JP7149861B2 - Conveyor control method - Google Patents

Description

TECHNICAL FIELD The present disclosure relates to a method of controlling a transport device.

In order to prevent out-of-plane deformation of the plate material and smoothly convey the plate material in the production line of the plate material, a pinch roll device is used that pinches the plate material with a pair of upper and lower pinch rolls and conveys the plate material while applying tension to the plate material. (See Patent Document 1, for example).

JP-A-8-108208

In the apparatus for transporting the plate material as described above, the center position of the plate width of the plate material may deviate from the center of the transport line when the plate material is transported. In the present disclosure, this phenomenon will be referred to as "meandering of the plate material". In the worst case, a part of the plate material may be pushed out from the pinch roll body and the plate material may be damaged.

The present disclosure has been made in view of the above situation, and particularly in a plate material conveying device in which a plurality of pinch roll devices are arranged in series on a conveying line, the plate width center position of the plate material can be satisfactorily controlled to the plate width center target position. intended to

The present inventors have made intensive studies on a conveying device capable of suppressing meandering of a plate material and a method of controlling the conveying device. The present inventors first measured the load at each end in the axial direction of the pinch roll, assumed that the plate material was meandering on the side where the load was large, and relatively tightened the roll-down position on the side where the load was large. It was thought that the configuration of the prior art, in which the sheet material is relieved to the side where the load is smaller and the meandering is improved, is effective by implementing the directional roll-down position control. However, even when the roll-down position control is performed, there are cases where the plate material cannot escape to the side where the load is smaller, and meandering cannot be sufficiently improved.

Therefore, as a result of extensive studies, the inventors of the present invention have found that when the pinch roll device applies a braking force in the conveying direction to the plate material and the exit side tension is greater than the entry side tension, the meandering of the plate material can be prevented by the above-described conventional technology. However, in the opposite case, that is, when the pinch roll device applies a driving force in the conveying direction to the plate material and the entry side tension is greater than the exit side tension, the meandering of the plate material will By controlling the roll-down position in the direction opposite to that of the conventional technology, i.e., by operating the roll-down position on the side where the plate meanders in the direction of opening relatively, the meandering can be suppressed, and the pinch roll device is effective against the plate. It has been found that when the tension on the entry side and the tension on the exit side are substantially equal without giving any driving force or braking force, the meandering behavior of the plate material cannot be effectively controlled even if the roll position is controlled. Based on this discovery, the present inventors have solved the problems of the prior art, and have found a control method for a device that conveys a plate while controlling the plate width center position of the plate to a target value.

In one aspect of the method for controlling a conveying device according to the present disclosure, a pair of upper and lower pinch rolls for conveying a plate material, a driving device for driving the pinch rolls, and at least one of the upper and lower pinch rolls at both ends in the axial direction A conveying device having a plurality of pinch roll devices in series, each of which has a roll-down device that rolls down a pinch roll and a load measuring device that measures the load at each of the axial ends of at least one of the upper and lower pinch rolls, wherein the pinch rolls At least one device applies a driving force to the plate material in the conveying direction, and at least another device applies a braking force to the plate material in a direction opposite to the conveying direction.

Further, in one aspect of the method for controlling a conveying device according to the present disclosure, a pair of upper and lower pinch rolls for conveying a plate material, a driving device for driving the pinch rolls, and both axial ends of at least one of the upper and lower pinch rolls A plurality of pinch roll devices in series on the same line, each of which has a roll-down device that rolls down the pinch roll and a load measuring device that measures the load at each of the axial ends of at least one of the upper and lower pinch rolls, At least one of the pinch roll devices applies a driving force in the conveying direction to the plate, and at least another one of the pinch roll devices applies a braking force to the plate in a direction opposite to the conveying direction. , the present value of the plate width center position of the plate material pinched by each pinch roll device is detected, and the present value of the plate width center position is aimed to approach the target value of the plate width center position, and the pinch rolls In a pinch roll device that applies a driving force in the conveying direction to a plate material, the distribution of the load acting between the plate material and the pinch roll in the plate width direction is determined based on the plate width center position current value. The pressure reduction devices on the working side and the drive side of the pinch roll device are operated in a direction to make the load on the position target value side relatively larger than the other, and the pinch rolls are applied to the plate material in a direction opposite to the conveying direction. In the pinch roll device to which power is applied, the load on the side of the target width center position is calculated based on the current width center position with respect to the distribution of the load acting between the strip and the pinch roll in the width direction. The screw down devices on the working side and the drive side of the pinch roll device are operated in a direction to make one relatively smaller than the other.

Further, in one aspect of the method for controlling a conveying device according to the present disclosure, a pair of upper and lower pinch rolls for conveying a plate material, a driving device for driving the pinch rolls, and both axial ends of at least one of the upper and lower pinch rolls A plate material having a plurality of pinch roll devices in series on the same line, which are equipped with a rolling device that rolls down the pinch roll and a load measuring device that measures the load at each of the axial ends of at least one of the upper and lower pinch rolls. A control method for a conveying device, wherein when the leading end of the plate material is passed, the most downstream side grips the leading end of the plate each time the leading end of the plate is caught in a pinch roll device arranged downstream. The leading edge of the plate material is adjusted so that the driving force applied to the plate material from the side pinch roll device is significantly different from the driving force applied when the leading edge of the plate member bites into the adjacent upstream pinch roll device. to control the electric motor torque of the drive device of the pinch roll device on the most downstream side.

Further, in one aspect of the method for controlling a conveying device according to the present disclosure, a pair of upper and lower pinch rolls for conveying a plate material, a driving device for driving the pinch rolls, and both axial ends of at least one of the upper and lower pinch rolls A plate material having a plurality of pinch roll devices in series on the same line, which are equipped with a rolling device that rolls down the pinch roll and a load measuring device that measures the load at each of the axial ends of at least one of the upper and lower pinch rolls. A control method for a conveying device, which acts on a plate existing between pinch roll devices on the upstream side of a pinch roll device on the most downstream side gripping the leading end of the plate when the leading end of the plate is passed. The motor torque of the upstream pinch roll drive is controlled so that the tension does not change over time.

Further, in one aspect of the method for controlling a conveying device according to the present disclosure, a pair of upper and lower pinch rolls for conveying a plate material, a driving device for driving the pinch rolls, and both axial ends of at least one of the upper and lower pinch rolls A plate material having a plurality of pinch roll devices in series on the same line, which are equipped with a rolling device that rolls down the pinch roll and a load measuring device that measures the load at each of the axial ends of at least one of the upper and lower pinch rolls. A method for controlling a conveying device, in which the trailing end of the plate is gripped every time the trailing end of the plate passes through a pinch roll device arranged on the upstream side when the trailing end of the plate is passed. The electric motor torque of the driving device of the most upstream pinch roll device is increased so as not to change the tension acting on the plate material existing between the most upstream pinch roll device and the adjacent downstream pinch roll device with time. Control.

Further, in one aspect of the method for controlling a conveying device according to the present disclosure, a pair of upper and lower pinch rolls for conveying a plate material, a driving device for driving the pinch rolls, and both axial ends of at least one of the upper and lower pinch rolls A plate material having a plurality of pinch roll devices in series on the same line, which are equipped with a rolling device that rolls down the pinch roll and a load measuring device that measures the load at each of the axial ends of at least one of the upper and lower pinch rolls. A control method for a conveying device, wherein when the leading end of the plate material is passed, the most downstream side grips the leading end of the plate each time the leading end of the plate is caught in a pinch roll device arranged downstream. The pressing device of the pinch roll device located upstream from the side pinch roll device and gripping the plate material is operated to release the pressing force, and at the same time, the tension acting on the plate material at the position where the pressing force is released is released. to maintain the motor torque of the drive of the most downstream pinch roll device.

Further, in one aspect of the method for controlling a conveying device according to the present disclosure, a pair of upper and lower pinch rolls for conveying a plate material, a driving device for driving the pinch rolls, and both axial ends of at least one of the upper and lower pinch rolls A plate material having a plurality of pinch roll devices in series on the same line, which are equipped with a rolling device that rolls down the pinch roll and a load measuring device that measures the load at each of the axial ends of at least one of the upper and lower pinch rolls. A method for controlling a conveying device, wherein when the trailing end of the plate material is threaded, each time the trailing end of the plate material passes through a pinch roll device arranged on the upstream side and the rolling force is released, Of the pinch roll devices that are arranged downstream from the most upstream pinch roll that grips the tail end of the plate material and are on standby with the rolling force released, the plate material is gripped by the most upstream pinch roll device and a predetermined At the same time, the electric motor torque of the driving device of the pinch roll device is controlled so as to maintain the tension of the plate material downstream from the pinch roll device. .

According to the present disclosure, in conveying a plate material using a conveying device in which a plurality of pinch roll devices are arranged in series, the tension acting on the plate material is controlled within a predetermined range, and the shape of the plate material is not deteriorated. The center position of the width of the strip can be well controlled to the target value, and stable strip threading can be realized.

