基于齿面跟随技术的特大齿轮测量方法研究

Verification of super-large gears is an effective way of ensuring the manufacturing quality of gears and enhancing the yield rate of finished products. However, available super-large gear measuring equipments cannot meet the requirements for super-large gears in modern industries. This project puts forward a novel on-line method of measurement for super-large gears，in which gear tooth surface following technology is utilized to realize accurate measurement of the relative positions among gear tooth surface points on the super-large gear, the influence of location errors on measurement results are separated by adopting the method of combination of stable feature points and global matching through the use of measurement data of multiple gear tooth surfaces, position of the gear axis is then accurately calculated, the multiple local coordinate systems are then integrated into one absolute coordinate system, the evaluation models of gear tooth profile error and form error of helix are then established, and corresponding calculation methods and software are developed to realize the evaluation of errors for super-large gears. On the basis of theoretical analysis and numerical simulation, optimized design of structures of super-large gear measuring equipment is performed, errors are reasonably distributed, precise gear tooth surface following mechanism is developed, and super-large gear measuring system is set up to conduct experimental study in order to analyze the mechanism of error generation and error compensation methods. This project supplies a feasible method for the solution of the problem of on-line detection of super-large gears, and can solve the problem of verification of super-large gears in manufacturing processes in the fields of hydroelectric power plant, aircraft carrier, etc., enhancing the accuracy and quality product rate in super-large gear manufacturing.

特大齿轮的检定是保证齿轮生产质量，提高特大齿轮成品率的有效方法，但目前特大齿轮测量装置远不能满足现代工业对特大齿轮的精确检测要求。项目提出一种新的特大齿轮在线测量方法，利用齿面跟随技术实现特大齿轮上齿面点相对位置的精确测量，通过基于稳定特征点和全局匹配结合的方法，利用齿轮上多个齿面的测量数据分离相对定位误差，以消除其对测量结果的影响，实现被测齿轮轴心的精确计算和多齿绝对坐标换算，建立齿廓偏差和螺旋线偏差评定模型，并开发相应的计算方法和软件，实现特大齿轮误差的评定。项目在理论分析、数值模拟的基础上，对特大齿轮测量装置进行结构优化设计和误差合理分配，开发精密齿面跟随机构，搭建特大齿轮测量系统，进行实验研究，分析测量装置的误差产生机理及补偿方法。本项研究为解决特大齿轮在线检测提供了一种可行的方法，项目研究成果可解决水电站、航母等领域特大齿轮生产过程中的检定问题，提高特大齿轮制造的精度和合格率。

特大齿轮的检定是保证齿轮生产质量，提高特大齿轮成品率的有效方法。本项目提出一种基于齿面跟随技术的特大齿轮测量方法，其特点是利用稳定特征点和全局匹配结合的方法，根据齿轮上多个齿面的测量数据分离相对定位误差，实现被测齿轮轴心的精确计算和多齿绝对坐标换算，建立齿廓偏差和螺旋线偏差评定模型，实现特大齿轮误差的评定。为解决特大型齿轮测量中缺乏参照标准的问题，首先分析渐开线的形成过程，然后推导出渐开线圆柱齿轮左、右齿廓的坐标计算方法，最后通过对基本构造曲线的坐标旋转得到了渐开线圆柱齿轮的离散化模型。针对目前面临的大齿轮测量基准与加工、设计基准不统一的难题，在大齿轮的测量过程中，结合激光跟踪仪和齿轮测量装置，确定大齿轮的测量基准。将齿廓实测数据和理论渐开线齿廓数据统一于同一坐标系O-xyz后，根据最小二乘迭代方法得到齿轮几何中心。采用最小包容区域法对直径2000mm的大齿轮齿廓偏差进行仿真，其结果误差小于5μm。拟合得到齿轮轴线，作为螺旋线偏差评定的基准。针对测量点为离散坐标点，无法通过测量得到分度圆对应的实际螺旋线测量点的精确坐标值的问题，采用测量点直线插值法，提出了一种基圆坐标转换的螺旋线偏差评定方法，通过坐标转换、降维，得到螺旋线偏差的计算模型。验证实验结果表明，用本方案测量标准齿轮，测量结果在精度允许范围内。在螺旋线偏差比对实验中，齿轮测量中心测得两个齿轮的螺旋线偏差与本方案测量结果之间差值分别小于2μm和6μm。本成果可提供一种特大齿轮在线检测方法，并有望解决水电站、航母等领域特大齿轮生产过程中的检定问题，提高特大齿轮制造的精度和合格率。