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三自由度 圆柱坐标式液压驱动
三菱PLC
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关节式自动上下料机械手设计【三自由度
圆柱坐标式液压驱动】【三菱PLC】【CAD图纸和文档全套可预览】
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1The Effect of a Viscous Coupling Used as a Front-Wheel Drive Limited-Slip Differential on Vehicle Traction and Handling1 ABCTRACTThe viscous coupling is known mainly as a driveline component in four wheel drive vehicles. Developments in recent years, however, point toward the probability that this device will become a major player in mainstream front-wheel drive application. Production application in European and Japanese front-wheel drive cars have demonstrated that viscous couplings provide substantial improvements not only in traction on slippery surfaces but also in handing and stability even under normal driving conditions.This paper presents a serious of proving ground tests which investigate the effects of a viscous coupling in a front-wheel drive vehicle on traction and handing. Testing demonstrates substantial traction improvements while only slightly influencing steering torque. Factors affecting this steering torque in front-wheel drive vehicles during straight line driving are described. Key vehicle design parameters are identified which greatly influence the compatibility of limited-slip differentials in front-wheel drive vehicles.Cornering tests show the influence of the viscous coupling on the self steering behavior of a front-wheel drive vehicle. Further testing demonstrates that a vehicle with a viscous limited-slip differential exhibits an improved stability under acceleration and throttle-off maneuvers during cornering.2 THE VISCOUS COUPLINGThe viscous coupling is a well known component in drivetrains. In this paper only a short summary of its basic function and principle shall be given.The viscous coupling operates according to the principle of fluid friction, and is thus dependent on speed difference. As shown in Figure 1 the viscous coupling has slip controlling properties in contrast to torque sensing systems.This means that the drive torque which is transmitted to the front wheels is automatically controlled in the sense of an optimized torque distribution.In a front-wheel drive vehicle the viscous coupling can be installed inside the differential or externally on an intermediate shaft. The external solution is shown in Figure 2.This layout has some significant advantages over the internal solution. First, 2there is usually enough space available in the area of the intermediate shaft to provide the required viscous characteristic. This is in contrast to the limited space left in todays front-axle differentials. Further, only minimal modification to the differential carrier and transmission case is required. In-house production of differentials is thus only slightly affected. Introduction as an option can be made easily especially when the shaft and the viscous unit is supplied as a complete unit. Finally, the intermediate shaft makes it possible to provide for sideshafts of equal length with transversely installed engines which is important to reduce torque steer (shown later in section 4).This special design also gives a good possibility for significant weight and cost reductions of the viscous unit. GKN Viscodrive is developing a low weight and cost viscous coupling. By using only two standardized outer diameters, standardized plates, plastic hubs and extruded material for the housing which can easily be cut to different lengths, it is possible to utilize a wide range of viscous characteristics. An example of this development is shown in Figure 3.3 TRACTION EFFECTSAs a torque balancing device, an open differential provides equal tractive effort to both driving wheels. It allows each wheel to rotate at different speeds during cornering without torsional wind-up. These characteristics, however, can