针织纬编氨纶输送控制技术

为解决低模量、高弹性、高回复率特性的氨纶在编织生产过程中送纱量难以调节控制的问题,采用快速响应的积极式送纱器作为动态输送纱线的驱动器,以可调占空比的脉冲宽度调制脉冲实现模拟量控制信号输出,以高性能高级精简指令集机制处理器为控制核心,采用位置和速度双闭环方式设计氨纶送纱实时控制器,实现氨纶的输送量动态调节和恒张力输送。研究了氨纶输送的工艺要求,阐述了送纱控制器的硬件设计和软件开发,提出了送纱控制器与整机控制系统的同步方案。实验结果表明,采用该控制方案的纬编织物成圈均匀整齐,无横条暗纹,弹性良好,验证了氨纶送纱量控制方案的可行性。

Control technology for spandex yarn delivery in weft knitting

The amount of spandex yarn delivery is difficult to adjust and control in weft knitting process because of its low modulus,high elasticity and high recovery rate.The fast response positive yarn feeder was used as the drive for yarn delivery.Analog control signal output was achieved using the pulse width modulation(PWM)with adjustable duty cycle.The high performance advanced RISC machines(ARM)processor was used as the control core,and the position and speed double closed loop mode was adopted.The real-time controller of the spandex yarn was designed to achieve the dynamic adjustment and constant tension delivery.The process requirements of spandex delivery were studied,and hardware design and software development of the yarn feeding controller were addressed.The synchronization scheme between the yarn dilivery controller and the whole machine control system was made.The experimental results show that the weft knitted fabrics produced with the new control scheme is even and tidy in circle,without dark stripes and with good elasticity,which verifies the feasibility of the spandex delivery control scheme.