轉(zhuǎn)變?yōu)闈L動摩擦,這就使得轉(zhuǎn)向傳動效率提高,使用壽命增長,傳動比可以改變,轉(zhuǎn)向工作平穩(wěn)可靠。轉(zhuǎn)向傳動機構(gòu)選用整體式梯形,這樣有利于保證KD1060型汽車在車輪轉(zhuǎn)動時作無滑動的純滾動運動,并且機構(gòu)簡單, 容易調(diào)整前輪前束。
在說明書的計算部分，對轉(zhuǎn)向器和轉(zhuǎn)向梯形主要參數(shù)選擇進行了計算。此外，還校核了主要零件的強度。
關(guān)鍵詞：轉(zhuǎn)向系統(tǒng),機械轉(zhuǎn)向,前橋,轉(zhuǎn)向器
KD1060 GOODS VEHICLE DESIGN
(STEERING SYSTEM AND THE FRONT AXLE)
ABSTRACT
The automobiles often need to change the direction in driving, then a particular set of device which can change or recover the automobile’s running route according to the driver’s will is needed.
The device changing the action that the driver turns to move the steering wheel to the action of deflection of carriage wheels is called as steering system. The function of changing direction is to guarantee the vehicle’s safety, relieve the intension of labor and raise working efficiency. The steering system is important component of an automobile. It plays an important role on the driving stability of the automobile. And it also has close relationship with the front suspension and wheel tire components, so the design of the steering system is a key link in designing automobile.
The aim of this project is to design the steering system for KD1060 goods vehicle. The main job of designing steering system includes determining the kind of steering system, steering gear and the steering trapezoid and figure out how to fix them.
Manual steering system is adopted in this project. Manual steering system’s features are: weight light, tightly packed structure, convenient arrangements, easy manipulation, stabile quality, low cost. And the s form phenomenon seldom emerges in straightaway traveling.
It has other advantages: convenient maintenance. Integral circulating ball steering gears is working as steering gear in this design of medium freight steering system. Integral circulating ball steering gears can change slide friction between devices of carry-over momentums into rolling friction. This feature is propitious to better transfer motion efficiency; prolong application life, change transmission ratio and better degree of reliability of steering. Integrality trapezoid is adopted as Steering drive linkage, to guarantee automobile’s front wheel exercise of pure rolling without sliding. The structure is simple. And it is easy to adjust the toe-in.
The calculation section of this paper is mainly concerning about steering trapezoid and steering gear .In addition, the life of the main components are also calculated in this section.
KEY WORDS: The steering system, Manual steering, Front axle, Steering device
目錄
前言...........................................1
第一章概述.....................................2
第二章從動橋的方案確定.........................4
第三章轉(zhuǎn)向系的方案確定..........................6
