高速电脑绣花机结构优化设计

Structural optimization design of high-speed computerized embroidery machine

针对国产链目毛巾绣电脑绣花机主轴电动机转速超过1 000 r/min时容易出现振动噪声过大、断线率增加,甚至机械结构卡死等现象,对现有国产机器的机械结构进行分析,对其针杆的运动学特性进行研究,分析导致故障产生的原因。根据这些原因对绣花机的机械结构进行优化设计,并通过优化凸轮机构轮廓曲线提高了针杆机构运动的柔顺性。在ADAMS环境中对机构优化前后的动力学特性进行仿真,仿真结果表明,优化后针杆机构最大受力减小约50%。最后对绣花机高速刺绣时的振动性能进行测试,实验结果表明,优化后绣花机振动幅度远小于允许范围,机器性能得到了明显改善。

Large vibration noise, high thread-broken rate, even failure of mechanical drive system will arise when the speed of main spindle motor of chain stitch chenille embroidery machine made in China overpasses 1 000 r/min. In order to overcome these problems, mechanical analysis of the existing embroidery machine was provided, and kinematics characteristics of the needle-bar-structure was analyzed. The reasons which cause the failure was analyzed. An optimal mechanical design was provided to solve these problems. The movement flexibility of needle-bar-structure was improved by optimizing the cam system. Force analysis of the connecting rod of the needle-bar-structure were compared before and after optimization in ADAMS simulations. Simulation result shows that the maximum force reduces 50% after optimization. In the end, a vibration testing experiment was carried out. Results show that the vibration is far less than the allowable value after optimization, and the performance is improved obviously.