Method and system for maintaining constant force between roller and web during web forming operations

Abstract

Systems and methods for a rolling mill coiler are disclosed. Systems and methods for enabling a control scheme to maintain a constant force between a roller and a coil surface are disclosed. Exemplary systems and methods may include: forming a portion of a coil; capturing first coil data corresponding to a force of the coil while the metal strip is coiled into the coil; capturing second coil data corresponding to a position of the coil while the metal strip is coiled into the coil; determining a signal corresponding to a rolling force and a protrusion position of a roller; and transmitting the signal to a hydraulic cylinder coupled to the roller, the hydraulic cylinder causing the roller to apply a rolling force to counteract a radial force of the coil.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of and priority to U.S. Provisional Application No. 62 / 964,200, filed January 22, 2020, and entitled “SENSING AND OFFSETTING THEFORCE OF EVENTS IN A COIL FORMING OPERATION,” the contents of which are incorporated herein by reference in their entirety for all purposes. Technical Field

[0003] The present application relates to rolling mill coilers and, more particularly, to systems and methods for enabling a control scheme to maintain a constant force between a roll and the coil surface. Background Art

[0004] A metal ingot can be rolled into a metal strip during a rolling operation. A mill coiler can be used to roll the metal strip into a coil. When the metal strip is rolled into a coil, air can become trapped between the coil turns. This air entrapment can cause problems such as scratch defects and coil widening. Mill coilers can incorporate rollers that contact the coil surface into the rolling mill to limit air entrapment between coil turns. Bumps or protrusions in the coil can cause radial forces between the coil and the rollers, which can prevent a constant force between the coil and the rollers during coil rolling. Summary of the Invention

[0005] The terms "invention," "the invention," "this invention," and "present invention" as used in this patent are intended to refer broadly to all subject matter of this patent and the patent claims below. Statements containing these terms should not be construed to limit the subject matter described herein, or to limit the meaning or scope of the patent claims below. The embodiments of the invention covered by this patent are defined by the following claims, not by this Summary. This Summary is a high-level summary of various embodiments of the invention and introduces some concepts that will be further described in the Detailed Description section below. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used alone to determine the scope of the claimed subject matter. The subject matter should be understood by reference to appropriate portions of the entire specification of this patent, any or all of the drawings, and each claim.

[0006] An exemplary embodiment of the present technology may include a method. The method may include forming a portion of a coil from a metal strip, for example, by performing a coil forming operation using a coiling apparatus, the portion including a first coil and a second coil, wherein the second coil includes a protrusion; while coiling the metal strip into the coil, capturing, by a first sensor, first coil data associated with the coil during the coil forming operation, wherein the first coil data includes data corresponding to a radial force from the coil applied to a roller when the roller contacts the protrusion; while coiling the metal strip into the coil, capturing, by a second sensor, second coil data associated with the coil during the coil forming operation, wherein the second coil data includes data corresponding to a position of the coil when the roller contacts the coil; determining a signal corresponding to a rolling force of a roller and a position of the protrusion using the first coil data, the second coil data, and circuitry; and transmitting a signal to a hydraulic cylinder coupled to the roller, wherein upon receiving the signal, the hydraulic cylinder causes the roller to apply a rolling force, wherein the rolling force opposes the radial force of the coil.

[0007] In another aspect, the hydraulic cylinder causing the roller to apply a rolling force includes reducing the force applied by the roller. The method may further include determining data corresponding to the frequency of the coil over a period of time using a spool encoder electrically connected to the coil or an angular encoder mechanically connected to the coil. In another aspect, the circuit includes a set of self-tuning bandpass filters. In another aspect, each filter in the set of self-tuning bandpass filters is associated with a harmonic of the angular velocity of the coil. In another aspect, the protrusion in the second turn of the coil is at least partially formed by the leading edge of the first turn of the coil. In another aspect, the second coil data includes data corresponding to the position of the coil when the roller contacts the protrusion. In another aspect, the first sensor is a load cell electrically connected to the roller. In another aspect, the second sensor is a linear transducer electrically connected to the hydraulic cylinder. In another aspect, the roller is an ironing roller.

[0008] Another exemplary embodiment may include a system. For example, the system may include: a roller configured to contact a surface of a web, wherein the web is formed by a web-forming operation using a reel-up device; a load cell configured to capture first data corresponding to a first force imparted by the web in a first direction; a linear transducer configured to capture second data corresponding to a position of the web; a circuit configured to use the first data and the second data to determine a signal associated with a second force for counteracting the first force; and a hydraulic cylinder configured to receive the signal from the circuit and impart the second force to the roller in a second direction opposite the first direction.

[0009] In another aspect, the hydraulic cylinder that causes the roller to apply the rolling force is configured to reduce the force applied by the roller. In another aspect, the system further includes a shaft encoder electrically connected to the coil or an angular encoder mechanically connected to the coil, wherein the shaft encoder is configured to generate data corresponding to the frequency of the coil over a period of time. In another aspect, the circuit includes a set of self-tuning bandpass filters. In another aspect, each filter in the set of self-tuning bandpass filters is associated with a harmonic of the angular velocity of the coil. In another aspect, the portion of the coil includes a first coil formed from a metal strip and a second coil, wherein the second coil includes a protrusion, wherein the protrusion in the second coil is formed at least in part by a leading edge of the first coil. In another aspect, the second coil data includes data corresponding to the position of the coil when the roller contacts the protrusion. In another aspect, the roller is an ironing roller.

