Research On Jacquard Control Technology For Digital Tufting Carpet Machine

Recently our country’s tufting carpet consumption keeps growing rapidly, as the living standards improve. But most carpets in the market are of inferior quality. Those inferior carpets cannot satisfy people’s needs, and will crimp the industry’s growth. Therefore, it’s very important to improve tufting carpet and carpet machine, and the research on new type tufting carpet machine and related key technologies is very meaningful for our domestic carpet industry. How to control the feeding of yarn efficiently and precisely? How to make the jacquard system more suitable for industrial production? These problems must be solved as they are the prerequisites for making high quality multi-loop embossed tufting carpets. The research aims to solve these questions.Based on existed digital tufting machine and other related technologies, two main parts of jacquard system—pattern preparation system and jacquard control system were designed and optimized, furthermore, the other system, online function monitor system was completed as well. Besides, the field tests had been finished. The details about the research are listed as follows.(1) Overall designBased on the working principal of jacquard system of tufting carpet machine and tufting process, the overall design of jacquard system was put forward. And a CAN-based stepping-motor-driven electronic-roller group controlling jacquard system was built.(2) Pattern preparation systemThe pattern preparation system is mainly used for pattern image processing, to switch a computer image into a technical pattern one. The key technology involves here is improved color quantization algorithm, which aims to reduce the color types to a required number automatically and, in the meanwhile, not to jeopardized the original image style to the utmost. In this algorithm, weighted chromatic aberration is adopted as the color-processing standard to assemble and split color groups dynamically.(3) Jacquard controlling technologySome new technologies were brought into to improve jacquard controlling process precision on existing machine. Technology one is dynamic priority algorithm, which aims to improve the real-time quality of CAN network. By redesigning the CAN’s communication protocols, a dynamic priority-decide method can be achieved. Technology two is optimized stepping-motor controlling method, which is used to alleviate the negative influence that brought by motor’s dynamic characteristics. Furthermore, both of these improved technologies were tested in lab and field.(4) Online function monitor systemA CAN-based online monitor system was designed according to the function requirements of jacquard system. This system can not only monitor the whole system’s working situation in time, but also diagnose and deal with faults automatically.Main conclusions from this research can be summarized in three propositions.(1) Modified color quantization algorithmModified color quantization algorithm does optimize image-processing results. The new image after the quantification doesn’t left out low-frequency key colors, and also keeps the old one’s style.(2) Dynamic priority-deciding algorithmDynamic priority-deciding algorithm does decrease the network communication delay. When the technology is applied to digital tufting carpet machine, the pile height errors are reduced markedly.(3) Optimized stepping-motor controlling methodOptimized stepping-motor controlling method did reduce the negative impact of stepping-motor’s dynamic characteristics. When the technology is applied to digital tufting carpet machine, the pile height errors level down, as the response time and rotate speed oscillation decrease.