Method for determining a characteristic of a strip-shaped article guided through a measuring roll - Patents.com

Abstract

A method for detecting characteristics of a strip-shaped article, in particular a metal strip, guided through a measuring roll 1, comprising guiding the strip-shaped article through the measuring roll in order to detect the characteristics of the strip-shaped article, in particular a metal strip, guided through the measuring roll, the measuring roll being configured to have: a measuring roll body 1a having a circumferential surface; at least one recess 3 in the measuring roll body, the recess 3 being spaced apart from the circumferential surface or leading from the circumferential surface into the interior of the measuring roll body; and a first force sensor 7a arranged in the recess and a second force sensor 7b arranged in the recess or in another recess adjacent to the first recess, the first force sensor having a sensor surface capable of generating a sensor signal when the position of the sensor surface of the first force sensor changes; and the second force sensor having a sensor surface capable of generating a sensor signal when the position of the sensor surface of the second force sensor changes.

Description

[Technical field]

[0001] The present invention relates to a measuring roll for detecting properties of a strip-shaped article, in particular a metal strip, guided therethrough.The present invention also relates to a method for detecting properties of a strip-shaped article, in particular a metal strip, guided therethrough.The present invention also relates to the use of such a measuring roll.The present invention also relates to a force sensor for such a measuring roll or for use in such a method.

[0002] Measuring rolls are used during the cold and hot rolling of metal strips and are known, for example, from DE 42 36 657 A1.

[0003] For the conventional measurement of the flatness during rolling of a strip, essentially a method is used in which the strip is guided at a defined wrap angle via a measuring roll equipped with a force sensor.

[0004] In this way, in the measuring roll according to DE 42 36 657 A1, contact is made between the force encoder or its cover, which is arranged in a radial recess of the measuring roll that is open towards the measuring roll surface, and the strip. There is a cylindrical gap between the force sensor, which is clamped to the bottom of the recess, and the recess wall surrounding the force sensor. To prevent contamination, such as strip wear debris and lubricant, from entering the ring gap between the force sensor and the measuring roll body, this gap can be closed by sealing the shoulder with an O-ring or by sealing the front with a plastic layer. As shown in FIG. 1c of DE 42 36 657 A1, the encoder can also be arranged in a recess of the solid roll and then covered by a machined diaphragm.

[0005] The arrangement of the force sensor at a distance from the wall surrounding it and the closing of the ring gap by an O-ring or a sufficiently elastic plastic (DE 196 16 980 A1) prevents lateral forces occurring on the body of the measuring roll during rolling from acting as disturbances on the force sensor or on the measurement result. Such disturbance forces arise as a result of the strip tension acting on the measuring roll and the associated deflection of the measuring roll. In this case, the cross section of the measuring roll takes the shape of an ellipse whose major axis runs parallel to the strip. If the deflection of the measuring roll is transmitted to the encoder by force branching, it will be misinterpreted by the force sensor as an unevenness of the strip. When using sealing elements in the ring gap, such force branching cannot be completely avoided, since the sealing force necessarily acts on the force sensor.

[0006] From DE 10207501 C1 a solid roll for detecting flatness deviations during the processing of strip-shaped articles, in particular metal strips, is known, which has a force sensor arranged in a recess, which is accessible in the axial direction. The production of the axially extending recesses is often carried out by means of a deep hole drilling tool. For measuring rolls with a roll width of more than 1000 mm, in order to drill the recesses from the end side, the drilling tool must first be passed over a partly very long journal, so that a very long drilling tool must be used. This is often due to the length of the drilling path.

[0007] From DE 202007001066 A1 a measuring roll for detecting flatness deviations during the processing of strip-shaped articles, in particular metal strips, is known, which has a measuring roll body, a cover tube which at least partially surrounds the measuring roll body and a force sensor arranged in a recess, the recess extending from one end face of the measuring roll into the measuring roll body and / or into the cover tube. The recess can be closed at the end face side by a cover. The journals on each end face of the measuring roll are molded into the measuring roll body. A disadvantage of this measuring roll is that the provision of the recesses weakens the measuring roll body or the cover tube. With wide measuring rolls, the passage of the bearing journals, as in the case of deep hole drilling, is also a major disadvantage. Another problem is that the passages / grooves are not produced by a drilling tool (circular passages) as in DE 10207501 A1, but by a milling tool (polygonal passages), which leads to wear of the passages / grooves provided up to the end face.

[0008] The problem underlying the invention is to increase the information value of the inspection carried out by such a measuring roll of the properties of a strip of article guided therethrough.

[0009] This problem is solved by the subject matter of claims 1, 9, 10, 11, 12 and 13. Preferred embodiments are set out in the dependent claims and are explained in more detail in the following description.

[0010] The invention proceeds from the basic idea of ​​using a measuring roll for detecting the properties of a strip-shaped article guided via the measuring roll, in which a first force sensor is arranged adjacent to a second force sensor in a recess of the measuring roll body of the measuring roll, both force sensors being arranged adjacent to each other so close that the sensor surface of the first force sensor is directly adjacent to the sensor surface of the second force sensor, or the first force sensor is arranged adjacent to a point of the sensor surface of the first force sensor, which extends in the radial direction of the measuring roll and intersects with a point of the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor, extends in a plane that includes a line connecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and a point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and · the angle between the line intersecting the point of the sensor surface of the second force sensor closest to the sensor surface of the first force sensor is less than 65°. Alternatively, the invention proceeds from the basic idea of ​​using a measuring roll, in which the first force sensor is arranged in a first recess of the measuring roll body of the measuring roll and the second force sensor is arranged in a second recess adjacent to the first recess, both of which have an end boundary line extending in the radial direction of the measuring roll and intersecting the point of the sensor surface of the first force sensor closest to the sensor surface of the second force sensor, extends in a plane that includes a line connecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and a point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and The first force sensor is arranged adjacent to the second force sensor such that the angle between the line intersecting the point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor is less than 65°.

[0011] It is known from the prior art to arrange several force sensors in a recess of the measuring roll body. In paragraph 3, lines 1-2, of DE 10207501 A1, it is taught to arrange several force sensors in a recess at a distance from one another. FIG. 2 of US 2013 / 0298625 A1 similarly shows several force sensors arranged at a distance from one another. In paragraph

[0021] of DE 102014012426 A1, it is taught to arrange several force sensors in a recess, which is embodied in FIG. 2 of this specification by the fact that several force sensors are arranged at a distance from one another in this recess. From the prior art, it can be seen the general teaching that in the case of several force sensors arranged in a recess, the force sensors are obviously arranged at a distance from one another. The underlying principle is to distribute the (few) force sensors provided as widely as possible in the respective recesses, so that the measurements are carried out as widely as possible over the width of the possible measurement area, which is determined by the length of the recesses. Moreover, the widely spaced arrangement of the force sensors in the recesses is probably based on the idea of ​​avoiding erroneous measurements. If the forces acting in the radial direction on the measuring roll body of the measuring roll are measured by a force sensor arranged in a recess of the measuring roll body at a distance from the circumferential surface of the measuring roll body, there is the problem that the radially acting forces are scattered by the material of the measuring roll body through which they must pass to reach the sensor surface of the force sensor. This phenomenon is called stress cone or "Roetscherkegel". This effect leads to an arrangement of several force sensors that are widely spaced apart from one another in one recess. In this way, it is possible to avoid that two force sensors arranged next to one another deliver a measurement signal that is generated by only one radial force acting on one point on the circumferential surface of the measuring roll body in the course of the flatness measurement, which in practice has to be measured by only one of the two sensors for some evaluation methods of the prior art.

[0012] According to the invention, it is now possible to provide a method for measuring the flatness of a strip-shaped article, in particular a metal strip, as well as for detecting other properties of a strip-shaped article guided through a measuring roll, in which a first force sensor in the recess is arranged adjacent to the second force sensor so close that the sensor surface of the first force sensor is directly adjacent to the sensor surface of the second force sensor, or an end boundary line extending in the radial direction of the measuring roll and intersecting with a point of the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor, extends in a plane that includes a line connecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and a point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and It has been recognised that an advantage can be achieved if the angle between the line intersecting the point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor is close to being less than 65° and is positioned adjacent to the second force sensor.

[0013] The characteristic to be detected of the strip-like article guided through the measuring roll can be the position of this article relative to the measuring roll or, more specifically, the position of the edge of the strip-like article on the measuring roll ("strip edge position"). It was recognized that if the first force sensor is arranged adjacent to the second force sensor, at least for the section along the longitudinal axis of the measuring roll in which both force sensors are located, monitoring of the strip edge position can be performed, for example, whether the strip is still present above the first force sensor while above the second force sensor the strip is no longer wound around the measuring roll. According to the invention, for example, both force sensors (or preferably further force sensors) can be arranged together in one recess in a predefined section of the measuring roll body, i.e. in a section in which the position of the strip edge is expected based on the manufacturing process. This allows the two force sensors (or preferably several force sensors arranged there) to accurately detect the position of the strip edge in this section. Alternatively, according to the invention, both force sensors (or preferably further force sensors) can be arranged in recesses arranged close to each other in a defined section of the measuring roll body, i.e. in a section where the position of the strip edge is expected based on the manufacturing process, so that both force sensors (or preferably several force sensors arranged there) can accurately detect the position of the strip edge in this section. The characteristic to be detected can also be the strip width. If the position of the strip edge is known, the strip width can also be calculated from this.

[0014] The characteristic to be detected of the strip-shaped article guided through the measuring roll can be the flatness of the strip. By means of the individual measured values ​​of the force sensors, the local radial forces generated by the strip being moved through the roll body are measured. From the radial forces, the strip tensile stress distribution or the strip flatness or a reference value ("I-Unit") which is representative of the strip flatness is calculated.

[0015] Furthermore, in the case of a preferred embodiment in which the recess extends over the entire width of the measuring roll body in the longitudinal direction of the measuring roll body, in which the strip-shaped article to be inspected is expected to be placed, the entire recess thus configured is filled with a plurality of force sensors, each of which has a sensor surface and which is capable of generating a sensor signal in each case in case of a change in the position of the sensor surface, the force sensors being arranged such that the sensor surface of one force sensor is directly adjacent to the sensor surface of the force sensor adjacent to it, or each force sensor has an end boundary line extending in the radial direction of the measuring roll and intersecting with a point of the sensor surface of the respective force sensor which is closest to the sensor surface of the force sensor adjacent to the respective force sensor, extend in a plane that includes a line connecting a point on the sensor surface of each force sensor that is closest to the sensor surface of the adjacent force sensor and a point on the sensor surface of the adjacent force sensor that is closest to the sensor surface of each force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and The angle between the line intersecting the point of the sensor surface of the force sensor adjacent to the respective force sensor, which is closest to the sensor surface of the respective force sensor, is less than 65° so that the strap tension can be determined when the strip-shaped article is pulled through the measuring roll. The strap tension is proportional to the sum of the radial forces acting on the peripheral surface sections of the measuring roll body arranged adjacent to each other, which are applied to the peripheral surface via the strip-shaped article guided through the measuring roll. If the sum of these forces can be determined according to the above-mentioned embodiment, the strap tension can be determined. This provides the advantage that in a higher-level device in which the measuring roll according to the invention can be integrated, a further measuring device for detecting the strap tension can be omitted. The strap tension is a necessary calculation criterion in some calculation methods when determining the flatness of the strip from the sensor signals of the force sensors. Therefore, for the pure measurement of the flatness of the strip-like article, the possibility of determining the strip tension provides the advantage that, by means of the same measuring roll, the calculation criterion (strip tension) required for the further evaluation of the sensor signal for detecting the flatness of the strip-like article can be determined according to several calculation methods.

[0016] Furthermore, in a preferred embodiment in which each force sensor is arranged in its own recess and these recesses with the force sensors are distributed in the longitudinal direction of the measuring roll body over the entire width of the measuring roll body, in which the strip-shaped article to be inspected is expected to be placed, force sensors each having one sensor surface can generate a sensor signal in the event of a change in the position of the sensor surface, the force sensors being arranged such that the sensor surface of a force sensor is directly adjacent to the sensor surface of the force sensor adjacent to it, or each force sensor has an end boundary line extending in the radial direction of the measuring roll and intersecting with a point of the sensor surface of the respective force sensor that is closest to the sensor surface of the force sensor adjacent to the respective force sensor, extend in a plane that includes a line connecting a point on the sensor surface of each force sensor that is closest to the sensor surface of the adjacent force sensor and a point on the sensor surface of the adjacent force sensor that is closest to the sensor surface of each force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and - The force sensors are arranged adjacent to their respective force sensors such that the angle between the line intersecting the point on the sensor surface of the force sensor adjacent to the respective force sensor closest to the sensor surface of the respective force sensor is less than 65°, and the belt tension can be determined when a belt-shaped article is pulled through the measuring roll.

[0017] The arrangement of the force sensors at close or nearly close intervals makes it possible to simultaneously measure the forces applied to the outer surface of the measuring roll across the roll width. By summing the individual measured values ​​of the force sensors, it is possible to determine the strap tension with which the strap is applied to the roll surface, taking into account the strap deflection angle. For example, the individual measured values ​​F R,i From the sum of F R,ges From N

number

number

[0018] According to a preferred embodiment, if the measuring roll is equipped with a temperature sensor, this embodiment of the measuring roll makes it possible to determine the flatness of the strip-shaped article as well as the strip tension and the temperature. With such a measuring roll, it is possible to dispense with measuring devices for measuring the strip tension or measuring devices for measuring the temperature, which in the prior art were previously arranged separately, and to measure all three parameters with one measuring device, i.e. with the method according to the invention.