be disadvantageous when adhesion variations between the left and right sides of the road surface (split-) limits the torque transmitted for both wheels to that which can be supported by the low- wheel.With a viscous limited-slip differential, it is possible to utilize the higher adhesion potential of the wheel on the high-surface. This is schematically shown in Figure 4.When for example, the maximum transmittable torque for one wheel is exceeded on a split-surface or during cornering with high lateral acceleration, a speed difference between the two driving wheels occurs. The resulting self-locking torque in the viscous coupling resists any further increase in speed difference and transmits the appropriate torque to the wheel with the better traction potential.It can be seen in Figure 4 that the difference in the tractive forces results in a yawing moment which tries to turn the vehicle in to the low-side, To keep the vehicle in a straight line the driver has to compensate this with opposite steering input. Though the fluid-friction principle of the viscous coupling and the resulting soft 3transition from open to locking action, this is easily possible, The appropriate results obtained from vehicle tests are shown in Figure 5.Reported are the average steering-wheel torque Ts and the average corrective opposite steering input required to maintain a straight course during acceleration on a split-track with an open and a viscous differential. The differences between the values with the open differential and those with the viscous coupling are relatively large in comparison to each other. However, they are small in absolute terms. Subjectively, the steering influence is nearly unnoticeable. The torque steer is also influenced by several kinematic parameters which will be explained in the next section of this paper.4 FACTORS AFFECTING STEERING TORQUEAs shown in Figure 6 the tractive forces lead to an increase in the toe-in response per wheel. For differing tractive forces, Which appear when accelerating on split-with limited-slip differentials, the toe-in response changes per wheel are also different.Unfortunately, this effect leads to an undesirable turn-in response to the low-side, i.e. the same yaw direction as caused by the difference in the tractive forces.Reduced toe-in elasticity is thus an essential requirement for the successful front-axle application of a viscous limited-slip differential as well as any other type of limited-slip differential.Generally the following equations apply to the driving forces on a wheelVTFF With Tractive ForceTF Vertical Wheel LoadVF Utilized Adhesion CoefficientThese driving forces result in steering torque at each wheel via the wheel disturbance level arm “e” and a steering torque difference between the wheels given by the equation:=eTloHhiHFFecosWhere Steering Torque DifferenceeT e=Wheel Disturbance Level Arm King Pin Angle4 hi=high-side subscript lo=low-side subscriptIn the case of front-wheel drive vehicles with open differentials, Ts is almost unnoticeable, since the torque bias () is no more than 1.35.loHhiTFF/For applications with limited-slip differentials, however, the influence is significant. Thus the wheel disturbance lever arm e should be as small as possible. Differing wheel loads also lead to an increase in Te so the difference should also be as small as possible.When torque is transmitted by an articulated CV-Joint, on the drive side (subscript 1) and the driven side (subscript 2),differing secondary moments are produced that must have a reaction in a vertical plane relative to the plane of articulation. The magnitude and direction of the secondary moments (M) are calculated as follows (see Figure 8):Drive side M1 =vvTTtan/)2/tan(2Driven side M2 =vvTTtan/)2/tan(2With T2 =dynTrF =TsystemJoTfint, 2Where Vertical Articulation Anglev Resulting Articulation Angle Dynamic Wheel Radiusdynr Average Torque