人字齿轮直线型对角修形设计及成形磨原理

为了降低承载传动误差波动产生的振动激励，提出了成形磨人字齿轮直线型对角修形优化设计。根据ISO对角修形定义，计算齿顶、齿根修形起始线在旋转投影面上的螺旋角，将修形曲线设计为直线型，给定最大修形量，确定对角修形的齿面方程。利用齿面接触分析和轮齿承载接触分析，以工作载荷下人字齿轮承载传动误差波动量最小为优化目标，采用遗传算法优化对角修形参数。确定以目标修形齿面法向偏差的平方和最小的目标函数，以螺旋角、模数、压力角为设计变量，采用遗传算法分别对齿顶和齿根修形区域进行逼近，从而实现对角修形的成形磨加工。结果表明，人字齿轮直线型对角修形可以将承载传动误差波动量降低到36.65%；采用三截面砂轮成形磨的理论误差控制在1μm以内，获得较高的齿面精度；试验人字齿小轮齿的检测结果控制在4级精度以内，并进行了齿轮副的滚检试验，从而验证该方法的有效性。     

Effects of flank deviation on load distributions for helical gear

Flank deviation is one of the important factors that greatly affect helical gear strength. A qualitative analysis is performed using finite element method (FEM) for the effects of flank deviation on load distributions for helical gear based on ANSI/AGMA ISO 1328-1 (standard for cylindrical gears — ISO System of Accuracy — Part 1: Definitions and Allowable Values of Deviations Relevant to Corresponding Flanks of Gear Teeth). To analyze the effects of flank deviation, tooth contact analysis (TCA) is developed and load distributions of helical gears with flank deviation are presented. Load distributions in contact lines are derived and compared to each other under grade 5 and 7 after taking five types of flank deviation, including single pitch deviation, profile form deviation, profile slope deviation and helix form deviation as well as helix slope deviation, into account. It is found that the effects of individual flank deviation on load distribution have the superposition property. Flank crowning and tip relief corrections must be carefully regarded in the design process because of the effects of flank deviation on load distributions.     

内啮合斜齿轮高精度三维有限元自动建模方法

为提高内啮合斜齿轮有限元接触分析的建模速度和模型精度,提出了一种齿轮高精度三维有限元模型的自动建模方法。基于齿轮插刀齿廓方程,利用齿廓法线法,得到包括齿根过渡曲线的内、外斜齿轮端面齿廓,建立了内、外齿轮参数化粗网格有限元模型。开发了表层六面体网格剖分方法,自动识别齿面接触带单元,进行分级剖分细化,保证了有限元模型的建模精度和网格密度。进行了齿面接触分析,得到了内啮合斜齿轮的弯曲应力、接触应力、接触印痕、传动误差、时变啮合刚度和载荷分配率。粗细网格有限元模型计算结果对比分析表明,该方法提高了内啮合斜齿轮有限元建模效率和计算精度,缩短了计算时间,为快速准确的齿轮接触分析奠定了基础。     

内,外啮合斜齿轮三维接触应力有限元分析

本文针对建立斜齿轮接触应力有限元模型所涉及的若干问题进行了分析,在此基础上编制了包含内、外啮合并计及轮体结构的斜齿轮接触应力分析有限元建模程序;针对７个考题的有限元结果与ＩＳＯ、ＡＧＭＡ４１１．０２、ＡＧＭＡ２００１齿轮标准的计算结果进行了对比验证分析。     

粉末冶金斜齿轮系统振动频率响应分析

利用有限元法建立包含齿轮副、传动轴、轴承和箱体的齿轮系统完整的动力学模型。使用有限元分析软件 MSC.Nastran计算了在齿轮动态激励下粉末冶金斜齿轮系统的振动响应,并与38CrMoAl刚性齿轮系统进行比较。     

Static/dynamic contact FEA and experimental study for tooth profile modification of helical gears