[0019] Over the width of the measuring roll, the temperature profile inside the recess wall is approximately proportional to the temperature profile prevailing at the roll surface. The roll surface temperature is also approximately proportional to the temperature profile in the strip. Thus, the temperature profile in the strip can be determined over the strip width by the measuring roll via a number of temperature sensors distributed over the measuring roll width on the measuring roll.

[0020] Furthermore, the measuring roll according to the invention allows the band speed to be measured, the rotational speed of which is proportional to the speed at which the band, partially wound around the measuring roll, is guided through the measuring roll. The band speed can therefore be determined by a rotation sensor which measures the rotational speed of the measuring roll. An incremental encoder attached to the roll body allows the circumferential speed of the measuring roll and, from this, the band speed of the band moved through the roll body to be calculated.

[0021] In a preferred embodiment, the evaluation device generates information that corresponds to the strap tension or is directly proportional to the strap tension when the web-shaped article is guided through the measuring roll as a function of the sensor signal of the first force sensor and the sensor signal of the second force sensor. The sensor signals of the first force sensor and the sensor signal of the second force sensor are electrical signals whose intensity depends on the magnitude of the change in position of the sensor surface relative to the reference position. The magnitude of the change in position of the sensor surface relative to the reference position depends on the magnitude of the force acting radially on the circumferential surface of the measuring roll body from above the respective sensor surface. Thus, by means of a calibration factor that can be easily determined, for example by testing, the evaluation unit can convert the electrical signal of the respective force sensor into a value that corresponds to the magnitude of the force, measured, for example, in Newtons, acting radially on the circumferential surface of the measuring roll body from above the respective sensor surface. The sum of the individual forces thus determined, i.e. the sum of the sensor signals of the force sensors, correspondingly converted by the evaluation unit using the calibration factor, gives the strap tension or a value that is directly proportional to the strap tension. It is conceivable that the value determined by the sum of the sensor signals of the force sensors, correspondingly converted by means of the calibration factor, must be converted to the strap tension by means of another calibration factor, which can be determined by simple testing. However, the force sensors are not arranged so that the sensor surface of the first force sensor is directly adjacent to the sensor surface of the second force sensor, but are arranged so that the sensor surface of the first force sensor is adjacent to the sensor surface of the second force sensor, and the sensor surface of the second force sensor is adjacent to the sensor surface of the first force sensor. extends in a plane that includes a line connecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and a point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and In a preferred embodiment, where the angle between the line intersecting the sensor surface of the second force sensor closest to the sensor surface of the first force sensor is less than 65°, a gap is left between the sensor surfaces, in which case the value determined by a simple sum of the sensor signals of the force sensors, correspondingly converted by the evaluation unit using the calibration coefficients, can be smaller than the strap tension, since there is a lack of participation of the forces acting on the circumferential surface of the measuring roll body from above the gap left between the sensor surfaces. However, this lack of participation can be generally compensated for by a calibration coefficient, which can be determined by simple testing.

[0022] In a preferred embodiment, the strip-shaped article guided through the measuring roll covers an area of ​​the circumferential surface of the measuring roll and guides a recess through this area at least once per revolution of the measuring roll, the recess extending parallel to the longitudinal axis of the measuring roll body and having a chain of force sensors at least over the width of this area oriented parallel to the longitudinal axis, in which each force sensor, except for the last force sensor at each end of the chain, is arranged such that the sensor surface of the respective force sensor is directly adjacent to the sensor surface of the force sensor adjacent to this respective force sensor in the direction of the chain and directly adjacent to the sensor surface of the force sensor adjacent to this respective force sensor in the opposite direction of the chain, or each force sensor has an end boundary line extending in the radial direction of the measuring roll and intersecting with a point of the sensor surface of the respective force sensor that is closest to the sensor surface of the force sensor adjacent to the respective force sensor, extend in a plane that includes a line connecting a point on the sensor surface of each force sensor that is closest to the sensor surface of the adjacent force sensor and a point on the sensor surface of the adjacent force sensor that is closest to the sensor surface of each force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and Each force sensor is disposed adjacent to a force sensor adjacent to the respective force sensor in the direction of the chain such that an angle between the line intersecting the point on the sensor surface of the force sensor adjacent to the respective force sensor closest to the sensor surface of the respective force sensor is less than 65°; and each force sensor has an end boundary line extending in a radial direction of the measuring roll and intersecting a point on the sensor surface of the respective force sensor that is closest to the sensor surface of the force sensor adjacent to the respective force sensor; extend in a plane that includes a line connecting a point on the sensor surface of each force sensor that is closest to the sensor surface of the adjacent force sensor and a point on the sensor surface of the adjacent force sensor that is closest to the sensor surface of each force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and - The force sensors are arranged adjacent to the force sensors adjacent to their respective force sensors in the opposite chain direction such that the angle between the line intersecting the point on the sensor surface of the force sensor adjacent to the respective force sensor closest to the sensor surface of the respective force sensor is less than 65°.

[0023] In a preferred embodiment, the strip-like article guided through the measuring roll covers an area of ​​the circumferential surface of the measuring roll and guides a chain of recesses through this area at least once per revolution of the measuring roll, the recesses being arranged parallel to the longitudinal axis of the measuring roll body and at least over the width of this area oriented parallel to the longitudinal axis, one force sensor being arranged in each recess of the chain, each force sensor, except for the last force sensor at each end of the chain, having an end boundary line extending in the radial direction of the measuring roll and intersecting with a point of the sensor surface of the respective force sensor that is closest to the sensor surface of the force sensor adjacent to the respective force sensor, extend in a plane that includes a line connecting a point on the sensor surface of each force sensor that is closest to the sensor surface of the adjacent force sensor and a point on the sensor surface of the adjacent force sensor that is closest to the sensor surface of each force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and Each force sensor is disposed adjacent to a force sensor adjacent to the respective force sensor in the direction of the chain such that an angle between the line intersecting the point on the sensor surface of the force sensor adjacent to the respective force sensor closest to the sensor surface of the respective force sensor is less than 65°; and each force sensor has an end boundary line extending in a radial direction of the measuring roll and intersecting a point on the sensor surface of the respective force sensor that is closest to the sensor surface of the force sensor adjacent to the respective force sensor; extend in a plane that includes a line connecting a point on the sensor surface of each force sensor that is closest to the sensor surface of the adjacent force sensor and a point on the sensor surface of the adjacent force sensor that is closest to the sensor surface of each force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and - The force sensors are arranged adjacent to the force sensors adjacent to their respective force sensors in the opposite chain direction such that the angle between the line intersecting the point on the sensor surface of the force sensor adjacent to the respective force sensor closest to the sensor surface of the respective force sensor is less than 65°.

[0024] In a preferred embodiment, information is obtained as to which force sensors, viewed in the radial direction of the measuring roll body, are located below the area covered by the strip-shaped article guided through the measuring roll. An embodiment is conceivable in which the individual force sensors are provided with a reference, preferably a number, and by reproducing the corresponding reference, information is obtained, for example, which force sensors are covered by the strip. It is also conceivable to obtain, for example, which force sensors are not covered by the strip by reproducing the corresponding reference. It is also conceivable that the information conveys only the reference of the last covered force sensor, or, for example, the reference of the first force sensor that is no longer covered. Furthermore, an embodiment is also possible in which the position of the individual force sensors relative to a reference point of the measuring roll, for example the edge of the measuring roll or, for example, the center of the measuring roll, is stored in the evaluation unit. This allows the evaluation unit to express the strip edge position with respect to this reference point. If the last force sensor that is still covered by the strip is, for example, 250 mm away from the center of the measuring roll, the evaluation unit can emit the information that the strip edge is located 250 mm away from the center of the measuring roll.

[0025] In a preferred embodiment, the measuring roll has a temperature sensor, and the evaluation unit outputs, in addition to the information generated by the evaluation unit, the temperature measured by the temperature sensor or a value that depends on the temperature measured by the temperature sensor.

[0026] In a preferred embodiment, the evaluation device generates further information that depends on the flatness of the web-shaped article guided through the measuring roll depending on the sensor signal of the first force sensor and on the sensor signal of the second force sensor.

[0027] The measuring roll has a measuring roll body. The measuring roll body preferably has a closed circumferential surface. In a preferred embodiment, the measuring roll body is a solid roll extending along the longitudinal axis. A solid roll means a measuring roll body which is integral and whose shape is produced by a one-piece forming process, for example by casting, and / or whose geometric shape is produced from an integral semi-finished product by a separate process, in particular by machining, in particular by turning, drilling, milling or grinding. In a preferred embodiment, in such a measuring roll body formed as a solid roll, the measuring roll journals arranged on the respective end faces of the measuring roll are also part of the integral body, for example for the purpose of rotatably supporting the measuring roll in ball bearings. However, configurations are also conceivable, such as for example shown in FIG. 2 of DE 202014006820, in which the main part of the measuring roll body is formed as a cylindrical solid roll, which has a cover arranged on the end face, on which the measuring roll journals are formed. Furthermore, the measuring roll body according to the invention can be formed, for example, like the measuring roll body illustrated in FIG. 3 of DE 202014006820, in which case an integral journal is formed on the measuring roll body and a cover tube is placed on the measuring roll body. In a particularly preferred embodiment, however, the measuring roll does not have a cover tube and is formed as a solid roll. Also conceivable is an embodiment in which the measuring roll body according to the invention is formed from separate plates arranged next to one another, as shown, for example, in DE 2630410.

[0028] The measuring roll body of the measuring roll according to the invention preferably has a closed circumferential surface. A closed circumferential surface can be obtained, for example, by forming the measuring roll body as a solid roll and forming all recesses provided in the measuring roll body in such a way that none of the recesses leads from the recesses to the circumferential surface. In such an embodiment, the recesses are particularly preferably guided in the axial direction and have an opening at the end face of the measuring roll body or a transverse passage is provided inside the measuring roll body, which leads from the recesses in the radial direction further into the interior of the measuring roll body, for example to a collecting passage in the center of the measuring roll body. A closed circumferential surface of the measuring roll body can also be obtained in an embodiment in which the respective recesses have recesses leading in the direction towards the circumferential surface, in that these recesses are closed by a closing element. Such a closing element can be, for example, a cover tube, as shown in figures 3 and 4 of DE 10 2014 012 426 A1, which completely surrounds the base body of the measuring roll body. However, the closing element can also be formed in the form of a cover as shown in DE 197 47 655 A1. In a preferred embodiment, however, the measuring roll does not have a cover tube, but is formed as a solid roll, with none of the recesses leading from the recesses to the periphery, or each recess leading in the direction towards the periphery, but closed by a closing element, for example a cover. It is also conceivable to cover the periphery of the solid roll or the periphery of the cover tube, for example for the purpose of reducing friction or for the purpose of protecting the web-shaped article to be guided through the measuring roll.

[0029] The measuring roll body of the measuring roll according to the invention is provided with at least one recess. It has been shown that the advantages of the invention can already be obtained with a single recess provided in the measuring roll body. If the measuring roll according to the invention is used, for example, to determine the strip tension, it may be sufficient if such information is provided once per revolution of the measuring roll. The measuring roll according to the invention can therefore already be used successfully with only one recess. Similarly, in the case of flatness measurements, it is conceivable to provide information about the flatness of a strip-shaped article guided through the measuring roll once per revolution of the measuring roll.

[0030] In a preferred embodiment, the measuring roll body has a number of recesses. In a preferred embodiment, the recesses are formed with the same radial spacing relative to the longitudinal axis of the measuring roll body. In a preferred embodiment, all recesses are distributed equidistantly from one another in the circumferential direction. However, particularly preferred is an embodiment in which a first group of recesses is provided which is distributed equidistantly in the circumferential direction with the same radial spacing relative to the longitudinal axis, and in addition to the first group of recesses, at least one further recess is provided, which is formed such that its radial spacing relative to the longitudinal axis is different from that of the first group of recesses and / or does not have the same spacing in the circumferential direction relative to the other recesses as the other recesses have relative to one another. Thus, for example, for flatness measurements, it is conceivable to configure the measuring roll like a prior art measuring roll, for example as a solid roll known from DE 10207501 A1 or as a measuring roll known from DE 102014012426 A1, but in this case, for the configuration according to the invention, such prior art measuring rolls can be provided with further recesses configured outside the pattern, in which further measurements, for example strip tension measurements, are performed. Preferably, the recesses mentioned in this paragraph are recesses extending in the axial direction of the measuring roll body. Also conceivable is an embodiment in which the measuring roll has only one recess and all force sensors of the measuring roll are arranged in only one recess, for example in only one axially extending recess.

[0031] In a preferred embodiment, the measuring roll body has a closed circumferential surface and is closed at the end sides by end faces, which in a preferred embodiment are arranged at an angle of approximately 90° to the circumferential surface.

[0032] In a preferred embodiment, the measuring roll has a bearing journal, which in a preferred embodiment is formed at the end face in an embodiment of the measuring roll having an end face.

[0033] In a preferred embodiment, the measuring roll body is cylindrically shaped.