LossTThe component acts around the king-pin axis (see figure 7) as a cos2Msteering torque per wheel and as a steering torque difference between the wheels as follows:)tan/2/tan()sin/2/tan(cos22liwhiwTTTTT where Steering Torque DifferenceT WWheel side subscriptIt is therefore apparent that not only differing driving torque but also differing 5articulations caused by various driveshaft lengths are also a factor. Referring to the moment-polygon in Figure 7, the rotational direction of M2 or respectively change, Tdepending on the position of the wheel-center to the gearbox output.For the normal position of the halfshaft shown in Figure 7(wheel-center below the gearbox output joint) the secondary moments work in the same rotational direction as the driving forces. For a modified suspension layout (wheel-center above gearbox output joint, i.e. negative) the secondary moments counteract the moments caused vby the driving forces. Thus for good compatibility of the front axle with a limited-slip differential, the design requires: 1) vertical bending angles which are centered around or negative () with same values of on both left and right sides; and 2) 0v0vvsideshafts of equal length.The influence of the secondary moments on the steering is not only limited to the direct reactions described above. Indirect reactions from the connection shaft between the wheel-side and the gearbox-side joint can also arise, as shown below:Figure 9: Indirect Reactions Generated by Halfshaft Articulation in the Vertical PlaneFor transmission of torque without loss and both of the secondary vdvwmoments acting on the connection shaft compensate each other. In reality (with torque loss), however, a secondary moment difference appears: WDDWMMM12With TTTWD22The secondary moment difference is:DWMVWWVWWVDVDWTTDTwTTtan/2/tansin/tan22/2For reasons of simplification it apply that and to VVWVDTTTWDgiveVVVDWTMtan/1sin/12/tan requires opposing reaction forces on both joints where DWM. Due to the joint disturbance lever arm f, a further steering torque LMFDWDW/also acts around the king-pin axis:LfMTDWf/cos6loloDWhihiDWfLMLMfT/cosWhere Steering Torque per WheelfT Steering Torque DifferencefT Joint Disturbance Leverf Connection shaft (halfshaft) LengthLFor small values of f, which should be ideally zero, is of minor influence.fT5EFFECT ON CORNERINGViscous couplings also provide a self-locking torque when cornering, due to speed differences between the driving wheels. During steady state cornering, as shown in figure 10, the slower inside wheel tends to be additionally driven through the viscous coupling by the outside wheel.Figure 10: Tractive forces for a front-wheel drive vehicle during steady state cornering The difference between the Tractive forces Dfr and Dfl results in a yaw moment MCOG, which has to be compensated by a higher lateral force, and hence a larger slip angle af at the front axle. Thus the influence of a viscous coupling in a front-wheel drive vehicle on self-steering tends towards an understeering characteristic. This behavior is totally consistent with the handling bias of modern vehicles which all under steer during steady state cornering maneuvers. Appropriate test results are shown in figure 11.Figure 11: comparison between vehicles fitted with an open differential and viscous coupling during steady state cornering.The asymmetric distribution of the tractive forces during cornering as shown in figure 10 improves also the straight-line running. Every deviation from the straight-line position causes the wheels to roll on slightly different radii. The difference between the driving forces and the resulting yaw moment tries to restore the vehicle to straight-line running again (see figure 10).Although these directional deviations result in only small differences in wheel travel radii, the rotational differences especially at high speeds are large enough for a viscous