螺旋的共轭轴理论及其应用

本文提出了两螺旋公共共轭轴线偶及其解析计算公式,论证了螺旋面上螺旋辐射线投影及其几何意义。证明元柱蜗杆、蜗轮的“啮合轴”正是蜗杆齿面螺旋和蜗轮、蜗杆相对瞬时运动螺旋的公共共轭轴线偶。蜗杆、蜗轮齿面的接触线是公共共轭轴线偶之一,在蜗杆螺旋齿面上的正投影。证明滚切齿轮(包括渐开线和非渐开线、直齿和斜齿)时存在一啮合极点和极平面。滚刀和齿轮的接触点在确定的极平面上,是啮合极点在齿面上的正投影。为应用空间啮合原理精确设计、研究滚刀,提供了几何模型和新的简便而精确的计算方法。     

蜗杆齿厚的坐标测量法

针对蜗杆齿厚传统测量方法精度低或操作复杂的缺陷,提出了使用三坐标测量机精确、快速检测蜗杆齿厚的方法.在阐述该方法测量原理和测量步骤的基础上,用实例加以验证并对测量结果进行了精度分析.测量实践表明,该方法具有测量准确度高、简便易行的优点,较好地解决了高精度测量蜗杆齿厚的问题.     

渐开线蜗杆副的蜗轮M值计算公式

本文根据蜗杆的渐开螺旋面方程，利用其与蜗轮的啮合方程和钢球接触点的法线方程，推导出蜗轮的M值计算公式。     

不正确的计算式《蜗轮分度圆齿厚 S_(fn)和实测值 M 的关系》一文之我见

因处理有关蜗轮测量技术问题,拜读了《齿轮测量技术短文选编》(《计量技术》编辑部编,中国计量出版社1986.5出版)一书中的《蜗轮分度圆齿厚 S_(fn)和实测值 M 的关系》(下称“关系”)一文。笔者认为,该文疑误之处甚多,所介绍的计算式并不正确,特提出自己的看法与作者商榷,并就教于专家和读者们。     

基于精确齿面建模的ZA蜗杆蜗轮有限元接触分析

为了研究不同情况下蜗杆蜗轮间的接触应力和蜗杆扭转角与驱动力矩之间的关系,根据齿面方程建立具有精确齿面的ZA蜗杆蜗轮实体模型,利用ANSYS对此模型在同一载荷不同啮合位置和同一啮合位置不同载荷条件下进行有限元接触分析,研究在一个轮齿啮合周期内,各啮合齿对的接触应力分布和载荷在不同齿对上的分配情况.分析结果表明:理论接触应...     

快速综合检测多头蜗杆螺旋槽用工作量规

在机加工中,多头蜗杆一般采用螺纹千分尺和齿厚卡尺综合测量,检测繁琐,效率低。我厂生产的泰山12型方向机蜗杆,生产批量大,如不解决快速测量,要提高生产效率是不可能的。为此,我们设计了蜗杆螺旋槽快速综合检测工作量规(图3),直接应用于生产加工过程。经多年使用,取得了良好的效果。使用时先将平尺与蜗杆外圆靠平,然后用量规测量、试其通止,判断工件是否合格。现将工作量规的计算过程介绍如下。表1图1图2是蜗杆的基本参数。一、工作量规基本尺寸1.螺旋槽各参数计算(l)轴向螺距Ta(3)定齿高法向槽宽Fa (6)槽侧与顶径素线的内接圆直径Dn 2.工…     

蜗杆和齿轮的轴向齿厚Sx法向弦齿厚Sn的精确计算

本给出了当齿厚存在减薄量和制造允差时，蜗杆和齿轮的轴向齿厚Ｓｘ，法向弦齿厚Ｓｎ的精确计算方法和适用的近似公式。     

精密分度蜗轮跨齿补点测量法的研究

一分度蜗轮副是滚、插齿机的心脏,它决定着滚、插齿机的精度和齿轮加工质量。精度高于5级的分度蜗轮副需要用动态精度指标切向综合误差△F＇_i来衡量,这就需要单啮仪等动态测量设备来测量。在没有这些仪器时,可用周节累积误差△F_P,的测量来代替。对于模数 m=1～10,直径D=380mm,齿数小于100的蜗轮可直接用万能测齿仪以相对法测量,对于精度要求较高齿数>100,直径>380mm的蜗轮借助于圆转台及测齿仪测量托架组合装置用跨齿补点法测量。所谓跨齿测量就是指用比较法测量蜗轮周节时,测齿仪的两测量爪跨的齿数不少于两个,显然跨齿测量得到的周节累积误差小于单齿测量的累积误差,因此须进行补点,予以校     

