麦弗逊式独立悬架外文翻译_第1页
麦弗逊式独立悬架外文翻译_第2页
麦弗逊式独立悬架外文翻译_第3页
麦弗逊式独立悬架外文翻译_第4页
麦弗逊式独立悬架外文翻译_第5页
已阅读5页,还剩6页未读 继续免费阅读

下载本文档

版权说明:本文档由用户提供并上传,收益归属内容提供方,若内容存在侵权,请进行举报或认领

文档简介

1、独立悬架概论 轿车底盘的发展应该比发动机发展得快。加速性能不断改善,最高车速和转弯车速愈来愈高以及行驶减速度愈来愈大,要求有更加安全的底盘,独立悬架正是适合于此要求。它的主要优点是:a 需用空间小;b 前束的运动学变化及弹性运动学变化产生不足转向趋势;c 易于实现驱动轮的转向;d 质量小;e 左右车轮互不影响。 后两个特点对于获取良好的地面附着性特别是在起伏的路面作曲线行驶时尤为重要。independent wheel suspensions-generalthe chassis of a passenger car must be able to handle the engine powe

2、r installed. ever-improving acceleration, higher peak and cornering speeds, and deceleration lead to significantly increased requirements for safer chassis. independent wheel suspensions follow this trend. their main advantages are:a. little space requirementb. a kinematic and/or elastokinematic toe

3、-in change, tending towards under steering is possible(see section 3.6)c. easier steerability with existing drive;d. low weight;e. no mutual wheel influence.the last two characteristics are important for good road-holding, especially on bends with an uneven road surface.麦弗逊式悬架是双横臂式悬架的发展,汽车翼子板上的铰链点代替

4、了上横臂,减振器的活塞杆头和螺旋弹簧支承在这里。该铰点承受所有方向的力。这些力在活塞杆中引起弯曲变形。为了避免它引起的不利的外倾角变化和主销后倾变化,减振器活塞杆直径必须从11mm至少增大到20mm。如果不改变活塞杆直径,则通常采用双筒式减振器。 麦弗逊式悬架的主要优点在于所有承担弹性元件功能和车轮导向功能的零件可组合在一个结构单元里。这些零件是:a 支承螺旋弹簧下端的托盘;b 辅助弹簧11或压缩行程限位块;c 拉伸行程限位块;d 与拉杆5连接的摆轴式横向稳定杆;e 车轮转向节。 这些零件可通过熔焊或硬钎焊,或者是用螺栓固接在外套管上。麦弗逊式悬架的其他优点是:a 由于具有较大的有效距离c,作

5、用在车身连接点e和d处的力较小;b 点g和n之间只有很小的距离b;c 弹簧行程大;d 省去了三处支承;e 易于构造前部车底板形状。mcpherson struts and strut dampersthe mcpherson strut is a further development of double wishbone suspension. the upper transverse link is replaced by a pivot point on the wheel house panel, which takes the end of the coil spring. forc

6、es from all directions are concentrated at this point and these cause bending stress in the piston rod. to avoid detrimental elastic camber and caster changes, the normal rod diameter of 11 mm (in the shock absorber) must be increased to at least 18 mm. with a piston diameter of usually 30 mm or 32

7、mm the damper works on the twin-tube system and can be non-pressurized or pressurized (see section 5.8). the main advantage of the mcpherson strut is that all the parts providing the suspension and wheel control can be combined into one assembly. as can be seen in fig. 1.8, this includes:a. the spri

8、ng seat 3 to take the underside pf the coil spring;b. the auxiliary spring 11 or a bump stop (see fig.5.49);c. the rebound-travel stop (fig.5.54);d. the underslung anti-roll bar(7) via rod 5;e. the steering knuckle.the steering knuckle can be welded, brazed or bolted (fig.5.53) firmly to the outer t

9、ube (fig.1.56). further advantages are:a. lower forces in the body-side mounting points e and d due to a large effective distance c(fig.1.5);b. short distance b between points g and n (fig.3.30);c. long spring travel;d. three beating positions no longer needed;e. better design options on the front c

10、rumple zone; 近10年来,麦弗逊式悬架大都是用于前桥。但它也经常在前轮驱动车辆中用作后悬架。由于空气动力学缘故,汽车后尾上翘,这就允许活塞导向杆和活塞杆之间的导向长度较大。在图1.7所示的后悬架上:a 省去了滚动轴承;b 可采用较长的横臂,它几乎可伸到汽车中心线位置,从这样做的缺点是会使主销偏移距变大并为正值而使得外倾角变化和轮距变化合理,并使得加载时汽车的侧倾中心有微小的下降c 横臂外端点可深入车轮内,从而获得较小的距离b;d 行李箱深度可增大,并在采用减振器柱式还可加宽;e 然而,必须通过橡胶的硬度和恰当的横臂在转向节上固定点之间的距离来保证不产生不希望的弹性自转向现象。mcp

