注塑机合模装置连杆过渡结构设计分析

针对注塑机双曲肘内翻式合模装置十字头连杆过渡结构应力集中现象和出现断裂问题,以双曲肘内翻式合模装置为研究对象进行分析,研究并提出了一种采用曲面过渡的设计方法。对合模装置十字头连杆进行了动力学、静力学仿真分析表明过渡处应力集中明显,超出安全系数1.5的许用应力值,是导致十字头连杆断裂的原因。根据圆过渡设计方法中的半径和出现最大应力值位置的关系,提出了一种过渡曲线方程,以该曲线构造过渡曲面,降低过渡结构最大应力值。通过与圆过渡设计方法和楔形面过渡设计方法对比,研究结果表明,该方法对降低过渡处最大应力值具有有效性。

Transitional structure design and analysis on cross head link of clamping mechanism of injection molding machine

Aiming at the stress concentration phenomenon and the fracture problem in the practical work in the transitional structure of crosshead link,the varus type of double-toggle clamping mechanism was regarded to analyze and a design method with surface in the transitional structure was proposed.The dynamics simulation and the static finite element analysis were carried out on the crosshead link,the results showed that the stress concentration was obvious,the maximal stress exceeded the safety factor-1.5 of allowable stress and it was the cause of the crosshead link fracture.Based on the relationship between radius and position of maximal stress in circle surface design method,a transitional curve equation was presented to construct the surface to reduce the maximum stress in the transitional structure.The comparison was carried on with the circle surface design method and wedge surface design method,the results indicate that the method verify the effectiveness of reducing the maximal stress of proposed design.