过程控制专业翻译 电气院.doc

The translation of pp.597-611 ,Section C to G，Handbook of Manufacturing processes C. Manufacturing Cells (Group Technology)(Family of Parts Concept)The use of manufacturing cells represents a particular kind of factory layout for manufacturing equipment. The essence of the concept is that, when manufacturing a particular part or family of similar parts in substantial quantities, the equipment for successive operations on the part should be grouped together. The operator - or team of operators who make that part (or the family of parts) - operate all the equipment in the cell. This arrangement is in contrast to a more traditional factory layout that groups like equipment together in departments. Then parts move from department to department for each operation. The advantage of the cell layout is that lines of communication and transportation are made very short. The factorys through-put rate is speeded; work-in-process inventory is greatly reduced; when problems arise at one operation, their effect on subsequent operations is immediately recognized. Route sheets to control movement of parts through the factory are greatly simplified or not needed. Operators learn what is needed at each operation to avoid problems at subsequent operations and have the satisfaction of seeing the results of their efforts. Quality tends to improve. The dis advantage is that there is apt to be lesser utilization of some equipment. There is also the necessity of having operators learn the operation of several kinds of equipment rather than specializing in one type. The concept is illustrated in Fig. 14C for one particular family of machined parts. Fig. 14G8 shows a more advanced system where a robot does the handling between operations. When a circular layout is used, the robot can tend all machines in the cell.C.制造单元（组合工艺）（元件簇的概念） 制造单元的使用代表一些工厂对制造设备独特 的布局，这一概念的实质是当制造较大数量的特殊元件或者大量相似零件簇，对于部分进行连续操作的整体应该组合起来，那些制造元件（或元件簇）的操作员或操作团队将所有的设备运营成一个单元，这一安排跟那些设备都聚集在一个部分的较为传统的工厂布局是相反的，因此每一个操作都要把元件从一个部门移到另外一个部门。单元布局的优点就是交通运输线变得很短，工厂的流通性得以提高；在制品的存货大大减小；当在某个环节出现问题时，随后的环节就会立马意识到。贯穿工厂控制各个部分的运作线路被大大简化或者被取消。操作员知道在每个操作中需要做什么去避免在随后操作中出现的问题，然后根据看到的效应给予补偿。使质量趋于完善。它的缺点是对于一些设备的利用有变少的趋势。因此让操作员学习多种设备的操作也是很有必要的，而不是专门操作一种设备，这一概念在Fig.14c中关于零件的特殊簇进行了阐述。Fig.14G8展示了一个由机器人进行各种操作的更先进的系统。当使用循环布局时，在单元内，机器人可以照管所有的机器。XXXIFig. 14C The concept of a manufacturing cell illustrated with a cell arranged to make a family of spur gears of various pitches and diameters from forged blanks . This cell is shown with one operator for seven operations,based on the use of automatic equipment. A similar arrangement may be made using more operators and possibly duplicate machines for some workstations depending on the production level needed, and the operation time at each workstation. The gear blanks are first faced on both sides, turned, drilled and reamed at station one. At station 2, a keyway is broached in the center hole. At station 3, the gear teeth are hobbed and at station 4, they are finish shaved. Stat ion 5 is a brush deburrer. At stat ion 6, the gear is laser- marked to identify its model or part number, and with other descriptive Fig.14C制造单元的概念被阐述为由一个单元排列成锻造栏中由各种强度和直径的传动齿轮组成的簇。基于自动设备的使用，这个单元显示一个操作员对应七个操作。由于生产标准的需要和每个工作站的操作时间，对于一些工作站，类似的布局可能使用更多的操作员，或者可能增加成倍的机器。在站1，齿轮栏两侧首先会经过转动，钻铰。在站2，在中心孔钻出键槽。在站3，齿轮齿滚齿。在站4，完成修面。在站5,是一个刷子去毛机。在站6，用激光标识齿轮的型别或零件序号，和其它描述性数据。