4种柔性铰链的温度效应比较分析  

COMPARATIVE ANALYSIS OF TEMPERATURE EFFECTS ON FOUR KINDS OF FLEXURE HINGES

作　　者：胡俊峰[1] 郝亚洲[1] 徐贵阳[1] 

机构地区：[1]江西理工大学机电工程学院,赣州341000

出　　处：《机械强度》2016年第1期144-150,共7页Journal of Mechanical Strength

基　　金：国家自然科学基金资助项目(51265016);江西省自然科学基金资助项目(20122BAB216029)资助~~

摘　　要：为了减小温度效应对柔顺机构的影响,比较分析直梁、直圆、椭圆和抛物线型4种典型柔性铰链的温度效应,以便合理选取柔性铰链设计柔顺机构。将柔性铰链划分为2个变截面梁单元,计入温度变化产生的初应变,采用最小势能原理推导出4种柔性铰链的热载荷向量和刚度矩阵,采用拉格郎日方程得出其质量矩阵,得出铰链的力学模型。基于柔性铰链的有限元模型,并以柔顺四杆机构为算例,分别对基于4种柔性铰链的柔顺机构的精度、热应力和热振动进行比较分析,分析结果表明:直圆型铰链的热误差最大,抛物线型次之,椭圆型和直梁型最小;所受热应力由大到小的顺序为直圆、椭圆、抛物线和直梁型铰链;直梁型柔性铰链的热振动谐振频率最小,直圆型和椭圆型次之,抛物线型最大,说明直梁型柔性铰链更容易受动态温度变化影响,但抛物线型在谐振频率处的幅值最大,抛物线型铰链热振动更大。In order to reduce the temperature effects on compliant mechanisms, the comparative analysis of temperature effects on four kinds of typical flexure hinge with straight-beam, circular, elliptic and parabolic section is carried out, so that we can choose reasonablely the flexure hinge used to design compliant mechanisms. The flexure hinge is diviede into two variable cross-section beam elements, and the initial strain caused by temperature change is accounted into. The principle of minimum potential energy is applied to derive the thermal load vector and stiffness matrix of four kinds flexure hinge, and the mass matrix is obstained by employing Lagrange equation. And the mechanical model of the flexure hinges is obtained. The comparative analysis of the precision, thermal stress and thermal vibration of the compliant four-link mechanism is carried out based on the finite element model of the flexure hinge. The analysis results showed that the thermal errors of circular hinge is largest, and parabolic one, elliptic and straight-beam is smallest; The sequence of thermal stress from large to small is circular, elliptic, parabolic and straight-beam flexure hinge; The thermal vibration resonant frequency of the straight-beam hinge is minimum, the circular and elliptic one is second, parabolic is maximum, and it illustrated that the straight-beam hinge is more sussceptible to temperature changes. But the amplitude of the parabolic hinge at the resonant frequeey is maximum, and the thermal vibration is more larger.

关 键 词：柔性铰链 有限元法 温度效应 比较分析 

分 类 号：TH112[机械工程—机械设计及理论]