[0010] The various embodiments described in this disclosure may include additional systems, methods, features, and advantages that may not necessarily be explicitly disclosed herein but will be apparent to one of ordinary skill in the art after reviewing the following detailed description and accompanying drawings. All such systems, methods, features, and advantages are intended to be included within this disclosure and protected by the following claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] A further understanding of the nature and advantages of the various embodiments may be achieved by reference to the following drawings. The features and components of the drawings are illustrated to emphasize the general principles of the present disclosure. In the drawings, similar components or features may have the same reference numeral. Furthermore, various components of the same type may be distinguished by following the reference numeral with a dash and a second numeral that distinguishes the similar components. If only the first reference numeral is used in the specification, the description applies to any of the similar components having the same first reference numeral, regardless of the second reference numeral.

[0012] Figure 1 A coil formed from a metal strip is shown with air trapped within the coil.

[0013] Figure 2 A photograph showing an exemplary scratch defect on a metal strip is shown.

[0014] Figure 3 A coil formed from a metal strip is shown with rollers applying force to the coil in accordance with an embodiment of the present technology.

[0015] Figure 4 Shown is a coil formed from a metal strip and a protrusion in a second turn of the coil in accordance with an embodiment of the present technology.

[0016] Figure 5Shown are a series of coils formed from metal strips, protrusions in the coils, and rollers in accordance with embodiments of the present technology.

[0017] Figure 6 A web is shown having a roller and a hydraulic cylinder system configured to control the roller in accordance with an embodiment of the present technology.

[0018] Figure 7 An exemplary control system for maintaining a constant force throughout the reeling process is shown in accordance with an embodiment of the present technology.

[0019] Figure 8 The present invention is shown as an embodiment of the present invention. Figure 7 A series of exemplary filters that form part of a control system are shown in FIG.

[0020] Figure 9 is an exemplary flow chart of an exemplary process according to an embodiment of the present technology. DETAILED DESCRIPTION

[0021] The subject matter of the examples of the present invention is described in detail herein to meet statutory requirements, but this description is not necessarily intended to limit the scope of the claims. The claimed subject matter may be embodied in other ways, may include different elements or steps, and may be used in conjunction with other existing or future technologies. This description should not be construed to imply any specific order or arrangement among or between the various steps or elements, except where the order of the steps or arrangement of the elements is explicitly described.

[0022] The present application relates to rolling mill coilers. More specifically, a system and method are disclosed for enabling a control scheme to maintain a constant force between the rollers and the surface of the coil. As the coil size increases over time, the rollers may move in an arcuate motion to follow the roll gap.

[0023] A metal ingot can be rolled into a metal strip during a rolling operation. A coiler and a coiling operation can be used to roll the metal strip into a coil. When the metal strip is rolled into a coil, air may be trapped between the turns of the coil. Air entrapment may cause problems such as scratch defects and coil widening. A rolling mill coiler may incorporate rollers that can contact the surface of the coil into the rolling mill to limit air entrapment between the turns of the coil. Bumps or protrusions in the coil may cause radial forces between the coil and the rollers, which may prevent a constant force between the coil and the rollers during coil rolling. The terms "bump" and "protrusion" are used interchangeably herein.

[0024] More specifically, even though the rolled metal strip may be small due to its thin nature, it has a width, and therefore the leading edge of the strip has a non-zero height. When the strip begins to wind on a coiler, the leading edge of the strip may begin the first turn of the coil. When the second turn of the coil begins, the second turn of the strip will sit on top of the leading edge of the strip, causing a protrusion. The protrusion may be caused by the width of the leading edge of the coil and the distance between the outer surface of the first turn of the coil and the coiler drum. The rollers may contact the surface of the coil at the nip of the coil (a coil's "nip" may be the point where two coils, such as a coil and an incoming metal strip, come into contact). When the protrusion caused by the first turn of the coil and the nip is at the same location around the circumference of the coil, the protrusion may induce additional radial force from the coil to the rollers. This additional force may cause the force between the rollers and the coil to become inconsistent. The control scheme may use eccentricity compensation to maintain a constant force between the rollers and the coil surface throughout the process, even when such a protrusion is present in the coil.

[0025] Figure 1 A coil is shown formed from a metal strip with air trapped within the coil. Metal strip 102 can be fed onto a reel 106. After multiple turns of metal strip 102 have been stacked on top of each other around reel 106, the metal strip constitutes coil 101. As reel 106 (and coil 101) rotates, more of metal strip 102 is stacked onto the coil and causes the coil's diameter to increase.

[0026] As coil 101 rotates and metal strip 102 moves toward coil 101, air can flow along the surface of the metal strip, as indicated by airflow arrows 108. Consequently, air can become trapped between metal strip 102 and coil 101. If air is trapped between metal strip 102 and coil 101, or in other words, between different turns of the metal strip when part of coil 101, the air can occupy the space between the turns and, when part of the coil, can prevent the turns from coming together as intended. This space and air between the turns of the metal strip can have several negative consequences. First, particles can become trapped between the turns of the coil. Second, because the turns may not be fully in contact with each other, the turns may move relative to each other. When two turns of the coil have less contact with each other, that is, when more air is trapped between them, there may be less friction between the two turns. When a particle (e.g., dirt or dust) is trapped between two coils and the coils move relative to each other (e.g., slide or roll), the particle may scratch the strip as it moves, which may be referred to as a "scratching defect," an example of which is shown in FIG. Figure 2Other potential negative effects can also occur. For example, rollers such as ironing rollers include coatings that can deform under loads, such as the additional load caused by the bouncing of protrusions in the web. In another example, the cyclical nature of the forces from the protrusions can generate excessive heat, leading to roller coating failure. The eccentricity compensation control scheme described herein is designed to reduce the impact of web protrusions on the forces applied by the rollers to the web surface.

