变位齿轮在直升机传动系统中的应用研究

为了研究变位齿轮在直升机传动系统中的应用,以一对大传动比的直升机齿轮对为例,研究变位系数对齿轮的齿根滑动系数和重合度的影响,并讨论变位和非变位齿轮的接触应力、弯曲应力变化情况。结果表明,变位处理可以使齿根滑动系数接近,同时对重合度影响较小,降低了齿轮的接触应力和弯曲应力。     

插切外齿轮齿形系数的数学模型及影响因素的研究

本文针对插切加工外齿轮齿形系数研究现状不足 ,利用相对运动原理推导出插切外齿轮齿根过渡曲线和齿形系数的数学模型。讨论插齿刀齿数、变位系数、齿顶圆角半径和相啮合齿轮的齿数、变位系数对插切外齿轮齿形系数的影响 ;同时比较插切加工与滚切加工齿轮齿形系数的不同 ,得出插切加工大变位齿轮齿形系数较滚切加工小 ,而对于小变位齿轮则情况相反。因此对于插切加工大变位齿轮有利于提高齿轮弯曲强度。     

齿轮变位系数与齿轮各系数和尺寸之间变化关系探讨

主要探讨齿轮变位系数的大小与齿轮各系数、尺寸之间的变化关系,以便于为变位齿轮及变位齿轮传动的研究和尺寸计算以及变位系数的选择提供依据.     

渐开线直齿圆柱齿轮变位系数极值的研究

用变位齿轮无侧隙啮合方程、齿顶厚为零及重合度计算公式推导出了单位变位系数和、单位中心距变动系数、单位齿项高变动系数、最大变位系数、齿轮变位系数求解公式,并研究了变位系数的分配公式.     

点线啮合齿轮变位系数的研究

为了避免根切,根据点线啮合齿轮、特点及啮合的基本定律,研究了点线啮合齿轮通用无侧隙啮合方程、直齿点线啮合齿轮和斜齿点线啮合齿轮最小变位系数计算公式。以一实例来阐述点线啮合齿轮中大齿轮变位系数的计算过程,整个计算过程通过软件完成。得出点线啮合齿轮无侧隙啮合方程,及最小变位系数计算同渐开线圆柱齿轮类似、点线啮合齿轮应计算最小变位系数、只能在封闭图中才能准确地确定大齿轮变位系数和螺旋角等3个结论。     

大变位齿轮变位系数的可视化设计

介绍了大变位齿轮的特点，变位系数的设计准则。采用计算机可视化方法设计大变位齿轮变位系数，此方法实用、可靠，适合工程应用。     

变位系数齿轮加工的研究

根据齿轮传动原理,通过对标准齿轮与变位齿轮的加工研究,得出了超大变位系数的齿轮不能用标准的齿轮滚刀加工,采用绘图软件画出变位齿轮的齿形样板,制作指状刀,可以在滚齿机、镗床上加工超大变位系数齿轮,此方法得到了验证。     

基于Matlab的渐开线少齿差行星齿轮变位系数取值方法研究

根据少齿差行星齿轮传动的定义可知,变位系数的取值是少齿差行星齿轮减速器设计的关键;通过分析和对比常用变位系数选取方法,基于变位齿轮变位系数选择的限制条件理论,并使用Matlab软件进行辅助计算,提出了一个渐开线少齿差行星齿轮变位系数的取值方法;实例验证得到Matlab编程比常规设计计算出的外齿轮变位系数小但重合度却大,结果表明Matlab编程可行性较高。     

少齿数齿轮变位系数的精确选择

为了提高少齿数齿轮副的抗胶合能力和耐磨损的能力,结合少齿数齿轮传动的特点和各参数之间的关系,考虑了螺旋角和侧隙对变位系数的影响,推导了齿轮有侧隙啮合方程,确定变位系数总和;以等滑动率作为分配条件,以变位系数基本限制条件作为约束条件,利用MATLAB软件编写程序实现了少齿数齿轮副变位系数的数值选取。程序选取普通齿轮的变位系数与经典变位系数图谱对比结果表明:该程序不仅可以实现少齿数齿轮副变位系数的精确数值选择,而且可实现普通正变位齿轮副的变位系数的选取,为少齿数齿轮的深入研究和推广提供了参考依据。     

大模数圆柱渐开线齿轮副变位系数的控制

从大模数圆柱渐开线齿轮副齿形尺寸偏差对变位系数和滑动率的影响分析入手,阐述了通过设计和制造双重控制变位系数的新理念。介绍了设计过程中齿轮总变位系数的分配方法和制造过程中变位系数搭配控制方法。通过计算和数据分析,得出结论:基于计算机编程设计,可求得总变位系数分配的优化值,使理论滑动率差极低(Δη≤0.0001);通过制造过程中变位系数搭配控制,可以减小齿形尺寸偏差对变位系数和滑动率的影响,使实际滑动率差大幅度降低;采用变位系数搭配控制方法制造齿轮副,可增加参数配对检验项目。     