[0034] In a first aspect of the invention, the measuring roll according to the invention is formed with at least one recess in the measuring roll body, which recess is arranged at a distance from the circumferential surface, and which recess is not open towards the circumferential surface or further recesses, e.g. holes, leading from the recess to the circumferential surface. In a second aspect of the invention, the recess leads from the circumferential surface into the interior of the measuring roll body, but is closed by a closing element. In a preferred embodiment, the measuring roll is formed with a plurality of recesses in the measuring roll body, which recesses are arranged at a distance from the circumferential surface, and all recesses are formed such that the recesses, e.g. holes, do not lead from the recess to the circumferential surface (and the recesses themselves do not open to the circumferential surface), or some recesses are formed such that no recess leads from the respective recess to the circumferential surface, and in other recesses there are recesses leading in the direction towards the circumferential surface, but these recesses are closed by a closing element. The closing element is, as mentioned above, a cover or, for example, a cover tube.

[0035] In a preferred embodiment, one recess of the measuring roll body extends in a direction parallel to the longitudinal axis of the measuring roll body. According to a preferred embodiment, if the measuring roll body is provided with several recesses, then preferably all recesses of the measuring roll body each extend in a direction parallel to the longitudinal axis of the measuring roll body. In a preferred embodiment, each recess is open at least at one end, preferably at both ends, at the end face of the measuring roll body. The recess terminating at one end face of the measuring roll body can be closed by an end cap, which closes only this recess. Also conceivable is an embodiment in which the end face of the measuring roll body is entirely closed by a cover, as shown, for example, in FIG. 1 and FIG. 2 or FIG. 4 of DE 10 2014 012 426 A1.

[0036] In a preferred embodiment, the recess is elongated, where "elongated" means that the recess is larger in a first direction (longitudinal direction of the recess) than in a direction extending approximately perpendicular to this direction. In a preferred embodiment, the extension in the longitudinal direction of the elongated recess is twice as large, or more preferably more than twice as large, as compared to a direction extending approximately perpendicular to this direction. In a preferred embodiment, the longitudinal direction of the recess forms an angle with the longitudinal direction of the measuring roll body of less than 75°, particularly preferably less than 45°, particularly preferably less than 30°, particularly preferably less than 10°, particularly preferably less than 5°. In a preferred embodiment, the longitudinal direction of the recess does not extend perpendicular to the longitudinal axis of the measuring roll body. If, as is conceivable in one embodiment, the longitudinal axis of the recess does not intersect with the longitudinal axis of the measuring roll body, the design provisions as described above apply to the projection of the longitudinal axis of the recess onto a plane containing the longitudinal axis of the measuring roll body. In such an embodiment, the projection of the longitudinal axis of the recess into a plane containing the longitudinal axis of the measuring roll body is therefore formed in such a way that the longitudinal projection of the recess forms an angle of less than 75°, particularly preferably less than 45°, particularly preferably less than 30°, particularly preferably less than 10°, particularly preferably less than 5° with the longitudinal direction of the measuring roll body. In a preferred embodiment in which the recess extends parallel to the longitudinal axis of the measuring roll body, the longitudinal axis of the recess clearly does not intersect with the longitudinal axis of the measuring roll body, and likewise the projection of the longitudinal axis into a plane containing the longitudinal axis of the measuring roll body hardly intersects with the longitudinal axis of the measuring roll body. German Utility Model No. 202007001066 shows, for example, a measuring roll with an elongated recess.

[0037] In another preferred embodiment, the recesses are not elongated but are formed as radially extending pockets, as for example in DE 198 38 457 A1. In such an embodiment, the radially extending recesses can be dimensioned in their cross section such that they can accommodate two force sensors if, for example, they have the shape of the number 8. Alternatively, in this embodiment, one force sensor can be provided per recess, but in this case the recesses have an end boundary line extending in the radial direction of the measuring roll and intersecting with a point of the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor, and extends in a plane that includes a line connecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and a point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and The force sensors are arranged adjacent to each other so that the angle between the line intersecting the point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor is less than 65°.

[0038] In a preferred embodiment, a first and a second force sensor are arranged in one recess of the measuring roll (in the case where the measuring roll only has one recess). The first force sensor has a sensor surface, which can generate a sensor signal if the position of the sensor surface of the first force sensor changes. The second force sensor also has a sensor surface, which can generate a sensor signal if the position of the sensor surface of the second force sensor changes. The force sensor is called a force sensor because it is used to measure forces, particularly preferably pressing forces. To measure the forces acting on the force sensor, the force sensor has a sensor surface and is designed in such a way that it can generate a sensor signal if the position of the sensor surface changes. The force sensor often has an associated reference system and reacts to a change in the position of the sensor surface in this reference system. The force sensor often has a casing. In this case, the reference system is often the casing. The force sensor can detect in such an embodiment, for example, whether the position of the sensor surface has changed relative to the casing. If the force sensor is formed as a piezoelectric force sensor, for example, it has a piezoelectric quartz, which can generate an electrical signal when the position of the surface of the piezoelectric quartz changes relative to a reference surface, for example relative to the opposing surface of the piezoelectric quartz, for example when the piezoelectric quartz is compressed. In a force sensor formed as a strain gauge, the change in position of the surface of the force sensor changes the length of the measuring wire or of the measuring grid formed from the measuring wire, which is mainly stretched, but also partially crushed. In a force sensor formed as an optical force sensor, the optical properties of the force sensor, for example the refractive index or reflection properties, change with the change in position of the surface.

[0039] The force sensor mounted according to the invention has a sensor surface, the positional changes of which are monitored in order to determine the force acting on the force sensor. An embodiment is conceivable in which the sensor surface is the surface of an element whose properties change in order to generate a sensor signal, for example the surface of the piezoelectric quartz itself. However, in many cases, in force sensors of this type, an intermediate element is provided on which the sensor surface is formed. In many cases, intermediate elements of this type are rigid blocks, in which a change in the position of one surface of the rigid block directly leads to a change in the position of the opposite surface due to the rigidity of the block. Intermediate elements of this type can be used to form the sensor surface protruding from the rest of the force sensor, in particular from the casing. A sensor surface protruding from the rest of the force sensor forms a clearly defined surface on which the environment can act, which increases the measurement accuracy. A protruding sensor surface can, for example, avoid measurement errors due to branching of forces. The force sensor according to the invention can be configured, for example, like the force sensor shown in DE 1 773 551 A1 and can have a piezoelectric element consisting of a multi-layer crystal assembly arranged between two force transmission plates arranged in a casing. In such an embodiment, the sensor surface is the outer surface of the upper force transmission plate in FIG. 1 of DE 1 773 551 A1 or the outer surface of the lower force transmission plate in FIG. 1 of DE 1 773 551 A1.

[0040] In a preferred embodiment, the sensor surface is flat. In a preferred embodiment, the surface normal of the flat sensor surface of the first force sensor is directed towards the circumferential surface. The surface normal of the sensor surface of the second force sensor is likewise flat and likewise directed towards the circumferential surface in a preferred embodiment. In a preferred embodiment, the surface normal of the sensor surface of the first force sensor is parallel to the surface normal of the sensor surface of the second force sensor. In a preferred embodiment, the radial direction of the measuring roll body is the surface normal of the sensor surface of the first force sensor and / or the second force sensor.

[0041] In a preferred embodiment, the surface normal of the flat sensor surface, at the point of the sensor surface where the sensor surface intersects with a radial line of the measuring roll body, forms an angle of less than 45°, particularly preferably less than 20°, particularly preferably less than 10°, particularly preferably less than 5° with respect to this radial line of the measuring roll body.

[0042] In a preferred embodiment, the sensor surface of the force sensors, in particular of the first force sensor and / or the second force sensor, used in the measuring roll according to the invention is a flat surface.

[0043] In a preferred embodiment, the sensor surface of the first force sensor is formed symmetrically with respect to a plane which includes the longitudinal axis of the measuring roll body, intersects the sensor surface of the force sensor and in which the surface normal of the sensor surface also lies.

[0044] In a preferred embodiment, the sensor surface is ring-shaped, in particular annular. Also preferred are embodiments in which the sensor surface is circular or elliptical. Rectangular, square or polygonal sensor surfaces are also conceivable. In a preferred embodiment, the sensor surface is flat.

[0045] In a preferred embodiment, the sensor surface is a surface that protrudes from the other elements of the force sensor and is in contact with a boundary surface of the recess or with a closing surface that closes the recess against the surrounding surface.

[0046] In a preferred embodiment, at least two force sensors used in the measuring roll according to the invention, particularly preferably some of the force sensors used in the measuring roll according to the invention, particularly preferably all force sensors used in the measuring roll according to the invention, are configured similarly and therefore in the same way, in particular of the same type, particularly preferably identically.

[0047] According to a first variant of the measuring roll according to the invention, the first force sensor is arranged in the recess adjacent to the second force sensor. This means that the sensor surface of the first force sensor is arranged closer to the end face of the measuring roll body than the sensor surface of the second force sensor. It is conceivable that the first force sensor is arranged in the recess offset in the circumferential direction with respect to the second force sensor. However, in a preferred embodiment, the first and second force sensors are arranged without being offset from each other in the circumferential direction.

[0048] In a preferred embodiment, the first force sensor and the second force sensor are arranged at the same radial distance relative to the longitudinal axis of the measuring roll body.

[0049] In the measuring roll according to the invention, the sensor surface of the first force sensor is directly adjacent to the sensor surface of the second force sensor, or the first force sensor extends in the radial direction of the measuring roll and has an end boundary line that intersects with a point of the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor; extends in a plane that includes a line connecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and a point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and The first force sensor is located adjacent to the second force sensor such that the angle between the line intersecting the point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor is less than 65°.

[0050] Of the two alternative embodiments according to the invention described above, the embodiment in which the sensor surface of the first force sensor is directly adjacent to the sensor surface of the second force sensor is particularly preferred. Thus, for example, in the case of a circular or toric sensor surface, a point located on the circumference of the first circularly or toric sensor surface is adjacent to a point located on the circumference of the second circularly or toric sensor surface. In such an embodiment of the invention, the radial forces acting on the circumference of the measuring roll can be completely measured. However, such an arrangement leads to a branching of forces, and it is expected that the movement of the first sensor surface due to the forces acting on it will cause the second sensor surface to move, for example, due to friction at the periphery of the sensor surface. Branching of forces can only be prevented if the periphery of the sensor surface is so smoothly designed that it does not transmit frictional forces. In the practically relevant implementation, therefore, it is mainly assumed that the sensor surfaces are spaced slightly apart from one another, so that the measurement result of each sensor surface is not influenced by the load of the adjacent sensor surface.

[0051] In another alternative embodiment according to the invention, the sensor faces are spaced apart from one another, but extend in the radial direction of the measuring roll and intersect with a point on the sensor face of the first force sensor that is closest to the sensor face of the second force sensor, and extends in a plane that includes a line connecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and a point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and The force sensors are positioned close enough to each other that the angle between the line intersecting the point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor is less than 65°.

[0052] The claimed design rule according to the invention presupposes an end boundary line extending in the radial direction. In practical use, measuring rolls are usually used for measuring radially acting forces. Such forces occur when the strip-shaped article to be tested is partially wound around the measuring roll. The end boundary line defines the point at which the radially acting force is still directly located above the sensor surface of one of the force sensors by the point at which the end boundary line crosses the circumferential surface, but only above the points located around the sensor surface, whether the sensor surface is circularly or annularly formed.

[0053] Given such edge boundaries, the present invention defines the spacing for adjacent sensor faces as: extends in a plane that includes a line connecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and a point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and Defined via the angular position of a line intersecting a point on the sensor surface of the second force sensor which is closest to the sensor surface of the first force sensor.

[0054] According to the invention, the angle between these lines is less than 65°, particularly preferably less than 55°, particularly preferably equal to or less than 45°, particularly preferably equal to or less than 40°, particularly preferably equal to or less than 35°, particularly preferably equal to or less than 30°, particularly preferably equal to or less than 20°, particularly preferably equal to or less than 10°, particularly preferably equal to or less than 5°.

[0055] Therefore, according to the invention, an embodiment is also provided in which a portion of the second sensor surface is inside a "Roetscherkegel" originating from a radially acting force acting on the circumferential surface at the intersection of the end boundary line and the circumferential surface.

[0056] In a preferred embodiment, the line connecting the point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and the point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor runs parallel to the longitudinal axis of the measuring roll. This is in particular the case when the first and the second force sensor are arranged in an elongated recess, the direction of longitudinal extension of which runs parallel to the longitudinal axis of the measuring roll. However, embodiments are also conceivable in which the first force sensor is arranged in a first radial recess, preferably in a pocket, and the second force sensor is arranged in a second radial recess, preferably in a pocket. In such an embodiment, the line connecting the point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and the point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor likewise runs parallel to the longitudinal axis of the measuring roll. However, embodiments are also conceivable in which the radial recess of the first force sensor is arranged axially (radially relative to the longitudinal axis of the measuring roll) and in the circumferential direction of the measuring roll offset relative to the radial recess of the second force sensor. In such embodiments, the line connecting the point of the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and the point of the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor does not run parallel to the longitudinal axis of the measuring roll. Such an orientation of the line also occurs with elongated recesses, the longitudinal axis of which does not run parallel to the longitudinal axis of the measuring roll body, but has a circumferentially oriented component.

[0057] In a preferred embodiment, the line connecting the point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and the point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor extends at an angle to a plane extending perpendicular to the longitudinal axis of the measuring roll, preferably at an angle of more than 1 °, particularly preferably at an angle of more than 5 °, particularly preferably at an angle of more than 10 °, particularly preferably at an angle of more than 15 °, particularly preferably at an angle of more than 20 °, particularly preferably at an angle of more than 25 °, particularly preferably at an angle of more than 30 °, particularly preferably at an angle of more than 45 °. In a preferred embodiment, this angle is less than or equal to 90 °. If this angle is 90° according to a particularly preferred embodiment, the line connecting the point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and the point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor runs parallel to the longitudinal axis of the measuring roll. In a preferred embodiment, the point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and the point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor are not located one behind the other in the circumferential direction.