在站7，各种量具和检测设data. At station 7, various gages and inspection devices are used to ensure that quality is of the pre scribed level. The small tables between machines act as decouplers/Kanbans, containing small amounts of work- in- process, to illustrate which machines may need operator attention to maintain production flow. Ideally, these tables are empty and all work-in-process is undergoing machine operations.D.Advanced Inspection DevicesDl. coordinate measuring machines (CMMs) utilize diffraction gratings to gauge the position of a measuring probe with high accuracy. Typical systems include, in addition to the measuring machine, a sensing probe, a control and computing system and measuring software. Various kinds of probes may be used. The probe is moveable with very low friction because of nearly friction-free linear bearings in the machine. The workpiece to be measured is placed on the granite table and is then stationary. The electronic touch probe is guided to move around the workpiece and make contact with it where measurements are wanted. Probe movements can be in the x, y, or z direction.Movement of the probe can be manual, by CNC, or by a programmable controller. The readout console displays the position of the probe simultaneously in terms of the three coordinates. Different probe shapes can be used, depending on the element that is being measured.For example, if dimensions involving the center axes of holes are to be measured, a tapered plug is used as the probe. The measurement accuracy results from use of the moire fringe pattern from two glass scales placed together on the machine at a slight angle from each other. The fringe pattern between the scales is detected by photocells and converted to electrical pulses. Measurement accuracies within 2 to 4 ten-thousandths of an inch in a span of 10 to 30 inches are common. The probe is often mounted on a bridge like structure, but may be cantilever mounted or fastened to an articulated arm. The machine is usually installed in a room in which temperature and humidity are controlled. 备用于确保质量达到预估水平。机器间含有少量的在制品的小桌子充当分离板，说明这个机器需要操作员注意保持生产流程。理念上，这些台子是空的，所有的在制品都在进行机器操作。D.先进检查装置 D1.坐标测量机（CMMS)-利用光栅衍射测量具有高精度的测量探针的位置。典型系统包括除测量机器之外，还有感应探针，控制和计算系统，以及测量软件，可能用到各式各样的探针。可移动的探针具有很小的摩擦力，因为在设备里面几乎无摩擦的线性关系。被测量的工件被安放在花岗岩台上，所以固定性是很好的，电触探针被引导翻转工件，然后与所需要测量的地方进行接触，探针可以在xyz三个方位进行移动。探针的移动可以是手动控制，或者通过CNC控制和可编程的控制器控制。读出器控制台显示出在这三个方位的探针坐标，不同规格探针的使用取决于所在测量的元件。例如，如果被测量量是洞中间的刃，那么锥形的栓子就被作为探针。测量的准确性是由显微镜中的云纹模具所决定的，它们在设备上被放置在一起，云纹模具在各种领域中被发现通过光电池，然后转化为电子脉冲，在测量10到30英寸时，有2%到4%的测量误差是正常的，探针通常装置着类似建筑物的桥，但是也可能是装备有悬臂或者配备了一个可活动的手臂。这个设备通常配备在一个温度和湿度可控，坐标，纵切面，角度可测量的房间内。有些设备装备有不止一个探针，或者具有视觉装置，或者是激光扫描装置（如下），除了接触探针以外，一些设备涉及到各种感应系统。Coordinate, profile, and angular measurements can be made. Some machines are equipped with more than one probe or with a machine vision device or laser scanner (see below), in addition to a contact probe. Such machines are referred to as multisensor systems. Fig. 14D1 illustrates a typical coordinate measuring machine.Fig. 14D1 Dimensional inspection of a machine component with a coordinate measuring machine. (Courtesy Sheffield Measurement, Inc.)D2.machine vision - in industry, utilizes a pictorial image of the workpiece as part of a system of quality, machine or process control. Control is accomplished by capturing the image by electronic methods and then using digital data of the image, as the data is processed by a computer, to provide a display, to sort good and bad parts or to actuate control mechanisms. Machine vision systems are versa tile and have many non-manufacturing applications in the fields of medical diagnosis,surveillance, zip-code mail sorting, Fig.14D1图解了一个典型的坐标测量机。Fig.14D1 具有坐标测量机的机器尺寸测量。(谢菲尔德测量)D2.