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动力传动圆锥渐开线齿轮的设计、制造和应用Dr.J.Borner,K.Humm,Dr.F.Joachim,Dr.H.akaria,ZF Friedrichshafen AG,88038Friedrichshafen,Germany;摘要圆锥渐开线齿轮(斜面体齿轮)被用于交叉或倾斜轴变速器和平行轴自由侧隙变速器中。圆锥齿轮是在齿宽横断面上具有不同齿顶高修正(齿厚)的直齿或斜齿圆柱齿轮。这类齿轮的集合形状是已知的,但应用在动力传动上则多少是个例外。ZF公司已将该斜面体齿轮装置应用于各种场合:4W D轿车传动装置、船用变速器(主要用于快艇)机器人齿轮箱和工业传动等领域。斜面体齿轮的模数在0.7mm-8mm之间,交叉传动角0-25之间。这些边界条件需要对斜面体齿轮的设计、制造和质量有一个深入的理解。在锥齿轮传动中为获得高承载能力和低噪音所必须进行的齿侧修形课采用范成法磨削工艺制造。为降低制造成本,机床设定和由于磨削加工造成的齿侧偏差可在设计阶段利用仿真制造进行计算。本文从总体上介绍了动力传动变速器斜面体齿轮的研发,包括:基本几何形状、宏观及微观几何形状的设计、仿真、制造、齿轮测量和试验。1 前言在变速器中如果各轴轴线不平行的话。转矩传递课采用多种设计,例如:伞齿轮或冠齿轮、万向节轴或圆锥渐开线齿轮(斜面体齿轮)。圆锥渐开线齿轮特别适用于小轴线角度(小于15),该齿轮的优点是在制造、结构、特点和输入多样性等方面的简易。圆锥渐开线齿轮被用于直角或交叉轴传动的变速器或被用于平行轴自由侧隙工况的变速器。由于锥角的选择并不取决于轴线交角,配对的齿轮也可能采用圆柱齿轮。斜面体齿轮可制成外啮合和内啮合齿轮,整个可选齿轮副矩阵见表1,它为设计者提供了高度的灵活性。圆锥齿轮是在齿宽横截面上具有不同齿顶高修正(齿厚)量的直齿或斜齿轮。它们能与各种用同一把基准齿条刀具切制成的齿轮相啮合。斜面体齿轮的集合形状是已知的,但它们能与各种用同一把基准齿条刀具切制成的齿轮相啮合。斜面体齿轮的几何形状是已知的,但它们很少应用在动力传动上。过去,未曾对斜面体齿轮的承载能力和噪声进行过任何大范围的试验研究。标准(诸如适用于圆柱齿轮的ISO06336)、计算方法和强度值都是未知的。因此,必须开发计算方法、获得承载能力数值和算出用于生产和质量保证的规范。在过去的15年中,ZF公司已为锥齿轮开发了多种应用:1、 输出轴具有下倾角的船用变速1、3图.12.转向器13、机器人用小齿隙行星齿轮装置(交叉轴角度13)24、用车辆的输送齿轮箱(垃圾倾倒车)5、AWD用自动变速箱4,图22齿轮几何形状2.1宏观几何形状简而言之,斜面体齿轮可看成是一个在齿宽横截面上连续改变齿顶高修正的圆柱齿轮,如图3.为此,根据齿根锥角刀具向齿轮轴线倾斜1。结果形成了齿轮基圆尺寸。螺旋角,左/右 (1)横向压力角 左/右 (2)基圆直径 左右 (3)左右侧不同的基圆导致斜齿轮齿廓形状的不均匀,图3.采用齿条类刀具加工将使得齿根锥具有相应的根锥角。齿顶角设计成这样以使得顶端避免与被啮合齿轮发生干涉,并获得最大接触区域。由此导致在齿宽横截面上具有不同的齿高。由于几何设计限制了根切和齿顶形状,实际齿宽随锥角增加而减小,锥齿轮传动合适的锥角最大=约为15。2.2微观几何形状一对伞齿轮通常形成点状接触。除接触外,在齿侧还存在间隙,如图7.齿轮修行设计的目的是减小这些间隙以形成平坦二均匀的接触。通过逐步应用啮合定律有可能对齿侧进行精确的计算5,图4.最后,在原始侧生成半径为rp1和法向矢量为n1的P1点。这生成速度矢量VP1 及对于在啮合一侧所生的点,有半径矢量rp2:3传动装置设计3.1根切和齿顶形状斜面体齿轮的可用齿宽受到大端齿顶形状和小端根切的限制,见图3.齿高越高(为获得较大的齿高变位量)理论可用齿宽越窄。小端根切和大端齿顶形状导致齿高变位量沿齿宽方向发生变化。当一对齿轮的锥角大致相同时可获得最大的可用齿宽。若齿轮副中小齿轮愈小,则该小齿轮必须采用更小的锥角。齿顶锥角小于齿根锥角时,通常能在小端获得有用的渐开线,而在大端处有足够齿顶间隙,这时大端的齿顶形状并不太严重。3.2工作区域和滑动速度斜面体齿轮工作区域产生扭歪的原因是圆锥半径有形成平行四边形趋势。另外,工作压力角在齿宽横截面方向的改变也造成工作区域的扭曲。图5是一个例子。在交叉轴传动的斜面体齿轮上存在一滚动轴;如同圆柱齿轮副的滚动点一样,在该轴上不存在滑动。对于倾斜轴布置而言,在轮齿啮合处总存在另外的轴向滑动。由于工作压力角在齿宽横截面上变化,从小端到大端的接触区内的接触轨迹有很大的变化。因此,沿齿宽方向在齿顶和齿根处具有明显不同的滑动速度。在齿轮中部,齿顶高修正的选择是基于圆柱齿轮副的规范;在主动齿轮根部的接触轨迹将小于齿顶的接触轨迹。图6给出了斜面体齿轮副主动齿轮滑动速度的分布。4接触分析和修形4.1点接触和间隙在未修正齿轮传动中,由于轴线倾斜,通常仅有一点接触。沿可能接触线出现的间隙可大致解释为螺旋凸起和齿侧廓线角度的偏差所致。圆柱齿轮左右侧间隙与轴线交叉无关。对于螺旋齿轮而言,当两斜面体齿轮锥角大致相同时,其产生的间隙也几乎相等。随两齿轮锥角和螺旋角不一致的增加,左右侧间隙的不同程度也增加。在工作压力角较小时将导致更大的间隙。图7给出了具体相同锥角交叉轴传动的斜面体齿轮副所出现的间隙。图8显示了具体相同10交叉轴线和30螺旋角齿轮在左右侧间隙方面的差异。两侧平均间隙的数值在很大程度上与螺旋角无关,但与两齿轮的锥角相关。螺旋角和锥角的选择决定了齿轮左右侧平均间隙的分布。倾斜轴线布置对接触间隙产生额外影响。这将有效减少齿轮一侧的螺旋凸形。如果垂直轴线与总基圆半径相同,并且基圆柱螺旋角之差等于交叉轴角的话,间隙减少到零并出现线接触。然而,在另一侧将出现明显的间隙。如果正交的轴线进一步扩大直至变成圆柱交叉轴螺旋齿轮副的话,其两侧间隙等同于较小的螺旋凸形。除螺旋凸形外,明显的齿廓扭曲(见图8)也是斜面体齿轮的间隙特征。随螺旋角增加齿廓扭曲也随之增加。图9表明图7所示齿轮装置的齿廓是如何扭曲。为补偿齿轮啮合中所存在的间隙,必须采用齿侧拓扑修行,该类修形可明显补偿螺旋凸形和轮廓扭曲。未对齿廓扭曲作补偿的话,在工作区域仅有一个对角线状的接触带,见图10.4.2齿侧修形对于一定程度的补偿而言,必需的齿面形状可由实际间隙所决定。图11给出了这些样品的齿形几何特征。采用修正后的接触率得到了很大改善如图12所示。为应用在系列生产中,其目标总是能使用磨床加工这类齿面,对此的选择在第6节论述。除间隙补偿外,齿顶修形也是有益的。修形减少了啮合开始和结束阶段负荷,并能提供一较低的噪声激励源。然而,斜面体齿轮的齿顶修形在齿宽横截面上的加工总量和长度上是不同的。问题主要出现在具有一个大根锥角但顶锥角与根锥角存在偏差的齿轮上。因此齿顶修形在小端明显大于大端。如齿轮需要在啮合开始和结束处修形,则必须接受这种不均匀的齿顶修形。利用其它锥角如根锥角进行齿顶修形加工也是可以的。但是,这样需要专门用于齿顶卸载的专用磨削设备。与范成法磨削方法无关,齿侧修正可采用诸如珩磨等手段;但在斜面体齿轮上应用这些方法尚处在早起开发阶段。5承载能力和噪声激励5.1计算标准的应用斜面体齿轮齿侧和根部承载能力仅可用圆柱齿轮的计算标准(ISO 6336,DIN 3990,AGMAC95)作近似估算。具体计算时用圆柱齿轮副替代斜面体齿轮,用斜面体齿轮中部的齿宽来定义圆柱齿轮的参数。虽然斜面体齿轮齿宽是非对称的,但在替代齿轮中可不予考虑。替代齿轮中心距由斜面体齿轮中部齿宽处的工作节圆半径确定。当计及齿宽横截面时,各项独立的参数都会变化,这将明显影响承载能力。表2给出了影响齿根和齿侧承载能力的主要因素。由于沿大端方向减少轮齿齿根圆角半径所产生较大的凹口效应阻止了根部齿厚的增加。另外,在大端处,较大的节圆直径可获得较小的切向力;然而,大端处的齿高变位量也随之变小。