转向系统【中文2070字】【中英文WORD】.zip

【中文 2070 字】转向系统 汽车转向系统：汽车上用来改变或恢复其行驶方向的专设机构称为汽车转向系统。汽车的转向系统是用来改变汽车行驶方向和保持汽车直线行驶的机构基本组成(1)转向操纵机构主要由转向盘、转向轴、转向管柱等组成。(2)转向器将转向盘的转动变为转向摇臂的摆动或齿条轴的直线往复运动，并对转向操纵力进行放大的机构。转向器一般固定在汽车车架或车身上，转向操纵力通过转向器后一般还会改变传动方向。(3)转向传动机构将转向器输出的力和运动传给车轮(转向节)，并使左右车轮按一定关系进行偏转的机构。类型按转向能源的不同，转向系统可分为机械转向系统和动力转向系统两大类。机械转向系：由转向器和转向传动机构组成.转向器：由方向盘，方向盘转向轴，转向啮合付(转向器)组成.转向传动机构：由转向臂(转向垂臂)，直拉杆，直拉杆臂，左右梯形臂，横拉杆，若干球头关节组成.动力转向系：由机械转向系加转向加力装置构成.1机械转向系 机械转向系以驾驶员的体力作为转向能源，其中所有传力件都是机械的。机械转向系由转向操纵机构、转向器和转向传动机构三大部分组成。（1）转向操纵机构 转向操纵机构由方向盘、转向轴、转向管柱等组成，它的作用是将驾驶员转动转向盘的操纵力传给转向器。（2）转向器 转向器(也常称为转向机)是完成由旋转运动到直线运动(或近似直线运动)的一组齿轮机构，同时也是转向系中的减速传动装置。目前较常用的有齿轮齿条式、循环球曲柄指销式、蜗杆曲柄指销式、循环球-齿条齿扇式、蜗杆滚轮式等。我们主要介绍前几种。1）齿轮齿条式转向器 齿轮齿条式转向器分两端输出式和中间（或单端）输出式两种。两端输出的齿轮齿条式转向器，作为传动副主动件的转向齿轮轴通过轴承和安装在转向器壳体中，其上端通过花键与万向节叉和转向轴连接。与转向齿轮啮合的转向齿条水平布置，两端通过球头座与转向横拉杆相连。弹簧通过压块将齿条压靠在齿轮上，保证无间隙啮合。弹簧的预紧力可用调整螺塞调整。当转动转向盘时，转向器齿轮转动，使与之啮合的齿条沿轴向移动，从而使左右横拉杆带动转向节左右转动，使转向车轮偏转，从而实现汽车转向。中间输出的齿轮齿条式转向器，其结构及工作原理与两端输出的齿轮齿条式转向器基本相同，不同之处在于它在转向齿条的中部用螺栓与左右转向横拉杆相连。在单端输出的齿轮齿条式转向器上，齿条的一端通过内外托架与转向横拉杆相连。2）循环球式转向器 循环球式转向器是目前国内外应用最广泛的结构型式之一，一般有两级传动副，第一级是螺杆螺母传动副，第二级是齿条齿扇传动副。为了减少转向螺杆转向螺母之间的摩擦，二者的螺纹并不直接接触，其间装有多个钢球，以实现滚动摩擦。转向螺杆和螺母上都加工出断面轮廓为两段或三段不同心圆弧组成的近似半圆的螺旋槽。二者的螺旋槽能配合形成近似圆形断面的螺旋管状通道。螺母侧面有两对通孔，可将钢球从此孔塞入螺旋形通道内。转向螺母外有两根钢球导管，每根导管的两端分别插入螺母侧面的一对通孔中。导管内也装满了钢球。这样，两根导管和螺母内的螺旋管状通道组合成两条各自独立的封闭的钢球流道。转向螺杆转动时，通过钢球将力传给转向螺母，螺母即沿轴向移动。同时，在螺杆及螺母与钢球间的摩擦力偶作用下，所有钢球便在螺旋管状通道内滚动，形成球流。在转向器工作时，两列钢球只是在各自的封闭流道内循环，不会脱出。3）蜗杆曲柄指销式转向器 蜗杆曲柄指销式转向器的传动副(以转向蜗杆为主动件，其从动件是装在摇臂轴曲柄端部的指销。转向蜗杆转动时，与之啮合的指销即绕摇臂轴轴线沿圆弧运动，并带动摇臂轴转动。（3）转向传动机构 转向传动机构的功用是将转向器输出的力和运动传到转向桥两侧的转向节，使两侧转向轮偏转，且使二转向轮偏转角按一定关系变化，以保证汽车转向时车轮与地面的相对滑动尽可能小。1）与非独立悬架配用的转向传动机构 与非独立悬架配用的转向传动机构主要包括转向摇臂、转向直拉杆、转向节臂、和转向梯形。在前桥仅为转向桥的情况下，由转向横拉杆和左、右梯形臂组成的转向梯形一般布置在前桥之后，当转向轮处于与汽车直线行驶相应的中立位置时，梯形臂与横拉杆在与道路平行的平面(水平面)内的交角90。在发动机位置较低或转向桥兼充驱动桥的情况下，为避免运动干涉，往往将转向梯形布置在前桥之前，此时上述交角90，若转向摇臂不是在汽车纵向平面内前后摆动，而是在与道路平行的平面向左右摇动，则可将转向直拉杆横置，并借球头销直接带动转向横拉杆，从而推使两侧梯形臂转动。2）与独立悬架配用的转向传动机构 当转向轮独立悬挂时，每个转向轮都需要相对于车架作独立运动，因而转向桥必须是断开式的。与此相应，转向传动机构中的转向梯形也必须是断开式的。3）转向直拉杆 转向直拉杆的作用是将转向摇臂传来的力和运动传给转向梯形臂(或转向节臂)。它所受的力既有拉力、也有压力，因此直拉杆都是采用优质特种钢材制造的，以保证工作可靠。在转向轮偏转或因悬架弹性变形而相对于车架跳动时，转向直拉杆与转向摇臂及转向节臂的相对运动都是空间运动，为了不发生运动干涉，上述三者间的连接都采用球销。Steering system(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 wheels rotation steering arms 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 pilots 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 wheels 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 outputs 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.Springs 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 racks middle with the bolt with about to be connected.On single-ended outputs gear rack type diverter,a racks end with changes the steering knuckle tie rod through the inside and outside bracket to be connected.2)Follows round the world-like the divertor Follows 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 nuts friction,the twos 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 twos 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 pipes 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 nuts 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 diverter The worm bearing adjuster crank refers to sells the type diverters 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 system Steering 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 axles 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.,As shown in Figure 9 b.If Pitman is not in the vehicle longitudinal plane backwards and forwards,but is in the plane parallel to the road to shake,you can bring the steering linkage 3 exhaust,and ball head pin directly driven steering tie rod 6,thus pushing the sides of a trapezoid arm.2)and independent suspension with the steering linkage when steering wheel independent suspension,each steering wheel needs relative to the frame for independence movement,thereby steering bridge must be disconnected.And accordingly,steering linkage of steering or must be disconnected.The role of steering lever is passed from the Pitman force and motion to steering arm(or steering).It force existing tension and pressure,so direct lever is is the