[0027] Figure 2 A picture of an exemplary scratch defect on a metal strip is shown. Image 110 shows a scratch defect that appears on a metal strip 113 (which may be similar to, for example, Figure 1 Scratch defects on the metal strip 102). Figure 2 As shown, the rolling direction is from the bottom to the top of the image 110. The defect may appear as one or more close scrapes in the rolling direction. If there are multiple scrapes in the rolling direction, there may also be horizontal cross-width scrapes connecting the scrapes in the rolling direction.

[0028] Image 111 shows a 3-D scan of the surface of a scratch defect on a metal strip 114. The recessed areas in section 113 of strip 114 indicate scratches, while the raised areas indicate the cause of the scratches—small particles that have become trapped between the coil's turns. As the turns move relative to each other, the particles can scratch the strip as it slides and rolls. Movement between turns typically occurs in the rolling direction, but the coil can also experience lateral movement, resulting in lateral scratches instead.

[0029] Preventing coils from moving relative to each other and / or preventing air (and therefore particles) from being trapped between coils can help prevent scratch defects. Both of these issues can be addressed by pressing adjacent coils of coil against each other so that there is minimal or no space between the coils. For example, the more contact two coils have with each other, the greater the friction that exists between the two coils. Rollers (such as ironing rollers) can be used to press the latest coil from the incoming metal strip against the previous coil that has already been wound around the coil.

[0030] Figure 3A coil formed from a metal strip is shown with a roller applying a force to the coil according to an embodiment of the present technology. Roller 320, such as an ironing roller, can contact metal strip 302 and / or coil 301 and can apply force 316 to metal strip 302 and / or coil 301. Force 316 applied by roller 320 can cause metal strip 302 to contact the top turn of coil 301, thereby creating friction between the top turn of coil 301 and the most recent turn of coil 301, i.e., metal strip 302. This friction can cause the turns to not move relative to each other or to move minimally, which can prevent air from being trapped between the turns and, therefore, prevent one or more particles from causing scratch defects or other defects or negative effects.

[0031] Roller 320 can be made of, for example, a polymer material to allow for the required compliance during the roll-up process. In an example of the present technology, roller 320 can be made of steel, which can allow for greater force to deflect and stabilize the roll. Furthermore, additional rolls can be used in conjunction with roller 320; two or more rollers can be included in the system and used individually or simultaneously.

[0032] Figure 4 A coil formed from a metal strip and a protrusion in the second turn of the coil are shown, according to an embodiment of the present technology. Coil 402 can include many different "turns" of coil. For example, a turn can be a portion of the metal strip that is wrapped around the coil once. Thus, the length of each turn of the coil may be slightly different from the length of each additional turn of the coil, as the circumference of the coil may vary each time a new turn is added to the coil.

[0033] The leading edge 426 of the metal strip may begin the first turn 422 of the coil 402. When the second turn 424 of the coil begins, the second turn 424 of the metal strip may be located on top of the leading edge 426 of the metal strip, thereby creating a bump or protrusion 428 in the metal strip. Protrusion 428 may be caused by the thickness T of the leading edge of the coil and the distance between the outer surface of the first turn of the coil and the coiler drum. In other words, the diameter of the coil 402 at the protrusion may be slightly larger than the diameter of the coil at other parts of the coil (e.g., approximately the thickness T of the metal strip). This diameter may gradually increase at the beginning of the protrusion, and the maximum diameter of the coil may include the diameter of the coil elsewhere on the coil plus the thickness T of the metal layer. Due to the gradual change in protrusion thickness throughout the protrusion itself, the diameter of the coil may gradually vary throughout the protrusion. The rollers may move in an arc so that as the coil size increases, the rollers follow the roller gap.

[0034] As more turns are added to the coil, the size of the protrusion 428 can decrease. For example, the protrusion can be largest at the second turn of the coil. As more turns of coil are added to the coil, the protrusions on these turns may become smaller and smaller compared to the protrusions on the previous turns of coil.

[0035] Figure 5 A series of coils, protrusions in the coils, and rollers formed from metal strips according to embodiments of the present technology are shown. Figure 4 As noted, when the second turn of a coil (e.g., coil 501) begins, the second turn of the coil may be located on top of the leading edge of the metal strip, thereby creating a protrusion 528 in the metal strip. A roller 520 (such as an ironing roller) may be used to press the second (or subsequent) turn from the incoming metal strip against the turn before it, which has been wrapped around the coil. The roller 520 may contact the surface of the coil 501 at the nip of the coil. The coil 501 and the roller 520 exert forces on each other, including a radial force 516 from the roller to the coil and a radial force 517 from the coil to the roller. When the protrusion caused by the first turn of the coil and the nip is at the same location around the circumference of the coil, the protrusion may result in an increase in the radial force 517' from the coil to the roller, as shown. Figure 5 (c) This increased force may be a dynamic or acceleration force induced by the coil, which may result in a spike in coil loading and potentially damage the metal strip being wound. This increased force may cause the overall force between the roller and the coil to become inconsistent. In other words, protrusion 528 may cause the force applied to the coil surface to increase, causing the combined force between coil 501 and roller 520 to become unbalanced as the roller moves over protrusion 528. Similarly, after roller 520 moves over protrusion 528, the radial force 517 from coil 501 to roller 520 may decrease again. Thus, while the force between coil 501 and roller 520 may be constant throughout most of each coil winding, the constant force may be interrupted by protrusion 528. The protrusion may also cause roller 520 to briefly and temporarily lift off the surface of the metal strip, or "bounce" from the surface of the coil.

