弧齿锥齿轮的齿面主动设计

齿面印痕和传动误差对齿轮传动的性能起着决定作用,针对齿面印痕和传动误差,提出弧齿锥齿轮点啮合齿面主动设计的方法。该方法突破了传统齿轮设计的局限性,采用“局部共轭原理”和“局部综合法”,并依据弧齿锥齿轮的加工原理,使齿轮设计人员能够按照要求的传动性能来设计齿面的形状,并可在摇台结构的铣齿机进行加工。齿面主动设计能保证齿面在整个啮合过程中满足预先设计的传动误差和齿面接触路径的要求,从而达到对齿面啮合质量的全程控制,它为弧齿锥齿轮副设计提供新的方法和途径,这对于高速和重载齿轮以及有特殊要求的齿轮的设计具有十分重要的意义。     

高齿准双曲面齿轮的研究

研究基于局部综合法的高齿准双曲面齿轮ＨＦＴ法切齿参数的设计,给出用ＨＦＴ法加工准双曲面齿轮副的齿面接触分析方法,并在此基础上,比较了普通齿和高齿２种准双曲面齿轮副的传动误差曲线和啮合区。结果表明,高齿准双曲面齿轮副具有较好的啮合性能。     

一种弧齿锥齿轮安装误差变动范围的确定方法

提出一种接触印痕位置参数分析法,用于确定弧齿锥齿轮安装误差的可变动范围。根据设计要求的啮合性能,采用局部综合法,设计弧齿锥齿轮加工参数,得到弧齿锥齿轮副齿面。在齿面参考点处的压入深度为0.006 35 mm的条件下,计算小轮驱动力矩。在此力矩作用下,进行安装误差状态下的轮齿加载接触分析(Loaded tooth contact analysis,LTCA),获得描述承载齿面接触印痕的位置参数。以接触印痕边界点到齿面边界的距离为设计目标,分别以不同类型的单因素安装误差为设计变量,采用优化设计方法确定接触印痕在齿面有效边界内变动时,对应的安装误差的变动范围。以某航空发动机附件传动系统中的弧齿锥齿轮为对象,依据上述方法,确定出不同类型安装误差的可变动范围,验证上述方法的有效性。所提出的方法为合理确定弧齿锥齿轮副安装误差的变动范围提供一种参考。     

Geometric design of involute spur gear drives with symmetric and asymmetric teeth using the Realized Potential Method

The index gear drive potential is defined for the estimation of the quality of spur gear drives as a maximum contact ratio obtained at the contact of teeth profiles along the full line of action. In this paper, a new method is proposed for the geometric design of symmetric and asymmetric involute meshing in which the contact ratio of the gear drive is equal to its potential. This method is appropriate for the geometric design of spur gears with a small teeth number and is based on the generalized model of involute meshing. The gear drive potential is assigned as an input value, from which, after appropriate calculations, the geometry of rack-cutters, gears and involute meshing can be determined. Using the proposed method, the areas of the realized potential and the areas of the existence of involute gear drives are defined. In addition, many numerical examples are solved. In the cases of symmetric and asymmetric meshing, the minimum teeth number is obtained when the gear drive potential is larger than one.     

Geometry design and tooth contact analysis of crossed beveloid gears for marine transmissions

Beveloid gears,also known as conical gears,gain more and more importance in industry practice due to their abilities for power transmission between parallel,intersected and crossed axis.However,this ty...     

相交轴渐开线变厚齿轮几何设计与啮合特性分析

根据空间齿轮啮合原理,建立相交轴渐开线变厚齿轮传动工作节圆锥模型,确定工作节锥角、齿线倾斜角及两齿轮安装距。提出空间点接触到线接触的转变控制条件,实现相交轴齿轮副的近似线接触;推导齿轮变位系数对节圆锥左右两侧有效齿宽的影响;基于相交轴变厚齿轮副参数关系,分析设计参数对啮合主方向角(FPD角)和齿轮副重合度的影响;根据线接触控制条件完成齿轮副参数设计并采用有限元法进行啮合特性分析,结果表明,考虑线接触条件的节圆锥设计得到的相交轴齿轮副在加载情况下,啮合状态呈现明显的线接触且啮合区域达到整个区域的50%左右,试验验证了理论分析的正确性。     

Simulation of meshing for the spur gear drive with modified tooth surfaces

The authors have proposed methods (lead crowning and profile modification) for modifying the geometry of spur gears and investigated the contact pattern as well as the transmission errors to recommend the appropriate amount of modification. Based on the investigation, dynamic load of the modified spur gear drive has been calculated, which is helpful to predict the life of the designed gear drive. Computer programs for simulation of meshing, contact and dynamics of the modified spur gears have been developed. The developed theory is illustrated with numerical examples.     