视觉设备，在工业中，利用工件的生动形象的描绘作为一个质量体系或者过程控制的一部分。控制的实现是通过电子方法来获取图像，然后利用图像的数字信号，数据通过电脑处理显现后，把好的和坏的进行分类，或者激励控制机械。机械视觉系统是有多种功能的，在医疗诊断，检测领域，邮政编码的分拣，交通控制和条形码阅读这些领域中有许多非制造业的应用traffic control, and bar code reading.A machine vision system includes means for proper illumination of the workpiece or scene to be pictured, a camera or cameras, an analog to digital converter (though some systems process digital data directly from the camera), sufficient computer stages to process the data, computer software for the application, and actuating equipment that responds to the digital signal from the computer. Proper lighting is a critical factor and there are various lighting arrangements: backlighting, low angle lighting or diffuse lighting to emphasize the essential image elements. Fig. 1402 illustrates the elements of a typical industrial vision system.机械视觉系统包括对工件或场景来进行合适的描绘。照相机或者摄像机，A/D转换器（尽管一些系统直接从相机得到过程数字信号），充分的计算机阶段处理数据，电脑应用软件，和处理来自计算机的数字信号的响应设备。适当的灯光是一个关键的因素，因此有各种各样的照明设计：背光，低角度灯光或者强调基本图像元素的漫射灯光。Fig.1402阐述了一个典型的工业视觉系统。Fig. 1402 major elements of an industrial machine vision used for inspection or control.图1402 用于检测和控制的工业机器视觉的主要元素Image processing removes unwanted detail. What detail is wanted and what is not wanted is a result of segmentation, the procedure of choosing the elements that must be measured to achieve the desired results. Segmentation reduces the amount of data that must be computer processed, speeding up the operation of the system. One common form of segmentation is to concentrate on the edges of the image, the changes in contrast that are characteristic of the edges of the workpiece or the edges of a shadow of a three-dimensional workpiece. (This localized analysis is one reason why proper illumination is critical.) Unexpected edges may be evidence of a surface flaw or other defect in the workpiece. Another segmentation approach is to scan with the camera only a narrow strip across the workpiece instead of its full area, if that is enough to make the desired measurement. Another is to analyze only a small critical portion of the whole image. Even with segmentation, because of the large amount of data in each picture image, high-capacity computer systems are required. The camera includes a lens system to focus the light and a CCD (charged coupled device) integrated circuit that receives the camera image (instead of photographic film that would be used in a film camera). Each pixel (picture element of the CCD sensor) in the camera senses the brightness of light focused on it. The brightness level at each significant pixel is converted to a binary digital number that is processed by the systems computer. Most machine vision cameras are monochromatic, so the brightness value is from a grayscale.Color filters may be used on the camera, however, or color cameras may be used, when color is an important factor in the particular application. All inspection and machine control operations involve computer analysis of the image data. This analysis may involve such things as counting the number of pixels between two lines or edges, determining the radii of some curved edge, counting the number of pixels in the entire image,etc. After such analysis, these measurement data are compared with the data stored in the computer that defines a 图像处理，除去一些不必要的元素。选择测量必须得到预期效果的元素程序，什么元素必要什么元素不必要是分割的结果。分割降低了必须进行计算机处理的数据量，加快了系统的运行。分割的一般形式是聚在图像的边缘。相对而言，是工件或者阴影的三维工件边缘特性的变化。（这些局部分析是为什么适当的灯光是至关重要的原因之一）。工件上一些非期望的边缘可能作为表面缺陷或其他缺陷的证据。另一个分割方法是用相机扫描穿过工件的一个窄条，而不是它的所有区域，前提是这个方法足以得到欲求的测量。另一种是只分析整个图像中关键的一小部分。