[0036] The control scheme can use eccentricity compensation to maintain a constant force between the web 501 and the roller 520, even when there is an eccentricity disturbance (such as a protrusion in the web). For example, to compensate for the increased radial force 517' caused by the web 501, the force 516 from the roller 520 can be reduced, which can be in the opposite direction of the web force so that the combined force remains constant throughout the winding process. The control scheme can be configured to determine what the reduction in force should be in order to offset the increased web force from the web 501.

[0037] Figure 6A web having rollers and a hydraulic cylinder system 600 configured to control the rollers is shown according to an embodiment of the present technology. As noted herein, rollers 620 (such as ironing rollers) can be configured to apply force to the loops of web 601 to prevent air and other debris from being trapped between the loops of the web and, thus, prevent possible damage to the web. The force applied by rollers 620 can be controlled by a hydraulic cylinder system, such as Figure 6 shown.

[0038] The hydraulic cylinder system can include a first sensor, such as a load cell 630, coupled to roller 620 or web 601. Load cell 630 is a force sensor that, when connected to a roller (either directly to the web or through a roller), can return a signal proportional to the mechanical force applied by web 601 to roller 620, such as the force caused by a protrusion in the web (e.g., protrusion 528) as described herein. For example, load cell 630 can return a signal proportional to the mechanical force applied by roller 620, which can represent the force applied by web 601 to roller 620. Thus, load cell 630 in turn captures a signal representing the amount of force required to push the web downward to counteract the upward force of the web to maintain a constant force between roller 620 and web 601. The signal (e.g., signal 641), which can represent the force applied by web 601 to roller 620, can be transmitted to another device or group of devices, such as a circuit, for further processing.

[0039] The hydraulic cylinder system may also include a hydraulic cylinder 632. The hydraulic cylinder 632 may be coupled to the roller 620 directly or through the load cell 630 and may control the position of the roller. Thus, for example, when the web 601 applies an increased force (such as the force 517') ​​to the roller 620, such as due to a protrusion in the web 601, the hydraulic cylinder 632 may be configured to pull the roller 620 away from the web 601, thereby counteracting the increased force applied by the web 601. Figure 6 shown and in Figure 7 As explored in more detail in , the hydraulic cylinder 632 can be electrically connected to other components, such as circuitry, which can transmit a signal to the hydraulic cylinder 632 that represents the adjustment force to be applied by the roller 620 controlled by the hydraulic cylinder 632.

[0040] The hydraulic cylinder system may also include a servo valve 636. The servo valve 636 is an electrically operated valve that controls how and how much hydraulic fluid is delivered to the hydraulic cylinder 632. In other words, the servo valve 636 may be configured to control the hydraulic cylinder 632 using, for example, a small electrical signal. The servo valve 636 may be configured to receive a signal from another device or group of devices, such as an electrical circuit (e.g., in FIG. Figure 7 The circuit (described further in ) receives signal 640, which may be indicative of the force that should be applied by roller 620 as controlled by hydraulic cylinder 632.

[0041] The hydraulic cylinder system may also include a second sensor, such as a linear transducer 634. The linear transducer 634 may be a position sensor configured to convert linear motion from, for example, the hydraulic cylinder 632 or the roller 620 into an electrical signal. For example, the linear transducer 634 may capture the position of the roller 620 or the web 601 and convert that information into a signal 642, which may then be sent to another device or group of devices, such as a circuit (e.g., in FIG. Figure 7 As an example, signal 642 can be used as part of a control scheme to determine the force to be applied to roller 620 to counteract the increased force on web 601, as described herein.

[0042] The hydraulic cylinder system may also include one or more accumulators 638. In some embodiments, because they are mounted in close proximity to the valve / cylinder, the accumulators 638 provide a direct source of hydraulic pressure. Without an accumulator, internal friction in the piping connecting the hydraulic pump to the valve may limit the speed of the hydraulic actuator. The accumulator can charge during periods when the bump is not set and discharge the system to maintain pressure during bump disturbances. With respect to the return line accumulator, the accumulator can act as a sink for draining fluid, thereby preventing return line pressure buildup caused by piping friction.

[0043] Figure 7 An exemplary control system 700 for maintaining a constant force throughout the reeling process is shown in accordance with an embodiment of the present technology. Figure 7 Shown, from Figure 6 The coil, roller and hydraulic cylinder system consists of 600 Figure 7 The control system 700 is part of the control system 700 in FIG. The control system 700 can be configured to predict the location of the protrusion in a controlled manner. For example, the control system 700 can be configured to determine when the protrusion is likely to come into contact with the roller. The control system 700 can also be configured to determine the force caused by the web 701 when the protrusion comes into contact with the roller. Determining these two characteristics of the rolling system can allow the system to counteract the upward force of the web by adjusting the downward force of the roller at the specific time when the roller comes into contact with the protrusion of the web.