[0058] The understanding according to the invention can be expressed in terms of the web height for the embodiment in which the sensor surface is in contact with the recess boundary surface located closest to the circumferential surface of the measuring roll body, where web means the material between the circumferential surface of the measuring roll body and the recess boundary surface located closest to the circumferential surface of the measuring roll body. The web height can be 2 mm or more, preferably 5 mm or more, and is preferably 20 mm or less, preferably 15 mm or less, particularly preferably 12 mm or less. In an alternative way of expressing the understanding according to the invention, the point of the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor is separated from the point of the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor by less than 2.2 times the web height, preferably less than 2 times the web height, particularly preferably less than 1 time.

[0059] In a preferred embodiment, the first and second force sensors are arranged in a recess that runs from one end face of the measuring roll body to the opposite end face of the measuring roll body. In an alternative configuration, the recess in which the first and second force sensors are arranged runs parallel to the longitudinal axis of the measuring roll body and extends over at least 50%, particularly preferably over at least 60%, particularly preferably over at least 75%, particularly preferably over at least 80%, particularly preferably over at least 90%, particularly preferably over at least 95% of the length of the measuring roll body that would be obtained if the length of the measuring roll body were measured from end face to end face (i.e. without taking into account the journals).

[0060] In the embodiment in which the measuring roll has a number of recesses, all recesses are conceivable in a similar manner, i.e. in a longitudinal extension parallel to one another and in a similar length. In an alternative embodiment, the measuring roll with a number of recesses is conceivable in such a way that at least one recess is designed to meet the above-mentioned design rules, i.e. to extend over at least 50%, particularly preferably over at least 60%, particularly preferably over at least 75%, particularly preferably over at least 80%, particularly preferably over at least 90%, particularly preferably over at least 95% of the length of the measuring roll body obtained when the length of the measuring roll body is measured from end face to end face (i.e. without taking into account the journals), and the other recesses are conceivable in a shorter manner. Figure 5 of DE 10207501 shows the possibility of spirally grading the depth of the recesses. Such an embodiment can be supplemented with the following regarding the selection of the length of the recesses: the axially extending recesses shown here are designed to extend from one end face of the measuring roll to the opposite end face.

[0061] In a preferred embodiment, the recess has an opening arranged on one end side of the measuring roll body. This recess may be designed in an open state. However, a configuration in which the recess is closed by a cover is also conceivable. If several recesses are provided that are open on the end side, then in this embodiment each recess has its own cover. In particular in such an embodiment, an embodiment of the measuring roll according to the invention is also conceivable in which the measuring roll has several recesses, the measuring roll body having an end cover for jointly closing the openings of the recesses, for example as shown in FIG. 1 or FIG. 2 of DE 102014012426 A1. Likewise, in particular with regard to an embodiment in which the measuring roll has several recesses, it is conceivable for these recesses each to have an opening arranged on one end side of the measuring roll body, which openings are closed by an end cover, for example as shown in FIG. 1 of DE 10207501 A1.

[0062] In a preferred embodiment, the measuring roll has a number of force sensors which are all arranged in one recess, particularly preferably more than 5, particularly preferably more than 7, particularly preferably more than 10, particularly preferably more than 15 force sensors are arranged in one recess.

[0063] In a preferred embodiment, the measuring roll has a first recess in which a number of force sensors are arranged adjacent to one another, particularly preferably more than 5, particularly preferably more than 7, particularly preferably more than 10 and particularly preferably more than 15 force sensors are arranged in the first recess; in this embodiment the measuring roll has further recesses in which only one force sensor or less than 15, particularly preferably less than 10, particularly preferably less than 7 and particularly preferably less than 5 force sensors are arranged in each of the further recesses.

[0064] In a preferred embodiment of the measuring roll in which several force sensors are arranged in one recess, the force sensors are distributed equidistantly over the length of the recess, at least equidistantly from each other (for embodiments in which the distance of the last force sensor to the end of the recess does not correspond to the distance it has to its neighboring (penultimate) force sensor). However, embodiments are also conceivable in which the force sensors of the first group are arranged equidistantly from each other and the force sensors of the second group are arranged at different distances from the force sensors of the first group, in which case the force sensors of the second group can also be arranged equidistantly from each other. Thus, a predefined zone can be formed inside the recess, in which the force sensors are arranged closer to each other, and further force sensors arranged outside this zone are arranged more widely spaced from each other. Such an embodiment is particularly suitable if, when the position of the strip edge of a strip-shaped article is to be detected, it is already known in the design of the measuring roll in which area / zone the strip edge of the strip-shaped article is likely to be located. In this case, in this area, the density of force sensors provided can be increased, whereas in the region located outside this area of ​​the recess, the force sensors can be arranged more widely spaced apart from one another in a preferred embodiment.

[0065] The embodiment with several force sensors can also be replaced by the basic type according to the invention of the measuring roll, in which the force sensors are arranged in pockets, in which several, particularly preferably more than 5, particularly preferably more than 7, particularly preferably more than 10, particularly preferably more than 15 pockets are arranged adjacent to one another, in which each one of the force sensors arranged in each pocket has an end boundary line extending in the radial direction of the measuring roll and intersecting with a point of the sensor surface of the respective force sensor that is closest to the sensor surface of the respective force sensor adjacent to the respective force sensor, extend in a plane that includes a line connecting a point on the sensor surface of each force sensor that is closest to the sensor surface of the adjacent force sensor and a point on the sensor surface of the adjacent force sensor that is closest to the sensor surface of each force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and · near adjacent force sensors arranged in adjacent pockets to such an extent that the angle between the line intersecting the point of the sensor surface of the force sensor adjacent to the respective force sensor closest to the sensor surface of the respective force sensor is less than 65°. In a preferred embodiment, such design rule is met by all force sensors of this measuring roll. In an alternative embodiment, this design rule is met by some of the force sensors of the measuring roll, preferably by a plurality of force sensors, and further pockets are provided with internally arranged force sensors that do not meet this design rule. With regard to pockets with force sensors that meet the design rule, it is preferred if these pockets are arranged in one line, i.e. if the center points of the pockets are arranged on one line. This line preferably runs parallel to the longitudinal axis of the measuring roll body or in a spiral around the longitudinal axis of the measuring roll body. With respect to pockets with force sensors that meet the design rules, in an alternative embodiment, the pockets are offset from one another, so that each subsequent pocket is located in a line with the respective pocket, and the subsequent pockets are offset from each other, preferably in a line with the subsequent pocket of the respective pocket. Such an arrangement allows for a higher density of the pockets.

[0066] In a preferred configuration, the force sensor is wedged in the recess, whereby the force sensor can be loaded with a predefined preload in a particularly preferred embodiment. The force sensor is not only fixed in position at the position of the force sensor inside the recess by wedging, but can also be loaded with a preload force. Loading with a preload force is preferred, since when the measuring roll is used in normal operation, the installation conditions for the force sensor can change under different operating conditions, for example due to temperature changes. When the force sensor is installed in the recess, it is therefore preferred to load it with a preload force of such a height that the force connection between the force sensor and the recess wall remains intact under all operating influences during operation, in order to ensure a linear measurement without hysteresis.

[0067] In a preferred embodiment, the force sensor should be fixed in position in the recess, i.e. should be wedge-fixed, and should preferably be preloaded by means of the wedge fixation. In a preferred embodiment, the wedge fixation is formed in such a way that a preload is applied to the force sensor. This preload is particularly preferably selected in such a way that a force connection between the force sensor and the recess wall is maintained under all operating influences during operational use in order to ensure a linear measurement without hysteresis.

[0068] If different preloads occur during tightening, these can be easily compensated for by measurement technology. On the other hand, however, the preload can be intentionally adjusted in order to compensate for manufacturing tolerances of the force sensor and the recess. In this case, a force sensor with plane-parallel surfaces can be arranged between wedge-shaped holding elements, for example clamping wedges, which are moved relative to one another until the force sensor is immovably clamped between the holding elements.

[0069] One of the two retaining members is usually arranged in a fixed position in the recess where the force sensor is to be located, and the other retaining member is slid in until the force sensor is fixed in the recess, which can be achieved by a tension screw which is supported on the measuring roll body and which acts on the movable retaining member via a spacer sleeve.

[0070] An arrangement of multiple force sensors in a radially movable slide element which is fixed in the recess by means of a wedge strip is particularly preferred. The slide element can be arranged in a spacer strip and can be pressed radially outwardly by means of a wedge-shaped retaining projection of the clamping strip and clamped in the recess.

[0071] For a reliable attachment of the lines leading to the force sensor, the recesses can be connected to parallel running line passages. Alternatively, however, the recesses can also be connected via transverse passages to a central cable recess in the measuring roll. The transverse passages can run in the body of the measuring roll or can run as open passages at the end faces of the measuring roll, which can then be closed by covers.

[0072] To guide the retaining member or strip for the force sensor in the recess, the recess can be provided with longitudinal ribs which engage in complementary guide grooves in the body of the measuring roll.

[0073] In a preferred embodiment, the force sensor is held between two pairs of inner and outer wedge elements, which allows, on the one hand, the force sensor to be oriented in the direction of action of the pressing force to be measured, and, furthermore, such an arrangement allows the holder to be made geometrically symmetrical, possibly axially symmetrical, with respect to a plane that runs through the mounting position of the force sensor and is arranged perpendicular to the direction of action of the pressing force to be measured.

[0074] An advantage is already achieved by a holder for a force sensor which can measure a pressing force acting from above, which holder has the following components: a first inner wedge element arranged above an installation position provided for the force sensor, the first inner wedge element having an inner surface facing the installation position of the force sensor and an outer surface facing the inner surface and at an angle to the inner surface, a first outer wedge element facing the mounting position of the force sensor and having an inner surface that rests on the outer surface of the first inner wedge element and an outer surface facing said inner surface; a second inner wedge element arranged below the mounting position provided for the force sensor, the second inner wedge element having an inner surface facing the mounting position of the force sensor and an outer surface facing the inner surface and at an angle to the inner surface, a second outer wedge element, the second outer wedge element facing the mounting position of the force sensor and having an inner surface resting on the outer surface of the second inner wedge element and an outer surface facing said inner surface.

[0075] In this way, the wedge assembly required for the translational preloading of the holder and the force sensor in the recess is placed inside the holder. The outer surface of the holder can be adapted to the shape of the recess in which the holder and the force sensor are clamped, while the inner surface, which directly or indirectly influences the mounting direction of the force sensor, can be oriented as desired, for example perpendicular to the direction of action of the pressing force to be measured. Furthermore, it has been shown that with the holder according to the invention, the surface quality of the recess in which the holder is mounted (for example the axial recess) can be reduced without tilting. This eliminates the need for complex methods for producing a good surface quality, such as honing or spinning.

[0076] In a preferred embodiment, the holder is geometrically symmetrical with respect to a plane that runs through the mounting position of the force sensor and is arranged perpendicular to the direction of action of the pressing force to be measured. By adjusting the geometry of the components arranged above and below the force sensor, the tilting moment occurring in the event of preloading can already be reduced or even completely eliminated.

[0077] Alternatively or additionally, the holder can be designed symmetrically with respect to a plane extending through the mounting position of the force sensor and arranged perpendicular to the direction of action of the pressing force to be measured, with respect to the materials used for the components forming the holder and / or with respect to the surface qualities of these components. Tilting moments can arise not only due to geometric differences in the components provided above and below the force sensor, but also due to different friction forces arising between the surfaces moving against each other above and below the force sensor due to different material choices or different surface qualities. Such tilting moments can be prevented by designing the relevant materials or surface qualities symmetrically.

[0078] In a preferred embodiment, a connection is provided that connects the first and second inner wedge elements in order to prevent relative sliding in a direction other than the direction of action of the pressure to be measured. The tilting moment to be prevented can also result from the fact that the corresponding components on the upper side of the force sensor and on the lower side of the force sensor do not move synchronously with each other. This can be prevented by connecting the corresponding components to each other. However, such a connection is preferably formed in such a way that a sliding of the two connected components is possible in the direction of action of the pressure to be measured. In a holder for a force sensor for which a pressure acting from above is to be measured, it is preferable to keep the force branching as low as possible by constructional measures, i.e. to keep the portion of the pressure to be measured that is transmitted through the holder and past the force sensor small. This is achieved by forming the components spring-like relative to each other in the direction of action of the pressure to be measured and by making the spring stiffness of the force bridges caused by the connection as low as possible.

[0079] In a further embodiment of the invention, a connection is provided for connecting the first and second outer wedge elements in order to avoid relative sliding in a direction other than the direction of action of the pressing force to be measured, which offers similar advantages as when connecting the inner wedge elements.

[0080] Although the outer surface of the first inner wedge element and / or the outer surface of the second inner wedge element can be formed flat in the form of a flat wedge, in a preferred embodiment the outer surface of the first inner wedge element and / or the outer surface of the second inner wedge element are formed as part surfaces of a cone with a longitudinal axis running through the mounting position of the force sensor. With regard to the tilting moment occurring under preload, it is important to what degree the geometry of the facing surfaces of the individual surfaces moving relative to one another can be produced. It has been shown that the production of conical part surfaces, for example by turning or machining semi-finished products, can be produced more precisely than the flat surfaces of a flat wedge. This special configuration of the outer surfaces therefore allows the resulting tilting moment to be further reduced.