CNC齿轮测量中心对蜗杆啮合误差的检测与分析

根据圆柱蜗轮蜗杆啮合特点，探讨了利用CNC齿轮测量中心实现蜗杆啮合误差的检测，并提出具体的检测实施方案以及啮合误差的计算方法，在此基础上使用VS．NET开发了测量和计算软件，验证了此方案的可行性和正确性。     

车削的圆弧齿圆柱蜗杆的M值计算

蜗杆齿厚的测量方法之一是测量M值,该测量方法准确而方便。本文就车削的圆弧齿圆柱蜗杆的M值计算公式进行推导。车削蜗杆3时,车刀2原始安装位置如图1所示。该图是蜗杆的一个轴截面。由图1可得a和b之值: 图2示出了坐标o_ux_uy_uz_u和o_1x_1y_1之间的相对运动关系,即车刀和蜗杆之间的相对运动关系。当坐标系o_ux_uy_uz_u(与车刀相固连)     

Two-stage optimum design of the dual-lead worm

The dual-lead worm and worm gear drive is a convenient anti-backlash mechanism. It can be used in precision machine tools and indexing tables. The objective is to minimize the frictional force between the worm and the gear. The constraints include the worm geometry, stresses, displacements and the natural frequency of the worm. To avoid a difficult 3-D shape optimization problem, a two-stage optimization method is introduced in this paper. The first stage optimization uses an approximate worm model. The threads of the worm are approximated by plate elements in this stage. The design variables are pitch diameter of the worm, the module of the gear and the difference of the left and the right modules. The second stage optimization uses a true 3-D solid model with continuous spiral threads to determine the optimum shape of worm threads. Examples show the approach is feasible and efficient.     

蜗杆砂轮磨齿机几何误差敏感度分析

为识别影响蜗杆砂轮磨齿机空间精度的关键几何误差项,提出一种基于旋量理论和Sobol法的几何误差敏感度分析方法。以YW7232型蜗杆砂轮磨齿机为研究对象,首先,基于旋量理论建立机床的几何误差模型;然后,采用Sobol法计算机床磨削过程中各几何误差项对空间误差分量的敏感度系数,并识别出关键几何误差项;最后,对机床的关键几何误差项进行修正,通过仿真分析对比修正前后机床的空间误差分量以及3种测量模式下球杆仪的杆长。仿真结果表明所提出的方法可有效识别出机床磨削过程中的关键几何误差,这可为提高机床精度提供理论指导。     

Effect of installation errors on beveloid gears’ precision ground by cone-shape worm wheel

Forschung im Ingenieurwesen - Both the mathematical model of a cone-shape worm wheel and the mathematical model of cone-shape worm wheel grinding beveloid gears with installation errors of...     

Curvature interference characteristic of conical surface enveloping conical worm

The theory to distinguish whether the curvature interference happens or not is well established for the enveloping conical worm. Some important results, such as the meshing function, the equation of the enveloping conical worm helicoid, and the curvature interference limit function, are all obtained. The foundation of computing the curvature interference limit line is to solve the system of nonlinear equations. A technique based on the elimination method and the geometric construction is proposed, which can be employed to study the existence of the solution of a system of nonlinear equations and to solve all the solutions of this system within the given solving domain. By means of the theory and technique brought forward, it is discovered that there usually are two curvature interference limit lines separately on each side of a tooth of an enveloping conical worm. When the number of the enveloping conical worm threads is smaller, the curvature interference in general does not happen on the both sides of a tooth. The avoiding mechanism of the curvature interference is that the limit line does not exist during the real cutting mesh because the limit line is inside the entity of the enveloping conical worm and its conjugate line is outside the entity of the grinding wheel. The numerical outcome shows that, the toe on the \(e\) flank has the greatest potential risk to be subjected to the undercutting.     

平面二包环面蜗杆参数化精准建模研究

平面二包环面蜗杆具有许多优点,实体建模有助于其设计与分析.通过分析齿轮啮合原理,推导出平面二包环面蜗杆齿面方程及平面方程.利用微增量原理,求出蜗杆的交线方程.利用VB,Matlab和Solidworks软件结合所推导公式进行联合编程开发,建立了平面二包环面蜗杆的实体参数化建模系统.同时推导误差解析法计算公式,对软件建模实例进行误差分析,结果证明该建模方法是有效、可行的.该方法使得平面二包环面蜗杆复杂的建模过程简单化,提高了设计效率,有利于平面二包环面蜗杆的推广使用.     

