塑料非圆齿轮的齿廓设计与运动分析

Tooth Profile Design and Kinematic Analysis of Plastic Non-circular Gears

非圆齿轮是一种能够实现变速运动的特殊齿轮,利用塑料代替金属材料制造非圆齿轮,在小模数规格的传动领域具有较大潜力。针对塑料非圆齿轮的齿廓设计难点,提出一种基于运动仿真技术的模拟范成法创建轮齿。根据塑料齿轮基本齿条齿廓的结构参数设计齿条型刀具,并编制程序绘制非圆齿轮节曲线,以节曲线为基准生成齿坯,通过齿条型刀具与齿坯的相对运动得到了非圆齿轮的实体模型。将非圆齿轮进行虚拟装配后进行运动试验,得到了非圆齿轮副的运动特性曲线,试验结果与理论分析保持了较好的一致性,从而验证了齿廓的正确性。该方法不仅精确直观,而且易于实现系列化、变异化设计,能够促进塑料非圆齿轮的应用与推广。

Non-circular gear was a special gear that could realize variable movement.It was manufactured by plastics in place of metal materials,that had great potential in the transmission field of small module series.Aiming at tooth profile design difficulties of plastic non-circular gears,a method of creating gear teeth by generation based on dynamic simulation technology was proposed.According to the structural parameters of plastic gearing toothform basic rack tooth profile,the rack tool was designed,and the program was compiled to draw the pitch curve of non-circular gears.The gear blank was generated based on the pitch curves,and the non-circular gear solid model was obtained through the relative motion between rack tool and gear blank.After the virtual assembly and exercise test,the motion characteristic curve of non-circular gear pair was obtained.The simulation results are in good agreement with the theoretical analysis,which verifies the correctness of the tooth profile.It shows that the proposed method is not only accurate and intuitive,but also convenient for serialization and variation design,and can promote the application and popularization of plastic non-circular gear.