【作者】 王萌；

【导师】 刘铁根； 张国顺；

【作者基本信息】 天津大学 ， 光学工程， 2007， 硕士

【摘要】 传统模切技术通常采用木制镶刀板,通过机械冲压将纸质包装盒制作出来,工艺复杂、耗时很长,而且完成之后难于修改,在数量小、外形多变的情况下,就显得尤为复杂。针对这种情况,我们设计了一种涉及光学、机械学、电子学、计算机控制等多种学科的数控激光模切系统,使用计算机绘制模切图纸,然后控制激光束直接聚焦到被加工板料表面,通过激光束的移动将包装盒切割下来。同时通过控制激光束的移动速度和功率强弱,可以在包装盒表面进行划痕、打孔、打标、加密等复杂动作。本课题在激光加工过程的物理学基础上,对用于纸质包装盒数控激光模切系统进行了研究。论文首先从传统模切技术入手,介绍当前技术的现状和不足,然后引入激光加工概念,将常用的激光加工手段进行分析。通过比较选出最适合模切的激光器和外光路结构,并对比传统技术指出激光模切的优势。然后详细研究了激光模切的原理、激光与物质相互作用的过程、振镜系统的原理、飞行光路的原理、激光能量的数字控制以及如何通过PCI总线结合DSP控制激光束的移动和激光强弱的变化。并针对不同尺寸的包装盒制定出振镜和飞行光路两种不同的加工系统。振镜激光加工系统在原有基础上,将模拟控制方式升级为数字控制方式,提高了控制精度,大大降低了传输中的信号干扰;增加了气体流动装置,对光学镜头起到了很好的保护;更新了软件控制系统,使之使用起来更加方便快捷。飞行光路系统则是一种全新的激光模切方式,针对大尺寸的包装盒展开图进行加工,加工范围是振镜系统的几十倍,采用伺服控制系统带动二维精密激光头运动,时时检测实际位置和设定位置之间是否存在差异并修正。论文还提出了一种新的路径优化算法,通过对构建的数学模型进行分析,找到该数学问题的最优解,并编写软件对模切图样进行分析,将绘制时的独立线段自动连接成整体后,找出最短加工行程,这样不仅可以缩短加工时间,而且还可以减少切口,提高加工质量。最后通过实验数据验证了激光模切系统的可行性、稳定性和精度,达到设计要求,找到了最适合加工的一些参数。并提出了现存的不足之处,以及需要进一步解决的技术问题。更多还原

【Abstract】 Traditional mechanical die-cutting technology usually uses wood die to produce paper packing by mechanical pressing. It costs time and is also complicated. A finished die is very difficult to be modified,particularly to produce a small quantity or different shapes. To solve this problem, we designed a digital controlled laser processing system which involves optics, mechanics, electronics and computer science. The system process the surface of the material by laser based on the design of the packing by control of computer and die-cut packing by moving the beams of laser. Also, it can crease, perforate, mark and encrypt on the pack surface by controlling the laser power and speed.The purpose of this paper is to research the processing of digital controlled laser on paper packing system base on the analysis of the laser die-cutting physics theory. The paper begins from traditional die-cutting technology, introduces the status quo of current die-cutting technology and its shortage,then followed with the concept of laser process, compares common laser processing methods, chooses the most compatible laser and optical circuit. After studying the principle of laser die-cutting technology, the process of laser and substance working on each other,the theory of high speed galvanometer scanning system, the fly optical circuit principle, the laser power digital controlled circuit and how to control the laser moving and power by PCI bus and DSP are expounded. We designed the galvanometer scanning system and fly optical circuit for different packing size.Galvanometer scanning system is improved from analog control to digital control, makes higher precision, reduces signal disturbance during transportation. And we increases air flow equipment which gives optical lens good protection. Through updating the software control system, the galvanometer scanning system becomes faster and more convenient. Fly optical circuit system is a new way of laser die-cutting. It processes packing size as tens time of galvanometer scanning system. When the server control system drives two dimension precision laser head, it checks the difference between the factual position and set position and corrects.The paper also raises the point of new optimized path arithmetic. That is to find out the best resolution through the analysis of constructed mathematical model, and to design software to analyze die-cutting paper. After connecting the individual line segments into a combination, finding out the shortest processing distance, we can shorten the time cost of process and reduce kerfs, improve quality.At last we validate the system stability and precision by experiment. The result is accord with the design. Some suitable processing parameters, something that can be improved, some technology problems to be solved are all mentioned here.更多还原