§3.1 轉(zhuǎn)向系整體方案確定........................6
§3.2 轉(zhuǎn)向系結(jié)構(gòu)形式及選擇......................6
§3.3 循環(huán)球式轉(zhuǎn)向器結(jié)構(gòu)及選擇..................7
第四章從動橋的設(shè)計計算.........................8
§4.1從動橋主要零件尺寸的確定..................8
§4.2 從動橋主要零件工作應力的計算..............8
§4.3 在最大側(cè)向力(側(cè)滑)工況下的前梁應力計算...10
§4.4 轉(zhuǎn)向節(jié)在制動和側(cè)滑工況下的應力計算.......11
§4.5 主銷與轉(zhuǎn)向節(jié)襯套在制動和側(cè)滑工況下的應力.13
§4.6轉(zhuǎn)向節(jié)推力軸承的計算...............15
第五章轉(zhuǎn)向系統(tǒng)的設(shè)計計算................17
§5.1 轉(zhuǎn)向系主要性能參數(shù)..................17
§5.2 主要參數(shù)的確定......................18
§5.3 轉(zhuǎn)向梯形的選擇設(shè)計.....................20
§5.4 循環(huán)球式轉(zhuǎn)向器的設(shè)計..................21
§5.5 轉(zhuǎn)向系主要性能參數(shù)確定..................24
§5.6 轉(zhuǎn)向系其他元件的選擇及材料的確定.........25
第六章轉(zhuǎn)向系主要零件的強度計算..............26
§6.1 計算載荷的確定.......................26
§6.2 主要零件的強度計算..................26
第七章 結(jié)論...........................28
參考文獻...........................29
致謝..........................................30
前言
在目前金融危機的大環(huán)境下，伴隨著汽車行業(yè)的發(fā)展，輕型貨運汽車在國民生產(chǎn)中扮演著更重要的角色。
輕型載貨汽車各個領(lǐng)域得到了廣泛應用，對于它的設(shè)計是依據(jù)以往理論知識及實踐經(jīng)驗，在滿足其功用的前提下來進行的。轉(zhuǎn)向系統(tǒng)是用來保持或改變汽車行駛方向的機構(gòu)，它在整體設(shè)計中亦有其重要地位，對轉(zhuǎn)向時車輪正確運動和汽車的安全行駛有重大影響，這就要求其工作可靠、操縱輕便。
在目前的設(shè)計和使用方面，轉(zhuǎn)向系統(tǒng)由機械式和動力式兩類，由于動力式轉(zhuǎn)向系統(tǒng)能減輕駕駛員的負擔，而且操作方便，所以到廣泛使用。機械式轉(zhuǎn)向系統(tǒng)由于造價低廉，而且能夠滿足輕型貨車等一大部分汽車的轉(zhuǎn)向需要，固也得到了廣泛的使用。機械式轉(zhuǎn)向系由操縱機構(gòu)、轉(zhuǎn)向器和轉(zhuǎn)向傳動機構(gòu)組成，其重點是轉(zhuǎn)向器和傳動機構(gòu)的設(shè)計?，F(xiàn)今國內(nèi)輕型汽車多才用整體式循環(huán)球式轉(zhuǎn)向器，整體式后置梯形。
本畢業(yè)設(shè)計說明書，主要講述了前橋和轉(zhuǎn)向系統(tǒng)的選擇設(shè)計和方案分析。對前橋和轉(zhuǎn)向系統(tǒng)的分類和工作原理進行了深入的對比和分析，選出最優(yōu)方案來進行設(shè)計；對于轉(zhuǎn)向系統(tǒng)的重要組成部分轉(zhuǎn)向器和轉(zhuǎn)向傳動機構(gòu)進行分析設(shè)計，選擇合適的機構(gòu)和零件。
第一章 概述
從動橋通過懸架與車架相聯(lián)，兩側(cè)安裝著從動車輪，用以在車架與車輪之間傳遞鉛垂力、縱向力和橫向力。從動橋還要承受和傳遞制動力矩。
根據(jù)從動車輪能否轉(zhuǎn)向，從動橋分為轉(zhuǎn)向橋與非轉(zhuǎn)向橋。一般汽車多以前橋為轉(zhuǎn)向橋。為提高操縱穩(wěn)定性和機動性，有些轎車采用全四輪轉(zhuǎn)向。多軸汽車除前輪轉(zhuǎn)向外，根據(jù)對機動性的要求，有時采用兩根以上的轉(zhuǎn)向橋直至全輪轉(zhuǎn)向。
一般載貨汽車采用前置發(fā)動機后橋驅(qū)動的布置形式，故其前橋為轉(zhuǎn)向從動橋。轎車多采用前置發(fā)動機前橋驅(qū)動，越野汽車均為全輪驅(qū)動，故它們的前橋既是轉(zhuǎn)向橋又是驅(qū)動橋，稱為轉(zhuǎn)向驅(qū)動橋。
從動橋按與其匹配的懸架結(jié)構(gòu)的不同，也可分為非斷開式與斷開式兩種。與非獨立懸架相匹配的非斷開式從動橋是一根支承于左、右從動車輪上的剛性整體橫梁，當又是轉(zhuǎn)向橋時，則其兩端經(jīng)轉(zhuǎn)向主銷與轉(zhuǎn)向節(jié)相聯(lián)。斷開式從動橋與獨立懸架相匹配。
為了保持汽車直線行駛的穩(wěn)定性、轉(zhuǎn)向輕便性及汽車轉(zhuǎn)向后使前輪具有自動回正的性能，轉(zhuǎn)向橋的主銷在汽車的縱向和橫向平而內(nèi)都有一定傾角。在縱向平面內(nèi)，主銷上部向后傾斜一個角，稱為主銷后傾角。在橫向平面內(nèi)，主銷上部向內(nèi)傾斜一個β角，稱為主銷內(nèi)傾角。還有車輪外傾角及前束。
