织网机下钩机构凸轮轮廓曲线优化

Cam Outline Curve Optimization for Upper Hook Mechanism of Netting Machine

为满足织网机织网成型的需要,依据下钩双凸轮连杆机构的工作原理,设计完成了下钩机构的工作循环图,绘制了前后和上下凸轮从动件运动规律图;采用解析法推导出凸轮的理论和实际轮廓曲线方程,再根据从动件运动规律选择原则,确定选择摆线修正等速运动规律,避免等速运动规律在开始和终点处速度发生突变、凸轮机构受到刚性冲击和柔性冲击,使织网机下钩机构的输出运动规律具有良好的运动学性能;最后,采用MATLAB对凸轮廓线进行辅助设计,得到下钩机构前后和上下凸轮的理论和实际轮廓曲线。

To meet the needs of making knot for fishing net,according to the working principle of the double cam link mechanism,we design the working cycle of the hook mechanism and draw the motion cycle diagram of the front and rear cam follower.The analytic method is used to derive the theoretical and the actual contour curve equation of cam.According to the principle of motion of follower motion,we select the law of the constant velocity motion,avoiding sudden change in the velocity in the beginning and the end of the constant velocity movement,which makes the cam mechanism subject to rigid impact and flexible impact,and makes the output motion mechanism of the machine have good performance.Finally,the cam profile is designed by using MATLAB,and the theoretical and the actual contour curves of the lower hook mechanism ＇s cams are obtained.