11、herson struts have become widely used as front axles, but they are also fitted as the rear suspension on front -wheel drive vehicles (e.g. ford mondeo sedan). the vehicle tail, which has been raised for aerodynamic reasons, allows a larger bearing span between the piston rod guide and piston. on the

12、 rear axle(fig.1.12).a. the upper strut mount is no longer necessary, as no steering movements occur.b. longer cross-members, which reach almost to the vehicle centre, can be used, producing better camber and track width change (fig.3.15 and 3.48) and a body roll centre that sinks less under load (f

13、ig. 3.30).c. the outer points of the braces can be drawn a long way into the wheel to achieve a shorter distance b.d. the boot can be dropped and, in the case of damper struts, also widened.e. however, rubber stiffness and the corresponding distance of the braces on the hub barriers (point 6 and 14

14、in fig.1.12) are needed to ensure that there is no unintentional elastic self-steer(figs 3.79 and 3.80).设计时应考虑采取措施减缓与这些优点相反而又难免的、对前轴不利的因素:a 不适合的运动特性;b 力和振动传递给汽车翼子板,从而传递给汽车头部;c 道路噪声难以隔绝为此需要采用一个支座;d 活塞杆和导向套之间产生的有害摩擦时弹性作用变差;e 上置的齿轮齿条式转向器横拉杆较长,从而增加了转向装置的费用;f 前轴对于轮胎的不平衡度和偏摆具有较大的敏感性;g 有时在减振器和轮胎之间仅有很小的空间。

15、但最后这点仅在前轮为驱动轮是才有影响,因为无法再装雪地防滑链。对于非驱动轮来说,空间紧缺至多是不允许装宽基轮胎。如果不得不采用这种轮胎,则需要车轮的压入深度e较小。nowadays, design measures have ensured that the advantages ate not outweighed by the inevitable disadvantages on the front axle. these disadvantages are:a. less favourable kinematic characteristics (sections 3.3 and 3.

16、5.2).b. introduction of forces and vibrations into the inner wheel house panel and therefore into a relatively elastic area of the front end of the vehicle. c. it is more difficult to insulate against road noise an upper strut mount is necessary (fig.1.9), which should be as decoupled as possible(fi

17、g,1,10,item 10 in fig.1.8 and item 6 in fig.1.56)d. the friction between piston rod and guide impairs the springing effect; it can be reduced by shortening distance b (figs 1.11 and 3.30).e. in the case of high-mounted rack and pinion steering, long tie rods and, consequently, more expensive steerin

18、g systems are required (figs 1.57 and 4.1); in addition, there is the unfavorable introduction of tie-rod forces in the middle of the shock-absorbing strut (see section 4.2.4) plus additional steering elasticity.f. greater sensitivity of the front axle to tyre imbalance and radial runout(see section

19、 2.5 and refs 1 and 4).g. greater clearance height requirement.h. sometimes the space between the tyres and the damping element (fig. 1.41) is very limited.this final constraint, however, is only important on front-wheel drive vehicles as it may cause problems with fitting snow chains. on non-driven

20、 wheels, at most the lack of space prevents wider tyres being fitted. if such tyres are absolutely necessary, disc-type wheels with a smaller wheel offset e are needed and these lead to a detrimentally larger positive or smaller negative kingpin offset at ground (fig.2.8 and 3.102). 图。 主销偏移距为负值和带有摆轴

21、式横向稳定杆的opel牌omega型和senator b型轿车左侧的麦弗逊式悬架的后视图。为了减小活塞杆2和导向套之间的摩擦,弹簧式斜置的,活塞杆和弹簧上托盘9通过一个可分离式支座10在e点固定在汽车翼子板上。 由于弹性塑料制成的辅助弹簧11与托盘9的内孔连接,下端支承在防尘罩12上,它放在弹簧托盘3上,并保护镀铬的杆2.当车轮上跳时,辅助弹簧压在管1的封盖上。 支架4和u形夹13焊接在管1上,横向稳定杆的拉杆5的上球铰固定在支架4内,u形夹则把车轮支架支承在u形弯脚中。为了能把外倾角精确地调整到设计值,u形夹的上孔加工成长形孔。车轮的导向由一个第二代双排径向止推滚珠轴承来承担。 导向铰g的转

22、向球销通过夹钳与车轮支架连接,横置的螺栓15穿过转向球销的环形槽,以防止球销在螺栓出现意外松动是滑脱。 副车架6是为了与车身连接而采用的。它不仅支承着横臂,在减振器专册中有详细介绍的发动机支座8以及横向稳定杆7的杆身也固定在它上面。fig.1.8 rear view of the left-hand side of the mcpherson front axle on the opel omega (1999) with negative kingpin offset at ground (scrub radius) and pendulum-linked anti-roll bar. th

23、e coil spring is offset from the mcpherson strut to decrease friction between piston rod 2 and the rod guide. part 2 and the upper spring seat 9 are fixed to the inner wheel house panel via the decoupled strut mount 10. the additional elastomer spring 11 is joined to seat 9 from the inside, and on t

