三坐标测量机上实现圆锥度误差测量和评价

本文叙述了在三坐标测量机上测量圆锥度误差的基本原理,提出自适应非线性最小二乘法评定圆锥度误差的方法,并阐述了最小二乘法与最小条件评定法的数学模型。对于最小条件法,介绍了两种最优化算法,其中对单纯形法,本文提出适合形状误差评定的初始单纯形边长和迭代终止准则的选择方法。通过实际测量和计算表明,圆锥度误差评定值不仅与算法的选择有关,而且与测量点数的多少有关。     

圆锥滚子轴承滚道面圆度误差的精密测量与分析

提出了一种基于Primar MX4多功能综合测量机和Mar。Mess语言的圆锥滚子轴承滚道面圆度误差精密测量方法。根据最小二乘法评价原理,分析了锥面圆度测量的调心调平、测头对中和测速的影响,重点分析了测力对测量误差的影响,并给出了具体的MarMess编程语言实现过程,最后通过多组实测数据,得出了圆锥滚子系列轴承滚道面圆度误差的最佳测力为0.1 N。     

重型机械圆锥齿轮的齿形分析

圆锥齿轮的轮齿有直齿、曲齿2种类型。与直齿圆锥齿轮相比,曲齿圆锥齿轮齿面的相对曲率半径较大,承载能力高;轴向重和度大,传动平稳;齿面局部接触对误差敏感性小。所以,曲齿圆锥齿轮应用广泛。     

新型立式同轴度锥面检具设计

介绍了一种同轴度测量方法,采用锥面和圆锥滚子定位来测量内孔的同轴度,同时可以测量孔与孔、孔与轴的同轴度。该检具结构简单、零件少,减少了零件累加误差对同轴度检测的影响,能够准确、快捷地测出同轴度的实际误差。     

锥度测量装置

图示测量装置用于测量由平面与圆锥面构成锥角的锥体零件,主要测量锥角α误差的线性值和锥体母线的平直度误差。 测量装置的球形测量触头使用于锥体5的平面一边,而刀状测量触头则使用于锥体5的圆锥     

精密离心机主轴回转精度的仿真

首先给出了气体静压轴承承载能力及刚度随偏心量变化曲线;并在此基础上应用动力学仿真软件仿真了静不平衡、主轴铅垂度误差以及二者综合作用下的精密离心机主轴运动模式及其引起的径向回转误差和失准角。研究表明,当静不平衡与回转中心在同一水平面内时,精密离心机主轴做圆柱运动;静不平衡量存在轴向偏移或存在主轴铅垂度误差时,主轴做圆锥运动,并且失准角随静不平衡量和铅垂度误差增大而增大;二者综合作用时主轴做圆锥运动,引起的径向回转误差和失准角由二者共同决定。研究结果有助于验证前人对精密离心机主轴运动模式的理论分析,并计算不同工况下径向回转误差和失准角。     

考虑内圈挡边表面波纹度的圆锥滚子轴承振动特征研究

表面波纹度是圆锥滚子轴承滚道表面的主要形状误差之一。针对圆锥滚子轴承内圈挡边表面波纹度诱发的时变激励机理和动力学建模的问题,考虑流体动力润滑油膜与轴承轴向和径向变形耦合激励作用的影响,提出考虑时变激励的圆锥滚子轴承挡边表面波纹度动力学模型,并通过试验结果验证模型的有效性;研究内圈挡边表面波纹度时变激励下的圆锥滚子轴承的振动响应特征;分析内圈挡边表面波纹度幅值和阶次对圆锥滚子轴承振动响应特征的影响规律,解决圆锥滚子内圈挡边波纹诱发的时变激励及其动力学建模问题,为获得准确的含内圈挡边表面波纹度的圆锥滚子轴承的动力学响应特征提供新的手段和方法。结果显示,轴承的振动水平随着内圈挡边表面波纹度幅值的增大逐渐加剧;内圈挡边表面波纹度会改变轴承振动加速度响应频谱的峰值频率;当内圈挡边表面波纹度的阶次为滚动体数目的整数倍时,圆锥滚子轴承振动值将出现峰值。因此,控制内圈挡边表面波纹度的幅值与阶次将有利于抑制圆锥滚子轴承的振动水平。     