[0044] When the coil in contact with the web moves over a protrusion in the web during the coiling process, as in Figure 4 and Figure 5Described in more detail, a load cell connected to the roller can detect an increase in force on the roller caused by a protrusion in the web. After the roller moves over the protrusion in the web, the load cell can detect a decrease in force back to its original force. To counteract this temporary increase in force, the roller can be configured to apply a temporarily reduced force to the web as the roller moves over the protrusion, and then increase the roller's reaction force again once the roller moves over the protrusion in the web. In this way, the system can be configured to adjust the roller so that the combination of the roller's downward force and the web's upward force is consistent or constant throughout the entire winding process (i.e., during periods when the roller is in contact with the protrusion and when it is not in contact with the protrusion).

[0045] The force load sensor and the linear transducer can collect data from the roller. The data can represent the force applied by the web received at the roller (e.g., captured by the force load sensor) and the position of the roller (e.g., captured by the linear transducer). Thus, data representing the force applied by the web when the protrusion is in contact with the roller and when the protrusion is not in contact with the roller, as well as the position of the roller and the web relative to each other, can be continuously captured. For example, the force load sensor and the linear transducer can collect such data during the first few turns (e.g., 2 turns, 3 turns, or 4 turns, etc.) of the winding process. Once the force and position data associated with the roller and the web are captured, the device can convert this data into signals and transmit them to the rest of the feedback control loop. For example, the linear transducer can capture position data and convert it into a position signal 742, which can then transmit the signal to the position portion of the feedback control loop. Additionally, the force load sensor can capture force data and convert it into a force signal 741, which can then transmit it to the force portion of the feedback control loop. The circuit can also include a high value selection circuit 744 that can select a high value after processing the position signal ( Figure 7 "KP" in) and force signal ( Figure 7The servo valve / hydraulic cylinder actuator selects between two references ("KF" in the figure) and transmits one of them to the servo valve. In some embodiments, the servo valve / hydraulic cylinder actuator can control either the force applied by the actuator or the position of the actuator. In some embodiments, the actuator may not be able to control both simultaneously. The high value selection circuit 744 allows the actuator to meet the needs of either the force or position controller, depending on the configuration of the high value selection circuit. In some embodiments, the high value selection circuit 744 selects the minimum of the two actuator references. For example, when the ironing roller assembly moves the ironing roller into contact with the web, the actuator's position reference is set to 50% of stroke, while the force reference is set to 1000 Newtons. Since the roller is not in contact with the web, the force controller output attempts to extend the hydraulic cylinder by requesting maximum pressure. The position controller requires less pressure to maintain the hydraulic cylinder in the contact stroke. The high value selection circuit 744 selects the smaller of the two, position and force. When the ironing roller contacts the web, the position reference switches to 100% stroke, thus requiring 100% pressure in some embodiments. The force controller may only require 25% of the pressure and be selected by the circuit.

[0046] The position and force data associated with the web and roller can be continuously captured and monitored and then fed back into the circuit. In other words, as the web rotates, the process is continuous and the encoder pulses generate updates to the model. The servo valve / hydraulic cylinder actuator is controlled by two different controllers - position and force. In the high value selection circuit 744, KP represents the position controller and KF represents the force controller. In some embodiments, depending on its requirements (e.g., output), only one controller controls the actuator at any given time. Because it is a feedback loop, the force controller may not be able to compensate for interference from bumps.

[0047] While the process of collecting and correlating data is performed on a continuous basis as described above, it can also be performed on a winding-by-winding basis (e.g., collect force and angular position data during a rotation, take some action, and repeat).

[0048] Although various circuit components are Figure 7 734, which may have previously captured data or signals from the take-up system (e.g., from a hydraulic cylinder).

[0049] Apart from Figure 6In addition to the components of the hydraulic cylinder system described above, the control system 700 may also include a reel encoder 744. The reel encoder 744 can be configured to determine the frequency of the web 701, which can be used as described below with respect to the force prediction circuit 750. The goal of the control strategy is to generate a set of force reference values ​​that, when added together, produce an actuator force that is of opposite polarity and equal or substantially equal amplitude to the bump disturbance. In some embodiments, the controller correlates the force applied by the ironing roller to the web surface with the angular position of the web. The encoder can then generate a signal corresponding to the angular position of the web. The control system 700 may also include a counter 752. For example, the counter 752 can be set to 120 pulses per revolution, thereby repeatedly counting from zero to 119. The counter 752 can correlate the position of the web with the sine and cosine components from the force prediction circuit 750, as described in more detail below. In other words, the counter 752 can indicate which portion of the web is being represented. For example, in one embodiment, assume that the encoder generates a series of continuous pulses at a rate of 120 pulses per revolution. Each time the counter accumulates 120 pulses from the encoder, it resets to zero. Each count in the counter then represents 3 degrees of rotation. The counter output is fed simultaneously into sine and cosine generators so that the sine and cosine frequencies match the frequency of the web's rotation. If the counter counts each encoder pulse twice, the sine and cosine signals will have a frequency twice that of the web, and so on. As each encoder pulse is counted, the measured force is correlated with the angular position of the web. The encoder and counter combination can be replaced by any device or combination of devices that generates a signal corresponding to the web's angular position.

