异形非对称柔性铰链力学特性的研究

Study on the Mechanical Characteristic of Special-shaped Asymmetric Flexure Hinge

基于大柔度混合柔性铰链设计理念,提出了一种非对称式直圆摆线混合柔性铰链,并对其力学特性进行了研究。基于悬臂梁弯曲理论和微元法下的胡克定律,通过选取合适的积分变量与中间变量,得到较为简洁的转动柔度和拉伸柔度的计算公式,并给出了最大应力的计算公式;讨论了转动柔度和最大应力随参数的变化趋势,比较了结构参数对转动柔度和最大应力影响的显著程度。结果表明,转动柔度、拉伸柔度和最大应力解析式的最大误差分别在7%、5%和5%以内;转动柔度与弹性模量、宽度和最小厚度成反比,与直圆半径和拱高参数成正比,且对最小厚度的变化最为敏感,宽度次之,拱高参数和直圆半径最弱;最大应力与宽度、最小厚度和直圆半径成反比,且对最小厚度的变化最为敏感,宽度次之,直圆半径最弱。

Based on the design concept of hybrid flexure hinge with large flexibility,an asymmetric hybrid flexure hinge with straight circle cycloid is proposed,and its mechanical characteristics are studied.Based on the bending theory of cantilever beam and Hooke’s law under the micro element method,by selecting the appropriate integral variable and intermediate variable,the relatively simple calculation formula of rotational flexibility and tensile flexibility is obtained,and the general calculation formula of the maximum stress is given.The variation trend of rotational flexibility and maximum stress with parameters is discussed.The influence degree of structural parameters on rotational flexibility and maximum stress is compared.The results show that the maximum errors of the analytical expressions of rotational flexibility,tensile flexibility and maximum stress are within 5%,1%and 5%,respectively.The rotational flexibility is inversely proportional to the elastic modulus,width and minimum thickness,and is directly proportional to the straight circle radius and arch height parameters,and is most sensitive to the change of the minimum thickness,followed by the width,and the arch height and straight circle radius are the weakest.The maximum stress is inversely proportional to the width,minimum thickness and the radius of the straight circle,and it is most sensitive to the change of the minimum thickness,followed by the width,and the radius of the straight circle is the weakest.