This application relates to systems and methods for the detection of orientation features on a material web.
During the handling and processing of web-shaped materials, guiding controls for webs are deployed. Material webs, for instance, can be fed into a machine, processed and subsequently rewound by using a winding device, whereby various positioning errors may occur. In order, for example, to guide the lateral offset of a material web, appropriate control devices can be used.
This deviation can influence the measuring result of a sensor that is located in the area of the outlet length. In an embodiment for a web guiding control an additional roller may be located in the area of the outlet length, in order to adjust the deviation and hold the material web in the further course of the outlet length on its predetermined material web level S. Thus a constant gap distance from the material web to the sensor may be kept in the further course of the outlet length, and a precise measurement of the material web with conventional sensors made possible. However, the material web may be warped or wrinkled by the support roller. The use of an additional roller may also be cost-intensive.
This application relates to systems and methods for the detection of orientation features on a material web.
Disclosed, for example, are devices and methods for the detection of at least one orientation feature on a material web, which runs on a predetermined material web level in the predetermined travel direction of the material web.
In terms of one aspect the device involves a sensor device, including a sensor element with at least one sensor line for the registration of a sensor zone on the material web. Additionally, the device involves at least one light transmitter to produce a beam spot on the material web, in order to determine the position of a material web level that shows a deviation from the predetermined material web level. Thus, in some embodiments, the position of the deviating material web level can be determined in a simple and cost-saving way, and a simple and precise detection of at least one orientation feature can be made possible.
The device may show one or more of the following features in various embodiments. The material web level that shows a deviation from the predetermined material web level may be a material web level turned around its axis running in the travel direction of the material web. The light transmitter (at least one) can be developed in such a way that the beam spot (at least one) in the sensor zone lies on the material web. The sensor device can be developed in a way that the sensor element registers the (at least one) light beam on the material web to determine the position of the deviating material web level. The light transmitter can be developed in order to produce at least two beam spots on the material web. In this case the light transmitter can, additionally, be developed in such a way that at least two light spots on the material web are preferably in a line, which runs vertically to the predetermined travel direction of the material web. The light transmitter can be developed in such a way that the (at least two) light spots on the material web along the predetermined material web level show a first distance. Additionally, the light transmitter can be developed in such a way that the (at least two) light spots on the material web along the deviating material web level show a second distance. In such a case the sensor device can be developed in such a way that the sensor element registers the first and second distance to determine the position of the deviating material web level. The device may involve appliances to analyze the difference between the first and second distance in order to determine the position of the deviating material web level. The light transmitter can be developed in such a way that (at least two) light beams that run parallel to each other are being created which produce (at least two) light spots on the material web. For this purpose the device can involve (at least two) light transmitters that are arranged parallel to each other. In some embodiments, the device may involve one light transmitter and a beam divider arrangement in order to produce the (at least two) light spots on the material web. The beam divider arrangement may involve a semi-transparent element and a reflecting element. The sensor can be developed in such a way that (at least two) sensor lines of the sensor element in the direction of the material web will be readout, at least partially, thus to achieve an integration effect at the sensor zone of the material web in the travel direction of the material web. The sensor element can be arranged in a slanted position toward the predetermined material web level.
In terms of another aspect the device involves a sensor device, which includes a sensor element with at least two sensor lines, for the registration of a sensor zone on the material web. The sensor device has been developed in a way that at least two sensor lines of the sensor element in the direction of the material web are being readout at least partially. Thus an integration effect at the sensor zone of the material web in the travel direction of the material web may be achieved. The use of additional integration devices for the widening of the sensor zone in the direction of the material web may generally not be required. In addition the number and scope of the sensor lines, the partial section of the sensor lines to be readout, may be chosen flexibly.
The device may show one or more of the following features in various embodiments. The sensor device can be developed in such a way that only a partial section of the sensor lines of the sensor element is being readout at least in part. In particular the sensor can be developed in such a way that 1/10 or less of the sensor lines of the sensor element will be readout at least in part. The sensor device can be developed in such a way that the sensor element can be readout at a frequency between 50 and 1000 Hz, in particular at approximately 200 Hz. The material web level that shows a deviation from the predetermined material web level may be a material web level turned around its axis running in the travel direction of the material web. The device may involve at least one light transmitter to produce at least one light spot on the material web to determine the position of the material web level deviating from the predetermined material web level. The sensor device can be developed in such a way that the sensor lines of the sensor element in a sensor zone will be readout in the periphery of the (at least) one light spot. The sensor element can be arranged in a slanted position toward the predetermined material web level. In this case the sensor device can be developed in such a way that the partial section of the sensor lines depends on the position of the deviating material web level.