因为每个图像中有大量数据，所以即使分割，也需要大容量的计算机系统，相机包括一个透镜系统去聚焦光线和一个CCD集成电路来接受相机图像（而不是被用于胶片机中的胶片）。每个相机中的像素（CCD传感器的图像处理）感知到聚集在它上面光的亮度。经过计算机处理。大多数机械视觉相机是单色的，所以亮度值是由灰度来决定,然而，在特定的应用中，当颜色作为一个重要因素时，相机可以使用彩色滤光片，或者使用彩色照相机。所有的检测，机器控制操作都涉及到图像数据的计算机分析。这种分析可能涉及到类似计算两线之间或者边缘的像素数。确定一些曲面的半径，来计算整个图像的像素数。经过这样的分析，这些测量数据与储存在计算机中定义标准模式或者被测量值得数据进行比较。根据两组值的差异，机械或者过程控制可能被调整，也有可能零件被舍弃。standard pattern or value for the characteristic being measured. Depending on the difference between the two sets of values, machine or process controls may be adjusted or parts may be rejected.The advantages of machine vision systems compared with human visual inspection or control are the much greater consistency and reliability of measurement that are inherent in the machine sys tem. Also, machine vision does not suffer from fatigue, can operate in adverse working conditions and can often be operated at higher speeds than a human counterpart.When used for component inspection, machine vision can provide several different types of information: 1) part identification, 2) the presence or absence of a component or certain features, 3) shape verification, 4) measurement of length, width, area, hole diameter and hole position 5) inspection of surface finish including surface flaw detection. 6) quantity verification when multiple components are involved.One machine control application is the guiding of robots. Machine vision on a robot can guide the robot to locate the part, then identify it, then direct the robots gripper to the proper position to grasp the part correctly, and then, after it is grasped and moved to the desired location, orient the part to fit the receiving space. Other applications of machine vision are inspections made throughout the electronics industry for both circuit board and integrated circuit manufacture. Specific examples are inspection of circuit path widths, completeness of population of boards and soundness of solder joints. Machine vision provides feedback control data in wire bonding and die slicing operations. In the paper, textile and plastics industries, machine vision monitors the soundness of continuous webs of rapidly-moving material during processing, including the Completeness of coatings applied. In high-production printing, it monitors the和人类视觉检测或者控制相比，在机械系统中，机械视觉系统更具有一致性和固有的测量准确性。同时，机械视觉不会感觉到疲劳，可以在恶劣的工作环境中运行，可以用更高的速度运行人类相应的操作。当运用与于成分检测，机械视觉可以提供几种不同类型的信息：1）局部识别：2）成分或者某些特征是否存在；3）形状检测；4）长度，宽度，面积，孔直径和孔的位置的测量；5)包括表面光洁度的表面检测；6）涉及多个组件的数据验证。机器人引导是机器控制中的一种应用。机器人上的机械视觉能够引导机器人进行定位并且识别，然后引导机器人手臂到达适当的位置准确抓住部件，部件被抓取后被移到预定位置并确认部件与接收部分完全契合。在电子工业中，机械视觉应用于电路板或集成电路制造的检测。具体的例子有电路路径宽度以及板和焊点群的完全性检测。在引线键合和模具切片操作中，机械视觉提供反馈控制数据。文献中记载，纺织和塑料工业，机械视觉显示了快速连续移动材料在加工中连续网络的可靠性，包括在完整涂料中的应用。在高批量印刷生产中，它监视打印文档上不同颜色的登记。在食品工厂中，机械视觉识别并舍弃在袋装饼干和糖果以及类似产品中过小，过大，或者畸形的产品。对于许多产品，验证标签被准确的置于容器上。在各种产品的包装绘制上，从它的运行或者其它缺陷上确定适当的光泽，颜色，覆盖范围以及自由度。在利用高度自动的玻璃，塑料以及金属制造工艺中，机械视觉从制造的单个零件中发现缺陷并且显示制造容器completeness of coatings applied. In high-production printing, it monitors the registration of different colors on the printed document. In the food industry, machine vision identifies and rejects undersize, oversize or misshapen products in the packaging of cookies, candy bars, and similar products. For many products, it verifies that labels are properly in place on containers. In the painting of various products, it confirms the proper gloss, color, coverage and freedom from runs or other defects. Machine vision finds flaws in individual parts made with highly automatic glass, plastic and metal manufacturing processes, and monitors the quality of manufactured containers.D3.laser scanning- is