基于ANSYS的柔轮应力与应变的有限元分析

通过Pro/E建立了8组不同厚径比的柔轮和波发生器的三维实体模型,并导入到ANSYS中建立有限元模型.在波发生器外圈与柔轮内圈问建立面-面接触对,模拟波发生器与柔轮接触的边界条件.在柔轮装入波发生器的条件下,进行了8组不同厚径比柔轮的应力和应变分析,得出了柔轮的厚径比β=0.008～0.020时柔轮受到的应力值最小,同时还分析验证了柔轮的应力和应变在轴向和周向的分布规律.     

基于ANSYS的谐波减速器柔轮受力分析

通过UGNX4．0建立柔轮和波发生器的三维实体模型,并用parasolid格式导入ANSYS。采用SOL—ID185六面体单元用sweep方式对柔轮进行网格化,而波发生器无需网格化,建立有限元模型。在波发生器外柱面与柔轮内柱面之间建立两对面-面接触,更真实地模拟出柔轮的边界条件,然后在波发生器长轴方向对称位置的两个轮齿的节点上施加等效于扭矩的切向力,从而研究出柔轮的应力分布和变形与载荷的关系。     

谐波齿轮传动机构不同参数柔轮的装配应力分析

针对谐波齿轮传动机构在传动过程中,柔轮承受交替载荷和周期变形的问题,分析了柔轮装配下应力的分布情况。基于ANSYS有限元软件,在凸轮式波发生器装配作用下,定义了波发生器与柔轮"刚—柔"面面接触;采用控制变量法改变了柔轮结构参数,探究了空载下柔轮变形及应力分布规律,以及不同几何结构参数对柔轮内部各部分应力变化的影响;分析了在结构参数不变的情况下,空载与负载下的柔轮应力变化情况。研究结果表明:柔轮装配波发生器后,筒体受到的变形主要在波发生器长轴处;柔轮空载时,应力的分布及大小主要和波发生器有关,同时应力大小也会受到长径比、齿宽及筒体厚度影响;柔轮应力随着负载的增大而逐渐增大。     

谐波传动中杯形柔轮的应力分析

本文采用有限元混合法较全面地计算和分析了二点式波发生器作用下杯柔轮中的应力分布规律,得出了杯形柔轮的破坏位置以及其最大应力与长径比、直径比、底杯尺寸等的关系曲线,分析了变截面底板结构的优点及凸缘在柔轮结构中所起的作用,对杯形柔轮各结构参数给出了推荐使用值。     

ANSYS平台上的双圆弧齿廓谐波传动柔轮有限元分析

应用有限元法对杯形柔轮的应力进行分析,根据柔轮的工作状况,柔轮的有限元研究属薄壳几何非线性问题.运用有限元分析软件ANSYS,建立柔轮啮合的仿真实体模型,在啮合齿对接触边界的节点之间建立面-面的接触单元,对柔轮和波发生器工作时的柔性变形进行有限元分析,得到柔轮应力分布规律和位移场.     

Y56低速电机两种谐波发生器对柔轮的作用比较

由于波发生器的结构对柔轮的受载状态有很大的影响,针对谐波齿轮传动中柔轮的主要破坏疲劳破坏,就Y56型低速电机提出了从波发生器的结构入手,分析柔轮的疲劳破坏的方法.并对谐波齿轮传动中的圆盘式波发生器和凸轮波发生器分别作用在柔轮时,对柔轮作有限元接触分析,找出了两种波发生器作用下谐波齿轮传动所适用的范围:凸轮波发生器作用下...     

谐波减速器组合曲线凸轮波发生器的设计与分析

波发生器的形状直接影响柔轮的受力特性。柔轮是谐波减速器中最薄弱的部分,为提高其寿命,介绍了一种基于圆锥曲线组合的凸轮波发生器的设计。组合曲线凸轮波发生器轮廓由抛物线、连接圆弧和偏心圆弧组合而成;将抛物线与连接圆弧、连接圆弧与偏心圆弧平滑过渡作为约束条件,通过正交实验确定组合曲线凸轮波发生器各段曲线参数,分析了各参数对柔轮最大等效应力的影响程度;利用有限元软件,分别对标准椭圆凸轮和组合曲线式凸轮作用下的柔轮进行了瞬态动力学分析,并基于分析结果,利用nCode-Designlife软件,对柔轮的疲劳寿命进行了研究。结果表明,组合曲线凸轮波发生器作用下的柔轮最大等效应力比标准椭圆凸轮波发生器作用下的低;组合曲线凸轮波发生器作用下的柔轮啮合区的齿圈前后端应力明显降低,应力分布更加均匀,疲劳寿命也有所提高。     