In terms of a further aspect the device involves a sensor device which includes a sensor element with at least two sensor lines for the registration of a sensor zone on the material web, whereby the sensor element is arranged in a slanted position toward the predetermined material web level. As a result a partial section of the sensor lines to be readout can be selected dependent on the position of the material web level. This may make autofocusing possible without the use of additional focusing appliances.
The device may show one or more of the following features in various embodiments. The sensor device can be developed in such a way that at least two sensor lines of the sensor element will be readout in the travel direction of the material web at least partially, so to achieve an integration effect at the sensor zone of the material web in the travel direction of the material web. The sensor device can be developed in such a way that only the partial section of the sensor lines of the sensor element will be readout at least partially. The material web level that shows a deviation from the predetermined material web level may be a material web level turned around its axis running in the travel direction of the material web. In addition, the device may involve at least one light transmitter to produce at least one light spot on the material web to determine the position of the material web level deviating from the predetermined material web level. The sensor device can be developed in such a way that the partial section of the sensor lines depends on the position of the deviating material web level.
In addition, in terms of one or all of the aspects named above, the device may show one or several of the following features. The light transmitter (at least one) can be a monochromatic light source, for example, a laser. Furthermore the device may include an optical element, for example, a lens, which is to be arranged between the sensor element and the material web. In some embodiments, the sensor device can be developed in such a way that the magnification ratio of the sensor device can be larger than 1:2.
The device may further involve a focusing element, which is arranged between the sensor element and the material web. The focusing element can be developed in such a way that it will change the optical element, depending on the determined position of the deviating material web. The (at least one) orientation feature can be a line or a pattern on the material web. The (at least one) orientation feature may also be an edge of the material web. The sensor device can be developed in a way that the sensor element will detect differences in brightness and/or color of at least one orientation feature. Moreover, the sensor element can also be a CMOS matrix sensor.
In terms of one aspect the method includes
In terms of a further aspect the method comprises
The embodiments may provide any, all or none of the following advantages. Through utilization of at least one light transmitter, in order to produce at least one light spot on the material web, the position of a deviating material web level may be determined in a simple and cost-saving way. Thus, in some embodiments, a simple and precise detection of at least one orientation feature on the material web may be made possible. With the readout of at least two sensor lines of the sensor element in the travel direction of the material web an integration effect may be achieved. The use of additional integration devices for the widening of the sensor zone in the direction of the material web may generally not be needed. In addition the number and scope of the sensor lines, the partial section of the sensor lines to be readout, may be chosen flexibly. By arranging the sensor element in a slanted position toward the predetermined material web level, the partial section of the sensor lines to be readout can be selected depending on the position of the material web level. This may make autofocusing possible without the use of additional focusing appliances.
Following is an explanation based on exemplary embodiments with reference to the attached drawings.
In a device, e.g., for controlling the lateral offset of a material web, at least one orientation feature can be used to determine a lateral deviation of the material web from a predetermined position. This can be at least one orientation feature, for instance a line or a pattern on the material web. The orientation feature may run in the travel direction of the material web and can be located near the edge of the material web or be the edge itself. The sensor elements in this case can be optoelectronic sensors, such as color sensors or cameras.
The (at least one) orientation feature can, for example, also be an edge of a material web or something similar.
If the subsequent description does not specify anything to the contrary, the sensor element may thus have the following embodiments. For instance, the sensor element can be a CCD sensor or a CMOS sensor. The sensor element can be a line sensor, such as a CCD line sensor. The sensor element may, however, also be a matrix sensor, such as a CCD matrix sensor or a CMOS matrix sensor.