加工大模数、大变位齿轮用双头滚刀的设计与应用

介绍了加工大模数、大变位齿轮的大直径双头滚刀的设计要点及实际应用效果。     

三轴式内齿行星齿轮减速器动载系数的研究

考虑了齿轮啮合刚度、啮合阻尼以及各支承轴承、行星轴承的刚度,推导出了系统的变形协调关系,通过集总参数法建立了三轴式内齿行星齿轮减速器的弹性动力学模型,求解出了不同内齿板结构下,系统的动载系数。结果表明:具有三相内齿板减速器的动载系数最小,具有一相内齿板的减速器动载系数最大;具有三相内齿板的减速器可以在较高的转速场合下使用。     

Dynamic interaction between contact loads and tooth wear of engaged plastic gear pairs

This study investigates the interaction between the dynamic contact load and the tooth profile wear of POM and Nylon 66 plastic gear pairs. A dynamic model of a plastic gear pair is presented. This model incorporates the effects of position-varying tooth mesh stiffness, damping ratio, load sharing, tooth profile wear and temperature on the dynamic contact load. The tooth wear equation developed by Flodin and Andersson [Simulation of mild wear in spur gears. Wear 1997;207:16–23] is utilized to simulate tooth wear and tooth profile variation. The variation of the contact load generated by the cumulative tooth profile wear is simulated and examined. A computational algorithm is developed to simulate the interaction between a dynamic contact load and tooth profile wear. Numerical results demonstrate that the dynamic load histogram of an engaged plastic gear pair can change markedly due to tooth wear.     

含误差的直齿轮的齿廓修形

依据齿轮传动载荷与轮齿变形的关系,推导出定载荷条件下,修形直齿轮静态传动误差与齿对综合修形参数的关系表达式。提出含制造误差修形齿轮修形参数的确定原则:理论设计修形齿轮的最大综合修形量应能消除含误差齿廓轮齿在啮入和啮出位置产生的几何干涉,理论设计修形齿轮的静态传动误差应保持最小的变化。给出了合制造误差修形直齿轮修形参数的计算公式,阐述了相应的确定方法。系统动态响应计算表明该方法所获得的修形齿轮具有良好的减振效果。     

一种确定内啮合和外啮合斜齿圆柱齿轮载荷分布的有效方法

为了能精确地进行斜齿圆柱齿轮的强度计算和振动分析,必须准确地确定斜齿圆柱齿轮接触线上的载荷分布。本文根据齿面坐标系及相应的坐标转换阵,提出了一种有效地计算内啮合和外啮合斜齿圆柱齿轮载荷分布的方法。通过总体坐标系可同时求出斜齿圆柱齿轮在整个啮合过程中诸接触线上的载荷分布和齿间载荷分配,这将极大地节省计算时间。文末给出了计算实例。     

Contact stress calculation of undercut spur and helical gear teeth

The presence of undercut at the pinion root may affect the load sharing among couples of spur gear teeth in simultaneous contact, as well as the load distribution along the line of contact of helical gears. This occurs if the outside points of the wheel profile do not find, due to undercut, mating profile to mesh with, which is called vacuum gearing. Under these conditions, the effective contact ratio is reduced, and the critical contact points may be shifted from their locations at non-undercut profiles. In this paper, a non-uniform model of load distribution along the line of contact, obtained from the minimum elastic potential criterion, has been used combined with the Hertz equation for the calculation of the contact stress. A complete study on the critical load conditions and the value of the critical contact stress has been carried out, considering a wide range of the values of the geometrical parameters. As a result, a recommendation for pitting load capacity calculations of vacuum-gearing spur and helical gears is proposed.     

Dynamic loading of spur gears with linear or parabolic tooth profile modifications

A computer simulation was conducted to investigate the effects of both linear and parabolic tooth profile modification on the dynamic response of low-contact-ratio spur gears. The effect of the total amount of modification and the length of the modification zone were studied at various loads and speeds to find the optimal profile modification for minimal dynamic loading.

Design charts consisting of normalized maximum dynamic load curves were generated for gear systems operated at various loads and with different tooth profile modification. An optimum profile modification can be determined from these design charts to minimize the dynamic loads of spur gear systems.     

NGW行星齿轮典型机构的均载性能分析

本文通过对采用浮动构件的行星传动机构与采用非浮动构件的行星传动机构进行对比研究,利用测定行星齿轮轴的变形情况来推断均载情况的方法,对比两种结构的均载性能,并将测得的应变曲线通过FFT频谱分析仪进行频谱分析,得出各阶频谱值,再把减速器各零件的误差传动频率与之相比较,从中得出各种因素对均载性能的影响程度,以便对结构设计提出改进可靠依据。     

发动机激励下车辆传动系统动载研究

发动机激励下的传动系动载是引起轴和齿轮损坏、断裂的主要原因,文中将传动系轴段上的动载分为轴段附加转矩和平均转矩两部分,根据传动系扭振的轴段角似移响应,推导发动机激励下轴段和齿轮动载的理论计算公式,并给山判断传动系统齿轮齿面敲击的方法。以某车辆传动系为算例,进行发动机激励下系统动载计算和试验验证,分析传动系中盖斯林格弹性联轴器的减振效果。旨在对传动系载荷特性进行预测,为系统的动力学设计或改进提供理论依据。     

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.