coupling front differential to bring improvements in straight-line running.High powered front-wheel drive vehicles fitted with open differentials often spin 7their inside wheels when accelerating out of tight corners in low gear. In vehicles fitted with limited-slip viscous differentials, this spinning is limited and the torque generated by the speed difference between the wheels provides additional tractive effort for the outside driving wheel. this is shown in figure 12Figure 12: tractive forces for a front-wheel drive vehicle with viscous limited-slip differential during acceleration in a bend The acceleration capacity is thus improved, particularly when turning or accelerating out of a T-junction maneuver ( i.e. accelerating from a stopped position at a “T” intersection-right or left turn ).Figures 13 and 14 show the results of acceleration tests during steady state cornering with an open differential and with viscous limited-slip differential .Figure 13: acceleration characteristics for a front-wheel drive vehicle with an open differential on wet asphalt at a radius of 40m (fixed steering wheel angle throughout test).Figure 14: Acceleration Characteristics for a Front-Wheel Drive Vehicle with Viscous Coupling on Wet Asphalt at a Radius of 40m (Fixed steering wheel angle throughout test)The vehicle with an open differential achieves an average acceleration of 2.0 while the2/smvehicle with the viscous coupling reaches an average of 2.3 (limited by 2/smengine-power). In these tests, the maximum speed difference, caused by spinning of the inside driven wheel was reduced from 240 rpm with open differential to 100 rpm with the viscous coupling.During acceleration in a bend, front-wheel drive vehicles in general tend to understeer more than when running at a steady speed. The reason for this is the reduction of the potential to transmit lateral forces at the front-tires due to weight transfer to the rear wheels and increased longitudinal forces at the driving wheels. In an open loop control-circle-test this can be seen in the drop of the yawing speed (yaw rate) after starting to accelerate (Time 0 in Figure 13 and 14). It can also be taken from Figure 13 and Figure 14 that the yaw rate of the vehicle with the open differential falls-off more rapidly than for the vehicle with the viscous coupling starting to accelerate. Approximately 2 seconds after starting to accelerate, however, the yaw rate fall-off gradient of the viscous-coupled vehicle increases more than at the 8vehicle with open differential.The vehicle with the limited slip front differential thus has a more stable initial reaction under accelerating during cornering than the vehicle with the open differential, reducing its understeer. This is due to the higher slip at the inside driving wheel causing an increase in driving force through the viscous coupling to the outside wheel, which is illustrated in Figure 12. the imbalance in the front wheel tractive forces results in a yaw moment acting in direction of the turn, countering the CSDMundersteer.When the adhesion limits of the driving wheels are exceed, the vehicle with the viscous coupling understeers more noticeably than the vehicle with the open differential (here, 2 seconds after starting to accelerate). On very low friction surfaces, such as snow or ice, stronger understeer is to be expected when accelerating in a curve with a limited slip differential because the driving wheels-connected through the viscous coupling-can be made to spin more easily (power-under-steering). This characteristic can, however, be easily controlied by the driver or by an automatic throttle modulating traction control system. Under these conditions a much easier to control than a rear-wheel drive car. Which can exhibit power-oversteering when accelerating during cornering. All things, considered, the advantage through the stabilized acceleration behavior of a