[0081] For the same reason, the inner surface of the first outer wedge element and / or the inner surface of the second outer wedge element is preferably formed as a partial surface of the boundary of a conical recess having a longitudinal axis extending through the mounting position of the force sensor.

[0082] In a preferred embodiment, the first and second inner wedge elements are partial elements of an inner sleeve that are manufactured in one piece, which provides advantages with regard to the manufacture of the components of the holder and with regard to the handling of the holder during the installation of the force sensor.

[0083] In a preferred embodiment, the inner sleeve has a longitudinal slit between the first and the second inner wedge element, which extends substantially perpendicular to the direction of action of the pressing force to be measured. This reduces the spring stiffness of the inner sleeve and therefore keeps the force branching small. Furthermore, the inner sleeve can be formed with a small wall thickness. A small wall thickness means, for example, a wall thickness of 0.3 mm to 5 mm for a normal inner diameter of, for example, 20 mm to 50 mm. The selected wall thickness of the sleeve can also be selected depending on the sleeve length, the sliding distance and the inclination. The wall thickness can be 1 / 10 mm at the thinnest point. In particular, the longitudinal slit can be formed in such a way that it has almost the entire longitudinal extension of the inner sleeve and leaves a thin web at one or both ends as a connection between the first and the second inner wedge element. In a preferred embodiment, the inner sleeve has two longitudinal slits. The longitudinal slits are preferably arranged in a plane which runs through the mounting position of the force sensor and which is arranged perpendicular to the direction of action of the pressing force to be measured.

[0084] As in the case of the inner wedge element, in a preferred embodiment, the first and second outer wedge elements can alternatively or additionally be partial elements or parts of an integrally manufactured outer sleeve, which in a preferred embodiment can likewise have at least one longitudinal slit between the first and second outer wedge elements, which extends substantially perpendicular to the direction of action of the pressing force to be measured.

[0085] In a preferred embodiment, the inner surface of the first inner wedge element and / or the inner surface of the second inner wedge element are flat and are arranged in a plane perpendicular to the direction of application of the pressing force to be measured, so that a force sensor, the upper and lower surfaces of which are mainly flat, can be slid between the two inner wedge elements in direct contact with the inner surfaces.

[0086] Alternatively, in a further embodiment of the invention, a first intermediate part with a spherical crown can be provided between the first inner wedge element and the mounting position of the force sensor and / or a second intermediate part with a spherical crown can be provided between the second inner wedge element and the mounting position of the force sensor, the spherical crown forming a surface facing one of the inner faces of the inner wedge element and configured to correspond to the associated inner face of the inner wedge element, the spherical crown preferably having the geometric shape of a partial face of the cylindrical body.

[0087] In a preferred embodiment of the invention, the outer surface of the first outer wedge element and / or the outer surface of the second outer wedge element are partial surfaces of a cylindrical body. Such an arrangement is particularly recommended in fields of use in which the force sensor is held in a recess by a holder, for example in an axial recess of a measuring roll.

[0088] The holder can have a centering pin which engages in a central recess in the component, allowing good and accurate positioning of individual loose components, such as force sensors, relative to other components, such as inner wedge elements or inner sleeves.

[0089] In a preferred embodiment, the holder has an internal thread in the first and second outer wedge elements and a compression screw screwed into the internal thread, the longitudinal axis of the internal thread extending through the mounting position of the force sensor, the compression screw being able to contact the first inner wedge element and the second inner wedge element and being able to slide relative to the first and second outer wedge elements. The compression screw allows a preload of the holder to be generated in a simple manner. Due to the angular configuration of the respective outer surfaces of the cooperating inner and outer wedge elements compared to the respective inner surfaces, the sliding of the wedge elements relative to each other displaces the outer wedge element away from the mounting position of the force sensor. In this way, the holder can be clamped in the recess.

[0090] Alternatively, the holder has an internal thread provided in the first and second inner wedge elements and a tension screw screwed into the internal thread, the longitudinal axis of the internal thread extending through the mounting position of the force sensor, and the screw head of the tension screw can contact the first outer wedge element and the second outer wedge element and can slide relative to the first and second inner wedge elements.

[0091] In a preferred embodiment, two or more force sensors are provided in the measuring roll to measure different mechanical forces. This allows the effects of temperature to be detected, which the inventors have realized can be sensed by measuring the mechanical forces present in the measuring roll and then calibrated accordingly. Thus, in addition to the other usual measurements of mechanical forces, a second mechanical force is measured, which can be due to the effect of heat input due to the use of the measuring roll on hot strip material. The measuring roll constructed according to the invention allows the proportion of the force caused by the heat input into the measuring roll body to be separated from the total signal of the force encoder.

[0092] The inventors have realized that according to a preferred embodiment, it is particularly preferred if one type of force sensor is a force sensor for measuring radial force, and one type of force sensor is a force sensor for measuring preload force of the force sensor for measuring radial force. Tests have shown that temperature changes on the surface of the measuring roll lead to elastic deformation of the measuring roll, so that the force sensor for measuring radial force, which is usually installed under preload force, changes its preload force and therefore also its linearity. A force sensor for measuring preload force of a different type from the first type applied to the force sensor for measuring radial force allows the influence of thermal deformation of the measuring roll body to be measured and the proportion of the measurement signal of the force for measuring radial force caused by thermal deformation to be separated from the radial force actually applied to the strip-like article.

[0093] The inventors further realized that if several force sensors are arranged in the longitudinal direction of the measuring roll, then a further type of force sensor measuring mechanical force can detect the relative temperature distribution over the width of the strip, in addition to the thermal deformations of the measuring roll, which affect the measurement result of the first type of force sensor. For example, for a heat input of 1° C., a value x of the unit N can be measured, which allows the temperature distribution to be determined in relation to the measured mechanical force.

[0094] Preferably, the force introduced by the strip being pulled in the longitudinal direction is measured dynamically by one type of force sensor, and the force resulting from the deformation of the measuring roll as a result of the thermal input is measured statically by the other type of force sensor, so that the radial forces measured by one type of force sensor can be corrected by the thermal input or the thermal deformation in relation to the respective actually measured forces.

[0095] In particular, a force sensor of one type can be fixed or clamped in the recess, for example by wedge clamping. This preload is predictable and can be easily compensated for by measurement technology. The preload can be adjusted by a predefined value. For example, a force sensor with plane-parallel surfaces can be arranged between wedge-shaped holding elements, for example clamping wedges, which are moved relative to one another until the force sensor is immovably clamped between the holding elements. Advantageously, a force sensor of another type can be fixed or clamped in the recess together with the force sensor of the first type in a housing. The force sensor of another type can be mounted, for example, in a recess formed in one of the holding elements, which clamps the force sensor of one type in the recess, or on one of the holding elements.

[0096] One of the two retaining members can be positioned stationary in the recess where the force sensor is to be located, and the other retaining member can be slid in to fix the force sensor in the recess, for example by means of a tension screw which is supported on the measuring roll body and acts on the movable retaining member via a spacer sleeve.

[0097] Particularly preferably, force sensors of various types are arranged adjacent to one another in order to measure the direct influence of the heat input "in situ" and to use the influence on the signal of another force sensor as a correction value.

[0098] In a preferred embodiment, one type of force sensor is arranged together with another type of force sensor in or on the surface of the casing or in or on the surface of the holder, which simplifies handling during production. The casing can be arranged in a recess of the measuring roll. For example, one type of force sensor can already be preloaded in the casing, in which case the other type of force sensor is arranged on the first type of force sensor and can measure the preload force. The first type of force sensor can be preloaded in and / or with the casing, in which case the other type of force sensor can determine the preload of the casing and thus the heat input. If both types of force sensors are arranged in the casing or on the casing surface, it is also ensured that both types of force sensors are arranged next to each other in order to accurately take into account the influences detected by one type of force sensor for the other type of force sensor.

[0099] The term "casing" according to the invention also includes holders that do not have the closed configuration of a normal casing. The casing according to the invention can be configured in particular as described in DE 10 2006 003 792 A1, the disclosure content of which is expressly incorporated herein by reference, the casing or holder having an inner sleeve with an outer peripheral cone on which a force sensor for measuring radial forces (one type of force sensor) is arranged and an outer sleeve with an inner peripheral cone that can engage with or be clamped to the inner sleeve. For example, a force sensor for measuring mechanical forces acting against radial forces (the other type of force sensor) can be arranged or attached in the inner sleeve or in a recess of the inner sleeve. For example, the force sensor can be glued. A force sensor for measuring mechanical forces acting against radial forces (the other type of force sensor) can also be arranged in the outer sleeve or in a recess of the outer sleeve. A force sensor for measuring the mechanical force acting against the radial force (the other type of force sensor) can also be arranged in the recess of the measuring roll in the area of ​​the place provided for the installation of the casing or holder, without being connected to the casing or holder itself.

[0100] In a preferred embodiment, the other type of force sensor is arranged to be in the flow of forces acting on the first type of force sensor, the arrangement being such that it should be in the flow of forces of one type of force sensor.

[0101] In a preferred embodiment, one type of force sensor is formed as a quartz force sensor, which is understood to be a piezoelectric element, on whose crystal surface the force to be measured generates an electric charge that is used as a measurement value. Such force sensors have small dimensions, high sensitivity, high natural frequency, stability and can compensate for preloads without impairing the measurement result.

[0102] Preferably, one type of force sensor is formed as a strain gauge, which can measure the preload force of a quartz force sensor, which can change when the measuring roll is deformed, for example as a result of heat input into the measuring roll.

[0103] In a preferred embodiment, the measuring roll comprises a temperature sensor, which in a preferred configuration is arranged inside the measuring roll body.

[0104] In an embodiment of the measuring roll according to the invention in which the hole leading from the recess in the direction of the periphery is closed by a closing element, it is particularly preferred if the temperature sensor is arranged in the closing element.

[0105] Arranging the temperature sensor in the measuring roll body has the advantage that the measurement value transmission unit (rotary transmission body) and the cable passage of the measurement line of the force encoder can be utilized for the measurement line and the voltage supply to the temperature sensor.

[0106] Thus, the distribution measurement of forces or stresses in the strip over space and time can be unified by a single temperature measurement, and thus the measurement errors caused by temperature differences across the strip can be directly corrected. Maintenance or cleaning of the temperature sensor, as is necessary in the case of optical systems, is eliminated.

[0107] In a preferred embodiment, one measuring roll therefore makes it possible to determine the flatness, the strip tension and the temperature of a strip of article guided through the measuring roll.

[0108] The temperature sensor can be provided in an integrated part in the recess, for example the temperature sensor can be arranged in a holder used to mount the force sensor in the recess, for example in a wedge element, however also embodiments are conceivable in which the temperature sensor is arranged in a specific recess, for example in a specific hole.

[0109] In a preferred embodiment, the temperature sensor is arranged radially closer to the circumferential surface of the measuring roll body than the sensor surface of the force sensor.

[0110] The measuring roll according to the invention is particularly suitable for use in determining properties of metal strips during their cold or hot rolling, in particular for determining the flatness of the strip. Further areas of application are, for example, in rerolling frames (skin pass frames), strip annealing lines, galvanizing lines, further processing lines such as stretching and straightening units.

[0111] The measuring roll according to the invention is particularly suitable for use in measuring the strip tension when the strip-shaped article is pulled through the measuring roll. Additionally or alternatively, the measuring roll can be used to detect the position of the strip-shaped article, represented by the position of the centerline of the strip-shaped article relative to a reference point, for example relative to the side of the measuring roll body or, for example, relative to the center of the measuring roll body, and / or to detect the position of the edge of the strip-shaped article on the circumferential surface of the measuring roll, represented by the position of the edge of the strip-shaped article relative to a reference point, for example relative to the side of the measuring roll body or, for example, relative to the center of the measuring roll body. Additionally or alternatively, the measuring roll can be used to detect the flatness of the strip-shaped article. Additionally or alternatively, the measuring roll can be used to detect the strip width. Additionally or alternatively, the measuring roll can be used to detect the strip speed. Additionally or alternatively, the measuring roll can be used to detect the temperature of the strip-shaped article. In a particularly preferred embodiment, the measuring roll can be used to measure the strip tension as the strip article is pulled through the measuring roll, and to detect the position of the strip article, represented by the position of the centerline of the strip article relative to a reference point, e.g. relative to a side of the measuring roll body or, e.g. relative to the center of the measuring roll body, and / or to detect the position of the edge of the strip article on the circumferential surface of the measuring roll, represented by the position of the edge of the strip article relative to a reference point, e.g. relative to a side of the measuring roll body or, e.g. relative to the center of the measuring roll body, and to detect the temperature of the strip article, in order to detect the flatness of the strip article.

[0112] The force sensor according to the invention has a piezoelectric material and a polygonal sensor surface.

[0113] Particularly preferably, the force sensor comprises a piezoelectric quartz.Particularly preferably, the piezoelectric quartz is a plate.

[0114] In a preferred embodiment, the piezoelectric material has a polygonal, particularly preferably rectangular, particularly preferably square, cross-section.

[0115] Particularly preferably, the force sensor has a rectangular, particularly preferably square, sensor surface. In a preferred embodiment, the sensor surface is the surface of a block arranged above the piezoelectric material. Particularly preferably, the block is located on the side facing the sensor surface on the piezoelectric material, particularly preferably on piezoelectric quartz, particularly preferably on a plate made of piezoelectric quartz. In a preferred embodiment, the block has a polygonal, particularly preferably rectangular, particularly preferably square cross section in a plane parallel to the sensor surface and / or in a plane perpendicular to the sensor surface.