基于多特征相似度的蠕虫检测

在分析了正常网络流量分布的基础上,提出了基于多特征相似度的蠕虫检测方法。首先利用多个特征的高频统计结果分别计算相似度,然后将它们复合成一个相似度值,接下来比较相邻两次的相似度,最终发现异常。这种方法可以在一定程度上降低检测的误报率和漏报率,对蠕虫在大规模蔓延之前的检测效果也比较理想,可以在蠕虫爆发的早期阶段做出诊断,并且它不但可以用于已知类型的蠕虫检测而且对未知类型的蠕虫也有较好的检测效果。     

轮对几何参数及踏面缺陷光电检测方法

提出了一种基于光电检测技术的车辆轮对综合参数自动检测方法。运用精密激光位移传感、CCD及数字图像处理技术,实现了轮缘厚度、轮缘高度、车轮直径等尺寸参数的非接触自动检测;再结合精密运动控制,以及车轴和圆周方向的快速激光扫描,实现了踏面擦伤和剥离等缺陷参数的分类和识别。实验结果表明,基于上述测量方法的检测系统,其尺寸参数测量精度为0.2mm,擦伤深度测量精度为0.1mm,剥离长度测量精度为0.5mm,能满足车辆段修现场使用的要求。     

Bivariate tolerance design for lock wheels by considering quality loss

In the design of tolerance allocation the cost–tolerance function is usually employed to represent the objective function which is to be minimized. The traditional cost–tolerance functions in the literature are concerned with only one characteristic. In this paper we obtain a bivariate cost–tolerance function to describe the relationship between the cost and tolerances of two characteristics (i.e. the thickness and inner diameter) of a lock wheel. Then the bivariate loss function is combined with the bivariate cost–tolerance function to determine the optimal tolerances for the thickness and inner diameter of a lock wheel such that the user's potential loss/cost may be evaluated. When the quality loss is considered, the tolerances of both characteristics become tighter. By including the effect of product degradation, the present work of expected bivariate quality loss is then introduced as a quality performance measure. By assuming linear drifts on both the thickness and inner diameter of the lock wheels, the model with the present worth of quality loss leads to tighter tolerances of both characteristics. In addition, a longer planning horizon (or a longer useful life of the product) leads to tighter tolerances and a larger user's discount rate results in looser tolerances for both characteristics. Copyright © 2000 John Wiley & Sons, Ltd.     

阻尼车轮减振参量的有限元仿真与优化设计

为有效抑制车轮振动噪声,弥补现场试验的不足,在对黏弹性阻尼材料阻尼机理研究的基础上,以S1002CN型面高速动车组车轮为分析对象,采用正交试验设计和ABAQUS有限元仿真计算相结合的方法,对阻尼车轮减振性能进行仿真优化设计,得出阻尼车轮3个主要参数对其踏面径向振动加速度影响的主次顺序和显著性,并能快速确定阻尼车轮结构参数的最优组合为:阻尼层厚度4 mm、约束层厚度1.5 mm、约束阻尼层敷设于车轮两侧。研究结果表明,黏弹性约束阻尼技术是抑制车轮高频振动的有效手段,对于黏弹性阻尼材料在低噪声车轮中的运用具有一定的理论和实际应用价值。     

Continuous generating grinding method for beveloid gears and analysis of grinding characteristics

Continuous generating grinding has become an important gear processing method owing to its high efficiency and precision. In this study, an adaptive design model is proposed for the continuous generation of beveloid gears in common gear grinding machines. Based on this model, a method for determining the installation position and grinding kinematics is developed alongside an analytical meshing model for grinding contact trace and derivation of key grinding parameters. By combining these aspects, a general mathematical model for the continuous generation of beveloid gears is presented, comprising the entire grinding process from worm wheel dressing to the evaluation of grinding deviation. The effects of the worm and dressing wheel parameters on the grinding deviation were analysed, facilitating the development of an approach to improve the grinding accuracy. The presented procedure represents a novel design method for the continuous generation of beveloid gears in common gear grinding machines, facilitating the appropriate selection of worm and dressing wheel parameters.The full text can be downloaded at https://link.springer.com/article/10.1007/s40436-022-00388-z