The sensor element can be a black & white camera or a monochrome camera. The sensor element may also be a color sensor, registering pixel by pixel, which may use an RGB evaluation. With each sampling the light is broken down in the basic colors red (R), green (G) and blue (B). With the aid of an algorithm the differences in contrast may then be evaluated by a calculation unit, such as a processor, and the position of the orientation feature may be displayed. The contrast, as mentioned above, can also be calculated from the differences in brightness.
When determining the position of the orientation feature 340 on the material web, the position of the orientation feature 340 can be registered within the sensor zone 308. If the material web, as shown in
To produce the two light spots 334, 335 (or respectively 334′, 335′) two light beams 332, 333 running parallel to each other are shown in
Determining the position of the deviating material web level may be achieved with only one light spot as well. Determining the position of the deviating material web may, for example, then be made by triangulation. It should be equally understood that several (more than the two as illustrated in
The sensor device 470 involves the sensor zone 408 on the material web 400 in order to detect the (at least one) orientation feature there. If the material web 400, in the range of the outlet length, by pivoting at a particular angle around pivot point A, is brought off the predetermined travel level of the material to a deviating material web level, then the distance between the material web and the sensor element 470 is no longer constant. This deviating position of the material web may now be determined by using light transmitter 430. The light transmitter 430, with the aid of beam divider arrangement 436, 437, may create two parallel beams that produce two light spots in the sensor zone 408 on the material web 400. The position of the deviating material web level may be determined in an easy and cost-saving manner, and a simple and precise detection of at least one orientation feature on the material web may be made possible.
The distance of the two light spots can be registered by the sensor device 470. A corresponding signal can then be given by the sensor device 470 to the controlling device 450. The controlling device, considering the signal, may then determine the lateral offset of the material web 400 and may actuate the drive device 460 accordingly.
The light transmitter 330 can be a monochromatic light source, for example, a laser. Other appropriate light transmitters, however, can be used as well. If a laser is being sent out, the laser may be switchable. In this case the sensor device can register the sensor zone at a first point in time, when the light transmitter is switched off and no light spots are present. At a second point in time the sensor device can register the sensor zone when the light transmitter is switched on and the light spots in the sensor zone are present. Then the difference between the data records of the first and second point in time can be sampled. Thus the recognizability of the spots on the material web may be improved.
With the sensor device 570 as shown in
The material web 500 can, by using an offset device, be offset to a material web level that deviates from the predetermined material web level, as previously illustrated. The device may also further involve a light transmitter to produce at least one light spot on the material web in order to determine, as previously illustrated, the deviating material web level. The sensor lines of the sensor element 571 in a sensor zone 508 in the periphery of the (at least) one light spot can then be readout.
The magnification ratio of the sensor device 570 can be larger than 1:2. Our magnification ratio is to be understood as the ratio between image distance b and object distance g. Here the image distance can be the distance between the sensor element 571 and the optical element 572. The object distance g can be the distance between the material web 500 and the optical element 572. A magnification ratio larger than 1:2 results in the object distance g being more than twice as large as the image distance b. The magnification ratio can be in a range of 1:4 to 1:10.
The device may further involve a focusing element 573, which is arranged between the sensor element 571 and the material web 500. The focusing element may involve a piezoelement, for instance. With its help, the optical element 572, for example, can be offset in a direction parallel to the principal axis of the object lens, and can thus effect a focusing by changing the image sharpness. The magnification ratio is thus being changed as well.
In case of a deviation of the material web from the predetermined material web level, the focusing element 573 can change the optical element, the lens 572, depending on the determined position of the deviating material web. Especially in the sensor device 570, as illustrated in
It should be understood that the various aspects illustrated with reference to
Number | Date | Country | Kind |
---|---|---|---|
EP08151610.6 | Feb 2008 | EP | regional |
This application claims priority under 35 U.S.C. §119 to European Patent Application No. EP08151610.6, filed Feb. 19, 2008, the contents of which are hereby incorporated by reference in its entirety, and under 35 U.S.C. §119 to U.S. Provisional Patent Application No. 61/041,297, filed on Apr. 1, 2008, the contents of which are hereby incorporated by reference in its entirety.
Number | Date | Country | |
---|---|---|---|
61041297 | Apr 2008 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 12370335 | Feb 2009 | US |
Child | 13906137 | US |