由于主要影响得到很好的平衡,因此可用替代齿轮副获得十分近似的承载能力计算结果。齿宽横截面上的载荷分布可用齿宽系数(例如DIN/ISO标准中的)表示和利用补充的负载曲线图分析来确定。5.2轮齿接触分析如图在圆柱齿轮副中那样,更精确的承载能力计算可采用三维轮齿接触分析。同样采用替代齿轮,而且齿侧处接触状况被认为非常理想。该齿侧形状通过叠加经齿侧修正的无负载接触间隙而获得。在这里,接触线由替代齿轮所确定,它们和斜面体齿轮的接触状况稍有不同。图13给出了以这方法获得的载荷分布,并与已有的负载曲线图作对比,两者的相关性非常好。轮齿接触分析也将生成一个作为激振源的由轮齿啮合产生的传动误差。然而这仅能作为一个粗略的引导。在传动误差方面,斜面体齿轮接触计算的不精确性是一个比载荷分布更大的影响因素。5.3采用有限元法的精确建模斜面体齿轮的应力也能利用有限元法计算。图14是齿轮横截面建模的实例。图15给出了使用PERMAS软件由计算机生产的主动齿轮在啮合位置的轮齿啮合区模型和应力分布计算值.可对多个啮合位置进行计算,并能求出齿轮旋装产生的传动误差。5.4承载能力和噪声试验在交叉轴背靠背试验台上对AWD变速器进行试验以测量其承载能力,图16。试验齿轮采用不同的修正,以确定它们对承载能力的影响。承载能力的试验与有限元计算结果相当吻合。值得注意的是,由于大端硬度提高使得载荷曲线图朝大端由一个额外的移动。这种移动在替代的圆柱齿轮副计算中不能被辨别。在进行承载能力试验的同时,传动误差和旋转加速度的测量在通用噪声试验台上进行,图17。除了载荷影响外,这些试验还要测量了附加轴线倾斜所引起的噪声激励,关于轴线附加倾斜,试验中未发现有明显的影响。6仿真制造借助于仿真制造,可获得机床设置及连续范成磨削和产生齿廓扭曲的运动。齿廓瘦迫扭曲现象可在变速器设计阶段就被认识到并与承载能力及噪声一并进行分析。斜面体齿轮制造仿真软件由ZF公司开发,详见9。6.1适用于斜面体齿轮的制造方法斜面体齿轮仅可用范成法加工,因为齿宽形状沿齿宽方向有明显的变化。尽管是锥角非常小的斜面体齿轮,必须承认在修整处理中任然会出现齿宽角度偏差。滚刀最方便用于预切削。理论上也可采用刨削,但是,所需的运动在现有机床上很难实现。内齿圆锥齿轮仅能用类似小齿轮的刀具精确制造,如果刀具轴线和和工具轴线平行并且锥角是通过改变中心距生成的。如果内齿轮利用轴线倾斜的小齿轮刀具如同加工差速器锥齿轮那样来制造的话,将导致齿沟凸起和修正运动的齿廓扭曲。对于小锥角而言这些偏差足够小,可以被忽略。对于终加工,范成法螺旋磨削是一个最佳选择。如果工件或机床夹具能被另外倾斜,可可以采用部分范成法。如果齿轮锥角处于机床控制范围内,拓扑磨削工艺也是可能的(例如5轴机床),但是会消耗巨大的努力。原则上,珩磨等方法也能被用于加工,但是,在斜面体齿轮应用这些方法任需大量的开发工作。双齿侧范成法磨削工艺并利用中心距弧形减少方法可实现齿沟凸起的目标。该方法所得到的齿廓扭曲与造成啮合间隙的齿廓扭曲相反。因此该方法可在很大程度上补偿齿廓扭曲并可承受比圆柱齿轮更大的载荷。6.2工作表面形状以下关于工作描述被应用在仿真中:原始齿轮(留有磨削所需的余量)理想齿轮(来自齿轮数据,无齿侧修形)完成的齿轮(具有制造偏差和齿侧修形)参考文献1.J. 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Application, Design, and Manufacturing of Conical Involute Gears for Power TransmissionsDr. J. Borner, K. Humm, Dr. F. Joachim, Dr. H. Yakaria,ZF Friedrichshafen AG , 88038Friedrichshafen, Germany:ABSTRACT Conical involute gears (beveloids) are used in transmissions with intersecting or skew axes and for backlash-free transmissions with parallel axes. Conical gears are spur or helical gears with variable addendum modification ( tooth thickness ) across the face width. The gecometry of such gears is generally known, but applications in power transmissions are more or less exceptional. ZF has implemented beveloid gear sets in varioue applications: 4WD gear units for passenger cars, marine transmissions ( mostly used in yachts ), gear boxes for robotics, and indusrtial drives. The module of these beveloids varies between 0.7 mm and 8 mm in size, and the crossed axes angle varies between 0and 250. These boundary conditions require a deep understanding of the design, manufacturing, and quality assurance of beveloid gears. Flank modifications, which are necessary for achieving a high load capacity and a low noise emission in the conical gears, can be produced with the continuous generation grinding process. In order to reduce the manufacturing costs, the machine settings as well as the flank deviations caused by the grinding process can be calculated in the design phase using a manufacturing simulation. This presentation gives an overview of the development of conical gears for power transmissions: Basic geometry, design of macro and micro geometry, simulation, manufacturing, gear measurement,and testing.1 IntroductionIn transmissions with shafts that are not arranged parallel to the axis, torque transmission is P ossible by means of various designs such as bevel or crown gears , universal shafts , or conical involute gears (beveloids ). The use of conical involute gears is particularly