具有最佳加载接触性能的弧齿锥齿轮主动设计研究

基于局部综合理论的弧齿锥齿轮齿面接触分析(TCA )和接触性能预控技术可保证弧齿锥齿轮在无载时具有较理想的接触区域和传动误差 ,但无法保证其加载接触性能。本文在柔性多体运动学基础上 ,建立了两弹性共轭齿面运动基本方程。将啮合点弹性变形分解为支承变形、轮体变形和接触变形 ,获得了变形前后齿面几何量的变化规律以及两弹性点共轭齿面间的接触条件。提出了一种在初始设计阶段就可保证弧齿锥齿轮具有预期加载接触性能的主动设计方法 ,并将其用于某航空发动机中央传动弧齿锥齿轮的齿面综合     

某无人直升机主传动齿轮啮合强度分析

基于ANSYS分析软件,采用接触单元,对某无人直升机主传动齿轮副的啮合过程进行数值模拟,直观得到了啮合过程中齿轮副上的瞬态应力,并对该齿轮副进行疲劳计算,预估其寿命,从而为该齿轮安全工作和优化设计提供理论依据。这种基于ANSYS的齿轮啮合强度分析方法可为其它齿轮啮合疲劳传动分析提供借鉴。     

准双曲面齿轮齿面接触应力过程计算

针对准双曲面齿轮疲劳破坏中出现几率最高的齿面接触疲劳强度问题,在齿面接触分析（TCA）和承载接触分析（LTCA）的基础上,采用弹性力学中2个空间曲面弹性接触计算方法,计算了齿轮副在整个啮合过程中齿面最大接触应力的变化过程,指出了最大接触应力所在的齿面位置,这一点与现有的强度计算方法不同,为实际工程中准双曲面齿轮的接触强度设计与校核提供了更为准确的方法。     

A study on using deviation function method to reshape a rack cutter

In this paper a method for the modified profile of a rack cutter is presented. The deviation function method is used to reshape a rack cutter. The author proposes a modified geometry of a rack cutter to generate the driving gear of internal gear pairs. Based on the double envelope concept, the driven gear of a set of internal gear pairs can be determined. In this study, the Von-Mises stress analysis of the reshaped internal gear pairs was carried out and the specific phenomena was also investigated. The results show that it is possible to compensate elastic deformation and reduce contact stress between conjugate gear pairs. In addition, according to the tooth contact analysis on the gear pairs, reshaped gears and conventional gears have also been investigated. Computerized design of internal gears using the proposed method and simulation of their meshing and contact stress analysis of asymmetric internal gears has been developed. The developed method is illustrated with numerical examples.     

Investigation of the Thermal Behaviour of Non‐metallic Curved‐Face‐Width Spur Gears

This paper describes a curved‐face‐width spur gear, specially designed for manufacture from non‐metallic materials. The benefits of this gear are the higher contact ratio, bending and Hertzian contact resistance, and greater tooth stiffness compared to standard spur gears. A modified geometry is proposed for the gear tooth, the height of which varies along the gear face width. Due to the reduction in tooth height, in sections away from the gear centre, lower sliding friction is expected, with consequences for the gear's thermal behaviour. The complex gear geometry makes the design of a die difficult; therefore the gears were cut on a milling machine, using a special kinematic generation process and related equipment. The tooth flank profile, an involute or near involute in sections away from the gear half‐width plane, as well as the flank surface quality determined by the single‐cutter tool used for gear manufacture, influence the meshing condition, and can be detrimental to the thermal behaviour of the gear. Experimental tests were carried out to examine the influence of load and speed on the temperature of the curved‐face‐width spur gears with modified geometry. The measured temperature of the non‐standard gear is further compared with the predicted temperature of plastic standard spur gears of the same specification.     