FIG. 4 is a diagram illustrating an outline of a control method for a plate material conveying device according to the present disclosure; FIG. 4 is a diagram illustrating an outline of a control method for a plate material conveying device according to the present disclosure; FIG. 3 is a diagram showing an outline of a control method for a plate material conveying device according to the present disclosure; FIG. 4 is a diagram illustrating an outline of a control method for a plate material conveying device according to the present disclosure; 1 is a diagram showing a schematic configuration of a pinch roll device according to the present disclosure; FIG. 4 is a flow chart showing an outline of a control method for a plate material conveying device according to the present disclosure; The figure which shows the positional relationship of a pinch roll and a board|plate material. FIG. 10 is a diagram showing the target value of the load distribution between the plate material and the pinch rolls and the load application point position when the plate material is closer to the work side under the condition that the pinch rolls apply a driving force in the conveying direction to the plate material. FIG. 10 is a diagram showing the target value of the load distribution between the plate material and the pinch rolls and the position of the load application point when the plate material is closer to the drive side under the condition that the pinch rolls apply a driving force in the conveying direction to the plate material. A diagram showing the load distribution between the plate and pinch rolls and the target value of the load application point position when the plate is on the work side under the condition that the pinch rolls apply a braking force to the plate in the direction opposite to the conveying direction. is. A diagram showing the load distribution between the plate and pinch rolls and the target value of the load application point position when the plate is on the drive side under the condition that the pinch rolls apply a braking force to the plate in the direction opposite to the conveying direction. is. FIG. 5 is a diagram showing the relationship between work-side and drive-side load measurements and plate position; FIG. 4 is a diagram schematically showing a control method of a sheet material conveying apparatus of the present disclosure when a sheet material leading edge portion is threaded, for a run-out table of a thin sheet hot rolling facility having a plurality of pinch roll devices. FIG. 4 is a diagram schematically showing a control method of a sheet material conveying apparatus of the present disclosure in the process of introducing a winding machine for the leading edge of a sheet material, for a runout table of a thin sheet hot rolling facility having a plurality of pinch roll devices. FIG. 4 is a diagram schematically showing a control method of the sheet material conveying apparatus of the present disclosure during sheet material tail end threading for a runout table of a thin sheet hot rolling facility having a plurality of pinch roll devices. FIG. 4 is a diagram schematically showing a control method of a sheet material conveying apparatus of the present disclosure when a sheet material leading edge portion is threaded, for a run-out table of a thin sheet hot rolling facility having a plurality of pinch roll devices. FIG. 4 is a diagram schematically showing a control method of a sheet material conveying apparatus of the present disclosure in the process of introducing a winding machine for the leading edge of a sheet material, for a runout table of a thin sheet hot rolling facility having a plurality of pinch roll devices. FIG. 4 is a diagram schematically showing a control method of the sheet material conveying apparatus of the present disclosure during sheet material tail end threading for a runout table of a thin sheet hot rolling facility having a plurality of pinch roll devices. FIG. 4 is a diagram schematically showing a control method of a sheet material conveying apparatus of the present disclosure when a sheet material leading edge portion is threaded, for a run-out table of a thin sheet hot rolling facility having a plurality of pinch roll devices. FIG. 4 is a diagram schematically showing a control method of a sheet material conveying apparatus of the present disclosure in the process of introducing a winding machine for the leading edge of a sheet material, for a runout table of a thin sheet hot rolling facility having a plurality of pinch roll devices. FIG. 4 is a diagram schematically showing a control method of the sheet material conveying apparatus of the present disclosure during sheet material tail end threading for a runout table of a thin sheet hot rolling facility having a plurality of pinch roll devices. FIG. 10 is a diagram schematically showing the force in the conveying direction applied to the plate material in the vicinity of pinch rolls when the tension on the entry side is greater than the tension on the exit side. FIG. 10 is a diagram showing the lateral difference in conveying direction force and the moment applied to the plate material when the tension on the entry side is greater than the tension on the exit side and the pinch rolls pinch the work side of the plate material more strongly than the drive side. FIG. 5 is a diagram schematically showing the force in the conveying direction applied to the plate in the vicinity of pinch rolls when the tension on the entry side is smaller than the tension on the exit side. FIG. 10 is a diagram showing the lateral difference in conveying direction force and the moment applied to the plate material when the tension on the entry side is smaller than the tension on the exit side and the pinch rolls pinch the work side of the plate material more strongly than the drive side. In comparison with FIG. 13, which shows an outline of the control method of the sheet material conveying device of the present disclosure when the sheet material leading end portion is passed, targeting the run-out table of the thin sheet hot rolling equipment in which a plurality of pinch roll devices are arranged, it is not preferable. FIG. 4 is a diagram showing an embodiment;

Hereinafter, embodiments will be described in detail with reference to the drawings. In the description, the same reference numerals are given to the same elements or elements having the same function, and overlapping descriptions are omitted.

First, with reference to FIG. 5, an outline of a plate material pinch roll device 100 according to the present disclosure will be described. The pinch roll device 100 is a device that transports the plate material 2 in a predetermined transport direction while pinching the plate material 2 between a pair of upper and lower pinch rolls 1a and 1b in a manufacturing/processing line for the plate material 2. As shown in FIG. A plate material pinch roll device 100 includes pinch rolls 1a and 1b, rolling devices 3a and 3b, and load measuring devices 4a and 4b. The pinch rolls 1a, 1b are configured to be driven by an electric motor 6 via spindles 7a, 7b and a pinion stand 8. In the present disclosure, the spindles 7a, 7b, pinion stand 8, electric motor 6, and A control device for the electric motor 6 that is not connected is collectively referred to as a drive device. Furthermore, the pinch roll device 100 of FIG. 5 is provided with a plate edge position measuring device 5 for measuring the plate edge position on the work side of the plate material as an example of the embodiments of the present disclosure.

The pinch rolls 1a and 1b are rotating bodies that pinch the plate material 2 from above and below with a predetermined pressure and transport the plate material 2 in a predetermined transport direction. One axial end (working side) of the upper pinch roll 1a is connected to the screw down device 3a via a chock, and the other axial end (driving side) is connected to the screw down device 3b via a chock. ing. The working side of the lower pinch roll 1b is connected to the load measuring device 4a via a chock, and the driving side is connected to the load measuring device 4b via a chock.

The pressing devices 3a and 3b press down the pinch roll 1a on the working side and the driving side (both ends in the axial direction) of the pinch roll 1a, respectively. The roll-down device 3a rolls down the working side of the pinch roll 1a at a set pinch-roll roll-down position. The roll-down device 3b rolls down the driving side of the pinch roll 1a at a set pinch-roll roll-down position.

The load measuring devices 4a, 4b measure loads on the working side and the driving side of the pinch roll 1b, respectively. The load measuring device 4a measures the load on the working side of the pinch roll 1b. The load measuring device 4b measures the load on the driving side of the pinch roll 1b.

The electric motor 6 applies a predetermined driving torque or braking torque to the pinch rolls 1a and 1b through the pinion stand 8 and the spindles 7a and 7b, thereby applying a predetermined tension to the plate material.

The plate edge position measuring device 5 continuously (always) measures the plate edge positions of the plate 2 being conveyed by the pinch rolls 1a and 1b. The plate edge position measuring device 5 is fixed at a predetermined position near the pinch roll device 100, for example, and determines the plate material 2 being conveyed from the detected plate edge position and the known plate width of the plate material 2. Deriving the strip width center position of Alternatively, when the plate width of the plate 2 is not known, the plate edge position measuring device 5 may derive the plate width center position of the plate 2 by measuring both end positions of the plate 2 in the plate material width direction. The position measurement method by the plate edge position measuring device 5 is not limited, and known sensors such as photomicrosensors, area sensors, photoelectric sensors, proximity sensors, fiber sensors, or laser sensors can be used. can.

Next, with reference to FIG. 1, one aspect of the control method of the conveying apparatus of the present disclosure will be described in detail. FIG. 1 illustrates a control method in a conveying device having two pinch roll devices. In FIG. 1(a), of the two pinch roll devices, the #1 pinch roll device located on the upstream side with respect to the conveying direction 11 of the sheet material has a motor torque of αT, and the #2 pinch roll located on the downstream side is given by αT. The motor torque of the device is assumed to be -αT. Here, T (>0) is the motor torque of the pinch roll device that applies tension σ (>0) to the plate, and α is a constant in the range of 0<α<1. When the motor torque is positive, the pinch roll device applies a driving force to the plate material in the conveying direction. will give. In FIG. 1(a), the entry-side tension of the #1 pinch roll device is controlled to σ by equipment (not shown) such as a bridle roll, and the motor torque of the #1 pinch roll device is α T, so The exit side tension of the #1 pinch roll device becomes (1-α)σ smaller than the entry side tension by α·σ. Furthermore, in FIG. 1(a), the motor torque of the #2 pinch roll device is -α T, and the braking force is applied, so the tension on the exit side of the #2 pinch roll device is higher than the tension on the entry side by α σ. σ, that is, the same tension as the #1 pinch roll device entry side tension.

In FIG. 1(a), if the motor torque of the #2 pinch roll device is the same αT driving force as that of the #1 pinch roll device, the exit side tension of the #2 pinch roll device is (1-2α)σ. Become. In this case, the tension on the delivery side of the #2 pinch roll device becomes much smaller than σ, increasing the risk of unstable strip threading. If α exceeds 0.5, the exit side tension of the #2 pinch roll device becomes a negative value, i.e., a compressive force. board becomes impossible. From the above, based on the above-described discovery by the present inventors that it is necessary to apply a significant driving force or braking force to the pinch roll device in order to implement effective roll position control that suppresses meandering of the plate, In order to keep the tension of the plate material within a certain range where stable plate threading is possible, as shown in FIG. It is necessary to control the plate so as to apply a braking force in the direction opposite to the conveying direction.