ideal for small shaft angles ( less than 15), as they offer benefits with regard to ease of production, design features, and overall input. Conical involute gaars can be used in transmissions with intersecting or overall input. Conical involute gears can be uese in transimissions with intersecting or skew axes or in transmissions with parallel axes for backlash-free operation. Due to the fact that selection of the cone angle does not depend on the crossed axes angle, pairing is also possible with cylindrical gears. As beveloids can be produced as external and internal gears, a whole matrix of pairing options results and the designer is provided with a high degree of flexibility;Table 1.Conical gears are spur or helical gears with variable addendum correction ( tooth thickness ) Across the face width. They can mesh with all gears made with a tool with the same basic rack. The geometry of beveloids is generally known, but they have so far rarele been used in power transmissions. Neither the load capacity nor the noise behavior of beveloids has been examined to any great extent in the past. Standards ( such as ISO 6336 for cylindrical gears ), calculation methods, and strength values are not available. Therefore, it was necessary to develop the calculation method , obtain the load capacity values, and calculate specifications for production and quality assurance. In the last 15 years, ZF has developed various applications with conical gears:Marine transmissions with down-angle output shafts /1, 3/, Fig. 1Steering transmissions /1/Low-backlash planetary gears ( crossed axes angle 13) for robots /2/Transfer gears for commercial vehicles ( dumper)Automatic car transmissions for AWD /4/, Fig. 22 GEAR GEOMETRY2.1 MACRO GEOMETRY To put it simply, a beveloid is a spur gear with continuously changing addendum modification across the face width, as shown in Fig. 3. To accomplish this, the tool is tilted towards the gear axis by the root cone angle? /1/. This result s in the basic gear dimensions:Helix angle, right/left(1) Transverse pressure angle right/left(2) Base circle diameter right/left(3) The differing base circles for the left and right flanks lead to asymmertrical tooth profiles at helical gears, Fig. 3. Manufacturing with a rack- type cutter results in a tooth root cone with root cone angle q. The addendum angle is designed so that tip edge interferences with the mating gear are avoided and a maximally large tooth height results across the face width. Due to the geometric design limits r for undercut and tip formation, the possible face width decreases as the cone angle increase. Sufficiently well-proportioned gearing is possible up to a cone angle of approx.15.2.2 MCRO GEOMETRYThe pairing of two conical gears generally leads to a point-shaped tooth contact. Out-side this contact. Out-side this contact, there is gaping between the tooth flanks, Fig. 7. The goal of the gearing correction design is to reduce this gaping in order to create a flat and uniform contact. An exact calculation of the tooth flank is possible with the step-by-step application of the gearing law /5/, Fig. 4. To that end, a point (p) with the radiusrpland normal vectornlis generated on the original lank. This generates the speed vector V with (4) For the point created on the mating flank, the radial vecor rp:(5) And