弧齿锥齿轮双重螺旋法切齿原理及齿面接触分析研究

弧齿锥齿轮双重螺旋法具有高效、可实现干切削的特点,是Gleason制弧齿锥齿轮的先进加工方法。为揭示双重螺旋法的切齿原理,以大轮成形法加工的弧齿锥齿轮双重螺旋法为研究对象,以啮合原理和微分几何学为基础,根据刀盘、机床、工件之间的运动位置关系,利用矢量法、基于齿面3个参考点建立切齿数学模型,推导机床调整参数的计算过程;然后,以齿槽中点作为参考点,修正弧齿锥齿轮副的齿坯几何参数;另外,以小轮产形面方程代替其共轭齿面方程,提出新的齿面失配设计新方法,与传统方法相比简化计算过程。以一对7×43的准双曲面齿轮副为例进行设计计算和切齿加工,齿面接触分析与滚动检查结果验证所提出的双重螺旋法切齿原理的正确性,并根据该切齿原理开发弧齿锥齿轮双重螺旋法的设计软件,为该方法在国内的推广提供理论基础与技术支撑。     

基于啮合特性直齿锥齿轮分支传动静力学均载分析

为了改善直齿锥齿轮分支传动系统性能,提出基于啮合特性的静态均载分析方法。通过建立考虑中心轮安装误差的单级分支系统多体齿轮齿面接触分析(MTCA)方法,获得各齿轮副初始接触间隙;计及该间隙引起的啮合偏差,采用集中参数法主要考虑中心轮的浮动特性,建立考虑其支撑变形、各齿轮扭转变形相互耦合的静力学平衡方程,获得各分支均载系数,分析了载荷、安装误差、支撑刚度等对系统均载系数的影响。结果表明,随支撑刚度、安装误差的增大,均载系数逐渐增大,轴向对正误差和偏置对正误差对均载系数的影响是等效的;随转矩的增加,均载系数逐渐减小;各分支齿轮副的几何传动误差大小反映了均载系数变化规律,即齿面初始间隙越大,承担的载荷越小。研究结果为高精度直齿锥齿轮分支系统的均载分析提供了理论参考。     

弧齿锥齿轮的齿面主动设计及试验验证

齿面印痕和传动误差对齿轮传动的性能起着决定作用,根据齿面印痕的位置、方向及传动误差幅值的要求,在齿面上设计三个啮合点,通过对这三个啮合点的控制,达到对齿面啮合质量的全程控制。在此基础上,为了满足不同的加工要求,又提出按照给定的垂直轮位的值对齿面进行再设计,保证传动误差的幅值不变且接触迹线仅有较小的改变,为弧齿锥齿轮副设计提供了新的方法和途径。最后在磨齿机上加工了一对齿轮,通过印痕检测验证了本文设计方法的正确性。     

准静态与动态载荷下斜齿轮齿面粘着磨损计算

基于反向圆锥滚子等效接触模型和Archard磨损计算通式,提出了一种适用于标准斜齿轮齿面粘着磨损的计算方法。由时变接触线长百分比和弯-扭-轴耦合动力学模型确定齿面载荷,根据等效接触模型和Hertz接触理论计算齿面压力和滑移距离,求出准静态与动态载荷下的齿面磨损量。通过将主动轮磨损曲线与相关文献结果比较,验证了上述方法的正确性。几何与工作参数对磨损量的影响分析显示,齿根与齿顶处的磨损量较大,且齿根的磨损量大于齿顶,节圆处的磨损量趋近于零;齿轮前端面至后端面,主动轮磨损量逐渐减小而从动轮磨损量逐渐增大;宽齿轮的磨损量沿齿宽渐趋均布。参数分析表明：增大模数、传动比、齿宽或减小扭矩均可降低磨损量,增大螺旋角或改变转速对减小齿面磨损的作用不明显。上述研究对于提高齿轮表面质量与传动性能,对于减磨设计具有一定的参考价值。     

