Some studies on hypoid face gears

Some of the geometric characteristics of a hypoid face gear in mesh with an involute spur pinion are analysed. These geometric characteristics include (a) the maximum diameter of the hypoid gear to avoid pointing of the teeth, (b) the minimum diameter for avoiding undercutting, (c) the contact ratio, (d) the field of contact and (e) the variation of the pressure angle along the face of the pinion. The variations of the above quantities with different parameters such as number of teeth of the pinion, transmission ratio, amount of offset and the pressure angle of the cutter are given.     

准双曲面齿轮刮削的计算

分析由于采用硬质合金刮削刀具 ,使准双曲面齿轮切齿原理产生的变化 ,讨论准双曲面齿轮刮削加工计算中 ,刮削刀具参数的计算。所得结果可用于准双曲面齿轮刮削切齿的精确计算     

The influence of misalignments on mesh performances of hypoid gears

A new method for tooth contact analysis in mismatched hypoid gears is applied for the investigation of the influence of misalignments of the mating members on mesh performances. By using the corresponding computer program, the influence of running offset error, pinion’s axial adjustment error, and angular position errors of the pinion axis on the shape and position of path of contact and of potential contact lines under load, on separations along these contact lines, on angular displacements of the gear member, and on the variation of the angular velocity ratio through a mesh cycle, have been determined. The results obtained have shown that the position errors of the mating members cause edge contact on the tip of the pinion or gear tooth, worsen the conjugation of the contacting tooth surfaces, and considerably increase the angular displacements of the gear member and the angular velocity ratio variation through the whole mesh cycle, that considerably worsens the mesh performances.     

准双曲面齿轮准静态接触分析和试验研究

建立了精确的准双曲面齿轮的轮齿面和过渡曲面数学模型;选择用平均接触椭圆长半轴、接触线方向角和传动误差曲线交点来评价齿面接触斑点和传动误差;以一个准双曲面齿轮副为计算实例,建立了适合准静态齿面接触分析的准双曲面齿轮传动系统有限元分析模型;通过准静态加载齿面接触特性分析,得到齿根弯曲应力、接触应力和传动误差的变化规律,分析载荷的影响情况,并比较了有限元结果与经验公式计算结果。开发了准双曲面齿轮试验台,进行齿面接触斑点和齿根弯曲应力检测,试验结果与仿真结果的一致性较好。     

摆线齿准双曲面齿轮模拟加工系统建模

简单介绍摆线齿准双曲面齿轮模拟加工系统,以左旋小齿轮模块为例,利用AutoCAD 2006的二次开发工具VBA对摆线齿准双曲面齿轮模拟加工系统三维建模过程进行详细阐述,主要包括齿轮坯实体的构建和铣齿刀盘实体建模.采用摆线齿准双曲面齿轮模拟加工系统中的AKM-852铣齿机加工出10齿左旋小齿轮实体,为摆线齿准双曲面齿轮的优化设计和加工奠定理论基础.     

准双曲面齿轮CAD系统的设计与实现

运用VC+ + 与AutoCAD二次开发工具ObjectARX2 0 0 0开发一种准双曲面齿轮CAD系统 ,介绍该系统的体系结构和主要内容 ,简述开发过程和实现方法。该系统能方便完成图表数据检索、齿坯设计、强度校核、绘图、调整卡计算输出。     

数控磨齿机加工准双曲面齿轮

分析现阶段我国准双曲面齿轮的磨齿工艺存在的问题,提出在PHOENIX系列数控磨齿机上对准双曲面齿轮进行磨齿的工艺参数计算方法.加工试验表明,采用该种方法计算的参数,适合我国汽车驱动桥准双曲面齿轮的磨齿加工,并能保证高质量、大批量的生产要求.     

准双曲面齿轮研磨运动模型研究

分析准双曲面齿轮研磨原理,建立V/H与齿面啮合关系的数学模型。通过对齿面的接触印痕仿真与滚检试验。证明,所建之模型能对齿面研磨中研磨点的位置、移动方向、齿侧间隙进行准确的控制,为螺旋锥齿轮的研磨提供了理论指导。     

螺旋锥齿轮数控加工3维仿真研究

在分析了螺旋锥齿轮数控加工原理后，采用面向对象技术和计算机辅助设计系统中的3维建模功能，提出了CNC铣齿机床、齿轮毛坯和盘铣刀3维几何模型的具体构建方法；利用简化的齿轮毛坯实体模型和盘铣刀实体模型做布尔减运算，来实现模拟工件材料的去除过程；最终给出的加工仿真实例和实际加工结果，验证了加工仿真方法的正确性。所获得的仿真结果可为齿面接触分析、有限元应力分析和齿轮的数控加工等提供了精确的3维实体模型。     

螺旋锥齿轮螺旋变性半展成法数控加工研究

螺旋锥齿轮齿面接触区的形状、大小和位置,对齿轮的平稳运转、使用寿命和噪声具有直接影响。针对齿轮副接触情况,利用数控铣齿机调整的灵活性,将螺旋运动应用于螺旋锥齿轮的小轮加工过程,在啮合原理和产形轮原理的基础上,提出了螺旋变性半展成法,研究了螺旋变性半展成法的加工原理和切齿方法,建立了螺旋锥齿轮副的切齿模型和数字化加工模型,给出了机床调整关系式。齿面接触分析(TCA)结果表明:使用螺旋变性半展成法加工螺旋锥齿轮副可以从本质上避免接触区呈对角接触的现象,降低了调整修正过程的复杂程度。     

准双曲面齿轮接触斑点的新型分析系统

由准双曲面齿轮的分度锥和装配尺寸关系确定机床设置.利用坐标系转换建立齿面的三维形状.在此基础上建立接触斑点分析系统.这种新的分析系统所开发的高扭矩的齿轮可用于汽车的新型传动系统,其接触斑点在提高疲劳强度和降低噪音方面都可以达到优化.     