the speed vector apply(6) The angular velocities are generated form the gear ratio:(7) The angle Y is iterated until the gearing law in the form (8) Is fulfilled. The meshing point Pa found is then rotated through the angle (9) Around the gear axis, and this results in the conjugate flank point3 GEARING DESIGN3.1 UNDERCUT AND FORMTIONThe usable face with on he beveloid gearing is limited by tip formation on the heel and undercut on the toe as shown in Fig. 3. The greater the selected tooth height (in the order to obtain a larger addendum modification), the smaller the theoretically useable face width is .Undercut on the toe and tip formation on the heel result form changing the addendum modification along the face width. The maximum usable face width is achieved when the cone angle on both gears of the pairing is selected to be approximately the same size . With pairs having a significantly pinion , a smaller cone angle must be used on this pinion. Top formation on the heel is less critical if the tip cone angle is smaller than the root cone angle , which often provides good use of the available involute on the toe and for sufficient tip clearance in the heel.3.2 FIELD OF ACTION AND SLIDING VELOCITYThe field of action for the beveloid gearing is distorted by the radial conicity with a tendency towards conicity with a tendency towards the shape of a parallelogram. In addition the field of action is twisted due to the working pressure angle change across the face width . Fig. 5 shows an example of this. There is a roll axis on the beveloid gearing with crossed axes; there is on no sliding on this axis as there is on the roll point of cylindrical gear pairs. With a skewed axis arrangement , there is always yet another axial slide in the tooth engagement. Due to the working pressure angle that changes across the face width, there is varying distribution of the contact path to the tip and root contact. Thus , significantly differing sliding velocities can result on the tooth tip and the tooth root along the face width . In the center section , the selection of the addendum modification should be based on the specifications for the cylindrical gear pairs; the root contact path at the diver should be smaller than the tip contact path. Fig. 6 shows the distribution of the sliding velocity of a beveloid gear pair .4 CONTACT ANALYSIS AND MODIFYCATIONS4.1 POINT CONTACT AND EASE-OFFAt the uncorrected gearing , there is only one in contact due to the tilting of the axes. The gaping that results along the potential contact line can be approximately described by helix crowing and flank line angle deviation. Crossed axes result in no difference between the gaps on the left and right flanks on spur gears . With helical gearing, the resulting gaping is almost equivalent when both beveloid gears show approximately the same cone angle.The differentce between the gap values on the left and right flanks increase. This process results in larger gap values on the flank with the smaller working pressure angle. Fig.7 shows the resulting gaping (ease-off) for a beveloid gear pair with crossed axes and beveloid gears with an identical cone angle. Fig.8 shouws the differences in the gaping that results for the left and right flanks for the same crossed axes angle of 10and a helical angle of approx.30. The mean