In FIG. 1(b), contrary to FIG. 1(a), the motor torque of the #1 pinch roll device is −α·T, and the motor torque of the #2 pinch roll device is α·T. As a result, the tension between the #1 pinch roll device and the #2 pinch roll device is (1 + α) σ, but the #2 pinch roll exit side tension is the same σ as the #1 pinch roll entry side tension, and the tension of the plate material From the point of view, stable strip threading becomes possible.

In FIG. 1(b), if the motor torque of the #2 pinch roll device is set to the same braking force of -αT as that of the #1 pinch roll device, the exit side tension of the #2 pinch roll device is (1+2α)σ. . In this case, when the value of α is relatively large, the #2 pinch roll device delivery side tension becomes significantly larger than σ, and the risk of breakage of the plate increases. In order to effectively control meandering in the pinch roll device, the pinch roll device needs to apply a sufficient driving force or braking force, so a large value of α is preferable.

In the embodiment of FIG. 2(a), the motor torque of the #1 pinch roll device is α·T, and the motor torque of the #2 pinch roll device is −β·T. Here, β is a constant in the range of 0<β<1, like α. As a result, in the embodiment of FIG. 2(a), the tension on the delivery side of the #2 pinch roll device is (1-α+β)σ, and the tension level is kept within a certain range according to the value of β. It is possible to control the tension to be different from the #1 pinch roll entry side tension as desired.

In the embodiment of FIG. 2(b), the motor torque of the #1 pinch roll device is -α·T, and the motor torque of the #2 pinch roll device is β·T. As a result, in the embodiment of FIG. 2(b), the tension on the delivery side of the #2 pinch roll device is (1+α−β)σ. It is possible to control the tension to be different from the #1 pinch roll entry side tension so as to be suitable for sheet material processing.

FIG. 3 shows an embodiment of the control method of the present disclosure in a transport apparatus having more pinch roll devices, namely n pinch roll devices. In FIG. 3(a), #1 pinch roll device and #2 pinch roll device give the same motor torque as in FIG. controlled as follows. As a result, the tension of the plate becomes a repetition of two levels of σ and (1-α)σ, and even if many pinch roll devices are arranged, the tension level does not become abnormal, and a good meandering control function is achieved. This makes it possible to stably thread the strip.

In FIG. 3(b), #1 pinch roll device and #2 pinch roll device give the same motor torque as in FIG. controlled. As a result, the tension of the sheet material becomes a repetition of two levels of σ and (1 + α)σ, and even if many pinch roll devices are installed, the tension level does not become abnormal, and stable sheet threading is possible. Become.

FIG. 3(c) shows an embodiment in which, unlike FIG. 3(a), the same motor torque is applied to two pinch roll devices in series. In other words, the motor torque of the #1 pinch roll device is α T, but the motor torque of the #2 pinch roll device and #3 pinch roll device is −α T, and the motor torque of the #4 pinch roll device and #5 pinch roll device The torque is α·T, and thereafter, motor torque control is performed with that repeated pattern up to #n pinch rolls. As a result, the tension of the plate becomes a repeating pattern of σ, (1−α)σ, σ, (1+α)σ, and in this case also, the tension level becomes abnormal even if many pinch roll devices are arranged. Therefore, it is possible to stably thread the strip.

FIG. 3(d) is an embodiment in which the same electric motor torque is applied to two consecutive pinch roll devices as in FIG. 3(c), but the sign of the electric motor torque is reversed from that in FIG. It is a pattern. That is, the motor torque of the #1 pinch roll device is -αT, but the motor torque of the #2 pinch roll device and #3 pinch roll device is αT, and the motor torque of the #4 pinch roll device and #5 pinch roll device The torque is -α·T, and the motor torque control is carried out with that repeated pattern up to #n pinch rolls. As a result, the tension of the plate becomes a repeating pattern of σ, (1+α)σ, σ, (1-α)σ, and in this case also, the tension level becomes abnormal even if many pinch roll devices are arranged. Therefore, it is possible to stably thread the strip.

FIG. 3(e) shows an embodiment of a conveying device in which a pinch roll device with zero motor torque is mixed. The motor torque of the #1 pinch roll device is -αT, but the motor torque of the #2 pinch roll device and the #3 pinch roll device is 0, the motor torque of the #4 pinch roll device is αT, and the #5 pinch roll device The electric motor torque of the roll device is −α·T, and the electric motor torque control is performed in the same pattern as in FIG. 3B until the #n pinch roll. As a result, the tension of the plate material between the #1 pinch roll device and the #4 pinch roll device is (1 + α)σ, and the tension after the #4 pinch roll is a repetition of the pattern of σ, (1 + α)σ, and in this case also , the tension level does not become abnormal even if many pinch roll devices are arranged. In addition, although the #2 pinch roll device and the #3 pinch roll device themselves with a motor torque of 0 cannot implement effective meandering control, the #1 pinch roll device on the upstream side and the #4 pinch roll device on the downstream side Since effective meandering control can be performed, the conveying apparatus as a whole can stably thread the sheet.

したがってα_ｉ＝β_ｉ≡αであれば図３（ａ）と同じ張力状態となるが、例えば、α_ｉ＜β_ｉであれば下流側で次第に張力が大きくなる。このような張力分布は、例えば、板材の温度が、上流が高く、下流が低くなるようなプロセスに対しては、下流側の方が板材の変形抵抗が高くなるため好適となる場合が多い。逆に、α_ｉ＞β_ｉとすれば下流側で次第に張力を小さくすることもできる。なお、この実施態様では、α_ｉ、β_ｉの値をｉの値に応じて変更することによって、種々の張力パターンを得ることができ、板材の加熱、冷却、表面処理等の種々の処理装置の配置に応じて最適な張力状態を実現しつつ、有効な蛇行制御実施し、安定通板を実現することが可能となる。 FIG. 4 shows an embodiment in which the tension level of the plate can be graded from upstream to downstream of the conveying line. The conveying device of FIG. 4(a) has 2n pinch rolls, and for any integer i of 1≦i≦n, #(2i−1) the electric motor torque of the pinch roll device is α _i T( 0<α _i <1), and the motor torque of the #2i pinch roll device is −β _i ·T (0<β _i <1). As a result, the exit side tension σ _2i of the #2i pinch roll device is expressed by the following equation.

Therefore, if α _i =β _i ≡α, the tension state is the same as in FIG. 3A, but if α _i <β _i , the tension gradually increases on the downstream side. Such a tension distribution is often suitable for a process in which, for example, the temperature of the plate material is high upstream and low downstream, because the deformation resistance of the plate material is higher on the downstream side. Conversely, if α _i >β _i , the tension can be gradually reduced on the downstream side. In this embodiment, by changing the values of α _i and β _i according to the value of i, various tension patterns can be obtained, and various processing equipment such as heating, cooling, and surface treatment of plate materials can be obtained. While realizing the optimum tension state according to the arrangement of the , it is possible to implement effective meandering control and realize stable strip threading.

したがって図４（ｂ）の実施態様は図４（ａ）の実施態様に比べて、α_ｉ、β_ｉの符号を反転したものとなっており、＃（２ｉ－１）ピンチロール装置出側張力が入側張力に比べて高く設定されることが特徴となっている。 The conveying device in FIG. 4(b) has 2n pinch rolls, and for any integer i of 1≦ _i ≦n, #(2i−1) the electric motor torque of the pinch roll device is −α iT (0<α _i <1), and the motor torque of the #2i pinch roll device is β _i ·T (0<β _i <1). As a result, the exit side tension σ _2i of the #2i pinch roll device is expressed by the following equation.

Therefore, in the embodiment of FIG. 4(b), the signs of α _i and β _i are reversed compared to the embodiment of FIG. is set higher than the entry-side tension.

なお板幅の値が不確定な場合は駆動側にも板端位置測定装置を配し、駆動側板端位置ｚ_Ｄを実測して、作業側板端位置ｚ_Ｗと駆動側板端位置ｚ_Ｄの平均値として板幅中心位置現在値ｚ_Ｃを算出する。板幅中心位置現在値は厳密にはピンチロール直下の板幅中心位置であることが好ましいが、板端位置測定装置５が搬送装置に十分近ければ上記計算値ｚ_Ｃを板幅中心位置現在値とみなしてよい。さらに正確さを期する場合、搬送装置の入側と出側双方に板端位置測定装置を配備し、それぞれの実測値から計算される板幅中心位置ｚ_Ｃの平均をとって板幅中心位置現在値とすることが好ましい。本開示では以上のように実測値から演算によって板幅中心位置現在値を得ることを“板幅中心位置現在値を検出”と表現している。 Next, with reference to FIG. 6, an embodiment of the method for controlling the screw down device of the pinch roll apparatus of the present disclosure will be described in detail. First, the strip width center position current value is detected. When the device 5 capable of continuously measuring the strip edge position as shown in FIG. 5 is arranged in the vicinity of the conveying device, the strip width center position current value is calculated from this measured value and the known strip width. For example, as shown in FIG. 5, the position is indicated by defining the coordinate z with the line center as the origin and the work side being positive along the pinch roll axis. When the measured strip edge position on the working side is z _W and the known strip width is b, the strip edge position on the drive side is estimated by z _W - b, so the strip width center position current value z _C is the average of these The value is calculated by the following formula.