[0050] As described above, the control system 700 may also include one or more force prediction circuits 750, each of which may include a counter 752, a sine function engine 754, a cosine function engine 756, and a least mean square (LMS) algorithm 758. In order to model the reduced force of the roller that can be used to counteract the web force count represented by the sine wave from the force prediction circuit 750 caused by the web protrusion, the frequency, amplitude, and phase shift of the sine wave at each harmonic can be determined. The reel encoder 744 may be used to measure and determine the frequency. For each force prediction circuit 750, in order to determine the amplitude and phase shift, a related control scheme (e.g., LMS algorithm 758) may be used. Using the LMS algorithm 758, the force feedback from the load transducer may be associated with the sine wave 754 and the cosine wave 756. At the adder 760, the outputs of the sine wave 754 and the cosine wave 756 may be added, and the output of the adder includes a signal representing force, the frequency, amplitude, and phase shift of the force representing the web force caused by the protrusion in the web.

[0051] The exemplary force prediction circuit 750 may be, for example, a self-tuning bandpass filter having these exemplary components. Figure 7 The control system 700 in FIG. 7 is shown as including only one force prediction circuit 750 , but as explained further below, the control system 700 may include any other number of force prediction circuits 750 .

[0052] As described herein, the hydraulic cylinder can be configured to cause the roller to generate a reduced force that is opposite in polarity to the force generated by the coil due to the protrusion in the coil and sufficient to maintain a consistent combination of forces between the roller and the coil throughout the winding process. The control system 700 can be configured to generate a signal representing a precisely calculated reaction force used by the hydraulic cylinder (e.g., via a servo valve) to generate the rolling force. In other words, this active system can provide the precise amount of energy required to radially move the ironing roller relative to the coil. To determine the force the roller should exert, the force of the protrusion can be determined and modeled. The protrusion in the coil can be modeled as one or more harmonics (i.e., component frequencies of a sine wave). Each component frequency can represent the frequency / angular velocity of the coil's rotation / rotation. The number of frequencies required for a given model, and therefore the number of force prediction circuits, can be adaptively determined based on the situation. For example, in some embodiments, the servo valve / cylinder actuator has a frequency limit. Let's assume the limit is found to be 45 Hz. As the winding operation begins, the angular frequency of the coil reaches a maximum, but decreases as the coil diameter increases. If the maximum frequency of the web is 15 Hz, only the first three harmonic filters will be used. If the fourth is used, the required actuator frequency will be 60 Hz. As the web decelerates, additional harmonics can be applied when its frequency drops below 50 Hz. Each of the five harmonics will be represented by a separate force prediction circuit 750, which can be as follows: Figure 8 8. As shown connected to each other (which shows three exemplary force prediction circuits 850, which represent three different harmonics).

[0053] In an ideal situation, to obtain a perfect protrusion model, the protrusion can be modeled as a set of an infinite number of harmonics. However, even if the model is represented as a set of more than one harmonic, such as two, three, four, five, six or more harmonics, a relatively accurate model for the protrusion can be provided (for example, using five harmonics to generate a model can provide a model accuracy of approximately 90% of that of a theoretically infinite number of harmonics). For example, a model can be generated using five harmonics. Of the five harmonics, one harmonic will represent the fundamental frequency (for example, N Hz) and the remaining four harmonics will be multiples of the fundamental frequency (2xN Hz, 3xN Hz, 4xN Hz, 5xN Hz, etc.). Since the speed of the coil may change frequently, the fundamental frequency and therefore all five frequencies may change frequently; the harmonics used always represent the current speed of the coil at a given time. Since the algorithm described in this article is event-based rather than time-based (for example, pulses from the encoder generate the actual code execution), changes in the mill speed may not affect performance.

[0054] Feedback control systems may inherently include phase delays. The controller output may be asynchronous with the web's angular position, necessitating a feedforward control component. For example, in some embodiments, the control signal is based on a model-based feedback, while the model itself is based on feedback. While the system relies on feedback to tune the model, it can generate an ironing roll force reference in anticipation of changes in web radius, as described herein.

[0055] Figure 9 is an exemplary flow chart of an exemplary process according to an embodiment of the present technology. Step 902 may include forming a portion of a coil from a metal strip, for example, by performing a coil forming operation using a coiling device, the portion comprising a first coil and a second coil, wherein the second coil includes a protrusion. The protrusion or bump may be caused by the leading edge of the first coil overlapping the leading edge of the second coil. The protrusion may be caused by the fact that the leading edge of the first coil has a non-zero height / thickness.

[0056] Step 904 may include capturing first coil data associated with the coil by a first sensor during a coil forming operation, for example, while the metal strip is being wound into a coil. The first coil data includes data corresponding to a radial force from the coil applied to the roller when the roller contacts the protrusion. The first sensor may include a load cell or other device configured to detect coil force and convert this data into a signal. The first coil data may include data corresponding to coil force caused, for example, by the protrusion and the roller contacting the protrusion. Step 906 may include capturing second coil data associated with the coil by a second sensor during a coil forming operation, for example, while the metal strip is being wound into a coil. The second coil data includes data corresponding to the position of the coil when the roller contacts the coil. The second sensor may include a linear transducer or other device configured to detect the position of the coil and convert this data into a signal. The second coil data may include data corresponding to the position of the coil. The coil position may include various specific data regarding the position of the coil at a specific time. In one example, the web position data may include the diameter of the web surface beneath the roller (eg, the height of the protrusion) at a particular time during the web forming operation.