gaping obtained from both flanks is ,to a largr extent, independent of the helix angle and the distribution of the cone angle to both gears.The selection of the helical and cone angles only determines the distribution of the mean gaping to the left and right flanks. A skewed axis arrangement results in additional influence on the contact gaping. There is a significant reduction in the effective helix crowning on one flank. If the axis perpendicular is identical to the total of the base radii and the difference in the base helix angle is equivaklent to the crossed axes angle, then the gaping decreases to zero and line contact appears. However, significant gaping remains on the opposite flank. If the axis perpendicular is further enlarged up to the point at which a cylindrical crossed helical gear pair is obtained, this results in equivalent minor helix crowning in the ease-off on both flanks. In addition to helix crowning, a notable profile twist(see Fig.8) is also characteristic of the ease-off helical beveloids. This profile twist grows significantly as the helix angle increases. Fig.9 shows how the profile twist on the example gear set fron Fig.7 is changed depending on the helix angle. In order to compensate for the existing gaping in the tooth engagement, topological flank corrections are necessary; these corrections greatly compensation of the profil twist, only a diagonally patterned contact strip is obtained in the field of action, as shown in Fig.10.4.2 FLANK MODIFICATIONS For a given degree of compensation, the necessary topography can be determined from the existing ease-off.Fig.11 shows these types of typographies, which were produced on prototypes. The contact rations have improved greatly with these corrections as can be seen in Fig.12. For use in series production, the targer is always to manufacture such topographies on commonly used grinding machines. The target is always to manufacture such topographies on commonly used grinding machines. The options for this are described in section 6. In addition to the gaping compensation , tip relief is also benefical. Thid reduces the load at the start and at the end of meshing and can also provide lower noise excitation. However, tip relief manufactured at beveloid gears is not constant in amount and length across the face width. The problem primarily occurs on gearing with a largr root cone angle and a tip cone angle deviating from this angle .The tip relief at the toe is significantly larger than at the heel. This uneven tip relief must be accepted if relief of the start and end of meshing is required. The production of tip relief using another cone angle as the root cone angle is possible; however , this requires an additional grinding step onle for the tip relief . Independently of the generating grinding process, targeted flank topograpjy can be manufactured by coroning or honing ; the application of this method on beveloids , however, is still in the early stages of development.5 LOAD APACITY AND NOISE EXCITATION5.1 APPLICATION OF THE CALCULATION STANDARDAThe flank and root load capacity of beveeloid gearing can onle approximately be deter-mined using the calculation standards (ISO6336, DIN3990,AGMA C95) for cylindrical gearing. A substitute cylindrical gear pair has to be used ,which is defined by the gear parameners at