[0116] In a preferred embodiment, the sensor surface is a raised surface on one side of the block, which is in a plane parallel to the sensor plane and which rises above an edge surface facing in the same direction as the sensor surface. In a preferred embodiment, the outer contour of the edge surface is a polygon, particularly preferably a rectangle, particularly preferably a square. In a preferred embodiment, the outer contour of the edge surface is an enlargement of the periphery of the sensor surface. In a preferred embodiment, the centre point of the outer contour of the edge surface corresponds to the centre point of the outer contour of the sensor surface.

[0117] In a preferred embodiment, the force sensor comprises a casing, which in a preferred embodiment surrounds the piezoelectric material together with the block.

[0118] In a preferred embodiment, the casing has a side surface, particularly preferably an annular side surface, and an edge extending at an angle, preferably at a right angle, to the side surface, particularly preferably an annular edge. In a preferred embodiment, the edge of the casing lies on the edge surface of the block.

[0119] In a preferred embodiment, the force sensor comprises: an upper block, which rests on the side facing the sensor surface on an upper piezoelectric material, particularly preferably on an upper piezoelectric quartz, particularly preferably on an upper plate made of piezoelectric quartz; an upper plate made of upper piezoelectric material, particularly preferably upper piezoelectric quartz, particularly preferably made of piezoelectric quartz; a lower plate made of a lower piezoelectric material, particularly preferably a lower piezoelectric quartz, particularly preferably made of piezoelectric quartz, and a lower block with a lower surface which, on the side opposite to the lower surface, is in contact with a lower piezoelectric material, particularly preferably with a lower piezoelectric quartz, particularly preferably with a lower plate made of piezoelectric quartz; It has.

[0120] In a preferred embodiment, the casing has an upper edge extending at an angle to the side surface and a lower edge extending at an angle to the side surface. In a preferred embodiment, the casing encircles and grips the package consisting of the upper block, the upper piezoelectric material, the lower piezoelectric material and the lower block. In a preferred embodiment, this encircling grip generates a preload. In a preferred embodiment, the force sensor according to the invention is produced by mounting a two-part casing, the casing having an upper part with an upper edge and a lower part with a lower edge. The upper part is in contact with the upper block at its upper edge and the lower part is in contact with the lower block at its lower edge. A compressive force is applied to the package consisting of the upper block, the upper piezoelectric material, the lower piezoelectric material and the lower block. The upper and lower parts of the casing are connected to each other in this state, for example by a joining method, for example by gluing, or by welding, for example by laser welding or by brazing. The parts of the casing which are joined together in this way do not allow the package to relax, or only partially so, so that a preload caused by the encircling grip is created.

[0121] In a preferred embodiment, the force sensor has built-in impedance converter electronics, which in a preferred embodiment is implemented as a FET circuit, converting the high impedance signal of the piezoelectric material into a voltage signal with a low impedance, for example around 100 ohms. In a preferred embodiment, the supply current and the sensor signal are transmitted together via a coaxial cable.

[0122] In a preferred embodiment, the sensor electronics is supplied with a constant current, for example 2-20 mA. Via the sensor, a positive working point voltage can be formed, typically 8-12 V, when the constant current is supplied. The actual measurement signal of the sensor is superimposed on this working point voltage as an alternating voltage. The bias voltage of the power supply is, for example, 24-30 V, so that symmetrical modulation possibilities are obtained in the positive and negative direction.

[0123] In a preferred embodiment, the lower block also has a sensor surface, particularly preferably formed as a raised surface beyond the surrounding edge surface.

[0124] The measuring roll according to the invention for detecting the properties of a strip-shaped article, in particular a metal strip, guided over the measuring roll comprises: a measuring roll body having a peripheral surface, at least one recess in the measuring roll body, which is spaced apart from the circumferential surface or leads from the circumferential surface into the interior of the measuring roll body, and a first force sensor arranged in a recess and a second force sensor arranged in the recess or in another recess adjacent to the first recess; It has In a measuring roll, a first force sensor has a sensor surface, the first force sensor being capable of generating a sensor signal when a position of the sensor surface of the first force sensor changes, and a second force sensor has a sensor surface, the second force sensor being capable of generating a sensor signal when a position of the sensor surface of the second force sensor changes, the first force sensor is disposed adjacent to the second force sensor within the recess, the sensor surface of the first force sensor being directly adjacent to the sensor surface of the second force sensor; or the first force sensor has an end boundary line extending in the radial direction of the measuring roll and intersecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor; extends in a plane that includes a line connecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and a point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor, and the end boundary line; and - Intersects with the end boundary line at the intersection point between the end boundary line and the perimeter, and The first force sensor is disposed adjacent to the second force sensor such that an angle between the line intersecting the point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor is less than 65°; and The measuring roll is characterized in that it comprises a force sensor according to the invention.

[0125] The measuring roll according to the invention can likewise be further embodied in the manner of the above-mentioned special embodiments and can, for example, be equipped with a temperature sensor and can, for example, have a plurality of force sensors according to the invention.

[0126] The invention will now be explained in more detail with reference to the illustrated embodiment. [Brief description of the drawings]

[0127] [Figure 1] FIG. 2 is a side view, partially in section, of a first embodiment of a measuring roll. [Diagram 2] FIG. 2 shows a measuring roll with cable passage in a perspective view with the cover removed; [Diagram 3] 3 is a diagram showing a part of an end surface of the measuring roll of FIG. 2. FIG. [Figure 4] FIG. 2 shows a perspective view of a measuring roll with force sensors arranged stepwise along a spiral, with the cover removed. [Diagram 5]FIG. 13 is a detailed cross-sectional view of a force sensor disposed within a hole. [Figure 6] FIG. 6 is a plan view showing the arrangement of the force sensors in FIG. 5. [Figure 7] FIG. 13 is a side view, partially in section, of another embodiment of a measuring roll. [Figure 8] FIG. 10 is a cross-sectional view of a holder with a force sensor partially shown in a state of installation in a measuring roll in a side view cut along the line BB in FIG. 9 . [Figure 9] 9 shows the element of FIG. 8 in a view taken along line AA in FIG. 8. [Figure 10] 8 and 9 in a view taken along line CC in FIG. 9. FIG. [Figure 11] FIG. 10 is a view comparable to FIG. 9 showing an alternative configuration of the holder. [Figure 12] FIG. 9 is a view comparable to FIG. 8 and shows another configuration of the holder. [Figure 13] 13 is a view along line AA of FIG. 12 showing the element of FIG. 12. [Figure 14] 12 and 13 in a view taken along line CC in FIG. 12. FIG. [Figure 15] 13 is a view comparable to FIG. 8 and FIG. 12 showing another configuration of the holder. FIG. [Figure 16] FIG. 4 is a detailed view of a force sensor arranged in a recess of the measuring roll. [Figure 17] FIG. 13 is a detailed view of another embodiment of a force sensor arranged in a recess of the measuring roll. [Figure 18] FIG. 2 is a diagram showing the forces acting on a measuring roll; [Figure 19] FIG. 2 is a schematic diagram of a measuring roll according to the invention with a partially shielded force sensor; [Figure 20] 1 shows a partially schematic side view and a plan view of a ring-shaped force sensor which can be used in the measuring roll according to the invention and in the method according to the invention; [Figure 21]21 shows the measurement signal profile of the ring-shaped sensor shown in FIG. 20 with the same force per area and increasing sensor coverage in the axial direction. [Figure 22] FIG. 21 shows a schematic diagram of the sensitivity areas and the measurement signal shape in the axial and radial sensitivity directions of the ring-shaped force sensor shown in FIG. 20. [Figure 23] 1 shows a partially schematic side view and a plan view of a square-shaped force sensor which can be used in the measuring roll according to the invention and in the method according to the invention; [Figure 24] FIG. 24 shows the measurement signal curve for the square-shaped sensor shown in FIG. 23 with the same force per area and increasing sensor coverage in the axial direction. [Diagram 25] 24 is a diagram showing a schematic diagram of a sensitivity region and a measurement signal shape in the axial and radial sensitivity directions of the force sensor formed in a square shape shown in FIG. 23. FIG. [Figure 26] FIG. 24 is a diagram illustrating a schematic diagram of a sensitivity area and a measurement signal shape in the axial and radial sensitivity directions of the square-shaped force sensor shown in FIG. 23 when the force sensor is arranged without any gap between adjacent force sensors.

[0128] The measuring roll 1 according to the invention has a measuring roll body 1a with journals 2 and formed as a solid roll. In the measuring roll body 1a, a recess 3 is provided which is formed as a hole axially parallel to the longitudinal axis A of the measuring roll body 1a, from which a transverse passage 4 leads out near the end face of the recess and leads into a central cable passage 5. The recess 3 is closed at the end side by a cover 6 or by a respective separate cover and has a first force sensor 7a, a second force sensor 7b arranged adjacent to the first force sensor 7a, a third force sensor 7c arranged adjacent to the second force sensor 7b and a fourth force sensor 7d arranged adjacent to the third force sensor 7c, from which a cable 8 (shown only as one cable for the sake of simplicity) is guided to the outside via the hole 3, the transverse passage 4 and the central passage 5.

[0129] The measuring roll 1, shown in a schematic perspective view in Figures 2 and 3 with the cover 6 removed, has cable passages 10, 11 located opposite each other and parallel to each hole 3 for lines guided to the outside via the lateral passages 4 and the central passage 5.

[0130] The holes extend from both end faces of the roll 1 as shown in Figures 4 and 5 and have various depths as blind holes, so that the individual sensors are arranged along the spiral 20, i.e. in stages, and collectively detect the entire width of the roll 1.

[0131] Compared with the embodiment of Figures 1 to 3, the embodiment of Figures 4 and 5 has a roll body 1a formed as a solid roll having multiple grooves formed on its outer periphery, and these grooves are covered with a cover tube 1b that closes the grooves and forms a recess for the force sensor 7.

[0132] As shown in Fig. 4, each recess 3 can be formed in such a way that only one force sensor 7 is arranged therein. However, in the embodiment of Fig. 4, recesses 3 are also provided which have several force sensors 7. In the embodiment of Fig. 4, the recesses 3 are configured to lead from one end face of the measuring roll body 1a to the opposite end face of the measuring roll body.

[0133] FIG. 5 shows the arrangement of two force sensors 107a, 107b in a hole 103 in the measuring roll body 1a of a measuring roll, which is configured as a solid roll according to the construction shown in FIGS. 1 and 2 and has an axial hole 103 in the solid roll. Each of the force sensors 107a, 107b shown in FIG. 5 has a housing 120. A socket 122 is attached to one side of each housing 120. Each force sensor 107a, 107b has a respective piezoelectric element 113 made of a multilayer crystal assembly. Each piezoelectric element 113 is located between two force transmission disks 114, 115. The force transmission disks 114, 115 are connected to the housing 120 by means of an elastic flange 116. The sensor surface of the force sensor 107a is the outer surface of the force transmission disk 114, which contacts the wall of the hole 103. The sensor surface of the force sensor 107 b is the outer surface of the force transmission disk 114 in contact with the hole wall of the hole 103 .

[0134] In Fig. 5, for the force sensor 107a, an edge boundary line 117 is drawn, which extends in the radial direction of the measuring roll, and which intersects with the point of the sensor surface of the first force sensor 107a which is closest to the sensor surface of the second force sensor 107b. Furthermore, in Fig. 5, a line 118 is drawn, which corresponds to extends in a plane including a line connecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and a point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor, and the end boundary line 117; and The end boundary line 117 intersects with the peripheral surface at an intersection 119 between the end boundary line 117 and the peripheral surface, · It intersects with the point on the sensor surface of the second force sensor 107b that is closest to the sensor surface of the first force sensor 107a.

[0135] As shown in FIG. 5, the angle α between the end boundary line 117 and the line 118 is less than 65°, ie, approximately 45°.

[0136] The hole 103 is formed to have a rectangular cross section so that the annular, flat sensor surfaces of the force sensors 107a and 107b can abut against the wall of the hole 103.

[0137] 6 shows a schematic plan view of the force sensors 107a, 107b arranged in the hole 103, cut at the height of the upper hole wall, in which a line 123 is drawn connecting the point on the sensor surface of the first force sensor 107a that is closest to the sensor surface of the second force sensor 107b and the point on the sensor surface of the second force sensor 107b that is closest to the sensor surface of the first force sensor 107a. The sensor surface of the force sensor 107a is the outer surface of the force transmission disk 114 that is in contact with the hole wall of the hole 103. The sensor surface of the force sensor 107b is the outer surface of the force transmission disk 114 that is in contact with the hole wall of the hole 103.

[0138] The measuring roll 201 shown in FIG. 7 has a measuring roll body 201a formed as a solid roll, the circumference of which is provided with a number of recesses 203, 203a, 203b distributed over the roll width, in which an encoder is mounted, for example a distance or force or piezo encoder 207 in the form of a quartz washer for measuring dynamic and static forces, together with a cylindrical cover 234. The encoder 207 extends between a bottom surface 239 of the recess 203 and the cover 234. The cover 234 has a recess in which a head 236 of a tightening screw 237 is located, which engages in a threaded hole 238 of the measuring roll 201. The tightening screw 237 tightens the cover 234 together with the encoder 207 towards the bottom surface 239 of the recess 203.