[0057] Step 908 may include, for example, using the first coil data, the second coil data, and a circuit to determine a signal corresponding to the rolling force of the roller and the position of the protrusion. The circuit may be composed of one or more self-tuning bandpass filters. Each bandpass filter may be associated with a different harmonic of the coil speed, and a combination of filters may be used in combination to output a signal representing a rolling force opposite to the force of the coil, so that the combination of forces between the roller and the coil remains consistent throughout the coiling process. Step 910 may include, for example, transmitting a signal to a hydraulic cylinder coupled to the roller, wherein after the hydraulic cylinder receives the signal, the hydraulic cylinder causes the roller to apply a rolling force opposite to the radial force of the coil. After determining the opposing force, a signal representing the opposing force may be applied to the roller by the hydraulic cylinder, thereby achieving a substantially constant force throughout the coiling process.

[0058] The various aspects described above are merely examples of possible implementations, which are set forth solely for the purpose of clearly understanding the principles of the present disclosure. Many changes and modifications may be made to the examples described above without departing substantially from the spirit and principles of the present disclosure. All such modifications and changes are included herein within the scope of the present disclosure, and all possible claims regarding various aspects or combinations of elements or steps are intended to be supported by the present disclosure. In addition, although specific terms are employed herein and in the claims that follow, the terms are used only in a general and descriptive sense and are not intended to limit the invention described or the claims that follow.

[0059] In the context of describing the present invention (especially in the context of the following claims), the terms "one" and "a kind of" and "said" and similar references should be interpreted as covering both the singular and the plural, unless otherwise indicated herein or clearly contradicted by the context. The terms "comprising", "having", "including" and "containing" should be interpreted as open-ended terms (i.e., meaning "including but not limited to"), unless otherwise noted. The term "connected" should be interpreted as being partially or completely included in the following explanation: attached to or combined together, even if there are middleware. Unless otherwise indicated herein, the enumeration of value ranges herein is merely intended to be used as a shorthand method to individually represent each individual value belonging to the range, and each individual value is incorporated into this specification as if individually described herein. Unless otherwise indicated herein or otherwise clearly contradicted by the context, all methods described herein can be performed in any appropriate order. The use of any and all examples or exemplary language (e.g., "such as") provided herein is intended only to better illustrate embodiments of the present invention, and unless otherwise required, will not impose limitations on the scope of the present invention. The language in this specification should not be interpreted as indicating any non-required element as necessary for practicing the present invention.

[0060] The following provides a collection of exemplary examples, including at least some explicitly listed "ECs (Exemplary Combinations)", which provide additional descriptions of various exemplary types according to the concepts described herein. These examples are not meant to be mutually exclusive, exhaustive, or limiting; and the present invention is not limited to these exemplary examples, but rather encompasses all possible modifications and variations within the scope of the claims set forth and their equivalents.

[0061] EC 1. A method comprising: forming a portion of a coil from a metal strip by performing a coil forming operation using a coiling apparatus, the portion comprising a first coil and a second coil, wherein the second coil comprises a protrusion; while coiling the metal strip into the coil, capturing, by a first sensor, first coil data associated with the coil during the coil forming operation, wherein the first coil data comprises data corresponding to a radial force from the coil applied to a roller when the roller contacts the protrusion; while coiling the metal strip into the coil, capturing, by a second sensor, second coil data associated with the coil during the coil forming operation, wherein the second coil data comprises data corresponding to a position of the coil when the roller contacts the coil; determining, using the first coil data, the second coil data, and circuitry, a signal corresponding to a rolling force of the roller and a position of the protrusion; and transmitting the signal to a hydraulic cylinder coupled to the roller, wherein upon receipt of the signal by the hydraulic cylinder, the hydraulic cylinder causes the roller to apply a rolling force, wherein the rolling force opposes the radial force of the coil.

[0062] EC 2. The method of any combination of the preceding or following examples, wherein the hydraulic cylinder causing the roller to apply the rolling force includes reducing the force applied by the roller.

[0063] EC 3. The method of any combination of the preceding or following examples, further comprising determining data corresponding to a frequency of the web over a period of time using a spool encoder electrically connected to the web.

[0064] EC 4. The method of any preceding or following combination of examples, wherein the circuit comprises a bank of self-tuning bandpass filters.

[0065] EC 5. The method of any combination of the preceding or following examples, wherein each filter in the set of self-tuning bandpass filters is associated with a harmonic of the angular velocity of the web.

[0066] EC 6. The method of any combination of the preceding or following examples, wherein the protrusion in the second turn of the web is at least partially formed by a leading edge of the first turn of the web.

[0067] EC 7. The method of any combination of the preceding or following examples, wherein the second web data comprises data corresponding to a position of the web when the roller contacts the protrusion.

[0068] EC 8. The method of any preceding or following example combination, wherein the first sensor is a load cell electrically connected to the roller.

[0069] EC 9. The method of any one of the preceding or following example combinations, wherein the second sensor is a linear transducer electrically connected to the hydraulic cylinder.

[0070] EC 10. The method of any preceding or following combination of examples, wherein the roller is an ironing roller.

[0071] EC 11. A system comprising: a roller configured to contact a surface of a web, wherein the web is formed by performing a web-forming operation using a winding device; a load cell configured to capture first data corresponding to a first force transmitted by the web in one direction; a linear transducer configured to capture second data corresponding to a position of the web; a circuit configured to use the first data and the second data to determine a signal associated with a second force for counteracting the first force; and a hydraulic cylinder configured to receive the signal from the circuit and transmit the second force to the roller in a second direction opposite to the first direction.

[0072] EC 12. The system of any combination of the preceding or following examples, wherein the hydraulic cylinder causing the roller to apply the rolling force includes reducing the force applied by the roller.

