被动球面铰链是构成机构的基本单元之一,但是,较小的工作空间制约了其在机械结构设计中的应用。以普通被动球面铰链为原型,在对其结构及工作空间进行分析的基础上,采用运动与约束单项分解、交叉匹配的方法,提出并设计完成了具有较大工作空间的双耳支架固定型被动球面铰链和球/窝换位型被动球面铰链;基于仿生设计理论,对照人体肱骨结构,提出偏置输出的设计新思想,进而,设计完成具有大工作空间的偏置输出的横向剖分球窝型被动球面铰链和偏置输出的球/窝换位型被动球面铰链;建立两空间映射的函数方程。分析发现,随着铰链输出杆偏置角的增大,铰链的工作空间随之增大,并且形状发生相应变化。所提出的新型铰链,解决了被动球面铰链因工作空间小而在工程应用中受到限制的问题,对新型被动球面铰链的研制具有理论指导意义和工程实践价值。
The passive spherical hinge is one of the basic units of mechanisms, but the small workspace limits its applications in the design of general mechanical structure. The traditional passive spherical hinge was chosen herein as the prototype and its structure, workspace were analyzed. And then, the binaural bracket fixed type passive spherical hinge and the ball and socket interchanged type passive spherical hinge were proposed by the method of decomposing motion and constraint separately and staggered matching, and the workspaces of the two passive spherical hinges were large. The design idea of offset output was proposed according to the theory of bionic design and the structure of human humerus. Based on this design idea, the ball socket laterally split type passive spherical hinge with offset output and the ball and socket interchanged type passive spherical hinge with offset output were proposed, and the workspaces of the two passive spherical hinges were super large. It is shown that the workspaces increase and their appearance changes correspondingly in pace with the increase of the offset angle of the output rod. The proposed passive spherical hinge expands its application range in the field of the mechanical structure and it has theoretical significance for the development of novel passive spherical hinge.