在汽車的設(shè)計、制造、裝配調(diào)整和使用中必須注意防止可能引起的轉(zhuǎn)向車輪的擺振，它是指汽車行駛時轉(zhuǎn)向輪繞主銷不斷擺動的現(xiàn)象，它將破壞汽車的正常行駛。轉(zhuǎn)向車輪的擺振有自激振動與受迫振動兩種類型。前者是由于輪胎側(cè)向變形中的遲滯特性的影響，使系統(tǒng)在一個振動周期中路面作用于輪胎的力對系統(tǒng)作正功，即外界對系統(tǒng)輸入能量。如果后者的值大于系統(tǒng)內(nèi)阻尼消耗的能量，則系統(tǒng)將作增幅振動直至能量達到動平衡狀態(tài)。這時系統(tǒng)將在某一振幅下持續(xù)振動，形成擺振。其振動頻率大致接近系統(tǒng)的固有頻率而與車輪轉(zhuǎn)速并不一致，且會在較寬的車速范圍內(nèi)發(fā)生。通常在低速行駛時發(fā)生的擺振往往屬于自攝振動型。當轉(zhuǎn)向車輪及轉(zhuǎn)向系統(tǒng)受到周期性擾動的激勵，例如車輪失衡、端面跳動、輪胎的幾何和機械特性不均勻以及運動學上的干涉等，在車輪轉(zhuǎn)動下都會構(gòu)成周期性的擾動。在擾動力周期性的持續(xù)作用下，便會發(fā)生受迫振動。當擾動的激勵頻率與系統(tǒng)的固有頻率一致時便發(fā)生共振。其特點是轉(zhuǎn)向輪擺振頻率與車輪轉(zhuǎn)速一致，而且一般都有明顯的共振車速，共振范圍較窄(3～5km/h)。通常在高速行駛時發(fā)生的擺振往往屬于受迫振動型。
轉(zhuǎn)向輪擺振的發(fā)生原因及影響因素復雜，既有結(jié)構(gòu)設(shè)計的原因和制造方面的因素．如車輪失衡、輪胎的機械特性、系統(tǒng)的剛度與阻尼、轉(zhuǎn)向輪的定位角以及陀螺效應的強弱等；又有裝配調(diào)整方面的影響，如前橋轉(zhuǎn)向系統(tǒng)各個環(huán)節(jié)間的間隙(影響系統(tǒng)的剛度)和摩擦系數(shù)(影響阻尼)等。合理地選擇這些有關(guān)參數(shù)、優(yōu)化它們之間的匹配，精心地制造和裝配調(diào)整，就能有效地控制前輪擺振的發(fā)生。在設(shè)計中提高轉(zhuǎn)向器總成與轉(zhuǎn)向拉桿系統(tǒng)的剛度及懸架的縱向剛度，提高輪胎的側(cè)向剛度，在轉(zhuǎn)向拉桿系中設(shè)置橫向減震器以增加阻尼等，都是控制前輪擺振發(fā)生的一些有效措施。第七章 結(jié)論
通過對前橋及轉(zhuǎn)向的設(shè)計，我得出結(jié)論，此設(shè)計滿足設(shè)計要求。第二章列出了前橋的設(shè)計方案，第三章列出了轉(zhuǎn)向系的設(shè)計方案，第四章主要對前橋的主要零件進行了強度校核，經(jīng)校核滿足要求。第五章主要對轉(zhuǎn)向系的方案進行了論證，并詳細計算了循環(huán)球式轉(zhuǎn)向器的各個參數(shù)，這說明也是可行的。故此設(shè)計我比較滿意，真誠接受各評委老師的批評指教！
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致 謝
畢業(yè)設(shè)計的完成首先要感謝老師，老師在繁忙的工作中為我們的畢業(yè)設(shè)計提供了大量資料，并在設(shè)計過程中對我們進行了耐心的開導，給我們提了好多中肯的建議和方法。再次對老師表示衷心的感謝！
其次感謝做畢業(yè)設(shè)計的各位同學，他們可謂是我的良師益友，許多問題我們在互相探討中共同成長，三人行，必有我?guī)?，每個人都有自己的長處和優(yōu)點。還有本系的領(lǐng)導，系辦，車輛研究所，車輛實驗室老師的關(guān)心和支持！在此一并表示感謝！
外文資料及翻譯Steering systemMotor steering system: On the automobile uses for to change or restores its travel direction to suppose the organization to be called the motor turning system specially. Automobile's steering system is uses for to change the automobile travel direction and to maintain the automobile straight line travel organization Composes (1)To change the control mechanism basically mainly by the steering wheel, the steering axle, the steering tube column and so on to be composed. (2) Diverter becomes steering wheel's rotation steering arm's swinging or the rack axis straight reciprocating motion, and to changes the control force to carry on the enlargement the organization. The diverter fixes generally on the automobile frame or the automobile body, changes the control force after the diverter generally will also change the transmission direction. (3) Steering transmission system the strength which and the movement outputs the diverter passes to the wheel (knuckle), about and causes the wheel to carry on the deflection according to certain relations the organization.Type Crooked to energy difference, the steering system may divide into the machinery steering system and the power steering system two broad headings crooked. Mechanical steering system: And changes the transmission system by the diverter to be composed. Diverter: By the steering wheel, the steering wheel steering axle, changes meshing to pay (diverter) to be composed. Steering transmission system: By drop arm (drop arm), drag link, drag link arm, about trapezoidal arm, steering knuckle tie rod, if a dry bulb joint composes.Power steering system: Changes the augmenter constitution by mechanical steering system Canada.1.Mechanical steering system The mechanical steering system changes the energy by pilot's physical strength achievement, all power transmission are the machinery. The mechanical steering system by changes the control mechanism, the diverter and changes the transmission system three major part to be composed.(1) steering control mechanismChanges the control mechanism by the steering wheel, the steering axle, the steering tube column and so on to be composed, its function is rotates the pilot steering wheel's control force to pass to the divertor.(2) Divertor The diverter (also often is called steering unit) is completes from the rotary motion to the translation (or approximate straightline motion) a group of gear mechanism, simultaneously is also in the steering system speed reducer drive. At present the commonly used toothed wheel rack type, follows round the world the crank to refer to sells the type, the worm bearing adjuster crank to refer to sells the type, to follow round the world - the tooth rack tooth fan type, the worm bearing adjuster hoop type and so on. We mainly introduce the first several kinds.1) Gear rack type divertorThe gear rack type diverter divides the both sides output type and among (or single end) the output type two kinds .The both sides output's gear rack type diverter, changes the gear shaft as the transmission vice-host moving parts and installs through the bearing in the diverter shell, its upper extreme through spline and universal joint sliding yoke and steering axle connection. With the steering gear meshing steering rack level arrangement, the both sides with change the steering knuckle tie rod through a ball place to be connected. The spring presses through the briquetting the rack depending in the gear, guarantees ceaseless meshing.Spring's pretightening up force available adjustment thread plug adjustment. When rotates the steering wheel, the diverter gear-driven, causes with it meshing rack along the end motion, thus about causes the steering knuckle tie rod to lead about the knuckle to rotate, causes to change the wheel deflection, thus realizes motor turning.Middle output gear rack type diverter, its structure and principle of work and both sides output gear rack type diverter basic same, the difference lies in it to change the steering knuckle tie rod in steering rack's middle with the bolt with about to be connected. On single-ended output's gear rack type diverter, a rack's end with changes the steering knuckle tie