viscous coupling equipped vehicle during acceleration the small disadvantage on slippery surfaces.Throttle-off reactions during cornering, caused by releasing the accelerator suddenly, usually result in a front-wheel drive vehicle turning into the turn (throttle-off oversteering ). High-powered modeles which can reach high lateral accelerations show the heaviest reactions. This throttle-off reaction has several causes such as kinematic influence, or as the vehicle attempting to travel on a smaller cornering radius with reducing speed. The essential reason, however, is the dynamic weight transfer from the rear to the front axle, which results in reduced slip-angles on the front and increased slip-angles on the rear wheels. Because the rear wheels are not transmitting driving torque, the influence on the rear axle in this case is greater than that of the front axle. The driving forces on the front wheels before throttle-off (see Figure 10) become over running or braking forces afterwards, which is illustrated for the viscous equipped vehicle in Figure 15.Figure 15:Baraking Forces for a Front-Wheel Drive Vehicle with Viscous 9Limited-Slip Differential Immediately after a Throttle-off Maneuver While CorneringAs the inner wheel continued to turn more slowly than the outer wheel, the viscous coupling provides the outer wheel with the larger braking force . The force fBdifference between the front-wheels applied around the center of gravity of the vehicle causes a yaw moment that counteracts the normal turn-in reaction.GCM0When cornering behavior during a throttle-off maneuver is compared for vehicles with open differentials and viscous couplings, as shown in Figure 16 and 17, the speed difference between the two driving wheels is reduced with a viscous differential.Figure 16: Throttle-off Characteristics for a Front-Wheel Drive Vehicle with an open Differential on Wet Asphalt at a Radius of 40m (Open Loop)Figure 17:Throttle-off Characteristics for a Front-Wheel Drive Vehicle with Viscous Coupling on Wet Asphalt at a Radius of 40m (Open Loop)The yawing speed (yaw rate), and the relative yawing angle (in addition to the yaw angle which the vehicle would have maintained in case of continued steady state cornering) show a pronounced increase after throttle-off (Time=0 seconds in Figure 14 and 15) with the open differential. Both the sudden increase of the yaw rate after throttle-off and also the increase of the relative yaw angle are significantly reduced in the vehicle equipped with a viscous limited-slip differential.A normal driver os a front-wheel drive vehicle is usually only accustomed to neutral and understeering vehicle handing behavior, the driver can then be surprised by sudden and forceful oversteering reaction after an abrupt release of the throttle, for example in a bend with decreasing radius. This vehicle reaction is further worsened if the driver over-corrects for the situation. Accidents where cars leave the road to the inner side of the curve is proof of this occurrence. Hence the viscous coupling improves the throttle-off behavior while remaining controllable, predictable, and safer for an average driver.6. EFFECT ON BRAKING The viscous coupling in a front-wheel drive vehicle without ABS (anti-lock braking system) has only a very small influence on the braking behavior on split- surfaces. Hence the front-wheels are connected partially via the front-wheel on the low- side is slightly higher than in an vehicle with an open differential. On the other side ,the brake pressure to lock the front-wheel on the high- side is slightly lower. 