If the strip width value is uncertain, a strip edge position measuring device is placed on the drive side, and the strip edge position zD on the drive side is actually measured, and the average of the _strip edge position _zW on the work side and the strip edge position _zD on the drive side is obtained. A strip width center position current value _zC is calculated as a value. Strictly speaking, the strip width center position current value is preferably the strip width center position directly below the pinch rolls, but if the strip edge position measuring device 5 is sufficiently close to the conveying device, the above calculated value z _C can be used as the strip width center position current value. can be regarded as If more accuracy is desired, a strip edge position measuring device is installed on both the inlet and outlet sides of the conveying device, and the strip width center position is calculated by taking the average of the strip width center position _zC calculated from each actual measurement value. It is preferable to use the current value. In the present disclosure, obtaining the current strip width center position value by calculation from the measured values as described above is expressed as "detecting the current strip width center position value".

Returning to the flowchart of FIG. 6, the description of the method for controlling the conveying apparatus according to the present disclosure is continued. After detecting the width center position current value of the plate 2, it is determined whether or not the pinch rolls 1a and 1b are applying a driving force to the plate 2 in the conveying direction. In one aspect of the control method of the conveying device according to the present disclosure, the electric motor 6 that drives the pinch rolls 1a and 1b performs torque control in order to apply a predetermined tension to the plate material 2. FIG. Specifically, this means controlling the current supplied to the electric motor. Therefore, it is determined whether or not the pinch rolls 1a and 1b are applying a driving force in the conveying direction to the plate material 2 by extracting the control target value of the electric current of the electric motor or measuring the current actual value.

Further, in the flowchart of FIG. 6, when it is determined that the pinch rolls 1a and 1b are applying a driving force in the conveying direction to the plate material 2, the distribution of the load acting between the plate material and the pinch rolls in the plate width direction is Based on the current center position value, the screw-down device on the work side and the drive side of the pinch roll is operated in the direction in which the load on the target width center position value side of the pinch roll between the work side and the drive side becomes relatively large. . This screw down position operation will be described with reference to FIG. In FIG. 7, the strip width center position current value 10 is closer to the working side than the line center 9 which is the center of the trunk length of the pinch roll. To simplify the explanation, it is assumed that the strip width center position target value at this time coincides with the line center 9, but the target value may be other positions. In this case, the control target is to return the plate 2 to the drive side. The screw-down device is operated in a direction in which the load on the target value (line center 9) side, that is, the load on the drive side becomes relatively larger than the load on the work side. Specifically, the pressing position on the working side is operated in the direction of opening the roll gap, and the pressing position on the driving side is operated in the direction of closing the roll gap. In this disclosure, performing the same magnitude of the roll position operation in opposite directions on the working side and the drive side is referred to as a roll roll leveling operation. The load distribution changes without change, and the plate material 2 in FIG. 7 returns to the drive side as the pinch roll rotates.

On the other hand, when it is determined that the pinch rolls 1a and 1b apply a braking force to the plate material 2 in a direction opposite to the conveying direction, the plate width center position Based on the current value, the screw-down devices on the work side and the drive side of the pinch roll are operated so that the load on the target width center position side of the pinch roll between the work side and the drive side becomes relatively smaller. In the example of FIG. 7, with respect to the plate width direction distribution of the load acting between the plate material and the pinch rolls, the load on the side of the plate width center position target value (line center 9), that is, the drive side, is based on the plate width center position current value 10. , the screw-down device is operated in a direction in which the load on the working side becomes relatively small. That is, by performing a roll-down leveling operation in the direction of closing the roll gap on the work side and opening the roll gap on the drive side, the plate material 2 in FIG. 7 returns to the drive side as the pinch roll rotates. When the pinch rolls do not apply driving force or braking force to the plate material, that is, when the pinch rolls are in an idling state, the roll-down leveling operation is not necessarily effective in controlling meandering, and conversely there is a risk of disturbing the shape of the plate material. I have, so I won't do it.

Next, the details of the roll-down leveling operation indicated by S1 and S2 in the flow chart of FIG. 6 will be described by showing a more specific embodiment.

ここで、δは制御パラメータである。式（４）は板幅中心位置現在値ｚ_Ｃと板幅中心位置目標値ｚ_Ｔとの差で板位置誤差を算出し、これに制御パラメータδを掛けたものを板幅中心位置現在値ｚ_Ｃに加算して荷重作用点位置ｚ_{ｐ＿ｒｅｆ}を演算している。なお荷重作用点位置とは作業側荷重測定装置による荷重測定値Ｐ_Ｗと駆動側荷重測定装置による荷重測定値Ｐ_Ｄの二つの力を、荷重およびモーメントバランスのとれる一つの集中荷重Ｐに置き換えた場合の荷重作用点の位置を示すものである。そして荷重Ｐ_Ｗ，Ｐ_Ｄは板材からピンチロールに作用する荷重の反力であるから、当該荷重作用点位置は、板材とピンチロール間に作用する荷重分布を、荷重およびモーメントバランスの観点から集中荷重に置き換えた場合の荷重作用点位置とも一致する。 As shown in FIG. 8, the plate width of the plate material 2 is defined as b, the coordinate z is defined with the line center 9 as the origin and the working side is positive along the pinch roll axis, and the plate width center position current value 10 is defined as z _c , and let z _T be the coordinate of the strip width center position target value. In the example of FIG. 8, it is assumed that z _T =0, that is, the strip width center position target value coincides with the line center 9 for the sake of simplicity of explanation. At this time, the load application point position target value _{zp_ref} is derived, for example, by the following equation (4).

where δ is a control parameter. Equation (4) calculates the strip position error from the difference between the current strip width center position value _zC and the target strip width center position value _zT , and multiplies this by the control parameter δ to obtain the current strip width center position value z _C is added to calculate the load application point position _{zp_ref} . The position of the load application point is the load measurement value _PW by the work-side load measurement device and the load measurement value PD by the drive-side load measurement device, which is replaced by one concentrated load _P that balances load and moment. It shows the position of the load application point in the case. Since the loads P _W and P _D are reaction forces of the loads acting on the pinch rolls from the plate material, the positions of the load application points concentrate the load distribution acting between the plate material and the pinch rolls from the viewpoint of load and moment balance. It also matches the position of the load application point when it is replaced by the load.

First, a specific example of the roll-down leveling operation of S1 in FIG. 6 will be described in detail when the pinch rolls apply a driving force in the conveying direction to the plate material. In this case, the control parameter δ in equation (4) is set to a negative value. For example, if δ=−0.5, then z p — ref = _{0.5z C} is obtained from equation (4) considering z _T =0. In this _way , as shown in FIG. As a result, the plate width direction distribution 20 of the load acting between the plate material and the pinch roll is, as shown in FIG. 8, based on the plate width center position current value The load on the target value side, that is, the load on the drive side becomes relatively larger than that on the working side.

ここで、ζは板幅中心を原点とし作業側を正とする板幅方向座標、ｐ_Ｃは板幅中心位置の線荷重、ｐ_ｄｆは作業側板端の線荷重と駆動側板端の線荷重の差異である。
式（５）の荷重分布による板幅中心まわりのモーメントＭを計算すると次のようになる。

したがって、板材～ピンチロール間の荷重分布を力およびモーメントに関して等価な集中荷重で置き換えたときの力の作用点の板幅中心からの距離ζ_Ｐは次式で計算される。

式（７）より、荷重作用点位置が板幅中心より駆動側にある場合、すなわちζ_Ｐ＜０の場合、ｐ_ｄｆ＜０となり、駆動側の板材～ピンチロール間荷重が作業側の板材～ピンチロール間荷重よりも大きくなることが理解できる。 The relationship between the load application point position and the load distribution between the plate material and the pinch roll is shown quantitatively. The load distribution between the plate material and the pinch roll is approximated by a linear distribution, and the load p per unit width at an arbitrary position is expressed by the following equation. Hereinafter, the load per unit width will be referred to as line load.

Here, ζ is the strip width direction coordinate with the strip width center as the origin and the work side as positive, p _C is the linear load at the strip width center position, and p _df is the linear load at the strip edge on the working side and the strip edge on the drive side. Difference.
Calculation of the moment M about the strip width center based on the load distribution of Equation (5) yields the following.

Therefore, when the load distribution between the plate material and the pinch roll is replaced with a concentrated load equivalent to the force and moment, the distance ζ _P from the plate width center of the force application point is calculated by the following equation.

From equation (7), when the load application point position is on the drive side from the strip width center, that is, when ζ _P < 0, p _df < 0, and the load between the plate on the drive side and the pinch roll is between the plate on the work side and the plate on the work side. It can be understood that it becomes larger than the load between pinch rolls.

Ｐ_{Ｗ＿ｒｅｆ}，Ｐ_{Ｄ＿ｒｅｆ}は、式（８）で計算されるＰ_{ｄｆ＿ｒｅｆ}とトータル荷重の目標値Ｐ_＿ｒｅｆ＝Ｐ_{Ｗ＿ｒｅｆ}＋Ｐ_{Ｄ＿ｒｅｆ}とから以下の式（９）および式（１０）で計算される。

After the load application point position target value _{zp_ref} is obtained as described above, an example of a specific procedure up to the roll-down leveling operation will be continued. First, load target values P _{W — ref} and P D — _ref on the work side and drive side are derived. Specifically, based on the load application point position target value _{zp_ref} given by equation (4), the pinch roll load left-right difference (working side - drive side), that is, the target value of the differential load _{Pdf_ref} is calculated as the pinch roll load. It is calculated by the following formula derived from the roll moment balance.

P _{W_ref} and P _{D_ref} are calculated by the following equations (9) and (10) from P _{df_ref} calculated by equation (8) and the total load target value P _{_ref} =P _{W_ref} + _{PD_ref} .

