The Research On The Overprint Detection System In Rotary Screen Wallpaper Machine

The wallpaper is more and more popular because of its beauty and environmental friendly features. In the wallpaper production process, each unit needs to nest the colors,which combine into a beautiful wallpaper pattern. We can use gravure, flexo, rotary screen Roller to product wallpaper.In our topic,the rotary screen printing is the emphasis. In the rotary screen wallpaper electrical control systems, automatic register control system is not only one of the key technologies,but also the important factor to ensure printing quality and printing speed. This topic belongs to overprint detection system,which is the most important part of the automatic register control system. Only in the event of chromatic deviation, with rapid and accurate detection of the color signal and dealing with error data timely,can we ensure the quality of printing, and automatic registration system stability.In zhe topic,we has studied production process and trapping detection principles. On the DGE’s basis of printing machinery automation technology, combining with the actual production characteristics and problems that is encountered in the rotary printing,we developed a set of error detection and processing system independently.The system uses the extension board to acquire and process data information and upload the data to master by the CAN bus. The hardware platform of extension board embedded consists of FPGA and DSP. In order to enhance the accuracy of color signal acquisition,the system uses a technology that reference voltage can vary automatically and the wave door is setted. Through the differential transmission, the photoelectric encoder signal, proximity switch zero signal is proceesed by FPGA. This paper describes the overall program of the overprint detection system and focus on descripting the use and detection methods of the main signal. In terms of hardware design, the selection, functions and other peripheral circuits of the components are described in detail.Under the Quartus II 9.0 software development platform,we design and debug the FPGA program module. The DSP software design and debugging is performed in CCS3.3.After the hardware and software design has been completed, we carry out the debugging and verification work of the entire system in the laboratory.The experiments prove that the whole overprint detection system is running well,It can be applied to the DGE rotary screen printing wallpaper production line with meeting the needs of actual production.The System can effectively improve the accuracy of the detection and control in the rotary screen wallpaper printing machinery.