10These differences can be measured in an instrumented test vehicle but are hardly noticeable in a subjective assessment. The locking sequence of front and rear axle is not influenced by the viscous coupling.Most ABS offered today have individual control of each front wheel. Electronic ABS in front-wheel drive vehicles must allow for the considerable differences in effective wheel inertia between braking with the clutch engaged and disengaged.Partial coupling of the front wheels through the viscous unit does not therefore compromise the action of the ABS - a fact that has been confirmed by numerous tests and by several independent car manufacturers. The one theoretical exception to this occurs on a split-surface if a yaw moment build-up delay or Yaw Moment Reduction(YMR) is included in the ABS control unit. Figure 18 shows typical brake pressure sequences, with and without YMR.figure 18: brake pressure build-up characteristics for the front brakes of a vehicle braking on split- with ABS. In vehicles with low yaw inertia and a short wheelbase, the yaw moment build-up can be delayed to allow an average driver enough reaction time by slowing the brake pressure build-up over the ABS for the high- wheel. The wheel on the surface with the higher friction coefficient is therefore, particularly at the beginning of braking, under-braked and runs with less slip. The low- wheel, in contrast, can at the same time have a very high slip, which results in a speed difference across the viscous differential. The resulting self-locking torque then appears as an extra braking force at the high- wheel which counteracts the YMR.Although this might be considered as a negative effect and can easily be corrected when setting the YMR algorithm for a vehicle with a front viscous coupling, vehicle tests have proved that the influence is so slight that no special development of new ABS/YMR algorithms are actually needed. Some typical averaged test results are summarized in Figure 19.figure 19 : results form ABS braking tests with YMR on split-(Vo=50 mph, 3rd Gear, closed loop ) in figure 19 on the left a comparison of the maximum speed difference which occurred in the first ABS control cycle during braking is shown. It is obvious that the viscous coupling is reducing this speed difference. As the viscous coupling counteracts the YMR, the required steering wheel angle to keep the vehicle 11in straight direction in the first second of braking increased from 39 to 51 (figure 19,middle). Since most vehicle and ABS manufacturers consider 90 to be the critical limit, this can be tolerated. Finally, as the self-locking torque produced by the viscous coupling causes an increase in high-. Wheel braking force, a slightly higher vehicle deceleration was maintained(figure 19,right).7 SUMMARYin conclusion,it can be established that the application of a viscous coupling in a front-axle differential. It also positively influences the complete vehicle handling and stability , with only slight, but acceptable influence on torques-steer. To reduce unwanted torque-steer effects a basic set of design rules have been established: Toe-in response due to longitudinal load change must be as small as possible . Distance between king-pin axis and wheel center has to be as small as possible. Vertical bending angle-rang should be centered around zero(or negative). vertical bending angles should be the same for both sides. Sideshafts should be of equal length.Of minor influence on torque-steer is the joint disturbance lever arm which should be ideally zero for other reasons anyway. Braking with and without ABS is only negligibly influenced by the viscous coupling. Traction is significantly improved by the viscous limited slip differential in a front-wheel drive vehicle.12The self-steering behavior of a front-wheel drive vehicle is slightly influenced by a viscous limited slip differential in the direction of understeer. The improved reactions to throttle-off and acceleration during cornering make a vehicle with viscous coupling in the front-axle considerably more stable, more predictable and therefore safer.131 基本概念 黏性连接器主要地被认为是在四轮驱动的汽车上驱动路线的一部件。然而，在近些年的发展中，施用在前轮驱动的趋势中将成为重要角色的观点是可能的。