Next, based on the load target values P _{W_ref} and P _{D_ref} on the work side and the drive side, respectively, and the current load values on the work side and the drive side measured by the load measuring devices 4a and 4b, the work side and the drive side A target value of the pinch roll reduction position control amount is derived for each. Assuming that the rigidity of the pinch roll device considering the plate thickness, plate width, and elastic constant of the plate material 2 is K for one side, and the current values of the loads measured by the load measuring devices 4a and 4b are P _W and P _D , the pinch roll A working-side target value _{Δg W_ref} and a driving-side target value Δg _{D_ref} of the screw position correction amount of the device are given by the following equations (11) and (12).

式（１３）に基づいて導出した作業側ピンチロール圧下位置制御量の目標値Δｇ_Ｗに基づき作業側の圧下装置３ａを制御すると共に、式（１４）に基づいて導出した駆動側ピンチロール圧下位置制御量の目標値Δｇ_Ｄに基づき駆動側の圧下装置３ｂを操作して、作業側および駆動側それぞれのピンチロール圧下位置を制御する。このようにして圧下位置制御を行うことにより、制御の１サイクルが完結し、以後この一連の操作を繰り返すことで圧下レベリング操作による良好な蛇行制御が実現できる。 Here, _{Δg W_ref} and Δg _{D_ref} are defined as positive in the direction in which the gap between the upper and lower pinch rolls is increased. The target values _{Δg W — ref} and _Δg D — ref of the reduction position correction amounts are multiplied by a scale factor α to calculate the pinch roll reduction position control amounts Δg _W and Δg _D using the following equations (13) and (14).

Based on the target value Δg _W of the working side pinch roll screw down position control amount derived based on the equation (13), the working side screw down device 3a is controlled, and the drive side pinch roll screw down position derived based on the equation (14). The driving-side screw-down device 3b is operated based on the target value _ΔgD of the control amount to control the pinch roll screw-down positions on the working side and the driving side. By performing the screw down position control in this manner, one cycle of control is completed, and by repeating this series of operations thereafter, it is possible to realize excellent meandering control by the screw down leveling operation.

In the above specific example, the roll position control may include a simultaneous roll down component in the same direction on the work side and the drive side, but this component controls the pinch roll load, which is the sum of the work side load and the drive side load. will do. On the other hand, what is essential to the control method of the present disclosure is the roll-down leveling component in opposite directions on the work side and the drive side, and this component controls the differential load, which is the difference between the work side load and the drive side load. Therefore, it is also effective to entrust the load control by the simultaneous reduction component to other control functions and to specialize the reduction leveling operation for the meandering control of the plate. Specifically, the differential load control amount ΔP _df is calculated from the difference between the differential load target value P _{df_ref} and the differential load current value P _df calculated by the equation (8), and the reduction leveling control amount target for achieving this is calculated. A value _{Δg df_ref} is obtained in consideration of the plate thickness, width, elastic constant, and deformation characteristics of the pinch roll device, and the roll-down leveling control amount Δg _df is obtained in consideration of the scale factor.

Next, with reference to FIG. 9, the procedure of S1 in FIG. 1 when the strip width center position current value 10 is on the driving side of the line center 9 will be described. Also in this case, the position of the load application point is calculated by the formula (4). Considering δ=−0.5 and z _T =0, the position of the load application point is z _{p_ref} =0.5z _C as in FIG. However, in the case of FIG. 9, since z _C <0, the position of the load application point is located on the working side of the current strip width center position value 10 . Therefore, in the case of FIG. 9, contrary to FIG. 8, the load between the plate material and the pinch rolls on the working side is made larger than the load between the plate material and the pinch rolls on the driving side.

Next, a specific example of the roll-down leveling operation in S2 of FIG. 6 will be described with reference to FIG. The procedure of S2 is executed when it is determined that the pinch rolls apply a braking force to the plate in the conveying direction. The procedure in this case is also the same as the procedure of S1 described above, except for one point. The only difference is that the control parameter δ in equation (4) is set to a positive value. For example, if δ=0.5 and _{zT=0 in Equation (4), zp_ref = 1.5zC} is obtained. As a result, as shown in FIG. 10, when z _C >0, that is, when the strip width center position current value 10 is on the working side of the line center 9, the load application point position target value is further than the strip width center position current value 10. As shown in FIG. 10, the plate width direction distribution 20 of the load acting between the plate material and the pinch roll is located on the work side, and the plate width center position target value side is based on the plate width center position current value as shown in FIG. , that is, the load between the drive-side plate material and the pinch rolls is relatively smaller than the load between the work-side plate material and the pinch rolls. The procedure after the load application point position target value is obtained as described above is exactly the same as the procedure of S1.

Next, with reference to FIG. 11, the procedure of S2 in FIG. 6 when the strip width center position current value 10 is on the driving side of the line center 9 will be described. Also in this case, the position of the load application point is calculated by the formula (4). If δ=0.5 and _{zT=0 as in the example of FIG. 10, zp_ref = 1.5zC} is obtained. However, in the case of FIG. 11, since z _C <0, the position of the load application point is located on the drive side of the current strip width center position value 10 . Therefore, in the case of FIG. 11, contrary to FIG. 10, the load between the work-side plate material and the pinch rolls is made smaller than the load between the drive-side plate material and the pinch rolls.

式（１５）をｚ_Ｃについて解くと板幅中心位置現在値ｚ_Ｃが次式で得られる。

式（１６）によれば作業側および駆動側の荷重測定値より板材の板幅中心位置を求めることができる。ただし、式（１６）は板材～ピンチロール間荷重分布が板幅方向に左右対称となっていることを前提とした計算式であり、左右非対称となっている場合は、その非対称性が荷重測定値の左右差Ｐ_Ｗ－Ｐ_Ｄにおよぼす影響を除外した上で板幅中心位置ｚ_Ｃを計算しなければならない。例えば、板材～ピンチロール間荷重分布が直線分布であり、作業側の線荷重と駆動側の線荷重との差異すなわち荷重分布左右差がｐ_ｄｆとなっている場合、この荷重分布左右差がＰ_Ｗ－Ｐ_Ｄにおよぼす影響は、板幅をｂとするとき、ｐ_ｄｆ・ｂ^２／（６ａ）で与えられるから式（１６）の代わりに次式を用いて板幅中心位置 を計算する。

In one aspect of the control method of the conveying device of the present disclosure, the work measured by the load measuring devices arranged at both ends in the axial direction of the pinch roll without the plate end position measuring device 5 shown in FIG. The current width center position of the strip is detected from the measured values of the side and drive side loads, and the roll-down leveling operation is performed based on this current width center position. Hereinafter, an example of a method for calculating the strip width center position current value from the load measurement value will be specifically described with reference to FIG. 12 . In FIG. 12, the load P acting on the pinch roll from the plate material is represented by a concentrated load acting on the width center of the plate material. The plate width center of the plate material is located at the position _zC from the line center 9, the load measurement value measured by the load measuring device on the working side of the pinch roll axial direction both ends is _PW , and the load measuring device on the driving side is PW. Let _PD be the measured load measurement. When the distance between the work-side load measuring device and the drive-side load measuring device is a, the following relational expression holds between these loads from the balance condition of the moment of the pinch roll.

Solving equation (15) for z _C yields the strip width center position current value z _C by the following equation.

According to the formula (16), the width center position of the plate can be obtained from the load measurement values on the working side and the driving side. However, formula (16) is a calculation formula assuming that the load distribution between the strip material and the pinch rolls is symmetrical in the strip width direction. The strip width center position z _C must be calculated after excluding the influence on the left-right difference P _W −P _D of the value. For example, if the load distribution between the plate material and pinch rolls is a linear distribution, and the difference between the linear load on the work side and the linear load on the drive side, that is, the lateral difference of the load distribution is p _df , the lateral difference of the load distribution is P The influence on _W -P _D is given by p _df ·b ² /(6a) where b is the strip width, so the following equation is used instead of equation (16) to calculate the strip width center position.

ここで、ｍは板材を単位厚さだけピンチロール圧下したときの線荷重増分を表す板材の弾性定数であり、Ｄは、第二種平行剛性と呼ばれ、荷重分布左右差が単位量だけ変化したときにピンチロールを含めた搬送装置の弾性変形により生ずる板厚左右差を表わすパラメータであり、何れも設備仕様および板材の寸法と弾性係数が与えられれば公知の方法により予め計算できるものである。 Here, the load distribution left-right difference p _df is assumed to be zero at the initial roll-down position, and the subsequent roll-down leveling operation Δg _df is calculated in consideration of the elastic deformation of the pinch roll and the plate material. The amount of change Δp _df in the lateral difference in the load distribution between the plate material and the pinch roll can be obtained by calculating, for example, using the following equation and integrating it in time series.

Here, m is the elastic constant of the plate material that represents the linear load increment when the plate material is pressed down by a unit thickness with pinch rolls, and D is called the second type parallel stiffness, and the load distribution lateral difference changes by the unit amount. It is a parameter that expresses the lateral difference in plate thickness caused by elastic deformation of the conveying device including pinch rolls when it is pressed. .

