Development Of Digital Sample Spinning Frame Control System

A new digital sample spinning frame was developed in this subject, who has double sided and double spinning system, 12 spindles each side. The left side is installed wool spinning draft mechanism suitable for spinning 65～120 mm wool type fiber, but the right side is installed cotton spinning draft mechanism suitable for spinning 22～65 mm cotton type fiber. Moreover, both sides can spin slub yarn without mechanical adjustment. The core of control system is programmable logic controller (PLC), electronic draft and electronic shaping system has been realized by controlling the servomotors of front roller, middle roller, back roller and ring rail through PLC high-speed pulse output, and stepless spindle speed regulation has been adopted by inventor controlled through RS485 communication mode. The spinning process parameter online design and real-time monitoring can be realized on touch screen, in addition, these functions also can be done in host computer.This thesis particularly explains the digital sample spinning frame control system, and the main contents are as follows:Chapter 1, Expatiated China's overall textile machine industry situation, analyzed the development status of spinning frame home and abroad and summarized its technology characteristics. Pointed out the disadvantages of conventional sample spinning frame, and then put forward the research content and significance of this subject.Chapter 2, Based on digesting and absorbing the conventional spinning frame mechanical structure and working principle, described the digital sample spinning frame spindle, draft transmission mechanism and the rising and falling mechanism of ring tail, then established mathematic model of each transmission unit and slub yarn control method.Chapter 3, the overall design scheme of control system was given and such problems as the control system structure and principle, circuit schematic diagram, draft, spinning winding shaping and spinning tension were detaily explained.Chapter 4, the communication protocol and the definition of communication data packet format were designed, including the communication between host computer and master controller, as well as the communication between master controller and other control objects.Chapter 5, the software design of the control system was introduced, containing electronic shaping system, closed-loop spindle speed control, spindle speed curve setting, precise length measure system, slub yarn control scheme, human machine interface and host computer program design.Chapter 6, a lot of spinning tests were done by using digital sample spinning frame and yarn quality index was measured. In the same process, the comparable spinning test between digital sample spinning frame and existing mechanical sample spinning frame, and the test results were analyzed.Chapter 7, summarized this paper and given sample spinning frame characteristics and performance index, and pointed out the problems such as sample spinning system and the application of spinning frame control technology etc that need future research.