On-line geometry measurements for complex profile extrusions. (Process Machinery).The problem Historically, the measurement systems of choice for complex profile extrusion lines have been non-contact optical width gauges. Traditionally, these operate on the principle of measuring the shadow cast by the extrusion when presented under a sweeping point of laser light. The duration of the light blockage blockage of intestine, urethra, etc. See obstruction under anatomical location, e.g. intestinal, urethral. blockage Wax, see there (shadow) is precisely timed. The duration of this blockage can then be converted into a width. The precision of such systems is largely influenced by the dynamics of the rotating mirror. In the ideal scenario, measurements are performed at both ends of an extrusion and curing line. They are performed at the cured end of the line for final product dimensional validation and set-point feedback. They are performed at the hot end of the line to provide more tightly coupled See tight coupling. closed-loop process control, with the set-point established by the measurements at the cured end of the line. The challenge is that many seals have critical features that cannot be recognized with a shadow measurement principle. Multiple compound products, products with inserts and post extrusion processes such as flocking are also problematic for shadow measurement. Generally, for these types of extrusions, the process feedback is limited to a human operator who manually gauges the final cured product with an optical comparator comparator Instrument for comparing something with a similar thing or with a standard measure, in particular to measure small displacements in mechanical devices. In astronomy, the blink comparator is used to examine photographic plates for signs of moving bodies. or digital micrometer micrometer (mīkrŏm`ətər, mī`krōmē'tər). 1 Instrument used for measuring extremely small distances. . In many cases, this is done with off-line gauging instruments. What is needed to overcome these issues is an on-line profile gauge capable of measuring multiple key dimensions at the hot and cold ends of the extrusion line. Such a system will provide the following opportunities for value enhancement: * Recognize and respond to dimensional variation in key geometrical features not recognizable with other on-line measurement technologies. * Enable automatic process feedback control, especially on multiple extrusion line processes. * Enable faster startups, and thereby reducing scrap and increasing yield. * Provide continuous quality data records to meet internal and external quality program requirements. * Improve the overall dimensional quality of all extrusions by not only reducing the number of non-conforming products, but making good products better. The customer Poppe Poppe is a surname, and may refer to:
This page or section lists people with the surname Poppe. & Co. of Giessen, Germany, a developer of advanced control and processing techniques for rubber and plastic, manufactures automotive and industrial rubber products. In 1997, Chris Wooge, technical director of Poppe & Co., recognized potential value in the profile measurement technology that Bytewise Measurement Systems was providing to the tire industry. Bytewise was offering a line of laser-based non-contact geometry measurement systems that provided value through cost reduction, throughput enhancement and quality improvements. Wooge inquired about the applicability of the Bytewise technology to the on-line real-time measurements of extruded complex profile geometry. At the time of the initial discussion, the Bytewise family of products was built upon single-point laser triangulation sensors Optical Triangulation Sensors Optical Triangulation Sensors are commonly used to provide door mounted safety detection on swinging automatic doors. In North America, these types of sensors are very common and manufactured in very high volumes. . Specifically, the extrusion measurement products were designed for the off-line thickness measurement of extruded tire components, which are relatively flat on the bottom side and have a contour contour or contour line, line on a topographic map connecting points of equal elevation above or below mean sea level. It is thus a kind of isopleth, or line of equal quantity. on the top side. Complex profiles, by contrast, generally are multi-sided contours Contours may mean:
The new process control system utilizes neural network neural network or neural computing, computer architecture modeled upon the human brain's interconnected system of neurons. Neural networks imitate the brain's ability to sort out patterns and learn from trial and error, discerning and extracting processing and has been proven to work with multiple measurement system inputs and multiple control system outputs. The key missing link in the neural net neural network also neural net n. A real or virtual device, modeled after the human brain, in which several interconnected elements process information simultaneously, adapting and learning from past patterns. Noun 1. based control system has been the real-time on-line profile monitoring measurement system. In November of 2001, the first Profile 360 production system was installed at a Poppe manufacturing plant in Giessen, Germany. The solution The Profile 360 system utilizes either two or four sheet-of-light triangulation triangulation: see geodesy. The use of two known coordinates to determine the location of a third. Used by ship captains for centuries to navigate on the high seas, triangulation is employed in GPS receivers to pinpoint their current location on earth. profile sensors. The sensors each take a snapshot simultaneously. The profiles are transformed into a common coordinate system coordinate system Arrangement of reference lines or curves used to identify the location of points in space. In two dimensions, the most common system is the Cartesian (after René Descartes) system. and sent to a measurement server software component that per forms a best-fit match to a reference measurement or CAD template and calculates values for virtual calipers which have been defined. Virtual calipers allow for key dimensions of the profile to be extracted. Target and tolerance values are associated with each key dimension. Numerical outputs are available from the virtual calipers as analog signals An analog or analogue signal is any time continuous signal where some time varying feature of the signal is a representation of some other time varying quantity. It differs from a digital signal in that small fluctuations in the signal are meaningful. , RS232 data records or PLC network interfaces. The measurement server results are made available for distributed operator interfaces. Multiple operator interfaces can be running on Win32 platforms showing the current measurement results. This allows the operators at both ends of the process line to see the current measurements. Supervisory and engineering personnel located throughout the facility with network access to the measurement server can also see the measurements. The operator interface software presents the cross-section template (either CAD or reference measurement data), the measured profile and virtual calipers. Additionally, a powerful on-line comparator view can be enabled which shows the deviation from the current measure and the template in a powerful, intuitive form. A vector from each measurement point to the nearest template point is established. This vector is then drawn with a magnification Magnification A measure of the effectiveness of an optical system in enlarging or reducing an image. For an optical system that forms a real image, such a measure is the lateral magnification m factor that allows it to be visualized on a higher scale than the raw data. The error vector is color coded Noun 1. color code - system using colors to designate classifications code - a coding system used for transmitting messages requiring brevity or secrecy with green, yellow and red to indicate tolerance conformance con·for·mance n. Conformity. Noun 1. conformance - correspondence in form or appearance conformity agreement, correspondence - compatibility of observations; "there was no agreement between theory and . Different tolerances can be established for each segment of the template. Summary Profile 360 technology has demonstrated the ability to capture key dimensional features that cannot be obtained by traditional techniques, in an on-line and real-time application. Poppe & Co. is implementing new quality programs designed to reduce cost, improve dimensional accuracy and better serve their customers. This project demonstrated the successful outcomes that can emerge from two companies looking outside their respective industries for solutions to problems and for products to develop. [FIGURE 1, 2, 3, 4 OMITTED] |
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