the center of the face width. The profile of the beveloid tooth is asymmetrical; that can , however, be ignored on the substitute gears. The substitute center distance is obtained by adding up the operating pitch radii at the center of the face width. When viewed across the face width, individual parameters will change , which significantly influence the load capacity. Table 2 shows the main influences on the root and flank load capacities. The large notch effect due to the decrease in the tooth root fillet radius towards the heel is in opposition to the increase in the root thickness .In addition, there is a smaller tangential force on the larger operating pitch circle at the heel; at the same time, however, the addendum modification on the heel is smaller. The primary influences are nearly well-balanced so that the load capacity can be calculated sufficiently approximate with the substitute gear pair . The load distribution across the face width can be considered with the width factors (e. g. k. and k. in DIN/ISIO) and should be determined from additional load pattern analyses.5.2 USE OF THE TOOTH CONTACT ANALYSISA more precise calculation of the load capacity is possible with a three-dimensional tooth contact analysis , as used at cylindrical gear pair can be used in this analysis and the contact conditions are considered from the supermposition of of the load-free contact ease-off with the flank corrections used on the gear. In this process, the contact lines are determined on the substitute cylindrical gear and they differ slightly from the contact at the beveloid gear. Fig. 13 shows the load distributions calculated in this manner as compared to the load patterns recorded , and a very goodcorrelation can be seen.This tooth contact analysis also generates the tansmission error resulting from the tooth mesh as vibrational excitation. It can, however, only be used as a rough guide . The impreciseness in the contact behavior calculated has a stronger effect on the transmission error than it douse on the load distribution.5.3EXACT MODELING USING THE FINTE-ELEMENT METHODThe stress at the beveloid gears cab also be calculated using the finite-element method .Fig. 14 shows examples of the modeling of the transverse section on the gears. Fig. 15 shows the computer-generated model in the tooth mesh section and the stress distribution calculated with PERMAS/7/ on the driven gear in a mesh position. The multiple mesh positions and the transmission error can be determined from the rotation of the gears.5.4 TESTS REGARDING LOAD CAPACITY AND NOISEA back-to-back test bench with crossed axes, upon which gear pairs from AWD transmissions were tested, was used to determine the load capacity ,Fig.16. Different corrections were produced on the test geasrs in order to ascertain their influence on the load capacity. There was good correlation between the load capacity in the test and the FE results. Particularly stiffness in this area. This shift is not discernable in the calculation with the substitute cylindrical gear pair. Simultaneous to the load capacity tests, measurements of the transmission error and rotational acceleration were conducted in a universal noise test box, Fig . 