谐波齿轮减速器

谐波齿轮减速器主要由刚轮、柔轮和波发生器三部分组成。柔轮是一个具有外齿的弹性薄壁零件,刚轮是一个刚性内齿圈,而波发生器是由一个椭圆凸轮及压配在凸轮上的薄壁轴承组成(如图所示)。波发生器压入柔轮内,柔轮在波发生器径向力作用下产生变形。在椭圆凸轮长轴方向,刚轮(设固定件)和柔轮的轮齿完全啮合。而短轴方向,刚轮和柔轮的轮齿完全脱开。由于刚轮齿数比柔轮齿数多2个,在输入扭矩作用下凸轮顺时针方向旋转时,椭圆长轴也随发     

谐波齿轮传动中柔轮应力的有限元分析

建立了谐波齿轮传动中杯形柔轮与波发生器接触分析的有限元模型,对常用的滚轮、凸轮及圆盘式波发生器作用下柔轮空载时的应力进行了计算分析,得到了柔轮壳体的应力分布状况。研究表明:柔轮壳体上的最大应力出现在齿圈与波发生器的接触部位,齿圈上沿圆周方向的应力呈对称分布,在长轴和短轴处较大,在两者中部较小;沿齿圈宽度上柔轮的应力分布状况在双滚轮和四滚轮下相近,最大应力位于齿圈后端;双圆盘和凸轮下应力分布相近,最大值位于齿圈前端;在同样大的变形下,采用圆盘波发生器时柔轮上具有较小的应力。     

考虑谐波齿轮传动间隙的柔轮变形状态

本文通过对谐波齿轮传动凸轮式波发生器机构的间隙进行分析计算,在合理假设柔轮—波发生器之间的载荷分布模型基础上,建立了合理的柔轮壳体变形数学模型。运用壳体理论、优化理论,推导了在波发生器—柔轮系统具有间隙条件下的柔轮实际原始曲线数学方程从而为进一步研究真实状态下谐波齿轮传动的啮合几何问题与结构强度问题奠定了基础。     

Effect of surface texturing on the elastohydrodynamic lubrication analysis of metal-on-metal hip implants

With the development of surface processing techniques, applications of bearing components have been introduced with specific surface textures to take advantage of lubrication.An advanced numerical model was established to simulate the mixed EHL problem of a metal-on-metal hip prosthesis with dimpled surface texturing. The surface texture with simple cylindrical dimples was numerically simulated, under both steady state and walking conditions.The present results showed that surface texturing may have a potentially beneficial effect on the reduction of asperity contact ratio and the improvement of lubrication performance of metal-on-metal hip replacements, particularly under predominant boundary lubrication conditions.     

Determination of the grinding wheel profile and its setup for use in finishing cylindrical gears with an evolvent profile

The present work is a continuation of the first part of the article and is devoted to the geometric calculation of shape parameters of the working surfaces of disk-shaver teeth for use in finishing cylindrical gears with an evolvent profile. A method has been proposed for determining the shape of the working surfaces in disk-shaver teeth during the recessed shaving of cylindrical gears with technologically modified teeth. In this case, the machined gear tooth surfaces are discretely specified, and consequently familiar analytical methods of tool profiling are unacceptable.     