rod through the inside and outside bracket to be connected.2) Follows round the world-like the divertorFollows round the world-like the diverter is one of present domestic and foreign application most widespread structure patterns, generally has two-stage drive, the first level is screw rod nut transmission, the second level is tooth rack tooth fan transmission.In order to reduce between the steering screw steering nut's friction, the two's thread immediate contact, during is loaded with many steel balls, realizes the rolling friction. On the steering screw and the nut processes the profiled outline is two section or three section of not concentric circular arc composition approximate semicircle spiral groove. The two's spiral groove can coordinate to form the approximate circular cross section the spiral tubular channel.The nut side has two pair of through holes, may henceforth the vent plug enter the steel ball in the helix channel. Outside the steering nut has two steel ball drive pipes, each drive pipe's both sides insert the nut side separately in a pair of through hole. In the drive pipe has also packed the steel ball. Thus, in two drive pipes and nut's spiral tubular channels combine two respectively independent seals the steel ball " the flow channel ".When the steering screw rotates, passes to the steering nut through the steel ball the strength, the nut namely along the end motion. At the same time, friction couple function between the screw rod and the nut and under the steel ball, all steel balls then rolls in the spiral tubular channel, formation " ball class ". When the diverter works, two rows steel balls are only in the respective seal flow channel internal recycling, will leave.3) The worm bearing adjuster crank refers to sells the type diverterThe worm bearing adjuster crank refers to sells the type diverter's transmissionvice-(by the steering worm primarily moving parts, it is installs from the moving parts in the rocker arm shaft crank nose refers to sells. When the steering worm rotates, refers to with it meshing sells namely circles the rocker arm shaft spool thread along the circular, and leads the rocker arm shaft rotation.(3) Steering transmission systemSteering transmission system the function is the strength which and the movement outputs the diverter passes to the steering axle both sides the knuckle, causes the both sides wheering wheel deflection, and causes two wheering wheel deflection angles according to certain relational change, guarantees when motor turning the wheel and the ground relative sliding is as far as possible small.1) Uses for parts with the non-independent suspension fork changes the transmission system mainly to include the steering arm, to change the drag link, the steering, and