17. In additional to the load influence, the influence of additional axis tilt on the noise excitation was also esamied in thse teasts .With regard to this axis tilt, no large amount of sensitivity in the tested gear sets was found .6 MANUFACTURRIBF SIMULATIONWith the assistance of the manufacturing simulation, machine settings and movemengts with continuous generation grinding as well as the produced profile twist can be obtained . Production-constrained profile twist can be considered as early as the design phase of a transmission and can be incorporated into the load capacity and noise analyses. Simulation software for the manufacturing of beveloids was specially developed at ZF, which is comparable to /9/.6.1 PRODUCTION METHODS THAT CAB VW USED BEVELOIDSOnly generating methods can be used to produce the beveloid gearing, because the shape of the tooth profile changes significantly along the face width. Only very slightly conical bevelodis can be manufactured with the acknowledgment that there is profile angle deviation even with the shaping process. Hobs are the easiest to use for pre-cutting. G ear planning would theoretically be useable as well; however , the kinermatics required makes this not really feasible on sxisting machines. Internal conical gears can then only be precisely manufactured with pionion-type cutter axis is parallel to the tool axis and the cone is created by changing the center distance. If the internal gear is manufactured with a tilled pinion cutter without corrective movements. Theses deviations are small enough to be ignored for minor cone angles . For final processing , contiuous generation grinding with a grinding worm appears to be the best option. If the workpise or tool fixture can be additionally tilled ,then partial generation methods are also applicable . Processing in a topological grinding process is also possible (e. g. 5-axis machines ), but with great effort , when the cone angle of the gearing can be considered in the machine control. In principle , honing and coroning can also be used for the processing; however, the application of these methods in beveloids still needs extensive development. The targeted hollow crowing can be created in the generation grinding process in the dual-flank grinding process via a bowshaped reduction in the center distance . Thid method results in a profile twist , that is the reverse of the profile twist from the contact gaping. Thus , tisi method provides extensive compensation for the profile twist and a significantly more voluminous load pattern as is typical on cylindrical gears.6.2 WORKPIECE GEOMETRY The following workpiece descriptions are used in the simulation:Initial gear ( with stock allowance for the grind processing)Ideal gear (from the gear data , without flank corrections )Finished gear ( with production-constrained deviations and flank corrections) 参考文献1.J. A. macbain, J. J. Conover, and A. D. brooker,“Full-vehicle simulation for series hybrid vehicles,” presented at SAE Tech. paper, Future Transportation technology Conf., Costa Mesa, CA,jun.2003, Paper2003-01-2301.2.X.Heand I. Hodgson, “Hybrid electric vehicle simulation and evaluation for UT-HEV,”pemented at the SAE Tech. Paper Series,Future Transpotation Technology Cong., Costa Mesa, CA,Aug,2000,Paper 2000-01-3105.3.K.E.Bailey and B. K. Powell, “ A hybira electric vehicle powertrain dynamic model,”in proc.Amer. 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