In FIG. 13, in a thin strip hot rolling facility in which n pinch roll devices are arranged on a runout table from a finishing mill 12 to a pre-winding pinch roll 13 and a winder 14 to constitute a conveying device, 4 shows an embodiment of the control method of the present disclosure in which the strip is threaded while tension is applied to the tip of the strip. As for the pinch roll devices, a #1 pinch roll device is arranged on the most upstream side immediately after the finishing mill 12 and a #n pinch roll device is arranged on the most downstream side immediately before the pre-winding pinch roll 13 . In FIG. 13(a), the finishing rolling mill 12 performs rolling by driving the work rolls under speed control as the speed pivot of the rolling line, and the leading end of the strip material is gripped by the #1 pinch roll device, and the #1 By setting the electric motor torque of the pinch roll device to α·T, tension α·σ is applied to the plate material between the finishing mill 12 and the #1 pinch roll device.

In FIG. 13(b), the plate material advances from FIG. A tension σ is applied between the pinch roll device and the #2 pinch roll device. Further, the electric motor torque T of the #2 pinch roll device is added, and at the same time, the electric motor torque of the #1 pinch roll device is changed from α·T to -(1-α)T. By doing so, the tension α·σ of the plate material between the finishing mill 12 and the #1 pinch roll device can be maintained at the same value.

In FIG. 13(c), the plate material advances further than in FIG. 13(b), the leading edge of the plate material is gripped by the #3 pinch roll device, and the motor torque of the #3 pinch roll device is set to αT. A tension α·σ is applied between the #2 pinch roll device to the #3 pinch roll device. Further, the electric motor torque α·T of the #3 pinch roll device is added, and at the same time, the electric motor torque of the #2 pinch roll device is changed from T to (1−α)T. By doing so, it is possible to maintain the plate material tension σ between the #1 pinch roll device and the #2 pinch roll device, and the plate material tension α σ between the finishing rolling mill 12 and the #1 pinch roll device. .

In FIG. 13(d), the plate material advances further than in FIG. 13(c), and the tip of the plate material is gripped by the #4 pinch roll device. A tension σ is applied between the #3 pinch roll device to the #4 pinch roll device. Further, the electric motor torque T of the #4 pinch roll device is added, and at the same time, the electric motor torque of the #3 pinch roll device is changed from α·T to -(1-α)T. By doing so, the tension α/σ of the plate material between the #2 pinch roll device and the #3 pinch roll device, the tension σ of the plate material between the #1 pinch roll device and the #2 pinch roll device, and the finishing rolling mill 12 The tension α·σ of the plate material between the pinch roll devices of ˜#1 can be maintained.

In FIG. 13(e), the plate material advances further than in FIG. 13(d), the leading edge of the plate material is gripped by the #5 pinch roll device, and the motor torque of the #5 pinch roll device is set to αT. A tension α·σ is applied between the #4 pinch roll device to the #5 pinch roll device. Further, the electric motor torque α·T of the #5 pinch roll device is added, and at the same time, the electric motor torque of the #4 pinch roll device is changed from T to (1−α)T. By doing so, the tension of the plate on the upstream side of the #4 pinch roll device can be maintained in the state shown in FIG. 13(d).

In FIG. 13(f), the plate material advances further than in FIG. 13(e), and the tip of the plate material is gripped by the #6 pinch roll device. A tension σ is applied between the #5 pinch roll device to the #6 pinch roll device. Furthermore, the electric motor torque T of the #6 pinch roll device is added, and at the same time, the electric motor torque of the #5 pinch roll device is changed from α·T to −(1−α)T. By doing so, the tension of the plate on the upstream side of the #5 pinch roll device can be maintained in the state shown in FIG. 13(e).

In FIG. 13, the values of the electric motor torque or the tension of the plate material enclosed in squares, for example, in FIG. From FIGS. 13(a) to 13(f), in this embodiment, the electric motor torque of the most downstream pinch roll device that grips the tip of the plate material and one pinch roll device on the upstream side adjacent thereto It can be seen that the tension acting on the plate material can be maintained by simply changing , without changing the electric motor torque of the pinch roll device on the upstream side. This is possible because the driving force acting on the plate from the most downstream pinch roll device that grips the tip of the plate, for example, the electric motor torque T of the #2 pinch roll device in FIG. A value significantly different from the driving force applied when the leading edge of the plate material is bitten into the adjacent upstream pinch roll device, for example, the electric motor torque α T of the #1 pinch roll device in FIG. 13(a) This is due to That is, if the electric motor torques of the most downstream pinch roll device that grips the tip of the plate material and the pinch roll devices on the upstream side are listed in order, the state in which the tip of the plate material is gripped by the #5 pinch roll device, that is, FIG. ), #5: α T, #4: (1-α) T, #3: -(1-α) T, #2: (1-α) T, #1: -(1- α) T, but in the state where the leading edge of the plate material is gripped by the #6 pinch roll device, that is, in the state of FIG. #4: (1-α)T, #3: -(1-α)T, #2: (1-α)T, #1: -(1-α)T, #4 pinch It can be confirmed that there is no need to change the electric motor torque of the pinch roll device on the upstream side of the roll device, and that the tension acting on the plate material does not change.

In FIG. 26, similar to FIG. 13, in a thin-strip hot rolling facility in which n pinch roll devices are arranged on a runout table to constitute a conveying device, a strip is threaded while applying tension to the leading end of the strip. An example of a control method is shown. In the example of FIG. 26, the motor torque of the pinch roll device on the most downstream side that grips the leading edge of the plate material is always α·T. For this reason, assuming that the tension acting on the plate material has two levels of σ and α·σ as in the case of FIG. 13, the motor torque of the pinch roll device is That is, in the state of FIG. 26(e), #5: α·T, #4: (1−α)T, #3: −(1−α)T, #2: (1−α)T, #1 :-(1-α)T, but in the state where the leading edge of the plate material is gripped by the #6 pinch roll device, that is, in the state of FIG. 1-α)T, #4: -(1-α)T, #3: (1-α)T, #2: -(1-α)T, #1: (1-α)T, and so on. 26(e) to FIG. 26(f). Such an operation is accompanied by frequent reversal of the torque of the electric motor, which hinders stable strip threading and accelerates deterioration of the equipment of the pinch roll device, which is not preferable. Furthermore, in the example of FIG. 26, in the state of FIG. In the state shown in FIG. 26(f), the tension σ always acts on the portion of the plate existing between the #4 pinch roll device and the #5 pinch roll device. Since the tension level acting on the strip in the longitudinal direction is always different in this way, especially in the case of hot rolling, the risk of causing the strip width to fluctuate in the longitudinal direction increases, so the example of FIG. .

FIG. 14 shows subsequent procedures of the control method of the conveying device in which n pinch roll devices are arranged on the runout table of the strip hot rolling facility shown in FIG. In FIG. 14(a), the leading edge of the plate reaches the front of the #n-1 pinch roll device, and in FIG. 14(b), the leading edge of the plate is gripped by the #n-1 pinch roll device and #n -1 T is the electric motor torque of the pinch roll device. As a result, the tension on the entry side of the #n-1 pinch roll device is σ.

In FIG. 14(c), the leading edge of the plate material is gripped by the #n pinch roll device, and by setting the motor torque of the #n pinch roll device to α T, the #n−1 pinch roll device and the #n pinch roll The tension between the devices becomes α σ, and at the same time, by changing the motor torque of the #n-1 pinch roll device from T to (1-α)T, the tension on the upstream side of the #n-1 pinch roll device is reduced. can be maintained.

In FIG. 14(d), the leading edge of the plate passes through the pre-winding pinch roll 13 and is wound on the winder 14, and the electric motor torque of the pre-winding pinch roll 13 and the winder 14 causes the #n pinch roll to the pre-winding. A tension σ acts between the pinch rolls 13, and at the same time, by changing the motor torque of the #n pinch roll device to −(1−α)T, the tension acting on the plate material on the upstream side of the #n pinch roll device can be maintained.

FIG. 15 shows the subsequent procedure of the control method of the conveying device in which n pinch roll devices are arranged on the runout table of the strip hot rolling facility shown in FIG. It shows the control method. First, before the trailing end of the strip material passes through the finishing rolling mill 12, the speed pivot of the rolling line is shifted from the finishing rolling mill 12 to the winding machine 14, and the winding machine 14 is changed from the previous torque control to the speed control of the sheet material. switch to Then, as shown in FIG. 15(a), when the trailing end of the plate material passes through the finishing mill 12, the tension between the finishing mill 12 and the #1 pinch roll device becomes 0. In order to maintain the tension σ between the #2 pinch roll device, the motor torque of the #1 pinch roll device is changed from α·T to −T. By this operation, the tension of the plate on the downstream side of the #1 pinch roll device can be maintained in the state shown in FIG.

In FIG. 15(b), when the trailing end of the plate passes through the #1 pinch roll device and the plate tension between the #1 pinch roll device and the #2 pinch roll device becomes 0, the electric motor of the #2 pinch roll device Change the torque from (1-α)T to -αT. By this operation, the tension of the plate on the downstream side of the #2 pinch roll device can be maintained in the state shown in FIG.

In FIGS. 15(c) to (f), each time the trailing end of the plate passes through the #2, #3, #4, and #5 pinch roll devices in sequence, the most upstream pinch that grips the plate at each time point. By changing the electric motor torque of the roll device to -T or -α·T, the tension applied to the plate material on the downstream side of the pinch roll device is prevented from changing with time.

