【作者】 廖忠浩；

【导师】 蔡善乐；

【作者基本信息】 兰州理工大学 ， 机械设计及理论， 2008， 硕士

【摘要】 现实中广泛存在着需按工件原有螺纹螺旋线基础上再进行加工工件的数控加工,如石油钻杆接头螺纹的修复加工,丝杠精加工等,由于其需要在原有螺纹沟槽基础上进行加工,工件安装定位时轴向不易定位,同时很难保证主轴零位信号发生位置与原有的螺纹螺旋线起点相一致,因此需要寻求新方法以实现上述零件的数控车床加工。本文以石油钻杆接头螺纹修复加工为例,针对沿工件原有螺纹沟槽上进行数控车床螺纹加工的对刀问题,提出基于CCD传感器及数字图像处理技术获取工件位置及参数信息的方法,通过运动控制卡实现自动对刀加工。本课题结合实际情况,选用了符合要求的CCD摄像头、图像采集卡、计算机系统及运动控制卡,与数控车床实现硬件组成。通过采用CCD摄像头和图像采集卡把螺纹类工件图像提取到计算机并在屏幕上显示,然后经过图像处理方法去除图像噪声,进行图像分割、特征图像边缘提取及图像参数信息分析,求解图像轮廓点的相对坐标,测量得到工件几何参数信息。然后根据坐标系之间的逻辑关系,通过调用运动控制卡的控制函数,生成数控加工程序,辅以零位校正系统,实现螺纹加工自动对刀,最终修复损坏螺纹。通过以上研究,本文中完成了基于CCD传感器的数控车床螺纹加工自动对刀方法。该方法设计中发挥了CCD传感器非接触测量的优点,实现了采用智能寻位加工理论中的“寻位加工”替代传统的“定位加工”,高效率、高精度地完成对受损螺纹的数控车床修复加工,延长了工件使用寿命,同时也为以CCD为视觉传感器的非接触测量方法,针对数控系统中其他类型工件的在线检测加工应用提供了先例。更多还原

【Abstract】 The numerical control that broad existence is machining again on workpiece according to its original thread helical line basis in reality, like Petroleum boring bar connection thread renovation machining ,screw finish machining etc. As lathing is required to be implemented on original thread groove basis, and it is not easy to assemble the time axis fixing position, at the same time it is very difficult to ensure that chief axis zero position signal happening location point is consistent with original thread helical line Starting point, the numerically controlled lathing needs to explore new method to implement the above-mentioned accessory lathing.In this paper, take petroleum boring bar connection thread renovation machining as an example, against the emendation problem of processing the CNC lathe along trench on original workpiece thread, submit methods based on CCD sensors and digital image processing technology access to the workpiece location and parameters of information, implement automated processing emendation through Motion control card.This issue of the actual situation, selected to meet the requirements of the CCD camera, image capture card, computer systems and motion control cards, make up the hardware with CNC lathes. Through the use of CCD camera and image capture card to distill image from the thread workpiece to a computer and show it on the screen, remove image noise with the image processing methods, image segmentation, feature extraction and image parameters information analysis, solving image contours Point the relative coordinates, get workpiece geometry information via measuring. According to coordinate relations between the logic, motion control card by calling the control function, generate NC procedures, combined with zero signal correction system, and automatic processing thread of emendation, to finally repair damaged threads.Through study above, completed the methods based on the CCD sensor CNC lathes thread on the automatic processing knife methods. This designed methods display the advantages of a CCD sensor non-contact measurement, implement that replace from "searching processing" of intelligent search processing theory to traditional "targeting process", high efficiently, high-precisely completed repair processing of the damaged threads Controlled lathes, and extended the life of the workpiece, also provide a precedent for the visual non-contact measurement method of CCD sensor, against other types of numerical control systems online workpiece detection processing applications.更多还原