在欧洲和日本前轮驱动轿车产量的施用已经证明黏性连接器不仅对于光滑路面的汽车牵引，而且在正常行驶条件下对于操纵性和稳定性都有所改善。这篇文章展示出调查黏性连接器对汽车牵引和操纵的影响的重大检验场试验，试验证明大多数牵引的改善仅仅轻微地影响转向装置的扭转力。前轮驱动的汽车在直线行驶时影响发动机转矩的因素被描述出来。在前轮驱动的汽车上极大地影响限制滑移差速器适合性的关键汽车设计参数被确定。转弯试验展现出黏性连接器在前轮驱动的汽车上独立转弯时的影响。进一步的试验证明安装黏性限制滑移差速器的汽车在加速和转弯时节气门频繁关闭的 情况下显示出一个改善的稳定性。2 黏性连接器 黏性连接器被广泛认为是驱动列车的一组成部件。在这篇文章中仅仅给出它的基本功能和原理的简明概要。黏性连接器是根据液体摩擦的原理和依靠速度差来运转的。正如图 1 所示黏性连接器的滑动控制特性和驱动观察系统的对比。这表明传送到前轮的驱动扭转力是由一个优化的扭转力分配检测器自动控制的。在前轮驱动的汽车上黏性连接器可以安装在差速器的内侧或者一根中间轴的外面。外面的方式如图 2 所示。内部的这种设计方式有很大的优点。首先，在中间轴区域可以得到足够的空间来提供符合要求的黏性特性。这和当今前轮轴差速器只留下有限的空间相对比。其次，差速器架和转送轴套只需要很小的修改。而且差速器壳体的生产也仅仅只有一点影响。引用作为一个选择性的事很容易做到尤其当轴和黏性单元作为一个整体单元被共给时。最后，中间轴使为等长的的侧偏轴提供横向安装发动机是可能的，横向地安装发动机对于减小扭转力的操纵是很重要的（后面第四部分说明了） 。14这种特殊的设计也为有实际意义的重量和黏性单元费用的降低给出了很好的可能性。GKN Viscodrive 正在发展一种低重量和低成本的黏性连接器。通过使用仅仅两个标准化的直径、标准化的盘，塑料轮毂和挤压成型的材料造成的储存室它能很容易地被截成不同的长度，使用一个宽的黏性范围是可能的。在图 3 中显示出这种发展的一个例子。3 牵引力的影响作为一个扭转力平衡装置，一个开的差速器提供相等的力到两个驱动轮上。它也允许每个车轮在扭转没结束转弯时以不同的速度转动。然而，这种特性当道路表面滑动系数为限制扭转力传递到两轮的左、右附着变动时是不利的，它能被低滑动系数的轮子支持。安装黏性限制滑移差速器,在高的值的路面上它可能利用高车轮附着潜在性.这在图 4 中显示出。例如，当一个车轮传递的最大扭转力超出表面滑动系数允许值或者以一个高的侧面加速度转弯时，两个车轮的速度是不同的.在黏性连接器中产生的自锁扭转力抵抗速度差的增加并且传递合适的扭转力到车轮上它具有更好的牵引力潜能。在图 4 中可以看出牵引力的不同导致汽车瞬间向低滑动系数值()一侧跑偏，为了保持汽车直线行驶驾驶员必须施加一个相反的扭转力来补偿。通过黏性连接器的液体摩擦原理和从打开到锁死柔和的传递结果,这是很可能的，从汽车实验中得到的合适结果如图 5 所示。报告称平均操纵轮扭转力和为保持带有一个开式的并且黏性的差速器在ST加速期间在滑动系数的路面上直线行驶应输入的平均正确的相对的转向操纵。相互对照开式差速器和那些黏性连接器是相对大的。然而，在绝对条件下它们是小的。主观地说，转向装置的影响是不明显的。扭转力操纵也受几个运动参数影响这些参数将在这篇文章下个部分解释。4 影响转向装置扭转力的因素 如图 6 所示牵引力引起一个从头到尾的增加来反应每个车轮。因为带有限15制滑动差速器的车轮在滑动系数的路面上加速时会出现不同的牵引力，所以从头到尾反应每个车轮的变化也是不同的。不幸的是，这个作用将导致一个不期望的朝低滑动系数一侧的反应，也就是说在不同的牵引力下产生相同的跑偏方向。降低从头到尾的弹力是黏性限制滑动差速器像其它任何形式差速器一样在前轴的成功应用所必须具备的。普遍地用下面的公式计算一个车轮的驱动力TVFF 牵引力TF车轮垂直载荷VF利用的附着系数这些驱动力导致在车轮之间每个车轮的转向装置扭转力经过车轮干扰常数e 干扰后与每个车轮的转向装置扭转力是不同的，给出下面的等式。cos()ioeH hH lTeFF 这里 扭转力矩差值eT e车轮干扰常数 主销倾角高滑动系数一侧下标ih低滑动系数一侧下标ol 在带有开式差速器前轮驱动汽车的情况下，是很不明显的，因为扭转力ST基数是不大于 1.35 的。(/)H hiH loFF然而，因为应用了限制滑动差速器，这个影响是很有意义的。这样车轮干扰常数 e 就应该尽可能的小。不同的车轮载荷也会导致的增加所以差别也eTAeTA要尽可能的小。当扭转力通过铰接“CV 连接”传递时，在主动一侧（下标 1）和从动一侧16（下标 2） ，必须反应垂直平面相对于连接平面的不同的第二个力矩产生了。第二个力矩（M）大小和方向用于下面的式子计算（如图 8）：主动一侧12tan(/2)/tanvvMTTA从动一侧 22tan(/2)/tanvvMTTA2TdynTF rA2(,Tf T连接系统）这里 纵向连接角v 产生的连接角 产生变化的轮子半径dynr平均扭转力矩损失T当每个装置的转向扭转力以及轮子之间的转向装置扭转力不同时，将围绕着主销轴线变动，如下所示：2cosMAcosT 22(tan/2/sin)(tan/2/tan)vvw hivvw liTTTT这里 转向装置扭转力矩差T W轮子一侧的下标因此很明显不仅不同的驱动扭转力而且黏性驱动轴长度的不同也是一个因素。说道图 7 中的力矩多边形，的旋转方向或者各自地变化，都取决于2MT轮子中心到变速箱输出的位置。如图 7 所示由于半轴的正常位置（轮子中心低于变速箱的输出点）第二个力矩产生和驱动力一样的旋转方向。由于改进的悬挂装置设计（车轮中心高于变速箱输出点，也就是说，为负值）第二个力矩抵消了由驱动力引起的力矩。v这样为了得到带一个限制滑动差速器前轴好的适应性，设计要求：1）纵向弯曲角近似或者负值（）且左侧和右侧的值相等；2）等长度的侧轴。0v0vv第二力矩在转向装置的影响不仅仅是上面描述的限制直接反应。从连接轴17到车轮侧面和变速箱侧面之间的连接点间接反应也会产生，如下所示：图表 9：由纵向平面的半轴连接产生的间接反应因为扭转力传递没有损失并且两个在连接轴上的第二个力矩都相vwvd互补偿。然而，事实上（有扭转力损失） ，第二个力矩出现不同： 21DWDWMMM 22DWTTT第二个力矩不同点是：22()tan/2/sintan/2/tanDWWWVDWvwWvwMTTTTT为了简化应用给出和fTVDVWVDTT wT(tan/2 1/sin1/tan)DWvvvMTA需要在两个连接处都有抵抗反应的力这里DWM。由连接处引起的干扰常数 f，一个附加的转向装置扭转力矩/DWDWFML 也围绕着主销轴线变动： cos/fDWTMfL A A这里 每个车轮的转向装置扭转力矩fT 转向装置扭转力矩差fT f连接处干扰系数 L连接轴（半轴）的长度由于 f 值小，理想值是 0，的影响较小。fT5 转弯时的效应扭转时由于驱动轮的速度不相等，黏性连接器也提供一个自琐的扭转力矩。如图表 10 所示，在平稳转向过程中，速度较慢的内侧车轮被外侧车轮黏性连接器施加的一个附加的驱动力。如图表 10：前轮驱动力的汽车稳定状态下转向时的牵引力。18不同的牵引力和导致一个侧偏力矩 MCOG，它必须被一个较大的flDfrDflD侧偏力补偿，因此在前轴有一个大的滑动角 af。因此前驱动轮的汽车自动转向装置上黏性连接器的影响趋向一个在转向装置状态下的特性。这个运动方式整体上和所有转向操纵下在稳定状态下转弯移动时的现代汽车操纵方式的偏重心相一致.合适的试验结果如图表 11 所示。如图表 11：安装有开式差速器的汽车饿安装有黏性连接器的汽车在稳定状态下转弯时的对比如图表 10 所示在转弯时不对称的牵引力干扰也会改进汽车的直线行驶。每一次偏离正常的直线方向都会引起车轮以轻微的不同半径滚动。驱动力和产生的侧偏力矩差会使汽车重新回到直线行驶（如图表 10） 。虽然这些方向的偏离引起仅仅很小的车轮滚动半径差，但是旋转的偏差尤其在高速时对于一个黏性连接器前差速器是足够将汽车带到直线上行驶的。安装有开式差速器的高动力前轮驱动汽车当以低档加速离开紧急转角时通常旋转它们的内侧车轮。安装有限制滑动黏性差速器，这个旋转是有限的并且有不同车轮的速度差产生的扭转力为外侧的驱动轮提供附加的牵引力效果。这显示在图表 12 中。如图表 12：装有黏性限制滑动差速器的前轮驱动汽车在转道上加速时的牵引力特别地当行驶或加速离开一个 T 形交叉路口加速能力就这样被改善（也就是说在 T 形路口横切向右或向左从停止位置加速） 。图表 13 和 14 显示了装有开式差速器和装有黏性限制滑动差速器在稳定状态下转弯过程中加速试验的结果。如图表 13 所示：装有一个开式差速器的前轮驱动汽车在半径为 40m 的湿沥青弯曲路面上加速特性（实验过程中安装有转向装置轮角测试仪）如图表 14 所示：装有一个黏性连接器的前轮驱动汽车在半径为 40m 的湿沥青弯曲路面上加速特性（实验过程中安装有转向装置轮角测试仪）安装有一个开式差速器的汽车平均加速度为同时装有黏性连CSDM22.0/m s接器的汽车平均加速度达到（被发动机功率限制） 。在这些试验中，由22.3/m s19内侧的从动轮引起的最大速度差，被从带有开式
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