use of high-quality special steel manufacturing,in order to ensure reliable operation.Linkage of typical structure as shown in Figure 11.In the steering wheel to deflect or elastic deformation due to the suspension and relative to the frame beats,steering lever and Pitman and steering relative movements are spatial movement,in order not to occur,the interference of the three connections takes the ball PIN.4)Steering damper as speed increases,the modern automobile steering wheel sometimes generate shimmy(steering wheel around the kingpin axis reciprocating swing,even whole body vibration),which not only affect vehicle stability,but also affected comfort,aggravate the nose wheel wear and tear.In the steering linkage in setting steering damper is to overcome the steering wheel shimmy of effective measures.Steering damper side of the body(or front axle)articulated,the other end and steering lever(or articulated steering).Use mechanical steering can implement steering,when steering axle load larger that the pilots manual as steering energy is difficult to turn smoothly.Power steering system is in mechanical steering system on the basis of a set of steering device.Steering device reduces driver operated steering wheel.Steering energy from the drivers physical strength and motor(or motors),engine(or motors)accounted for the major part,through the steering device.Normally,pilots can easily control the steering.But in the steering device failure,I went back to mechanical steering system state,in general but also by the drivers steering tasks independently.(1)hydraulic power steering systems-which belongs to the steering device part is:steering pump 7,steering tubing 8,steering,and is located in the integral oil tank 6 EPS 4 internal steering control valve and steering power cylinder 5,etc.When the pilot turned the steering wheel 1 by mechanical steering makes steering tie rod 9 mobile,and driven steering,the steering wheel deflection,thus changing the car driving direction.At the same time,the steering shaft also driven steering internal rotation of the steering control valve,the hydraulic steering power cylinder produces helps the drivers steering forces.Because of the role of the steering device,the driver simply than mechanical steering system is much smaller,steering torque of the steering wheel deflection.Advantages and disadvantages:high energy consumption,especially when slow turning,think the comparison engine driving direction also relatively easy.And because the hydraulic pump pressure,is also easier to damage to the power system.(2)electric power steering system,referred to as EPS or EPS(electric,Electronic Power Steering system)in mechanical steering mechanism,increase signal sensor,electronic control unit and the Steering Body.EPS is the use of electric motor as a power source,depending on the speed of help and steering parameters,and other factors,by the electronic control unit to complete the power-assisted control,its principles can be summarized as follows:when handling and steering wheel,mounted on the steering wheel shaft torque sensor constantly measured steering shaft torque signal,the signal and the vehicle speed signal input to the electronic control unit.The electronic control unit according to the input signal,determine power torque in magnitude and direction,which is the selected motor currents and rotation direction,adjusting the size of the auxiliary power steering.Motor torque by electromagnetic clutch by gear reducer by moments later,the cars steering mechanism,to achieve a vehicle condition of steering forces.For example,Foxs EHPAS e hydraulic system from a computer according to engine speed and vehicle speed and steering angle and other signal,drive e pump to deliver power steering system.Power feel very natural.So many people on Fox in the direction of the feeling is quite good,feeling of steering control can be as long as you want.Some vehicles also claims the use of electronic power,but just motor power,no hydraulic aided,prone to noise.Power effects are far behind Fox this type of electronic power.