变焦距镜头凸轮结构优化设计  

Optimal design of cam structure of zoom lens

作　　者：王平[1] 张葆[1] 程志峰[1,2] 赵阳[2] 

机构地区：[1]中国科学院长春光学精密机械与物理研究所,吉林长春130033 [2]中国科学院研究生院,北京100039

出　　处：《光学精密工程》2010年第4期893-898,共6页Optics and Precision Engineering

基　　金：武器装备预研基金资助项目(No.51460040104ZK1001); 国防预研基金资助项目(No.1040603)

摘　　要：变焦距镜头普遍采用机械补偿法来改变焦距,变焦凸轮是其实现连续变焦的关键。为了减小变焦距镜头的质量和体积,本文研究了用机械补偿方式改变变焦距镜头焦距的原理,采用NX/Nastran软件对变焦凸轮结构进行了仿真分析,并针对分析结果对变焦凸轮结构进行了优化设计。优化结果使变焦凸轮质量减小了88g,壁厚减小了1.5mm,外径尺寸减小了3mm。对优化后的变焦凸轮进行了模态分析和热分析。模态分析显示,凸轮主体一阶频率为50.3Hz;热分析显示,凸轮在90℃温差作用下变形大小为0.006mm。最后通过对光学传递函数的检测以及振动和高低温试验验证了仿真分析的正确性,表明对变焦凸轮的优化设计是成功的。The mechanical compensation method is generally used to change the focal length of a zoom lens,in which the zoom cam is a key component to achieve the continuous zoom of the zoom lens.In order to improve the quality of the zoom lens and reduce the size of component,the priciple of changing focal length of zoom lens by the mechanical compensation method is researched and the structure of zoom cam is analyzed with the software of NX/Nastran.Then,the optimization design of the zoom cam structure is achieved based on the analysis results.The final optimization results show that the mass of zoom cam has tightened by 88 g,the wall thickness reduced by 1.5mm,and the size of outside diameter decreased by 3 mm.The modal analysis and thermal analysis are carried out on the optimized zoom cam,it indicates that the cam’s first-order natural frequency is 50.3 Hz by modal analysis and the deformation size of cam in the temperature difference of 90 ℃ is 0.006 mm by thermal analysis.Finally,through the lens transfer function test,vibration test and high and low temperature tests,the correctness of finite element analysis and optimization analysis are proved,which indicates that the optimized design of zoom cam is successful.

关 键 词：变焦距镜头 凸轮 结构设计 

分 类 号：TH703[机械工程—仪器科学与技术]