the steering trapezium. In the front axle is only in the steering axle situation, by changes the steering trapezium general arrangement which the steering knuckle tie rod and the left and right trapezoidal arm are composed after the front axle, when the wheering wheel is in with the automobile straight line travel corresponding neutral point, trapezoidal arm and steering knuckle tie rod in and path parallel plane (horizontal plane) in angle of intersection >90.In the engine position is low or in the steering axle concurrently sufficient driving axle's situation, to avoid the movement interference, often steering trapezium arrangement before the front axle, this time above angle of intersection <90, if the steering arm is not around swings in the automobile fore-and-aft plane, but is shaking right toward left with the path parallel plane, then may change the drag link horizontal, and sells taking advantage of ball leads directly changes the steering knuckle tie rod, thus pushes somebody into doing something the both sides trapezoidal arm rotation.2) Uses for parts with the independent suspension fork changes the transmission systemWhen wheering wheel independent suspension, each wheering wheel needs to be opposite in the frame makes the independence movement, thus the steering axle must be the separation type. With this corresponding, changes in the transmission system the steering trapezium also to be the separation type.3) Steering drag link.Changes drag link's function is the strength which and the movement transmits the steering arm passes to the steering trapezium arm (or steering). It receives the strength already has the pulling force, also to have the pressure, therefore the drag link is uses the high quality special steel products manufacture, guarantees the operation reliable. In wheering wheel deflection or because of suspension fork elastic deformation when is opposite beats in the frame, changes the drag link and the steering arm and the steering relative motion is the space motion, for does not have the movement interference, the above three connection uses the pin ball. 轉(zhuǎn)向系統(tǒng)汽車轉(zhuǎn)向系統(tǒng)：汽車上用來改變或恢復其行駛方向的專設(shè)機構(gòu)稱為汽車轉(zhuǎn)向系統(tǒng)。汽車的轉(zhuǎn)向系統(tǒng)是用來改變汽車行駛方向和保持汽車直線行駛的機構(gòu)基本組成(1)轉(zhuǎn)向操縱機構(gòu)主要由轉(zhuǎn)向盤、轉(zhuǎn)向軸、轉(zhuǎn)向管柱等組成。(2)轉(zhuǎn)向器將轉(zhuǎn)向盤的轉(zhuǎn)動變?yōu)檗D(zhuǎn)向搖臂的擺動或齒條軸的直線往復運動，并對轉(zhuǎn)向操縱力進行放大的機構(gòu)。轉(zhuǎn)向器一般固定在汽車車架或車身上，轉(zhuǎn)向操縱力通過轉(zhuǎn)向器后一般還會改變傳動方向。(3)轉(zhuǎn)向傳動機構(gòu)將轉(zhuǎn)向器輸出的力和運動傳給車輪(轉(zhuǎn)向節(jié))，并使左右車輪按一定關(guān)系進行偏轉(zhuǎn)的機構(gòu)。類型按轉(zhuǎn)向能源的不同，轉(zhuǎn)向系統(tǒng)可分為機械轉(zhuǎn)向系統(tǒng)和動力轉(zhuǎn)向系統(tǒng)兩大類。機械轉(zhuǎn)向系：由轉(zhuǎn)向器和轉(zhuǎn)向傳動機構(gòu)組成.轉(zhuǎn)向器：由方向盤，方向盤轉(zhuǎn)向軸，轉(zhuǎn)向嚙合付(轉(zhuǎn)向器)組成.