三环减速器多齿啮合效应的有限元分析

通过有限单元法,并借助ANSYS有限元分析软件对三环减速器的多齿啮合效应进行了分析,得到了三环减速器传动时的实际接触齿数、啮合齿载荷分配以及von Mises应力变化规律.     

螺旋锥齿轮拟合齿面啮合特性分析方法

已知齿面测量的采样点，利用微分几何及Ferguson参数样条曲面原理，建立了螺旋锥齿轮齿面拟合的数学模型。根据优化求极值复合形方法和共轭理论，通过变定义域，快速求解齿轮副拟合齿面接触点，并运用V—H接触区调整方法，研究了拟合齿面接触迹、接触区和运动误差曲线的求解算法，绘制出相关图形并给出了实例。     

平面多齿啮合弹性共轭曲面求解

运用多齿啮合弹性共轭曲面理论 ,探讨在弹性条件下 ,给定载荷分配的平面啮合的齿廓求解方法。通过实例计算 ,给出本方法的求解过程     

任意齿差纯滚动活齿传动齿形设计方法及啮合特性研究

由于高次多项式类曲线具有无刚、柔性冲击的特点,为实现任意齿差纯滚动活齿传动,提出基于五次多项式类曲线的新齿形设计方法。基于转速变换和包络原理,推导出中心轮齿廓方程,制定中心轮避免齿形干涉的设计条件,分析中心轮齿形曲率半径变化规律,阐释活齿轴半径对中心轮齿形的影响;根据活齿传动啮合原理,以压力角表达式表征啮合特性,并对影响最小压力角及传力齿廓区间大小的表征参数进行分析,为任意齿差纯滚动活齿传动结构几何参数的选择提供了设计依据。给出设计实例,验证理论分析结果的有效性,仿真结果表明,高次多项式类任意齿差纯滚动活齿传动受力效果好,传动平稳,设计方法简单,易于形成模块化与系列化设计,具有广阔的应用前景。     

基于热弹变形的圆柱齿轮理想修形曲线

提出一种求解圆柱齿轮理想修形曲线的方法，应用耦合热弹接触有限元技术，分析轮齿在齿间载荷分配、齿面压力分布、轮齿弹性变形、齿面摩擦、轮齿温度场、轮齿制造误差因素作用下齿轮传动的啮合刚度，尽可能真实地模拟运转过程中啮合轮齿的形态，确定轮齿的刚度变化规律，通过数值拟合寻求最佳修形参数，在此基础上，得到圆柱齿轮理想修形曲线。     

Nonlinear dynamic characteristics of geared rotor bearing systems with dynamic backlash and friction

Effects of the friction and dynamic backlash on the multi-degree of freedom nonlinear dynamic gear transmission system, which incorporate time varying stiffness, are investigated. Firstly, the relationship between gear central distance error and backlash is deduced and the dynamic backlash is defined, subsequently a multi-degree of freedom nonlinear dynamic gear transmission system is developed with dynamic backlash, friction and time varying stiffness. The nonlinear dynamic system is solved by the Runge-Kutta method. The results show that the friction force may enlarge the displacement magnitude and affect the high frequency parts significantly in frequency domain at low speed. But the RMS of the steady response is reduced on the effect of friction. The difference between the constant backlash and the dynamic backlash models is also discussed. The system may enter into previous chaotic motion due to the effect of dynamic backlash. Finally, no impact motion, single-side impact motion and double-side impact motion are also predicted in the new dynamic backlash model.     

The Research on Toroidal Drive

0INTRODUCTIONToroidaldrivewasinventedbyU.S.scholarM.R.Kuhenlein1966[l].Itconsistsof(l)centralinputworm,(2)wormWheelplanet,(3)statorwithtoroidalshapetooth,(4)centraloutputrotor,and(5)meshingrollers(Fig.I).Whileworking,tLhewormisadrivingelement,andthewormwheelplanetisadrivenelement.Themeshingoftheplanettothewonnandtheplanettothestatoriscompletedbytherollerswhicharedistributedunifolmlyarotindthecircleoftheplanet.Toroidaldrivehasthepropel-tiesofcompactnessandhigherefficiency,andhas,theref…     

单齿转子式压缩机的转子设计与性能分析

基于单齿转子的设计方法与曲线的啮合理论,提出一种新型单齿转子,完善常见型线的啮合模型,构建该新型转子的型线参数方程,分析转子几何参数的关系,利用ANSYS分析新型单齿转子的力学性能。结果表明,所提出的新型单齿转子具有设计合理、设计方法简单、力学性能好的优点。     

A new method for coarsening tetrahedral meshes

To coarsen a mesh, we usually remove a set of selected nodes one by one. Currently, the basic operation used to remove a node is edge collapsing, which does not perform well when applied to handling narrow regions in a tetrahedron mesh and could produce low‐quality elements or even fail to give valid results. To overcome the drawbacks of edge collapsing, we present a new node‐removal operator created by revising a topological transformation called small polyhedron reconnection. This new operator can guarantee success if the cavity that forms after a node is removed is meshable, and it produces higher‐quality results and keeps the nodes unmoved, which is preferred for applications such as multigrid hierarchies. In addition, 2 other aspects of mesh coarsening that determine whether a node should be removed and the sequence in which to remove the selected nodes are also studied. Our strategy consists of constructing a coarse node set using the sphere‐packing method and removing the nodes in a reversed kd‐tree sequence. The excellent performance of the new method is demonstrated by applying it to examples of adaptive meshing and multigrid hierarchy creation and comparing the results with those of the edge collapsing method.     

考虑齿距累积误差的人字齿轮系统动态特性分析

基于Timoshenko梁理论和有限单元法,引入时变啮合刚度和综合啮合误差,建立了人字齿轮系统动力学模型,研究了齿距累积误差对人字齿轮系统动态特性的影响。研究表明:齿距累积误差使动态传递误差出现显著的轴频成分和调制边频带。当负载扭矩较小时,边频成分大于啮合频率及其倍频成分,随着负载扭矩的增加,啮合频率及其倍频成分逐渐增强。当齿距累积误差相位不同时,人字齿轮系统将出现明显的轴向窜动现象。同时,齿距累积误差相位差对系统振动影响显著,通过调整相位差可以显著降低系统振动。研究结果可为人字齿轮系统低噪声设计加工与装配提供理论依据。