a method used for dimensional inspections. In one common technique, the workpiece is placed between a low-power scanning laser beam and a photodetector. Scanning is achieved by directing the beam to the axis of a rotating mirror which reflects the image to different points on a collimating lens. The axis of the mirror is at the focal point of the lens. The lens directs the parallel beams to a collecting lens that focuses the beams on a photodetector. A workpiece is placed between the two lenses.The collecting lens receives the beams that pass the workpiece but not those that strike the workpiece and cast a shadow on the collecting lens. The dimensions of the shadow, and thus the workpiece, are calculated by the timing of the spaced laser beams on each side of the shadow. A microprocessor makes the necessary calculations and displays the width or other work piece dimension of interest. Fig. 14D3 illustrates the working principle. Since there is no contact between the workpiece and measurement tools, the procedure is useful for in-process measurements.Workpieces can be measured while they are in motion on a machine or conveyor. Multiple parts can be measured simultaneously by the one beam. Bench-mounted laser micrometers are also used. Accuracies of 10in (0.25m) are achievable for dimensions of 2 in (50 mm) or less. For larger dimensions, measurement tolerances are correspondingly large的质量。D3 激光扫描是一种用于尺寸检测的方法。在通常的手法中，工件被放置在一个低功耗激光扫描器与探测器之间。扫描是通过引导光束到直透镜上反射图像到不同点的旋转镜轴上实现的。镜子的轴在镜头的焦点上。在探测器中，透镜引导光束到聚集光束的会聚透镜。工件被放在两个透镜之间，会聚透镜接受那些通过工件的光束，而不是撞机工件的光束和在会聚透镜上留下阴影的光束。从而通过激光束的时间间隔和每一面的阴影计算出工件以及阴影的尺寸。然后微处理器进行必要计算并且显示出所需的宽度或其它工作片尺寸。图Fig.14D3图解了工作原理。由于在工件和测量工具之间没有联系，所以在过程测量中程序是很有用的。当它们在运作的机器或者传送器上时，工作片也可以进行测量。多个部分通过一束激光来测量。固定激光器“微米”也被使用，对于在（50mm）或者更小的二维中，精度在10m（0.25m）是可以的。对于大尺寸测量，测量误差相对来说也较大。In another system, the scanned laser beam is received by an array of photodiodes instead of a single photocell. Depending on the location of the edges of the workpiece, some diodes receive the laser beam and some do not. From these differences in the signals received, the dimensions of the part can be determined.Another measurement aims a laser beam at a curved surface and records the reflections.在另一个系统，扫描激光束是一系列光电二极管而不是单个的光电池接受。根据在工件的边缘位置，部分二极管接受激光束，部分不接受。从这些接收信号的差异，部分的尺寸可以被确定。另一种测量是指位于曲面上的激光束记录反射。Fig. 14D3 The working principle of laser scanning for dimensional measurement. The dimensional measurement is based on the elapsed time between the detection by the photodetector of the laser beam from each side of the workpiece.Thousands of points per second are scanned and the resulting data describes the curved surface in detail. The units computer compares these data with the specified dimensions and indicates whether or not the shape meets specifications.Still another system uses interferometry. In this method, a laser beam is split into two separate beams by a partially silvered mirror. One beam travels to a fixed mirror and the other to a movable mirror on the workpiece to be measured. The beams are combined and the visual pattern of the interference of the two beams is fed to a photoelectric detector and digital counter. The图14D3 激光扫描尺寸测量的工作原理。尺寸测量是基于光探测器的工件每测得激光束在工件之间进过的时间。以十点每秒的速度扫描产生的数据来描述曲面的细节，单位计算机将这些数据与指定的尺寸和形状进行比较，然后看是否符合规格。而另一个系统使用干涉法。在这个方法中，激光束通过局部镀银镜被分散成两个独立的光束。一束被传送到一个固定镜，另一个被传送到被测量工件的移动镜。光束被聚合，然后以光的干涉视觉模式被反射到光电探测器和数字计数器。光条纹数表明移动number of light fringes indicates the displacement of the movable mirror. The method is very accurate and is used in measuring the accuracy of, and in calibrating moveme