基于非均匀有理B样条的空间凸轮设计  

Design of Spatial Cam Based on Non-uniform Rational B-splines

作　　者：孙树峰[1] 周以齐[2] 

机构地区：[1]温州大学机电工程学院,温州325035 [2]山东大学机械工程学院,济南250061

出　　处：《机械工程学报》2009年第8期125-129,共5页Journal of Mechanical Engineering

基　　金：国家自然科学基金(50175063);温州市科技计划(G20080028)资助项目

摘　　要：针对高速传动空间凸轮在使用过程中存在的平稳性降低、噪声增大、磨损加剧等问题,提出一种新的基于非均匀有理B样条(Non-uniform rational B-splines,NURBS)的空间凸轮设计与加工技术,利用NURBS曲线拟合修正正弦曲线构造从动件运动轨迹曲线,利用单参数曲面族包络原理设计空间凸轮沟槽廓面,借助数控机床的NURBS插补功能实现空间凸轮的高精度光顺加工。实践证明,NURBS方法比常用的修正正弦方法设计得到的从动件运动规律曲线(包括位移、速度和加速度曲线)光顺性更好,NURBS插补方法比常用的直线或圆弧插补方法加工得到的空间凸轮噪声更低。因此,基于NURBS的空间凸轮设计方法简单易行,用该方法制造的空间凸轮在高速传动时具有传动平稳、噪声低、使用寿命长等优点。On the problem of lower stability, bigger noise, quicker wear of spatial cam during high speed transmission, a new technique of design and manufacturing of spatial cam based on non-uniform rational B-splines（NURBS） is proposed. To construct geometric locus of follower, NURBS is used to fit modified-sine curve. The theory of envelopes of one-parameter family of surfaces is used to determine the surface geometry of cylindrical cam profile. The spatial cam is machined on CNC machine with NURBS interpolation to obtain high precision and smoothness. It is verified that the motion curves （including curves of displacement, velocity and acceleration） of follower obtained by using NURBS is smoother than that obtained by widely used modified-sine method. The noise of spatial cam machined by NURBS interpolation method is lower than that of usually used linear or arc interpolation method. Therefore, the design method based on NURBS is simple and practicable. The spatial cam manufactured by using this method has the advantages of stable transmission, low noise, and long lifespan during high speed transmission.

关 键 词：空间凸轮 非均匀有理 B样条 修正正弦曲线 插补 

分 类 号：TH132.47[机械工程—机械制造及自动化]