轉(zhuǎn)向傳動機構(gòu)：由轉(zhuǎn)向臂(轉(zhuǎn)向垂臂)，直拉桿，直拉桿臂，左右梯形臂，橫拉桿，若干球頭關(guān)節(jié)組成.動力轉(zhuǎn)向系：由機械轉(zhuǎn)向系加轉(zhuǎn)向加力裝置構(gòu)成.1．機械轉(zhuǎn)向系機械轉(zhuǎn)向系以駕駛員的體力作為轉(zhuǎn)向能源，其中所有傳力件都是機械的。機械轉(zhuǎn)向系由轉(zhuǎn)向操縱機構(gòu)、轉(zhuǎn)向器和轉(zhuǎn)向傳動機構(gòu)三大部分組成。（1）轉(zhuǎn)向操縱機構(gòu)轉(zhuǎn)向操縱機構(gòu)由方向盤、轉(zhuǎn)向軸、轉(zhuǎn)向管柱等組成，它的作用是將駕駛員轉(zhuǎn)動轉(zhuǎn)向盤的操縱力傳給轉(zhuǎn)向器。（2 ）轉(zhuǎn)向器轉(zhuǎn)向器(也常稱為轉(zhuǎn)向機)是完成由旋轉(zhuǎn)運動到直線運動(或近似直線運動)的一組齒輪機構(gòu)，同時也是轉(zhuǎn)向系中的減速傳動裝置。 目前較常用的有齒輪齒條式、循環(huán)球曲柄指銷式、蝸桿曲柄指銷式、循環(huán)球-齒條齒扇式、蝸桿滾輪式等。我們主要介紹前幾種。1）齒輪齒條式轉(zhuǎn)向器齒輪齒條式轉(zhuǎn)向器分兩端輸出式和中間（或單端）輸出式兩種。兩端輸出的齒輪齒條式轉(zhuǎn)向器，作為傳動副主動件的轉(zhuǎn)向齒輪軸通過軸承和安裝在轉(zhuǎn)向器殼體中，其上端通過花鍵與萬向節(jié)叉和轉(zhuǎn)向軸連接。與轉(zhuǎn)向齒輪嚙合的轉(zhuǎn)向齒條水平布置，兩端通過球頭座與轉(zhuǎn)向橫拉桿相連。彈簧通過壓塊將齒條壓靠在齒輪上，保證無間隙嚙合。彈簧的預緊力可用調(diào)整螺塞調(diào)整。當轉(zhuǎn)動轉(zhuǎn)向盤時，轉(zhuǎn)向器齒輪轉(zhuǎn)動，使與之嚙合的齒條沿軸向移動，從而使左右橫拉桿帶動轉(zhuǎn)向節(jié)左右轉(zhuǎn)動，使轉(zhuǎn)向車輪偏轉(zhuǎn)，從而實現(xiàn)汽車轉(zhuǎn)向。 中間輸出的齒輪齒條式轉(zhuǎn)向器，其結(jié)構(gòu)及工作原理與兩端輸出的齒輪齒條式轉(zhuǎn)向器基本相同，不同之處在于它在轉(zhuǎn)向齒條的中部用螺栓與左右轉(zhuǎn)向橫拉桿相連。在單端輸出的齒輪齒條式轉(zhuǎn)向器上，齒條的一端通過內(nèi)外托架與轉(zhuǎn)向橫拉桿相連。2）循環(huán)球式轉(zhuǎn)向器循環(huán)球式轉(zhuǎn)向器是目前國內(nèi)外應用最廣泛的結(jié)構(gòu)型式之一， 一般有兩級傳動副，第一級是螺桿螺母傳動副，第二級是齒條齒扇傳動副。為了減少轉(zhuǎn)向螺桿轉(zhuǎn)向螺母之間的摩擦，二者的螺紋并不直接接觸，其間裝有多個鋼球，以實現(xiàn)滾動摩擦。轉(zhuǎn)向螺桿和螺母上都加工出斷面輪廓為兩段或三段不同心圓弧組成的近似半圓的螺旋槽。二者的螺旋槽能配合形成近似圓形斷面的螺旋管狀通道。螺母側(cè)面有兩對通孔，可將鋼球從此孔塞入螺旋形通道內(nèi)。轉(zhuǎn)向螺母外有兩根鋼球?qū)Ч?，每根導管的兩端分別插入螺母側(cè)面的一對通孔中。導管內(nèi)也裝滿了鋼球。這樣，兩根導管和螺母內(nèi)的螺旋管狀通道組合成兩條各自獨立的封閉的鋼球"流道 "。轉(zhuǎn)向螺桿轉(zhuǎn)動時，通過鋼球?qū)⒘鹘o轉(zhuǎn)向螺母，螺母即沿軸向移動。同時，在螺桿及螺母與鋼球間的摩擦力偶作用下，所有鋼球便在螺旋管狀通道內(nèi)滾動，形成" 球流 "。在轉(zhuǎn)向器工作時，兩列鋼球只是在各自的封閉流道內(nèi)循環(huán)，不會脫出。3）蝸桿曲柄指銷式轉(zhuǎn)向器蝸桿曲柄指銷式轉(zhuǎn)向器的傳動副(以轉(zhuǎn)向蝸桿為主動件，其從動件是裝在搖臂軸曲柄端部的指銷。轉(zhuǎn)向蝸桿轉(zhuǎn)動時，與之嚙合的指銷即繞搖臂軸軸線沿圓弧運動，并帶動搖臂軸轉(zhuǎn)動。（3）轉(zhuǎn)向傳動機構(gòu)轉(zhuǎn)向傳動機構(gòu)的功用是將轉(zhuǎn)向器輸出的力和運動傳到轉(zhuǎn)向橋兩側(cè)的轉(zhuǎn)向節(jié)，使兩側(cè)轉(zhuǎn)向輪偏轉(zhuǎn)，且使二轉(zhuǎn)向輪偏轉(zhuǎn)角按一定關(guān)系變化，以保證汽車轉(zhuǎn)向時車輪與地面的相對滑動盡可能小。1）與非獨立懸架配用的轉(zhuǎn)向傳動機構(gòu)與非獨立懸架配用的轉(zhuǎn)向傳動機構(gòu)主要包括轉(zhuǎn)向搖臂、轉(zhuǎn)向直拉桿、轉(zhuǎn)向節(jié)臂、和轉(zhuǎn)向梯形。在前橋僅為轉(zhuǎn)向橋的情況下，由轉(zhuǎn)向橫拉桿和左、右梯形臂組成的轉(zhuǎn)向梯形一般布置在前橋之后，當轉(zhuǎn)向輪處于與汽車直線行駛相應的中立位置時，梯形臂與橫拉桿在與道路平行的平面(水平面)內(nèi)的交角＞90。在發(fā)動機位置較低或轉(zhuǎn)向橋兼充驅(qū)動橋的情況下，為避免運動干涉，往往將轉(zhuǎn)向梯形布置在前橋之前，此時上述交角＜90，若轉(zhuǎn)向搖臂不是在汽車縱向平面內(nèi)前后擺動，而是在與道路平行的平面向左右搖動，則可將轉(zhuǎn)向直拉桿橫置，并借球頭銷直接帶動轉(zhuǎn)向橫拉桿，從而推使兩側(cè)梯形臂轉(zhuǎn)動。2）與獨立懸架配用的轉(zhuǎn)向傳動機構(gòu) 當轉(zhuǎn)向輪獨立懸掛時，每個轉(zhuǎn)向輪都需要相對于車架作獨立運動，因而轉(zhuǎn)向橋必須是斷開式的。與此相應，轉(zhuǎn)向傳動機構(gòu)中的轉(zhuǎn)向梯形也必須是斷開式的。3）轉(zhuǎn)向直拉桿轉(zhuǎn)向直拉桿的作用是將轉(zhuǎn)向搖臂傳來的力和運動傳給轉(zhuǎn)向梯形臂(或轉(zhuǎn)向節(jié)臂)。它所受的力既有拉力、也有壓力，因此直拉桿都是采用優(yōu)質(zhì)特種鋼材制造的，以保證工作可靠。在轉(zhuǎn)向輪偏轉(zhuǎn)或因懸架彈性變形而相對于車架跳動時，轉(zhuǎn)向直拉桿與轉(zhuǎn)向搖臂及轉(zhuǎn)向節(jié)臂的相對運動都是空間運動，為了不發(fā)生運動干涉，上述三者間的連接都采用球銷。