24、he underside it carries the dust boot 12, which contacts the spring seat 3 and protects the chrome-plated piston rod 2. when the wheel bottoms out, the elastomer spring rests on the cap of the supporting tube 1. brackets 4 and 13 are welded to part 1, on which the upper ball joint of the anti-roll b

25、ar rod 5 is fastened from inside. bracket 13 takes the steering knuckle in between the u-shape side arms. the upper hole of bracket 13 has been designed as an elongated hole so that the camber can be set precisely at the factory (see fig.3.102). a second-generation double-row angular (contact) ball

26、bearing (item 14) controls the wheel. the ball pivot of the guiding joint g is joined to the steering knuckle by means of clamping forces. the transverse screw 15 grips into a ring groove of the joint bolt and prevents it from slipping out in the event of the screw loosening. the sub frame 6 is fixe

27、d to the body. in addition to the transverse control arms, details of which are given in ref.5. section 10.4, it also takes the engine mounts 8 and the back of the anti-roll bar 7. the drop centre rim is asymmetrical to allow negative wheel offset (not shown) at ground (scrub radius) (figs 2,10,2.11

28、 and 2.23).采用轴向滚珠轴承vw牌golf型和jetta 型轿车的弹簧柱支座。轴向滚珠轴承用来承受弹簧柱的转动。橡胶件用作隔声元件。压缩曲线在初始阶段呈线性,而在主要工作范围力在3kn至4kn之间曲线斜率急剧增大。图中标出了离散范围。 在安装流水线上,整个支座被压入汽车翼子板1的锥孔中。支座外圈的橡胶层2用于固紧连接,边圈3主要是考虑垂直方向必要的支撑。卡在托盘4上的橡胶坏5是为了在车轮完全放松落下时在板1上起限位作用,并以此保证必要的安全。fig. 1.9 mcpherson strut mount on the vw golf with a thrust ball bearing

29、, which permits the rotary movement of the mcpherson strut whereas the rubber anchorage improves noise insulation. initially the deflection curve remains linear and then becomes highly progressive in the main work area, which is between 3 kn and 4 kn. the graph shows the scatter. springing and dampi

30、ng forces are absorbed together so the support bearing si not decoupled (as in fig. 1.10). in the car final assembly line the complete strut mount is pressed into a conical sheet metal insert on the wheel house inside panel 1. the rubber layer 2 on the outside of the bearing ensures a firm seat and

31、the edge 3 gives the necessary hold in the vertical direction. the rubber ring 5 clamper on plate 4 operates when the wheel rebounds fully and so provides the necessary security (figure: lemfrder fahrwerktechnik ag).如果螺旋弹簧上的力和导向铰g上的力作用线不落在减振器中心线上,则弹簧柱与车身连接的点e上始终有横向力的作用。这个力在活塞导向套和活塞杆上引起反力和。=+,这个力愈大,作

32、用在活塞导向套上的摩擦力就愈大,从而使得推活塞杆下落所需的垂直力也要变大。 活塞头具有较大的直径,而且是在油中滑动。所以横向力在此仅起次要作用,而更小的力就几乎没有什么影响。通过把弹簧斜置,可以减小力。fig.1.11 if lateral force moves lever arm b round guiding joint g, the lateral force continually acts in the body-side fixing point e of the mcpherson strut as a result of the force . this generates

33、the reaction forces and on the piston rod guide and piston. this is += and the greater this force becomes, the further the frictional force increases in the piston rod guide and the greater the change in vertical force needed for it to rip away. as the piston has a large diameter and also slides in

34、shock-absorber fluid, lateral force plays only a subordinate role (see fig.5.54). can be reduced by offsetting the springs at an angle and shortening the distance b (see figs 1.56 and 3.30, and equation 3.4a).lancia-delta 型车的麦弗逊式后悬架。该悬架的横臂较长,在横臂15上的固定点非常靠里面,横梁断面呈板状。为了保证准确的直线行驶,必须是车轮支架上点6和点14之间的距离尽可能大。纵臂16的固定点13和

温馨提示

  • 1. 本站所有资源如无特殊说明,都需要本地电脑安装OFFICE2007和PDF阅读器。图纸软件为CAD,CAXA,PROE,UG,SolidWorks等.压缩文件请下载最新的WinRAR软件解压。
  • 2. 本站的文档不包含任何第三方提供的附件图纸等,如果需要附件,请联系上传者。文件的所有权益归上传用户所有。
  • 3. 本站RAR压缩包中若带图纸,网页内容里面会有图纸预览,若没有图纸预览就没有图纸。
  • 4. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途。
  • 5. 人人文库网仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对用户上传分享的文档内容本身不做任何修改或编辑,并不能对任何下载内容负责。
  • 6. 下载文件中如有侵权或不适当内容,请与我们联系,我们立即纠正。
  • 7. 本站不保证下载资源的准确性、安全性和完整性, 同时也不承担用户因使用这些下载资源对自己和他人造成任何形式的伤害或损失。

评论

0/150

提交评论