13 to 15 show an embodiment with two levels of tension acting on the plate material between the pinch roll devices, but FIGS. 16 to 18 show an embodiment with three levels of tension acting on the plate material between the pinch roll devices. is shown. In this embodiment, as shown in FIGS. 16 and 17, when the leading edge of the plate material is sequentially gripped from the #1 pinch roll device to the #n pinch roll device, the leading edge of the plate material is gripped at each time point. The electric motor torque of the most downstream pinch roll device is periodically changed to α T, 2 α T, 3 α T, 2 α T, α T, 2 α T, . The electric motor torque of the upstream pinch roll device adjacent to the side pinch roll is changed so that the plate tension on the upstream side of the pinch roll device does not change. By doing so, finally, the motor torque of each pinch roll device is -αT, -αT, αT, αT, -αT from the upstream side to the downstream side. , -α・T, . do. FIG. 18 shows the control method when the trailing edge of the plate material is threaded. Similar to the case of FIG. By changing the electric motor torque of the most upstream pinch roll device to -α T, -2 α T, or -3 α T, the tension acting on the plate material downstream from the pinch roll device I try not to change it over time. By carrying out such control, the electric motor of each pinch roll device always exerts a significant driving force or braking force, and effective meandering control is carried out for the conveying device as a whole to achieve stable strip threading. can be realized.

13-15, as well as the embodiment of FIGS. 16-18, have all assumed a constant value of α from the upstream pinch roll device to the downstream pinch roll device, whereas the embodiment of FIG. 3, it is possible to change the tension level acting on the plate according to the situation by changing the value of α from the upstream side to the downstream side.

19 to 21 show, as an application example of the embodiment shown in FIGS. 1 shows an embodiment for realizing FIG. 19 shows a control method when threading the leading edge of the plate material. FIGS. 19(a) to (c), in which the leading edge of the plate material is gripped by the pinch roll devices #1 to #3, are completely the same control modes as FIGS. 16(a) to (c), but FIG. ), the leading edge of the plate material is gripped by the #4 pinch roll device and the motor torque of the #4 pinch roll device is set to 3αT. Make contactless. Also, the electric motor of the #3 pinch roll device is switched from the drive torque control of 3α·T to the speed control based on the synchronous speed with the plate material. Thereafter, in FIGS. 19(e) and (f), the leading edge of the plate material reaches the #5 pinch roll device and the #6 pinch roll device, respectively, and the motor torque of 3α·T is sequentially applied to the #4 pinch roll device and the #5 pinch roll device. The screw down device of the pinch roll device is operated to release the upper pinch roll.

FIG. 20 shows an embodiment in which the plate material advances further from the state of FIG. In FIG. 20(a), the leading edge of the plate material is gripped by the #n-1 pinch roll device and a drive torque of 3αT is applied, and at the same time, although not shown, the roll-down device of the #n-2 pinch roll device is operated. to open the upper pinch roll. In FIG. 20(b), the leading edge of the plate material is gripped by the #n pinch roll device and a drive torque of 3αT is applied, and at the same time, the roll-down device of the #n-1 pinch roll device is operated to release the upper pinch roll. there is Then, in FIG. 20(c), the leading edge of the plate material is wound around the winder 14, a tension of 3α·σ is applied to the plate material by the winder 14 and the pre-winding pinch roll 13, and the roll-down device of the #n pinch roll device is applied. is operated to open the upper pinch roll. In the state shown in FIG. 20(c), that is, in the region of the pinch roll device in the non-contact state, the rolling of the stationary portion of the plate progresses with a tension of 3α·σ applied to the plate.

FIG. 21 shows a control method when the steady rolling state of FIG. First, before the trailing end of the strip material passes through the finishing rolling mill 12, the speed pivot of the rolling line is shifted from the finishing rolling mill 12 to the winding machine 14, and the winding machine 14 is changed from the previous torque control to the speed control of the sheet material. switch to Then, as shown in FIG. 21(a), when the trailing end of the strip passes through the finishing mill 12, the screw down device of the #3 pinch roll device, which had been in the open state of the upper pinch roll until then, is operated to roll the strip. After contact is made and a predetermined rolling force is applied, the motor is switched to torque control and a braking torque of -α·T is applied. After that, as shown in FIGS. 21(b), (c), and (d), the trailing ends of the plate material pass through the #1, #2, and #3 pinch roll devices in sequence, and the upper pinch rolls are opened until then. After operating the roll-down devices of the existing #4, #5, and #6 pinch roll devices to bring them into contact with the plate and apply a predetermined roll-down force, the electric motors are switched to torque control to give a braking torque of -αT. By doing so, it becomes possible to wind up the plate material without substantially changing the tension in the vicinity of the tail end of the plate material. Then, in FIG. 21(e), when the trailing end of the plate passes through the #n-2 pinch roll device (not shown), the motor torque of the #n-1 pinch roll device is changed to -αT and the #n pinch roll device is -2α·T, and the tension 3α·σ between the #n pinch roll device and the pre-winding pinch roll 13 is maintained. Although not shown, as a preliminary stage of FIG. 21(e), when the trailing end of the plate material passes through the #n-3 pinch roll device, the #n-2 pinch roll device and the #n-1 pinch roll device , #n, the pinch roll device grips the vicinity of the tail end of the plate material and applies a motor torque of -α·T. Then, as shown in FIG. 21(f), when the trailing end of the plate material passes through the #n-1 pinch roll device, the motor torque of the #n pinch roll device is set to -3αT, and the #n pinch roll device ~ A tension of 3α·σ between the pre-winding pinch rolls 13 is maintained.

In the embodiments of FIGS. 19 to 21, at least one pinch roll device always grips the leading edge of the plate material when the plate material is threaded, and two or three pinch roll devices are always on the most upstream side of the plate material. However, it goes without saying that the cardinal number of the pinch rolls that always grip these plate materials can be changed as required.

[Action and effect of the present embodiment]
Conventionally, in the production and processing line of plate materials, in order to smoothly convey the plate material while applying tension to the plate material and preventing out-of-plane deformation, a device that pinches and conveys the plate material with a pair of upper and lower pinch rolls is used. In such an apparatus, the center of the width of the plate may deviate from the center of the plate manufacturing/processing line, and in the worst case, a part of the plate may stick out from the pinch roll body and the plate may be damaged. . In order to avoid this phenomenon, for example, in Patent Document 1, in addition to controlling the pinch roll profile and bending force, the loads on the working side and the driving side are measured, and the rolling position on the side with the larger load is relatively determined. An apparatus is disclosed for implementing roll-down leveling control in the tightening direction. The concept of this reduction leveling control is the same as that of meandering control of a rolling mill. Since the load on the side where the plate meanders increases, this is detected and the reduction position on the side where the load increases is relatively tightened. It implements the roll-down leveling control in the direction. Here, as a specific example, consider a case where the plate is shifted toward the working side. In the case of rolling, the roll reduction and elongation on the work side increase due to the roll-down leveling operation that tightens the work side. will lean to the side. By rolling the inclined plate in this manner, the plate returns to the drive side. In the case of a conveying device using pinch rolls, the sheet material does not undergo plastic deformation unlike rolling, but since the sheet material elastically stretches in the conveying direction due to the compression of the pinch rolls, the same meandering control effect as rolling is qualitatively expected. It was thought possible.

Based on the concept described above, the inventors conducted an experiment using a conveying device and a reduction leveling control method similar to those disclosed in Patent Document 1. FIG. As a result, although there were conditions under which meandering was well controlled, there were also cases in which meandering became severe due to roll-down leveling control. Therefore, as a result of investigating the relationship between the meandering characteristics of the pinch roll device and the experimental conditions in detail, the following facts were clarified.

(A) When the tension applied to the plate material on the entry side of the pinch roll device and the tension applied to the plate material on the exit side are equal, the reduction leveling operation in the direction of tightening the reduction position on the side where the plate meanders Although the meandering of the plate material was somewhat suppressed, its sensitivity was low, and when the disturbance was large, the roll-down leveling operation for suppressing the meandering became excessive, and the plate material deformed plastically, resulting in deterioration of the plate shape.

(B) When the tension on the entry side of the pinch roll device is greater than the tension on the exit side, the meandering of the plate material tends to diverge due to the roll-down leveling operation in the direction of tightening the roll-down position on the side where the plate meanders, and the plate position is stabilized. I couldn't do it. Conversely, by performing a roll-down leveling operation in the direction of opening the roll-down position on the side where the plate meandered, the meandering of the plate was suppressed, and stable threading was achieved.

(C) When the tension on the exit side of the pinch roll device is greater than the tension on the entry side, the meandering of the plate material is suppressed by the roll-down leveling operation in the direction of tightening the roll-down position on the side where the plate meanders, and stable threading can be achieved. rice field.

As described above, when the entry-side tension is greater than the exit-side tension, not only does the prior art roll-down leveling control, that is, the roll-down leveling control for relatively tightening the roll-down position on the side where the plate meanders, not only does it not function, but conversely, the roll-down leveling control does not function. It became clear that it promotes meandering. In this case, it has been clarified that roll-down leveling control in which the roll-down position is relatively opened in the direction opposite to that of the conventional technique, ie, the roll-down position on the side where the plate meanders, is effective.

In order to examine whether this experimental result is universal, the mechanism of the above phenomenon was considered.

Conventionally, the elastic elongation of the plate material has been considered as the basic mechanism of meandering control by the leveling operation of pinch rolls. However, this mechanism alone cannot explain the reversal phenomenon of meandering characteristics caused by the change in tension balance on the entry and exit sides. Therefore, the inventors of the present invention have made intensive studies on the mechanism of this phenomenon, and have come up with a new meandering mechanism of the pinch roll device through the following thought process.