精密圆锥滚子轴承内滚道圆度误差的控制

对精密圆锥滚子轴承滚道磨加工产生的圆度误差的因素进行了综合分析,并据此总结出了一套行之有效的解决办法,对确保轴承的旋转精度具有重要意义。     

双圆锥前刀面插齿刀的设计

本文提出了一种双圆锥前刀面的新型插齿刀，它克服了标准括齿刀无法解决的采用合理切削角度与齿形误差增大之间的矛盾，从而使插齿生产率与精度都得到相应提高。     

盲孔的研磨

图1所示为我厂某油缸体盲孔。该工件材料为CrMoCu,要求孔的圆度及圆锥度误差均不大于0.01mm。我厂用镗孔后研磨法实现了该盲孔的各项技术指标。这里对镗孔要求、研具、研磨剂等作些简单介绍.     

Conicity error evaluation using sequential quadratic programming algorithm

Form error evaluation plays an important role in processing quality evaluation. Conicity error is evaluated as a typical example in this paper based on sequential quadratic programming (SQP) algorithm. The evaluation is carried out in three stages. Signed distance function from the measured points to conical surface is defined and the cone is located roughly by the method of traditional least-squares (LS) firstly; the fitted cone and the measured point coordinates are transformed to simplify the optimal mathematical model of conicity error evaluation secondly; and then optimization problem on conicity error evaluation satisfying the minimum zone criterion is solved by means of SQP algorithm and kinematic geometry, where approximate linear differential movement model of signed distance function is deduced in order to reduce the computational complexity. Experimental results show that the conicity error evaluation algorithm is more accurate, and has good robustness and high efficiency. The obtained conicity error is effective.     

Measurement uncertainty evaluation of conicity error inspected on CMM

The cone is widely used in mechanical design for rotation, centering and fixing. Whether the conicity error can be measured and evaluated accurately will directly influence its assembly accuracy and working performance. According to the new generation geometrical product specification(GPS), the error and its measurement uncertainty should be evaluated together. The mathematical model of the minimum zone conicity error is established and an improved immune evolutionary algorithm(IIEA) is proposed to search for the conicity error. In the IIEA, initial antibodies are firstly generated by using quasi-random sequences and two kinds of affinities are calculated. Then, each antibody clone is generated and they are self-adaptively mutated so as to maintain diversity. Similar antibody is suppressed and new random antibody is generated. Because the mathematical model of conicity error is strongly nonlinear and the input quantities are not independent, it is difficult to use Guide to the expression of uncertainty in the measurement(GUM) method to evaluate measurement uncertainty. Adaptive Monte Carlo method(AMCM) is proposed to estimate measurement uncertainty in which the number of Monte Carlo trials is selected adaptively and the quality of the numerical results is directly controlled. The cone parts was machined on lathe CK6140 and measured on Miracle NC 454 Coordinate Measuring Machine(CMM). The experiment results confirm that the proposed method not only can search for the approximate solution of the minimum zone conicity error(MZCE) rapidly and precisely, but also can evaluate measurement uncertainty and give control variables with an expected numerical tolerance. The conicity errors computed by the proposed method are 20%-40% less than those computed by NC454 CMM software and the evaluation accuracy improves significantly.     

弧齿锥齿轮小轮锥度切削原理及其仿真

介绍了弧齿锥齿轮锥度切削的加工方法和切齿原理;根据局部综合法建立了小轮实现锥度切削的加工条件;利用TCA分析对锥度切削齿面啮合质量进行了仿真;利用三维软件Pro/E,绘制出了小轮锥度切削的三维轮齿模型;证明了在数控铣齿机上实现锥度切削的可行性。     

给定锥度的锥形度最小二乘评定法

给出了圆锥面锥形度的定义，介绍了给定锥度的锥形度最小二乘评定计算方法。     

Determination of efficient conicity of the working walls of the crystallizer of a continuous billet casting machine

A procedure of calculation of efficient conicity of the crystallizer of a continuous billet casting machine is developed. At efficient conicity, close contact of the ingot with the working wall is ensured and heat exchange is intensified over the entire height of the crystallizer. The choice of conicity should be carried out taking into account ingot shrinkage during solidification. In the suggested mathematical model, processes of shrinkage, solidification, and heat exchange are interrelated.     