[0073] EC 13. The system of any preceding or following example combination, further comprising a spool encoder electrically connected to the web, wherein the spool encoder is configured to generate data corresponding to a frequency of the web over a period of time.

[0074] EC 14. The system of any preceding or following combination of examples, wherein the circuit comprises a set of self-tuning bandpass filters.

[0075] EC 15. The system of any preceding or following combination of examples, wherein each filter in the set of self-tuning bandpass filters is associated with a harmonic of the angular velocity of the web.

[0076] EC 16. The system of any preceding or subsequent example combination, wherein the portion of the coil comprises a first coil and a second coil formed from a metal strip, wherein the second coil comprises a protrusion, wherein the protrusion in the second coil is at least partially formed by a leading edge of the first coil.

[0077] EC 17. The system of any combination of the preceding or following examples, wherein the second web data comprises data corresponding to a position of the web when the roller contacts the protrusion.

[0078] EC 18. The system of any combination of the preceding or following examples, wherein the load cell is electrically connected to the roller.

[0079] EC 19. The system of any preceding or following combination of examples, wherein the linear transducer is electrically connected to the hydraulic cylinder.

[0080] EC 20. The system of any preceding or following combination of examples, further comprising the roller being an ironing roller.

[0081] Preferred embodiments of the present invention are described herein, including the best mode of implementing the present invention known to the inventor. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art after reading the foregoing description. The inventors expect that the skilled person will adopt such variations as appropriate, and the inventors intend to practice the present invention in a manner different from that specifically described herein. Therefore, as long as the law permits, the present invention includes all modifications and equivalents of the subject matter recited in the appended claims. In addition, unless otherwise indicated herein or clearly contradicted by the context, the present invention encompasses any combination of the above elements in all possible variations thereof.

[0082] All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

Claims

1. A method for maintaining a constant force between a roller and a coil during a coil forming operation, comprising: forming a portion of the coil from the metal strip by performing a coil forming operation using a coiling apparatus, the portion comprising a first coil and a second coil, wherein the second coil comprises a protrusion; capturing, by a first sensor, first coil data associated with the coil during the coil forming operation while the metal strip is being wound into the coil, wherein the first coil data includes data corresponding to a radial force from the coil applied to the roller when the roller contacts the protrusion; while winding the metal strip into the coil, capturing, by a second sensor, second coil data associated with the coil during the coil forming operation, wherein the second coil data includes data corresponding to a position of the coil when the roller contacts the coil; determining a signal corresponding to a rolling force of the roller and a position of the protrusion using the first web data, the second web data, and circuitry; as well as transmitting the signal to a hydraulic cylinder coupled to the roller, wherein after the hydraulic cylinder receives the signal, the hydraulic cylinder causes the roller to apply the rolling force, wherein the rolling force is opposite to the radial force of the web, adjusting the rollers so that the combination of the rolling force and the radial force of the coil is constant throughout the coiling process, The circuit includes a set of self-tuning bandpass filters, wherein each filter in the set of self-tuning bandpass filters is associated with a harmonic of the angular velocity of the web. 2 . The method of claim 1 , wherein the hydraulic cylinder causing the roller to apply the rolling force comprises reducing the force applied by the roller.

3. The method of claim 1 , further comprising: Data corresponding to the frequency of the web over a period of time is determined using a spool encoder electrically connected to the web.

4. The method of claim 1, wherein the protrusion in the second coil is formed at least in part by a leading edge of the first coil.

5. The method of claim 1, wherein the second web data includes data corresponding to a position of the web when the roller contacts the protrusion.

6. The method of claim 1, wherein the first sensor is a load cell electrically connected to the roller.

7. The method of claim 1, wherein the second sensor is a linear transducer electrically connected to the hydraulic cylinder.

8. The method of claim 1, wherein the roller is an ironing roller.

9. A system for maintaining a constant force between a roller and a web during a web forming operation, comprising: a roller configured to contact a surface of a web, wherein the web is formed by a web-forming operation using a coiling apparatus; a load cell configured to capture first data corresponding to a first force transmitted by the web in a first direction; a linear transducer configured to capture second data corresponding to a position of the web; circuitry configured to use the first data and the second data to determine a signal associated with a second force for counteracting the first force; as well as a hydraulic cylinder configured to receive the signal from the circuit and transmit the second force to the roller in a second direction opposite to the first direction, wherein the system is configured to adjust the rollers so that the combination of forces is constant throughout the winding process, The circuit includes a set of self-tuning bandpass filters, wherein each filter in the set of self-tuning bandpass filters is associated with a harmonic of the angular velocity of the web.

10. The system of claim 9, wherein the hydraulic cylinder causing the roller to apply a rolling force includes reducing the force applied by the roller.

11. The system of claim 9, further comprising a spool encoder electrically connected to the web, wherein the spool encoder is configured to generate data corresponding to a frequency of the web over a period of time.

12. The system of claim 9, wherein the portion of the coil comprises a first coil and a second coil formed from a metal strip, wherein the second coil comprises a protrusion, wherein the protrusion in the second coil is formed at least in part by a leading edge of the first coil.

13. The system of claim 12, wherein the second web data includes data corresponding to a position of the web when the roller contacts the protrusion.

14. The system of claim 9, wherein the load cell is electrically connected to the roller.

15. The system of claim 9, wherein the linear transducer is electrically connected to the hydraulic cylinder.

16. The system of claim 9, wherein the roller is an ironing roller.

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