Cutting-head optimization to improve the reliability of conical and hypoid gears

The use of one- and two-sided cutting heads to ensure that the longitudinal tooth curvature resembles logarithmic and Archimedes spirals is considered. The influence of such shaping on the operational reliability of conical and hypoid gears with round teeth is assessed.     

准双曲面齿轮振动噪声试验与预估分析研究

为研究准双曲面齿轮传动机构的啮合振动、辐射噪声与传动误差的关系,建立三者之间的数据同步检测模型;并利用Y9550型锥齿轮滚动检验机搭建了综合试验平台。通过对一副准双曲面齿轮的振动与噪声信号的采集数据对比,分析振动与噪声的时域特征,并进一步分析振动与噪声谱中的频域相关特性。在Kato公式的基础上引伸出准双曲面齿轮的定量分析式,并借助传动误差的检测结果,对多次采集的数据进行以振动代替噪声的预估计算,试验结果表明:准双曲面齿轮的啮合振动能够较准确地反映出传动噪声的状态,并能够反馈到齿轮设计层面上,从而达到降低齿轮振动与噪声的目的,提高传动系统的稳定性。     

A genuine face milling cutter geometric model for spiral bevel and hypoid gears

Accurate tooth surface and good surface quality are critical to achieve the low-noise bevel gear drives. Face milling, traditionally works as tooth roughing process, can now possibly be used for finishing process because its high speed can produce good tooth surface quality. But with the previous simplified cutter geometric model in tooth modeling, the high accurate tooth surface cannot be obtained. In this paper, a genuine face milling cutter geometric model for spiral bevel and hypoid gears is proposed. This model exactly matches with the cutter geometry in the industrial application when not considering the fabrication tolerances and tool wear . In the modeling, the blades of the genuine cutter are parameterized with blade angle, rake angles, and relief angles. The side and circular cutting edges of blades are represented on the blade rake plane, rather than the normal plane as the simplified cutter geometry. The mathematic model of the genuine tool profiles on the normal plane is derived. It can be conveniently used by the existing tooth modeling program and easily customized by specifying the geometric parameters. In comparison with the genuine tool profile with the simplified tool profile, the big geometric errors of the simplified blade profile are founded, which proves that the genuine cutter geometric model is correct and essential.     

螺旋锥齿轮数字化闭环制造的主要功能模块及其实现

基于中心计算机、国产齿轮测量中心和四轴联动数控铣齿机,将齿面的数控展成、数字化检测、计算机数值处理及数字化反调修正有机组合,构建了螺旋锥齿轮数字化闭环制造系统.实际应用表明,该系统能有效控制齿面几何精度与啮合质量,齿面质量稳定,加工效率高.     

展成法大轮准双曲面齿轮点啮合齿面主动设计

为准双曲面齿轮传动点啮合齿面主动设计建立通用的技术平台对于方便点啮合齿面主动设计的实际应用和更加深入的锥齿轮技术研究都是一项重要的基础工作.基于三轴联动锥齿轮机床建立准双曲面齿轮展成法大轮齿面的通用数学模型.根据点啮合齿面主动设计的原理和方法,在大轮轴截面内描述空间齿面啮合的接触点迹线,推导得到了展成法大轮点啮合齿面主动设计所需要的具体计算公式.这些公式可用于不同展成型式的展成法大轮点啮合齿面主动设计.最后,给出了一个展成法大轮准双曲面齿轮传动点啮合齿面主动设计的算例.     

The effect of fluid properties and geometrical parameters of cantilever on the frequency response of atomic force microscopy

Nowadays, the atomic force microscopy plays an indispensable role in imaging and manipulation of biological samples. To observe some specific behaviors and biological processes, fast and accurate imaging techniques are required, and one way to speed up the imaging process is to use short cantilevers. For short beams, the Timoshenko model seems to be more accurate compared to other models such as the Euler–Bernoulli. By using the Timoshenko beam model, the effects of rotational inertia and shear deformation are taken into consideration. In this paper, the frequency response of a rectangular atomic force microscope (AFM) in liquid environment has been analyzed by using the Timoshenko beam model. Afterward, since the dynamic response of AFM is influenced by the applied medium, the effects of physical and mechanical properties (e.g., fluid density and viscosity) on the frequency response of the system have been investigated. The frequency responses of the AFM cantilever immersed in various liquids have been compared with one another. And eventually, to study the influence of geometry on the dynamic behavior of AFM, the effect of the cantilever's geometrical parameters (e.g., cantilever length, width and thickness) on the frequency response of the system has been studied.