In the conventional meandering mechanism due to the elastic elongation of the plate material, only the pinch force acting on the plate material from the pinch rolls, that is, the rolling force in the plate thickness direction, was considered. cannot explain the phenomenon. Therefore, we considered the effect of the tension balance on the entry and exit sides on the force acting on the plate from the pinch rolls. FIG. 22 schematically shows the force in the conveying direction applied to the plate in the vicinity of the pinch rolls. FIG. 22 shows a case where the tension on the entry side is greater than the tension on the exit side. In this case, the plate material is conveyed from the pinch rolls to the plate material as indicated by arrows 23a and 23b depending on the balance condition of the conveying direction force acting on the plate material. A directional driving force must be acting. In other words, since the driving forces 23a and 23b are acting on the plate material from the pinch rolls, the tension on the entry side becomes greater than the tension on the exit side.

FIG. 23 shows a top plan view of FIG. 22. In this example, it is assumed that the load distribution 20 between the plate material and pinch rolls is greater on the working side. In this case, since the pinch rolls press the working side of the plate more strongly than the driving side, the driving force acting on the plate from the pinch rolls is such that the working side driving force 23a-1 is greater than the driving side driving force 23b-2. Conceivable. As a result, a moment 25 acts on the plate material from the pinch rolls, and the advancing speed of the plate material becomes slightly faster on the working side than on the driving side, and the plate material is tilted as shown in FIG. In this way, the plate material inclined toward the work side upstream of the entry side is sent in the conveying direction by the pinch rolls, so that the plate meanders toward the work side. In other words, it is possible to explain that the screw-down leveling operation increases the screw-down and meanders to the side where the load increases. From these considerations, it can be confirmed that the above experimental fact (B) is a universal phenomenon. The driving force acting on the plate material from the pinch rolls is actually a force distributed over the contact area between the plate material and the pinch rolls. Let me show you.

Contrary to FIG. 22, FIG. 24 shows the force applied to the plate material in the conveying direction when the tension on the delivery side is greater than the tension on the entry side. In this case, depending on the balance condition of the force acting on the plate in the conveying direction, the pinch rolls must exert braking forces on the plate in the direction opposite to the conveying direction as indicated by arrows 24a and 24b. In other words, since the braking forces 24a and 24b are applied from the pinch rolls to the plate material, the exit side tension becomes larger than the entry side tension.

FIG. 25 shows a top plan view of FIG. 24. In this example, it is assumed that the load distribution 20 between the plate material and the pinch rolls is large on the working side. In this case, since the pinch rolls press the working side of the plate more strongly than the driving side, the braking force acting on the plate from the pinch rolls is that the working side braking force 24a-1 is greater than the driving side braking force 24b-2. Conceivable. As a result, a moment 25 acts on the plate material from the pinch rolls, and the advancing speed of the plate material is slightly slower on the working side than on the driving side, and the plate material is tilted as shown in FIG. In this way, the plate material inclined toward the driving side upstream of the entry side is sent in the conveying direction by the pinch rolls, so that the plate meanders toward the driving side. In other words, by the roll-down leveling operation, roll-down is strengthened and the roll meanders to the side opposite to the side where the load is increased. This meandering characteristic is qualitatively the same as the mechanism considering the elastic elongation of the plate material. From these considerations, it can be confirmed that the above experimental fact (C) is a universal phenomenon.

By the way, when the tension on the entry side is significantly larger than the tension on the exit side, that is, when the pinch rolls apply a driving force in the conveying direction to the plate material, without exception, the plate meanders to the side where the reduction is increased and the load is increased. . Considering that this meandering characteristic is in the opposite direction to the mechanism that considers the elastic elongation of the plate material, the effect of the elastic elongation of the plate material on the meandering characteristic is due to the difference in tension between the entrance and exit sides, that is, the driving force or braking force of the pinch roll. It is concluded that the effect is extremely small compared to the effect of From these considerations, it can be confirmed that the above experimental fact (A) is a universal phenomenon. Therefore, it can be confirmed that the pinch roll device needs to apply a significant driving force or braking force to the plate material in order to effectively control meandering by the roll-down leveling operation of the pinch roll device.

The present invention has been made through the above discoveries and considerations. In a conveying apparatus having a plurality of pinch roll devices in series for compressing and conveying a sheet material with pinch rolls, the tension of the sheet material is controlled within a predetermined allowable range. It also discloses a control method for performing good meandering control. In particular, in order to control the tension of the plate material within a predetermined allowable range, at least one pinch roll device applies a driving force to the plate material in the conveying direction, and at least another pinch roll device applies a driving force to the plate material in the direction opposite to the conveying direction. In a pinch roll device that applies a braking force to control the meandering of the plate and applies a driving force in the conveying direction to the plate, the distribution of the load acting between the plate and the pinch rolls in the plate width direction , operating the screw-down devices on the working side and the driving side of the pinch roll device in a direction to make the load on the side of the target width center position relatively larger than the other, based on the current value of the width center position. In a pinch roll device that applies a braking force in the direction opposite to the conveying direction, the distribution of the load acting between the plate and the pinch roll in the plate width direction is based on the plate width center position target value based on the plate width center position current value. The screw-down devices on the working side and the drive side of the pinch roll device are operated in the direction to make the load on the value side relatively smaller than on the other side.

By carrying out such control, it is possible to realize tension control and meandering control of the plate material corresponding to all conditions in a conveying device having a plurality of pinch roll devices in series.

1a, 1b... pinch roll 2... plate material 3a, 3b... screw down device 4a, 4b... load measuring device 5... plate edge position measuring device 6... electric motor 7a, 7b... spindle 8... pinion stand , 9... Line center, 10... Present value of plate width center position, 11... Conveying direction of plate material, 12... Finishing rolling mill, 13... Pinch roll before winding, 14... Winding machine, 20... Load between plate material and pinch roll Distribution 21: entry side tension 22: exit side tension 23a, 23b, 23a-1, 23a-2: driving force acting from pinch rolls to plate material 24a, 24b, 24a-1, 24a-2: pinch rolls 25: Moment acting on the plate material from pinch rolls 100: Plate material conveying device.

Claims (6)

A pair of upper and lower pinch rolls, a driving device for driving the pinch rolls, a screw down device at each of the axial ends of at least one of the upper and lower pinch rolls, and each of the axial ends of at least one of the upper and lower pinch rolls. A control method for a plate material conveying device having a plurality of pinch roll devices equipped with a load measuring device in series on the same line,
At least one of the pinch roll devices imparts a driving force to the plate material in the conveying direction, and at least another one of the pinch roll devices imparts a braking force to the plate material in a direction opposite to the conveying direction ,
Aiming to detect the width center position current value of the plate material pinched by the pinch rolls, and bring the width center position current value closer to the width center position target value,
In the at least one unit in which the pinch rolls apply a driving force in the conveying direction to the plate material, the present value of the plate width center position is calculated with respect to the plate width direction distribution of the load acting between the plate material and the pinch rolls. As a reference, the screw-down devices on the working side and the driving side of the pinch roll device are operated in a direction in which the load on the side of the target width center position is relatively larger than the other,
In the at least one other unit in which the pinch roll applies a braking force in a direction opposite to the conveying direction to the plate material, the distribution of the load acting between the plate material and the pinch roll in the plate width direction is The screw-down devices on the working side and the driving side of the pinch roll device are operated in a direction to make the load on the side of the target width center position relatively smaller than the other, with reference to the current center position value. A control method for a conveying device. When the tip of the plate material is threaded, every time the tip of the plate material bites into the pinch roll device arranged downstream, the most downstream pinch roll device that grips the tip of the plate material acts on the plate material. 2. The method of controlling a conveying apparatus according to claim 1 , wherein the force is set to a value significantly different from the driving force applied when the leading edge of the plate material is bitten into an adjacent pinch roll device on the upstream side. To prevent the tension acting on the plate material existing between pinch roll devices on the upstream side of the pinch roll device on the most downstream side gripping the leading end portion of the plate material from changing with time when the leading end portion of the plate material is threaded. 3. The method of controlling a conveying device according to claim 2 , wherein the motor torque of the driving device of said upstream pinch roll device is controlled. When the tail end of the plate material is passed, every time the tail end of the plate material passes through the pinch roll device arranged on the upstream side, the most upstream pinch roll device grips the tail end of the plate material at that time. The electric motor torque of the driving device of the most upstream pinch roll device is controlled so as not to change the tension acting on the plate material existing between the adjacent downstream pinch roll devices over time. A control method for the described transport device. When the leading end of the plate material is threaded, every time the leading end of the plate material bites into the pinch roll device arranged downstream, the leading end of the plate material is positioned upstream from the most downstream pinch roll device that grips the leading end of the plate material. The pressing device of the pinch roll device gripping the plate material is operated to release the pressing force, and at the same time, the most downstream pinch is operated so as to maintain the tension acting on the plate material at the position where the pressing force is released. 2. The method of controlling a conveying device according to claim 1 , wherein the motor torque of a driving device of the roll device is controlled. When the tail end of the plate material is threaded, the tail end of the plate material is gripped every time the tail end of the plate material passes through the pinch roll device arranged on the upstream side and the rolling force is released. Of the pinch roll devices that are arranged downstream from the most upstream pinch roll and stand by in the state of releasing the rolling force, the pinch roll device on the most upstream side grips the plate material and applies a predetermined rolling force. and simultaneously controlling the electric motor torque of the driving device of the pinch roll device so as to maintain the tension of the plate material downstream from the pinch roll device. .

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