With the development of high-performance computers, the contact finite element analysis (FEA) method has become more and more popular for studying both the static and dynamic behaviors of gear drives. In this paper, a precise tooth profile modification (TPM) approach of the helical gear pairs is presented first. The type and amount of the TPM are accurately determined by the static contact FEA results. Then dynamic contact simulations for the helical gear pairs with and without TPM are, respectively, carried out to evaluate the effect of the presented TPM approach on vibration reduction. No additional assumptions and simplifications are required for the static and dynamic contact analysis models. Vibration comparison experiments are also carried out on an open power flow test rig. Both the simulated and experimental results show that the presented precise TPM of helical gears is effective on vibration reduction around the working load, and the dynamic contact simulation is effective in estimating the effect of the TPM on vibration reduction in the designing stage.     

精确载荷分布下斜齿轮三维建模及弯曲应力分析

从范成法加工齿轮的原理出发,利用三维建模软件建立了渐开线斜齿圆柱齿轮的精确模型。根据齿轮啮合变形协调方程,利用线性规划法求解了齿轮副在各啮合节点的载荷分布情况,并计算了轮齿间的载荷分配率。利用有限元软件ANSYS计算了完整齿轮模型在啮合过程中的最大齿根弯曲应力,为齿轮弯曲强度校核提供了依据。研究结果发现,斜齿轮的最大弯曲应力有可能出现在多齿啮合的区域,这种现象与直齿轮有所不同。     

基于MATLAB与SolidWorks联合建模的渐开线圆柱直齿轮接触特性仿真分析

通过渐开线直齿轮齿廓方程在MATLAB中构建出渐开线直齿轮的点云模型生成精确地齿廓,将点云数据导入到SolidWorks中构建出齿廓精确的渐开线直齿轮副的三维模型;然后对渐开线直齿轮副进行理论接触应力计算,并对联合建模的齿轮副与参数化建模的齿轮副进行接触应力的有限元仿真分析和动力学仿真分析结果进行对比.结果表明:联合建...     

齿轮修形参数对变速箱传动特性影响的研究

针对齿轮传动中的振动和噪声问题,以Masta为仿真分析平台,通过对某变速箱主减速齿轮修形的仿真计算,得到了齿顶修缘量、齿形和齿向鼓形量等修形参数的变化对齿轮传动特性的影响规律。在对齿轮传动误差和齿面最大接触应力变化规律研究的基础上,选取了目标机型主减速齿轮的最佳修形参数。噪声试验结果表明,变速箱主减速齿轮修形后,齿轮啸叫得到了明显改善。     

旋转齿轮瞬时接触应力和温度的分析模拟

建立了高速齿轮传动轮齿瞬时接触温度的分析方法和模型;采用赫兹接触理论和有限元接触分析方法分析了标准渐开线齿廓和齿顶修形齿廓的齿面接触压力;研究了啮合过程中轮齿的相对滑动速度和齿面摩擦因数以及摩擦热流密度的计算方法;建立了轮齿本体温度的有限元温度分析模型;计算了轮齿接触面的瞬时温升;分析了标准和齿顶修形渐开线齿轮的轮齿本体温度和瞬时接触温度及相关因素对它们的影响。     

斜齿轮振动噪声分析方法

齿轮啮合传动的不平稳是产生振动噪声的主要原因,需要对齿轮啮合传递的动态过程及其规律进行研究。首先,以自动变速器中一对常啮合斜齿轮为研究对象,分别采用有限元法和切片理论计算斜齿轮的传递误差,用以衡量斜齿轮啮合传动的平稳性。然后,根据齿轮修形的经验公式,确定斜齿轮修形参数的范围。基于切片理论,采用列举法,以降低传递误差波动、改善齿面载荷分布为优化目标,确定最优修形方案。最后,通过分析自动变速器的振动噪声台架实验测试结果,有效地验证了笔者采用的方法及模型的可行性。     

