The Design Of Electronic Control System For Jet Looms

In 1980s, the jet loom made rapid progress in production. But its control technique always prevented it from being popular and widely used, among which the low precision, short sustaining working hours and the awful stability were the key problems.Recently, 32-bit micro processors have taken place of the traditional 8-bit/16bit micro processors as the main platform for high speed applications, which enables the transplantation of real time operating system. Under such circumstances, this paper gives a design plan based on 32-bit mcu plus RTOS.32-bit ARM core platform is more efficient and powerful compared with 8-bit/16-bit platforms. It can get rid of the root cause of the low-precision problem since multiple processors work in cooperation is powerful enough to handle all the work of controlling, detecting, and manipulating of jet looms. Meanwhile, the use of real time operating system promises high stability and long sustaining working hours. It also makes the software system easy to update. Only a little part of the transplantation code needs to be modified to update to an advanced micro processor.The functions of the system are as follows:1) Electronic let-off system. To make real time detection of the yarn tension with high precision, and give out the motor speed by computing various parameters such as the main spindle speed, abb tension, yarn shrink rate and so on.2) Electronic abb storage instrument to stabilize abb tension. Abbs from the main nozzles are relayed by the assistant nozzles and the cut nozzles to reduce the number of fault points.3) Electronic take-up system. Use double photoelectric abb detection instrument to detect missed abbs, loose abbs and broken abbs, so that fault points can be minimized.4) Control stop and start at designated degree along with one-shuttle and back-roll function to decrease fault points.5) Use instrument to prevent start mark and decrease fault points.6) Make real time detection of every part of the jet loom and response to system fault by stoping the system or else automatically.7) Use large-screen LCD and multi-function keyboard. The system is able to show real time information of working status and parameters. Also give keyboard interface to change parameters and working methods.