[0139] The cover 234 is provided with a plastic layer 240. A gap 241 exists between the encoder 207 and the wall of the recess 203 of the roll 201 due to the difference between the diameter of the encoder and the diameter of the recess 203, and this gap is closed to the outside by the plastic layer 240 or in other ways when the cover is installed. A gap may also exist between the encoder cover and the wall of the recess.

[0140] 7 shows holes 203b arranged side by side on a line extending parallel to the longitudinal axis A of the measuring roll body 201a. A line connecting a point on the sensor surface of each force sensor 207 in one recess 203b that is closest to the sensor surface of the adjacent force sensor 207 in the adjacent recess 203b and a point on the sensor surface of the adjacent force sensor 207 in the adjacent recess 203b that is closest to the sensor surface of each force sensor 207 in the aforementioned recess 203b extends parallel to the longitudinal axis A of the measuring roll body 201a in the case of these holes 203b.

[0141] 7 shows, however, holes in the form of holes 203a that are adjacent to each other but are not arranged on a line extending parallel to the longitudinal axis A of the measuring roll body 201a. The line connecting the point of the sensor surface of each force sensor 207 in the recess 203a that is closest to the sensor surface of the adjacent force sensor 207 in the adjacent recess 203a, projected parallel to a plane containing the longitudinal axis A of the measuring roll body 201a, and the point of the sensor surface of the adjacent force sensor 207 in the adjacent recess 203a that is closest to the sensor surface of each force sensor 207 in said recess 203a, extends at an angle to the longitudinal axis A of the measuring roll body 201a in the case of these holes 203a.

[0142] The metering roll body 201a can be constructed with a coating, not shown, to form a closed circumference.

[0143] In Fig. 7, further individually formed holes 203 are provided. Fig. 7 thus shows that various arrangements of holes 203, 203a, 203b can be integrated on one measuring roll depending on the desired measurement task. However, configurations in which only holes 203b or only holes 203a are provided are also conceivable.

[0144] 8 shows a holder 1101 for a force sensor 1102. The holder 1101 holds the force sensor 1102 in an axial bore 1103 of a partially shown measuring roll 1104. The holder 1101 has an inner sleeve 1105 with a first inner wedge element 1106 arranged above an installation position provided for the force sensor 1102, the inner wedge element having an inner surface 1107 facing the installation position of the force sensor 1102 and an outer surface 1108 at an angle to the inner surface 1107 and facing the inner surface 1107. Furthermore, the inner sleeve 1105 has a second inner wedge element 1109 arranged below the mounting position provided for the force sensor 1102, and this inner wedge element has an inner surface 1110 facing the mounting position of the force sensor 1102 and an outer surface 1111 that is angled relative to the inner surface 1110 and faces the inner surface 1110.

[0145] The holder 1101 further comprises an outer sleeve 1112. The outer sleeve 1112 comprises a first outer wedge element 1113 having an inner surface 1114 facing the mounting position of the force sensor and an outer surface 1115 angled relative to the inner surface 1114 and facing the inner surface 1114. The outer sleeve 1112 further comprises a second outer wedge element 1116 having an inner surface 1117 facing the mounting position of the force sensor 1102, with which the second outer wedge element 1116 rests on the outer surface of the second inner wedge element 1109. The outer wedge element 1116 further comprises an outer surface 1118 facing the inner surface 1117.

[0146] The compression screw 1119, which has an external thread, screws into the internal thread 1120 on the outer sleeve. The depth of the compression screw 1119 determines the relative position of the inner sleeve 1105 with respect to the outer sleeve 1112 and thus also the degree of preload of the holder 1101 in the axial recess 1103.

[0147] As can be seen from FIG. 9, the inner sleeve 1105 and the outer sleeve 1112 have slots 1121 and 1122. These longitudinal slots 1121, 1122 reduce the spring stiffness of the inner sleeve 1105 and the outer sleeve 1112 and serve to keep the force branching small. The pressing force to be detected, acting in the direction of action of the arrow D, is thus well introduced into the force sensor 1102. The outer sleeve 1112 and the inner sleeve 1105 are produced by turning in a first work step by a cutting process. This allows for particularly precise production, particularly with regard to the geometrical tolerances of the inner surfaces 1114, 1117 of the outer sleeve 1112 and the outer surfaces 1108, 1111 of the inner sleeve, and allows a tilting-moment-free movement of the inner sleeve 1105 relative to the outer sleeve 1112. In a subsequent processing step, the regions of the inner sleeve 1105 located laterally as viewed in Fig. 9 can be further thinned in order to reduce the lateral wall thickness of the inner sleeve 1105. This results in lateral spaces 1123, 1124 as viewed in Fig. 9 between the inner sleeve 1105 and the outer sleeve 1112, which optimize the introduction of forces into the force sensor 1102 and further reduce the branching of forces.

[0148] 10 shows a top view of the force sensor 1102. In this view, the routing of the cables leading to the force sensor 1102 can be clearly seen. A first cable 1125 leads to the illustrated force sensor 1102, and another cable 1126 leads to another force sensor (not shown) located in the same axial recess 1103.

[0149] The alternative configuration of the holder shown in Figure 11 has essentially the same structure as the holder shown in Figures 8 to 10. The same components have reference numbers that are 100 higher. However, in the inner sleeve 1205 of this second embodiment, a number of cavities 1226 are provided, which further reduce the lateral wall thickness of the inner sleeve 1205 and thus further reduce the spring stiffness and thus the branching of forces.

[0150] Figures 12 to 14 show another embodiment of the invention, which differs from the embodiment shown in Figures 8 to 10 in that intermediate pieces 1327 and 1328 with spherical crowns are provided between the inner sleeve 1305 and the force sensor 1302. In other respects, the components shown correspond to those of the pieces shown in Figures 8 to 10. These components are designated by reference numbers 200 higher. Figures 12 and 13 further show that the outer sleeve 1312 can be provided with a temperature sensor 1350.

[0151] In Fig. 15 a holder 1401 is shown which is comparable to that shown in Fig. 8. It differs from that shown in Fig. 8 by a different orientation of the inner faces 1408, 1411 and the corresponding outer faces 1414, 1417 as well as by a tension screw 1429 which is screwed into the internal thread 1430 of the inner sleeve 1405. The screwing depth of the tension screw 1429 into the internal thread 1430 determines the position of the inner sleeve 1405 relative to the outer sleeve 1412 and thus the preload of the holder 1401 in the axial bore 1403 of the measuring roll 1404. The same components as those shown in Figs. 8 to 10 are designated by a number 300 larger.

[0152] Figure 16 shows a further configuration of the embodiment of figure 8, showing a detailed view of the force sensors 1102a, 1102b arranged in a pair in a recess 1103 of the measuring roll. A casing 1101 or a holder holds a first type of force sensor 1102a, designed for measuring radial forces, in a recess 1103 of the measuring roll, which is partially shown. The casing 1101 has an inner sleeve 1105 with a first inner wedge element 1106 arranged above the mounting position provided for the force sensor 1102a, which has an inner surface 1107 facing the mounting position of the force sensor 1102a and an outer surface 1108 facing the inner surface 1107 and at an angle to the inner surface 1107. Furthermore, the inner sleeve 1105 has a second inner wedge element 1127 arranged below the mounting position provided for the force sensor 1102a, and this inner wedge element has an inner surface 1110 facing the mounting position of the force sensor 1102a and an outer surface 1111 that is angled relative to the inner surface 1110 and faces the inner surface 1110.

[0153] Furthermore, the casing 1101 has an outer sleeve 1112 which has a first outer wedge element 1113 having an inner surface 1114 facing the mounting position of the force sensor 1102a and an outer surface 1115 which is angled with respect to the inner surface 1114 and faces the inner surface 1114. The outer sleeve 1112 further has a second outer wedge element 1120 having an inner surface 1117 facing the mounting position of the force sensor 1102a, with which the outer wedge element 1120 rests on the outer surface of the second inner wedge element 1127. The outer wedge element 1120 further has an outer surface 1116 which faces the inner surface 1117.

[0154] A compression screw 1119 with an external thread is screwed into an internal thread provided in the outer sleeve 1112. The screw-in depth of the compression screw 1119 determines the relative position of the inner sleeve 1127 with respect to the outer sleeve 1112 and thus also the degree of preload of the casing 1101 in the recess 1103. To detect the preload, a force sensor 1102b in the inner sleeve 1127 is arranged in the recess of the inner sleeve. By means of the force sensor 1102b the preload can be measured.

[0155] The force sensor 1102a for measuring the radial force is preloaded, the extent of which can be detected by the force sensor 1102b. For example, when heat is applied during the processing of a metal strip during hot rolling, the deflection of the strip under tension in the longitudinal direction introduces radial forces into the measuring roll, which elastically deform the outer skin of the measuring roll. The web, which is formed "diaphragm-like" above the recess 1103, is then displaced radially, which can be detected by the force sensor 1102a, which can be formed as a piezoelectric force sensor. Thermal stresses caused by the thermal gradient also cause a radial distance change in the circumferentially outer web above the recess 1103, which counteracts the radial force. This causes a change in the measurement result of the force sensor 1102a, and the change in distance due to the change in preload can be detected by the force sensor 1102b, which can be formed as a statically measuring force sensor, in particular as a strain gauge. The radial force value of the force sensor 1102a can be corrected in each case based on the actually measured preload.

[0156] A pair of force sensors 1102a, 1102b arranged adjacent to each other are mounted in a casing 1101 having an inner sleeve 1127 and an outer sleeve 1112 and are then positioned in a recess 1103 of the measuring roll 1 and clamped in place.

[0157] Fig. 17 shows a detailed view of the force sensors 1102a and 1102b arranged in the recess 1103 of the measuring roll 1 in an embodiment different from Fig. 16. The configuration of the embodiment as shown in Fig. 17 substantially corresponds to the configuration of the embodiment shown in Fig. 16. Only with regard to the arrangement and configuration of the force sensors 1102a and 1102b, the embodiment of Fig. 17 differs from the force sensors 1102a and 1102b of Fig. 16. The force sensor 1107a is configured as a piezoelectric force sensor and is somewhat shorter in the radial direction than the force sensor 1102a of Fig. 16. As a different type of force sensor, the force sensor 1107b is provided, which is configured as a statically measuring force sensor, in particular as a strain gauge.

[0158] Figure 18 shows the force exerted on a measuring roll by a metal strip partially wrapped around the measuring roll under strip tension. A quartz force sensor located in the recess of the measuring roll generates a charge that is directly proportional to the force exerted on the quartz.

[0159] The swath length deviation, usually measured in I-units, which is commonly used as an indication of swath flatness, is calculated according to the following relationship:

[0160] Local radial force N F R,i

[0161] Localized tensile force N F Z,i =F R,i / (2 × sin α / 2) α = belt deflection angle around the measuring roll

[0162] Local tensile stress N / mm 2 σ Z,i =F Z,i / (b El ×d)

[0163] b El = measurement area width d=band thickness

[0164] Tensile stress deviation N / mm 2 Δσ Z,i = σ Z,max ×σ Z,i

[0165] σ Z,max = maximum local constant tensile stress

[0166] Band length deviation μm / m ΔL / L i =(Δσ Z,i / E)×10 6 E = Modulus of Elasticity (Modulus of Elasticity of Steel = 2.06 x 10 5 N / mm 2 )

[0167] Band length deviation I-Unit ΔL / L i =(Δσ Z,i / E)×10 5 E = Modulus of Elasticity (Modulus of Elasticity of Steel = 2.06 x 10 5 N / mm 2 )

[0168] example Quartz force sensor: sensitivity = 4.2 pC / N Sensor charge:=210pC Force applied to the sensor: F R,i =50N F Z,i =50 / (2×0.342 / 2)=146.19Nα=20°σ Z,i =146.19 / (25×0.5)=11.69N / mm 2 b El =25mm,d=0.5mmΔσ Z,i =20-11.69=8.3N / mm 2 σ Z,max =20N / mm 2 ΔL / L i =(Δσ Z,i / E)×10 6 = 162.34 μm / m E = Elastic modulus (Elastic modulus of steel = 2.06 x 10 5 N / mm2 ) ΔL / L i =(Δσ Z,i / E)×10 5 =16.234 I-Unit

[0169] Fig. 19 shows a schematic view of a measuring roll 1 according to the invention with partially covered force sensors 7b, 7h. The measuring roll 1 is shown with journals 2, a measuring roll body 1a formed as a solid roll and force sensors 7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i. Sensors 7c, 7d, 7e, 7f, 7g are completely covered by the diagrammatically shown strip. Sensors 7a and 7i are not covered. Sensors 7b and 7h are partially covered.

[0170] FIG. 20 shows a schematic partial side view and a plan view of a ring-shaped force sensor as can be used in the measuring roll according to the invention and in the method according to the invention. The sensor comprises two blocks 2001 and 2002. The outwardly facing surfaces of blocks 2001 and 2002 are each provided with an exposed sensor surface. Block 2001 rests on an upper quartz disk 2003. The upper quartz disk is arranged above a lower quartz disk 2004. The lower block 2002 is in contact with the lower quartz disk 2004. The force sensor can have integrated impedance converter electronics (not shown in detail). Both the supply current and the sensor signal can be transmitted via a coaxial cable 2005. The force sensor has a height H and a diameter D. The force sensor has an axial hole 2006.