三维螺旋齿廓曲面接触强度计算模型

从三维螺旋齿廓曲面的形成得到接触强度计算模型。介绍改进的有限元齿廓曲面接触强度计算法,包括改进的计算方法、确定产生最大接触应力时啮合位置的方法等。提出计入齿面接触载荷非线性及啮合齿对数发生变化时的斜齿轮三维强度有限元建模方法及程序,给出应用实例。该方法使齿面接触强度计算更接近工况。此方法还可应用于圆柱螺旋齿轮、锥齿轮、蜗轮蜗杆等传动接触强度的计算。     

基于MW级风力机齿轮啮合的有限元分析

随着风力机制造量级越来越大,传动扭矩增大,齿轮的设计越来越重要,否则齿轮很快出现疲劳点蚀导致损坏。运用有限元方法对MW级风力机齿轮进行参数化APDL精确建模,建立一对啮合齿轮模型,然后进行网格划分,生成有限元模型,计算齿轮啮合时的接触应力和弯曲应力。并和GB/T3480-1997接触应力理论公式比较,验证了有限元方法的正确性,同时得出齿轮接触应力分布和最大应力产生的部位及弯曲应力比接触应力小的多。从而为风力机齿轮的设计提供不同材质、不同型线的快速研究提供可能,同时为齿轮的设计提供依据。     

基于Pro/E和ABAQUS的直齿轮强度分析

选取一对外啮合渐开线直齿圆柱齿轮,用 AGMA 标准对齿轮的接触强度及弯曲强度进行计算;在 Pro/ E 软件中精确建立该啮合齿轮的三维模型,将模型文件导入 Abaqus 软件,对齿轮啮合进行有限元强度分析,最后将两者的分析结果进行对比。结果表明,利用有限元方法分析齿轮的强度是可行的。     

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。     

基于APDL的斜齿轮造型技术

在斜齿轮的CAE分析中,需要对它进行参数化造型,为实现这一目的,利用了ANSYS的APDL.首先在ANSYS中形成端面齿廓,再沿螺旋线拖拉,直接生成了一对斜齿轮的参数化模型,便于进一步分析齿轮的齿面接触应力和齿根应力,以及斜齿轮的啮合过程,在实际中应用获得了良好的效果.     

An investigation on the influence of modification parameters on transmission characteristics of planetary gear system

A new gear tooth modification model of planetary gear system was established by considering the characteristics of tooth longitudinal crowning modification and tooth profile modification. Using this model, the influences of modification parameters on the time-varying mesh stiffness, transmission error, contact spots and dynamic response of the planetary gear system were analyzed through numerical analysis. The results show that tooth profile modification can effectively restrain the mesh stiffness sudden variation in the single and double tooth alternation of both the internal and external mesh pairs, and significantly decrease the transmission error fluctuation. However, longitudinal crowning modification has no marked influence on mesh stiffness sudden variation or transmission error fluctuation. The tooth profile modification can significantly reduce the sudden variation of tooth surface load during gear mesh course. Longitudinal crowning modification can make the tooth surface load evenly distributed in tooth width direction. When the external meshing pairs are modified at the tooth profile individually, the magnitude values of main response resonance peaks of internal meshing pairs have a great reduction, but those values of external meshing pairs change slightly. In the case of tooth profile modification of the internal meshing pairs, the phenomenon is reversed. By contrast with tooth profile modification, longitudinal crowning modification has little influence on the resonance peaks of internal and external meshing pairs.

     

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.     

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.     

矿用减速器斜齿轮副动态啮合仿真分析

利用大型有限元分析软件ANSYS建立了某矿用减速器变位斜齿轮副多齿对啮合的有限元非缌性接触分析模型.基于该模型,对齿轮副进行了在一定工况下的动态啮合仿真分析,得出瞬态啮合时轮齿的接触状态、接触应力、齿根弯曲应力以及主从动齿轮的转矩、转速随啮合位置变化的规律符合实际啮合规律,同时得到最恶接触位置,并在此位置进行了静态接触强度分析.分析结果表明,动态啮合仿真能够真实反映轮齿的接触状态、接触应力以及齿根弯曲应力的动态变化,静态接触分析进一步验证动态啮合分析的可靠性,也为疲劳寿命分析提供了依据.