Modeling of helical gear contact with tooth deflection

The majority of gear tribological studies are made on spur gears. However, helical gears are generally used in industry, and their contact behavior deserves more attention to establish a realistic base for detailed friction, wear and life studies. This study focuses on the modeling of helical gear contact with tooth deflection. A calculation model for helical gear contact analysis is introduced. Helical gear surface profiles are constructed from gear tool geometry by simulating the hobbing process. The model uses three-dimensional finite elements for the calculation of tooth deflection including tooth bending, shearing and tooth foundation flexibility. The model combines contact analysis with structural analysis to avoid large meshes. Tooth foundation flexibility was found to have an essential role in contact load sharing between the meshing teeth, whereas contact flexibility plays only a minor role. The capability of different local contact calculation methods was also studied.     

Experimental simulation of gear contact along the line of action

In highly loaded gears, lubricated rolling/sliding contact conditions change greatly along the line of action. This leads to variation in gear frictional properties and to failures such as pitting and scuffing that take place in different positions along the tooth flank. Information on instant contact behavior is therefore very useful, but this kind of measurement in real gears is extremely complicated. Single spur gear geometry has been simulated at 38 steady-state measuring points along the line of action using a twin-disc test device focusing on the friction coefficient and on temperature and lubrication conditions. Twin-disc simulations were adjusted to match real gear experiments by using similar maximum Hertzian pressure and surface velocities. The results show that the curve shapes for the mean friction coefficient as a function of pitch line velocity are similar to the corresponding experimental results with real gears. Further, the calculated thermal Λ-values of real gears and the measured mean contact resistance correspond well. This approach shows potential for simulating gear friction and failure mechanisms along the line of action.     

小模数齿轮单面啮合测量机的研制

小模数齿轮因几何与机械性能的限制,传统的单向驱动式单面啮合测量技术一直未能在其测量中得到应用.针对此问题,提出了"双向驱动"式单面啮合测量新原理,基于该原理研制了小模数齿轮单面啮合测量机.重点介绍齿轮单面啮合测量新原理、测量机的组成及关键技术.在结构设计方面,采用两轴系平行但不在同一端的结构布局,利用两伺服电机同步驱动实现两轴系的主动回转,通过微角度测量装置获取测量齿轮相对其轴系的微转角差,开发无线传输技术进行信号采集.在软件设计方面,基于Microsoft Visual C++6.0开发了小模数齿轮单面啮合测控软件.实际测试表明,该测量机能实现小模数齿轮的快速测量.     

Reverse engineering of machine-tool settings with modified roll for spiral bevel pinions

Although a great deal of research has been dedicated to the synthesis of spiral bevel gears, little related to reverse engineering can be found. An approach is proposed to reverse the machine-tool settings of the pinion of a spiral bevel gear drive on the basis of the blank and tooth surface data obtained by a coordinate measuring machine(CMM). Real tooth contact analysis(RTCA) is performed to preliminary ascertain the contact pattern, the motion curve, as well as the position of the mean contact point. And then the tangent to the contact path and the motion curve are interpolated in the sense of the least square method to extract the initial values of the bias angle and the higher order coefficients(HOC) in modified roll motion. A trial tooth surface is generated by machine-tool settings derived from the local synthesis relating to the initial meshing performances and modified roll motion. An optimization objective is formed which equals the tooth surface deviation between the real tooth surface and the trial tooth surface. The design variables are the parameters describing the meshing performances at the mean contact point in addition to the HOC. When the objective is optimized within an arbitrarily given convergence tolerance, the machine-tool settings together with the HOC are obtained. The proposed approach is verified by a spiral bevel pinion used in the accessory gear box of an aviation engine. The trial tooth surfaces approach to the real tooth surface on the whole in the example. The results show that the convergent tooth surface deviation for the concave side on the average is less than 0.5 μm, and is less than 1.3 μm for the convex side. The biggest tooth surface deviation is 6.7 μm which is located at the corner of the grid on the convex side. Those nodes with relative bigger tooth surface deviations are all located at the boundary of the grid. An approach is proposed to figure out the machine-tool settings of a spiral bevel pinion by way of reverse engineering without having known the theoretical