曝气机用圆锥-圆柱齿轮减速器设计改进

对横轴式转刷型表面曝气机用三级圆锥-圆柱齿轮减速器低速级圆柱齿轮副出现因点蚀、剥落特别是断齿而失效的现象进行了分析,从速比分配、材质选用等方面进行了设计改进。     

3D graphical method for profiling gear hob tools

This paper approaches the issue of profiling gear hob bounded by a cylindrical helical surface with constant pitch, reciprocally enveloping with an ordered surfaces curl. The process kinematics of generation reproduces the 3D gear between the worm and the wheel. This gear has crossing axes and it is used for the profiling of the primary peripheral surface of the gear hub in the intermediary surface method (the common rack-gear of the surfaces curl to be generated and the primary peripheral surface of the gear hob). An algorithm in the CATIA design environment is presented, based onto an original method for the determination of the reference rack-gear form—the rack-gear reciprocally enveloping with the surfaces curl, using the principle of the cylindrical helical motion decomposition in translation and rotation motions. Graphical and analytical profiling examples are presented for the gear hob for generation of a parallel spline shaft and for the generation of a toothed wheel with involute teeth. Solutions for the interference problems, problems due to the singular points onto the profiles, are presented.     

Calculation of the bending stresses of involute teeth with longitudinal surface modification

The results of the simulation of the deformation mode in the root of the teeth of cylindrical involute gears under the action of a concentrated force are given. It is the first step in determining the bending strength of involute teeth in the case that at least some of them (those in a pinion or in a gear) have a longitudinal surface modification providing for a contact that is a point one from the theoretical point of view and local from the practical point of view. The investigations have been performed using the finite-element model developed in an ANSYS environment. Taking into account the effective (equivalent) stresses responsible for damaging the material of the teeth, the volume factor of the shape of the tooth has been reduced to a form that makes it possible to use the bending durability limits specified for ordinary (unmodified) teeth of involute gears with a theoretically linear contact, which enter the working stresses for estimating the bending resistance.     

Prediction of microgeometrical influences on micropitting fatigue damage on 32CrMoV13 steel

Micropitting is a form of surface fatigue damage that occurs in the gear teeth. It is due to the effect of variation in the mechanical loading in the contact zone between the two teeth, induced especially by flank roughness. In this study, generic roughness profiles were built with geometrical parameters to simulate the contact between two rough surfaces. Using elastohydrodynamic lubrication code and Crossland's fatigue criteria, the influence on fatigue lifetime was analysed for changes in each parameter. The relevant parameters were determined that influence (i) the conventional pitting, (ii) the extent to which the von Mises equivalent stress exceeds the material yield stress in the zone where micropitting occurs, and (iii) the fatigue lifetime for steel teeth. With nitriding benefits, the same trends were shown with weaker effects.     

基于Pro/E渐开线圆柱齿轮参数化设计及模态分析

根据渐开线圆柱齿轮生成原理,在Pro/E中建立了渐开线圆柱齿轮的参数化模型,该模型不仅可以自动精确生成直齿、斜齿及其变位齿轮,而且通过条件控制语句,实现了任意齿数的齿轮设计.根据模态分析理论,利用Pro/MECHANICA对斜齿轮的模态进行了分析计算,总结了在定分度圆下不同齿数模数组合及轴孔直径对齿轮固有频率的影响,为渐开线圆柱齿轮传动的合理、高效设计和动态响应分析提供了理论依据.     

A finite element simulation of the two-dimensional head/tape interface for head contours with longitudinal bleed slots

The two-dimensional (2D) steady-state linear head/tape interface with surface asperity contacts and tape shear deformations is analyzed using the finite-element method. A non-uniform mesh is utilized to improve the computational efficiency and to simulate cylindrical heads with longitudinal slots. Numerical results for the head/tape spacing and contact pressure are obtained for 2D head/tape interfaces using cylindrical heads with longitudinal slots. In addition, numerical examples are presented for the head/tape spacing and the pressure distribution using heads consisting of triple arc elements with and without longitudinal slots.     

航空航天薄壁框体零件的高效加工工艺分析

分析航空航天薄壁框体零件的高效加工工艺。针对目前所出现的薄壁零件加工问题,分析其变形原因和有效控制措施,以此得到航空航天薄壁框体零件的高效加工工艺。采用数控高速加工工艺,粗加工一时效处理一半精加工一精加工的工艺原则,“小切深,快刀走”的走刀方式,合理计算精加工余量,能有效提高加工效率,实现薄壁框体零件的高效加工。数控高速加工工艺不但可以提高航天航空薄壁框体零件的加工效率,还可对零件加工变形问题进行有效控制,实现其零件的高效加工,可推广使用。