[0171] FIG. 21 shows the measurement signal profile for the ring-shaped sensor shown in FIG. 20 with the same force per area and an increased axial sensor coverage. For a sensor with a ring configuration, the sensor signal increases with the same force per area (N / mm 2) is not proportional to the increase in axial sensor coverage. By axial coverage is meant the proportion of the strip that is covered. In FIG. 19, the axial coverage at force sensor 7b is clearly higher than, for example, the axial coverage at force sensor 7h in FIG. 19. The axial coverage of force sensor 7h increases compared to the strip edge position shown in FIG. 19 if the strip edge is moved from the position shown in FIG. 19 to the right in FIG. 19, i.e. along the axis of the measuring roll 1, and thus sensor 7h is covered even more. In the case of complete coverage, the sensor coverage in % is 100%.

[0172] Fig. 22 shows the sensitivity area and the measurement signal shape diagrammatically in the axial and radial sensitivity directions of the ring-shaped force sensor shown in Fig. 20. Fig. 22 shows the sensitivity area for the example of a force sensor mounted in an axial bore (see Fig. 1) at a distance from the circumferential surface. The sensitivity area represents the area on the circumferential surface of the measuring roll where the application of a force will be recognized by the force sensor. All forces acting anywhere on the sensitivity area on the circumferential surface of the measuring roll are detected by the force sensor (results in a force sensor signal). The measurement signal shape shows what height of the measurement signal will generate if a force acts on the circumferential surface of the measuring roll at a given point in the sensitivity area.

[0173] Fig. 23 shows a schematic partial side view and a plan view of a square-shaped force sensor that can be used in the measuring roll according to the invention and in the method according to the invention. The sensor comprises two blocks 2011 and 2022. The outwardly facing surfaces of blocks 2011 and 2012 are each provided with an exposed sensor surface. Block 2011 rests on an upper quartz disk 2013. Upper quartz disk 2013 is arranged above a lower quartz disk 2014. Lower block 2012 is in contact with lower quartz disk 2014. The force sensor can have integrated impedance converter electronics (not shown in detail). Both the supply current and the sensor signal can be transmitted via a coaxial cable 2015. The force sensor has a height H, a width B and a length L. Width B and length L are equal.

[0174] Figure 24 shows the measurement signal curve for an increased axial sensor coverage at the same force per area for a square-shaped sensor as shown in Figure 23. In comparison with Figure 21, a linear relationship between coverage and measured value can be seen.

[0175] Figure 25 shows a schematic representation of the sensitive area and the measurement signal shape in the axial and radial sensitivity directions of a square-shaped force sensor as shown in Figure 23. In comparison with Figure 22, it can be seen that the sensitive area is narrower in the axial direction.

[0176] Fig. 26 shows a schematic representation of the sensitivity areas and measurement signal shapes in the axial and radial sensitivity directions of the sensor when a square-shaped force sensor according to Fig. 23 is arranged with no gap between adjacent force sensors. For clarity, adjacent force sensors are shown as dots in Fig. 26, each with a sensitivity area filled in with a dotted line. It is recognized that with such a configuration of the sensor (rectangular, particularly preferably square sensor surface), the axial position of the applied force can be detected more precisely. The sensitivity areas are extremely narrow in the axial direction.

Claims

1. 1. A method for detecting properties of a strip-like article, in particular a metal strip, guided through a measuring roll, comprising: In order to detect the characteristics of a strip-shaped article, in particular a metal strip, guided through a measuring roll, the strip-shaped article is guided through the measuring roll, the measuring roll comprising: a measuring roll body having a peripheral surface; At least one recess in the measuring roll body, the recess being spaced apart from the circumferential surface or leading from the circumferential surface into the interior of the measuring roll body; and a first force sensor disposed within the recess, and a second force sensor disposed within the recess or within another recess adjacent to the recess; and the first force sensor has a sensor surface and is capable of generating a sensor signal when a position of the sensor surface of the first force sensor changes, the second force sensor has a sensor surface and is capable of generating a sensor signal when a position of the sensor surface of the second force sensor changes, and the first force sensor is disposed adjacent to the second force sensor in the recess, the sensor surface of the first force sensor being adjacent to the sensor surface of the second force sensor; or the first force sensor has an end boundary line extending in a radial direction of the measuring roll and intersecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor; extends in a plane that includes a line connecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and a point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor, and the end boundary line; and - intersects with the end boundary line at an intersection of the end boundary line and the peripheral surface; and the first force sensor is disposed adjacent to the second force sensor such that an angle between the line intersecting the point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor is less than 65°; Guiding the web of material through the measuring roll such that the web of material is partially wrapped around the measuring roll; supplying to an evaluation unit a sensor signal generated by the first force sensor due to a change in position of the sensor surface of the first force sensor caused by a pressing force generated by wrapping; supplying to an evaluation unit a sensor signal generated by the second force sensor due to a change in position of the sensor surface of the second force sensor caused by a pressing force generated by wrapping; the evaluation unit generates information dependent on the sensor signal of the first force sensor and on the sensor signal of the second force sensor, The method according to claim 1, wherein the evaluation unit generates information corresponding to the strap tension when the strap-shaped article is guided through the measuring roll or directly proportional to the strap tension as the strap-shaped article is guided through the measuring roll, depending on the sensor signal of the first force sensor and the sensor signal of the second force sensor.

2. the web-shaped article guided through the measuring roll covers an area of ​​the circumferential surface of the measuring roll and guides the recess through said area at least once per revolution of the measuring roll, the recess extending parallel to the longitudinal axis of the measuring roll body and comprising a chain of force sensors at least across the width of said area oriented parallel to said longitudinal axis, each force sensor being arranged such that, with the exception of the last force sensor at each end of the chain, the sensor surface of the respective force sensor is adjacent to the sensor surface of the force sensor adjacent to the respective force sensor in the direction of the chain and adjacent to the sensor surface of the force sensor adjacent in the opposite direction of the chain to the respective force sensor, or each of said force sensors has an end boundary line extending in a radial direction of said measuring roll and intersecting a point of said sensor surface of said each of said force sensors that is closest to said sensor surface of said each of said force sensors adjacent to said each of said force sensors; extends in a plane that includes a line connecting a point on the sensor surface of the respective force sensor that is closest to the sensor surface of the adjacent force sensor and a point on the sensor surface of the respective force sensor that is closest to the sensor surface of the adjacent force sensor, and the end boundary line; and - intersects with the end boundary line at an intersection of the end boundary line and the peripheral surface; and - the angle between the line intersecting the point on the sensor surface of the force sensor adjacent to the respective force sensor closest to the sensor surface of the respective force sensor is less than 65° and is disposed adjacent to the force sensor adjacent to the respective force sensor in the direction of the chain; and each said force sensor having an end boundary line extending in a radial direction of the measuring roll and intersecting a point on the sensor surface of the respective force sensor that is closest to the sensor surface of the respective force sensor adjacent to the respective force sensor; extends in a plane that includes a line connecting a point on the sensor surface of the respective force sensor that is closest to the sensor surface of the adjacent force sensor and a point on the sensor surface of the respective force sensor that is closest to the sensor surface of the adjacent force sensor, and the end boundary line; and - intersects with the end boundary line at an intersection of the end boundary line and the peripheral surface; and The method of claim 1, wherein the force sensor is disposed adjacent to an adjacent force sensor in the opposite chain direction to the respective force sensor such that an angle between the line intersecting the point on the sensor surface of the force sensor adjacent to the respective force sensor closest to the sensor surface of the respective force sensor is less than 65°.

3. the web-like article guided through the measuring roll covers an area of ​​the circumferential surface of the measuring roll and guides a chain of recesses through said area at least once per revolution of the measuring roll, the recesses being arranged parallel to the longitudinal axis of the measuring roll body and at least over a width of said area oriented parallel to said longitudinal axis, one force sensor being arranged in each recess of the chain, each force sensor, except for the last force sensor at each end of the chain, having an end boundary line extending in the radial direction of the measuring roll and intersecting with a point of the sensor surface of the respective force sensor that is closest to the sensor surface of the respective force sensor adjacent to the respective force sensor; extends in a plane that includes a line connecting a point on the sensor surface of the respective force sensor that is closest to the sensor surface of the adjacent force sensor and a point on the sensor surface of the respective force sensor that is closest to the sensor surface of the adjacent force sensor, and the end boundary line; and - intersects with the end boundary line at an intersection of the end boundary line and the peripheral surface; and - disposed adjacent to a force sensor adjacent to the respective force sensor in the direction of the chain such that an angle between the line intersecting the point on the sensor surface of the force sensor adjacent to the respective force sensor closest to the sensor surface of the respective force sensor is less than 65°; and an end boundary line extending in a radial direction of the measuring roll and intersecting a point on the sensor surface of each of the force sensors that is closest to the sensor surface of the force sensor adjacent to the respective force sensor; extends in a plane that includes a line connecting a point on the sensor surface of the respective force sensor that is closest to the sensor surface of the adjacent force sensor and a point on the sensor surface of the respective force sensor that is closest to the sensor surface of the adjacent force sensor, and the end boundary line; and - intersects with the end boundary line at an intersection of the end boundary line and the peripheral surface; and The method of claim 1, wherein the force sensor is disposed adjacent to an adjacent force sensor in the opposite chain direction to the respective force sensor such that an angle between the line intersecting the point on the sensor surface of the force sensor adjacent to the respective force sensor closest to the sensor surface of the respective force sensor is less than 65°.

4. 4. The method according to claim 1, further comprising adding together a sensor signal of the first force sensor and a sensor signal of the second force sensor in the evaluation unit for generating the information.

5. 2. The method of claim 1, wherein the information indicates which force sensors are located, in a radial direction of the measuring roll body, below an area covered by the web of articles being guided through the measuring roll.

6. 6. The method according to claim 1, wherein the measuring roll has a temperature sensor, and the evaluation unit outputs, in addition to the information generated by the evaluation unit, the temperature measured by the temperature sensor or a value that depends on the temperature measured by the temperature sensor.

7. 7. The method according to claim 1, wherein the evaluation unit generates further information that depends on the flatness of the web of the article guided through the measuring roll, the further information being dependent on the sensor signal of the first force sensor and the sensor signal of the second force sensor.

8. The method according to any one of claims 1 to 7, wherein the evaluation unit detects the band edge position, which is the position of the edge of the band-shaped article, using the first force sensor and the second force sensor, both of which are arranged in one recess or in multiple recesses arranged close to each other, in a section of the measuring roll where the band edge position, which is the position of the edge of the band-shaped article, is expected, and calculates the band width.

9. Use of a measuring roll for detecting properties of a strip-like article, in particular a metal strip, guided through the measuring roll, the measuring roll comprising: a measuring roll body having a peripheral surface; At least one recess in the measuring roll body, the recess being spaced apart from the circumferential surface or leading from the circumferential surface into the interior of the measuring roll body; and a first force sensor disposed within the recess, and a second force sensor disposed within the recess or within another recess adjacent to the recess; It has the first force sensor has a sensor surface and is capable of generating a sensor signal when a position of the sensor surface of the first force sensor changes, the second force sensor has a sensor surface and is capable of generating a sensor signal when a position of the sensor surface of the second force sensor changes, in this case, the first force sensor is disposed adjacent to the second force sensor in the recess, the sensor surface of the first force sensor being adjacent to the sensor surface of the second force sensor; or the first force sensor has an end boundary line extending in a radial direction of the measuring roll and intersecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor; extends in a plane that includes a line connecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and a point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor, and the end boundary line; and - intersects with the end boundary line at an intersection of the end boundary line and the peripheral surface; and the first force sensor is disposed adjacent to the second force sensor such that an angle between the line intersecting the point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor is less than 65°; Using a measuring roll to measure the strip tension as the strip of material is pulled through the measuring roll.

10. A measuring roll for detecting a characteristic of a strip-like article, in particular a metal strip, guided through said measuring roll, said measuring roll comprising: a measuring roll body having a peripheral surface; At least one recess in the measuring roll body, the recess being spaced apart from the circumferential surface or leading from the circumferential surface into the interior of the measuring roll body; and a first force sensor disposed within the recess, and a second force sensor disposed within the recess or within another recess adjacent to the recess; It has a first force sensor having a sensor surface, the first force sensor being capable of generating a sensor signal when a position of the sensor surface of the first force sensor changes, and a second force sensor having a sensor surface, the second force sensor being capable of generating a sensor signal when a position of the sensor surface of the second force sensor changes, the first force sensor is disposed adjacent to the second force sensor in the recess, the sensor surface of the first force sensor being adjacent to the sensor surface of the second force sensor; or the first force sensor has an end boundary line extending in a radial direction of the measuring roll and intersecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor; extends in a plane that includes a line connecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and a point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor, and the end boundary line; and - intersects with the end boundary line at an intersection of the end boundary line and the peripheral surface; and the first force sensor is disposed adjacent to the second force sensor such that an angle between the line intersecting the point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor is less than 65°; The measuring roll has a temperature sensor, A measuring roll, characterized in that a line connecting a point on the sensor surface of the first force sensor that is closest to the sensor surface of the second force sensor and a point on the sensor surface of the second force sensor that is closest to the sensor surface of the first force sensor extends at an angle of greater than 10° with respect to a plane extending perpendicular to the longitudinal axis of the measuring roll.

11. The measuring roll body is formed as a solid roll and has a closed peripheral surface, All the recesses provided in the measuring roll body are formed so that there is no recess connected to the peripheral surface, 11. The measuring roll according to claim 10, characterized in that in the embodiment in which each of the recesses has a recess leading in the direction towards the circumferential surface, these recesses are closed by a closing element, i.e. a cover.

12. Use of a measuring roll as described in claim 10 or 11 for detecting the position of a strip-shaped article or for detecting the position of an edge of the strip-shaped article on the circumferential surface of the measuring roll.

Images