谐波齿轮传动中杯形柔轮的有限元计算与分析

FINITE ELEMENT CALCULATION AND ANALYSIS ON THE COLUMN-SHAPED FLEX SPLINE OF HARMONIC DRIVE

基于简化的柱形壳体理论的柔轮应力计算是一定程度上的近似,实际工况中柔轮的齿圈开裂问题难以克服。以谐波齿轮传动中的杯形柔轮为例,建立柔轮啮合的仿真实体模型,在啮合齿对接触边界的节点之间建立面一面接触单元,用三维弹性接触问题有限元法较全面地计算和分析了承载柔轮齿圈和筒体的应力大小及分布规律、轮齿变形及影响机理。找出了柔轮开裂在设计阶段的主要原因,预测了危险断面的位置。根据柔轮理论、利用有限元计算结果重新计算并修正了轮齿影响系数,重新校核了柔轮强度。与理论计算结果和破坏实例对比得到了更接近实际的结果,为研究柔轮问题提供了一种更精细、高效的方法。

The calculation of the flexspline stress, which is based on the simplified theory of the column-shaped shell, is to some degree not very accurate. So the fracture of the ring gear in column-shaped flexspline in reality has always remained a problem hard to solve. The column-shaped flexspline at harmonic drive is taken as an example here, and a model imitation of the engaged flexspline is set up. A surface-to-surface contact element is set up between the nodes on the contact surface of the engaged gears. Applying the finite element calculation of 3-D elastic contact problems, a thorough calculative and analysis is done in terms of the stress and its distribution of the bearing flexspline ring gear and the column, of the deformation of the gears tooth and the effect. The main reason of the flexspline fracture in the design phase has been found out, and the position possible dangerous section is predicted. According to the flexspline theory, a calculation with above result is conducted again the effect coefficient of the gear tooth is revised, and the flexspoine strength is double checked. In general compared the theoretical calculation to the actual fracture, a more close-to- the-reality result is reached, in addition, a more accurate, efficient method for solving flexspline problem is offered.