On April 10, 2018, the 8th National Knitting Science and Technology Conference, hosted by the China Knitting Industry Association, was held in Haining, Zhejiang. Mr. Gu Ren, chairman of Changzhou Hongda Technology (Group), was invited to attend the conference and gave a report titled "Industrial Application of HawkVision Intelligent Image Fabric Pattern Correction Technology." In the report, Mr. Gu introduced Changzhou Hongda's technological research and product applications in intelligent knitting in recent years. He particularly provided detailed solutions and product recommendations for the problems faced by enterprises in Haining, the location of the conference, regarding the urgently needed pattern correction technology and products in the production of wall coverings and curtains. Finally, he shared successful application cases from local enterprises, which elicited enthusiastic responses and keen interest from the attending enterprises!

HawkVision Intelligent Image Fabric Pattern and Weft Correction Machine, assisting knitting enterprises in product upgrades

Due to the relatively loose weave, high permeability, and softness of knitted fabrics, pattern deformation often occurs during processing and finishing. For example, printed knitted fabrics during washing and jacquard knitted fabrics during finishing are prone to pattern deformation, especially geometric patterns, which seriously affects the first-pass yield and product quality, leading to frequent quality complaints and disputes.

The Hawk Vision Intelligent Image Fabric Pattern and Weft Correction Machine, leveraging the strong European technical background of the "Hawk Vision" brand and the profound R&D strength of Changzhou Hongda, has reformed and innovated the "full-width scanning pattern and weft correction technology." With full-width scanning of more than 8000 monitoring points, it completely solves the problems of pattern deformation, weft skew, and weft bending in knitted fabrics that cannot be corrected or identified by photoelectric weft correction, surpassing the value of photoelectric weft correction and ordinary image weft correction. This technology won the first prize of the China Textile Industry Federation Science and Technology Progress Award in 2017.

The HawkVision Intelligent Image Fabric Pattern and Weft Correction Machine has wide variety adaptability. In addition to being suitable for all varieties applicable to photoelectric weft correction, it is also suitable for many varieties that cannot be normally identified and corrected by photoelectric weft correction, such as jacquard knitted fabrics, printed knitted fabrics, heavy knitted fabrics, brushed knitted fabrics, and knitted fabrics with complex weaves, greatly improving the post-finishing quality of knitted fabrics.

Online Detection of Knitted Fabric Printing Clogging

During the knitting printing process, periodic white spots (missing prints) and color spots (contamination) often form on the fabric due to factors such as the printing screen head or dye and screen head contamination. Because the printing machine cannot be stopped frequently, once some defects occur, they will appear periodically in the same position, resulting in continuous defective products. Compared with some random black and ink spots, continuous defective products during the printing process will have a greater impact on the quality of the entire batch of fabrics.

This detection system is installed on the printing machine to perform 100% quality monitoring of the fabric. When fabric defects are detected, it can promptly alert workers to adjust the printing machine, thereby improving product quality. This system uses machine vision image processing technology to automatically detect and alarm for screen clogging during printing, continuously and online monitoring printing quality in real time. The entire process is continuous real-time detection with minimal manual intervention. It can greatly reduce the skill requirements and labor intensity of operators, improve product yield, and is an essential product for high-end knitted printed fabrics.

Automatic Overfeeding Control System for Stentering Machine

Due to the knitting method and material of knitted fabrics, they are easily stretched and narrowed during processing and finishing. Therefore, in order to ensure the stability of the weight and size of the knitted fabric, the density during the fabric setting process must be automatically controlled. The stentering machine overfeeding control system uses intelligent image technology to monitor the weft density of the fabric on the fabric feeding side during the setting process. When the weft density of the fabric cannot reach the set value, the overfeeding adjustment system adjusts the weft density to the ideal state in real time to ensure consistent weft density of the outgoing fabric, achieve the standard unit area weight of the knitted fabric, improve the first-pass yield, and provide a guarantee for high-quality textiles.

The "green production and intelligent manufacturing" promoted at this conference is both a trend and timely. Changzhou Hongda, with its nearly 30 years of focus on the research and development of digital technology for textile printing and dyeing, will continue to provide technological support for intelligent equipment in the textile printing and dyeing industry, fully assisting the knitting industry in promoting "green production and intelligent manufacturing," and leading the automation, intelligence, and digital networking development of the textile printing and dyeing industry.