A reliable method of minimum zone evaluation of cylindricity and conicity from coordinate measurement data

The form error evaluation of cylinders and cones is very important in precision coordinate metrology. The solution of the traditional least squares technique is prone to over-estimation, as a result unnecessary rejections may be caused. This paper proposes a reliable algorithm to calculate the minimum zone form errors of cylinders and cones, called a hybrid particle swarm optimization-differential evolution algorithm. The optimization is conducted in two stages, so that the program can hold a fast convergence rate, while effectively avoiding local minima. Experimental results demonstrate that the proposed algorithm can obtain very accurate and stable results for the calculation of cylindricity and conicity.     

Influence of vehicle parameters on critical hunting speed based on Ruzicka model

While introducing foreign advanced technology and cooperating with Chinese famous research institutes,the high-speed vehicles are designed and take the major task of passenger transport in China.In high-speed vehicle,the characteristic of shock absorber is an important parameter which determines overall behavior of the vehicle.The most existing researches neglect the influence of the series stiffness of the shock absorber on the vehicle dynamic behavior and have one-sided views on the equivalent conicity of wheel tread.In this paper,a high speed passenger vehicle in China is modeled to investigate the effect of the parameters taking series hydraulic shock absorber stiffness into consideration on Ruzicka model.Using the vehicle dynamic model,the effect of main suspension parameters on critical speed is studied.In order to verify the reasonableness of shock absorber parameter settings,vibration isolation characteristics are calculated and the relationship between suspension parameters and the vehicle critical hunting speed is studied.To study the influence of equivalent conicity on vehicle dynamic behavior,a series of wheel treads with different conicities are set and the vehicle critical hunting speeds with different wheel treads are calculated.The discipline between the equivalent conicity of wheel tread and critical speed are obtained in vehicle nonlinear system.The research results show that the critical speed of vehicle much depends on wheelset positioning stiffness and anti-hunting motion damper,and the series stiffness produces notable effect on the vehicle dynamic behavior.The critical speed has a peak value with the equivalent conicity increasing,which is different from the traditional opinion in which the critical speed will decrease with the conicity increasing.The relationship between critical speed and conicity of wheel tread is effected by the suspension parameters of the vehicle.The study results obtained offer a method and useful data to designing the parameters of the high speed vehicle and simulation study.     

Experimental investigation of surface and geometrical characteristics of rotary ultrasonic drilling of soda glass

Edge-chipping, surface roughness and dimensional accuracy are crucial quality aspects of drilled holes in hard-to-cut material such as glass, ceramics and carbon fiber reinforced plastics. In this article, an experimental study was conducted to investigate the quality measures of holes produced by rotary ultrasonic drilling (RUD) and conventional drilling. Edge-chipping width at tool exit side, the surface roughness (Ra and Rz), out-of-roundness, cylindricity error and hole conicity were the main responses when drilling soda glass using diamond abrasive tools and a cutting fluid. Statistically designed experiments were carried out for rotary ultrasonic and conventional drilling (CD) at two levels of tool feed rate (0.6 and 6?mm/min), spindle speed (3,000 and 8,000?rpm) and tool particles-concentration. Analysis of variance was used to define the significant factors and their interactions and build models for predicting the responses. The results showed that reducing the chipping, surface roughness and roundness error. The normal tool concentration showed a substantial effect in improving the surface quality and reducing the hole-geometrical errors.     

抗蛇行减振器参数对车辆稳定性的影响分析

介绍了抗蛇行减振器的简化模型——Maxwell模型。基于蛇形运动的稳定性理论,推导了带抗蛇行减振器的刚性转向架的线性临界速度解析表达式。利用表达式研究了不同等效锥度下抗蛇行减振器串联刚度和结构阻尼对临界速度的影响。研究结果表明:在相同锥度下,结构阻尼和串联刚度存在最佳匹配关系,小结构阻尼应配合小串联刚度,较大结构阻尼应配合较大串联刚度,大结构阻尼应配合大串联刚度;在满足结构阻尼和串联刚度匹配的大范围下,不同等效锥度应匹配不同的串联刚度和结构阻尼,小锥度应匹配较小的串联刚度和较大的结构阻尼,大锥度应匹配较大的串联刚度和较小的结构阻尼。     

成形联接轴／毂孔数控车削加工的研究

提出以高响应伺服刀架为基础，采用计算机控制技术和迭代学习控制策略，以车削的方法加工成形联接轴／毂孔；并对锥度1：20的成形联结中典型零件－三角形轴／毂孔进行了加工实验。实验结果表明，数控车削加工不仅可以获得很高的加工效率，同时也可以达到较高的精度。