JPH07102381B2 - Method for adjusting plate shape of rolled material by rolling mill - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention applies a plate shape in the plate width direction of a rolled material rolled by a rolling mill composed of a plurality of rolls combined in multiple stages to the rolls. The present invention relates to a plate shape adjusting method for a rolled material, which is adjusted by controlling an actuator.

[Prior art]

As a method for adjusting the plate shape of the rolled material by the rolling mill as described above, for example, the method disclosed in JP-A-63-177910 can be mentioned.

This method for adjusting the plate shape of a rolled material is such that a plate shape in the plate width direction of the currently detected rolled material, for example, represented by an elongation distribution of I-units, is brought closer to a target plate shape. The work roll bender force and the intermediate roll bender force are adjusted by controlling each actuator acting on the roll or the intermediate roll. A plurality of actuators may be provided for each roll bender force.

According to the plate shape adjusting method, the degree of change of the plate shape with respect to the control amount of the actuator is expressed, and based on the influence coefficient preset for each of these actuators,
A control function for calculating the control amount of each actuator is calculated, and this control function controls each of the actuators at a predetermined control cycle, that is, at a so-called data sampling cycle.

In particular, in the plate shape adjusting method, when the actuator for adjusting one of the roll bender forces reaches its drive limit, this actuator is kept in the drive limit state, and the currently detected plate shape is targeted. In order to approximate the plate shape of the other roll bender, the gain of the control system of the other roll bender force is corrected and the actuator for adjusting the other roll bender force is controlled. As a result, after the actuator for adjusting the one roll bender force reaches the drive limit, the actuator for adjusting the other roll bender force should use the correction gain as it is when the two roll bender forces are acting. Therefore, the plate shape of the rolled material is properly adjusted.

[Problems to be Solved by the Invention]

According to the above-mentioned conventional plate shape adjusting method, when the actuator for adjusting one roll bender force reaches its drive limit, the gain of the control system for the actuator for adjusting the other roll bender force is adjusted. However, there is a case where each of the actuators that adjust the roll bender force reaches their respective drive limits at the same time, or a plurality of actuators that adjust the same roll bender force reach their respective drive limits at the same time.

However, in the above-mentioned conventional plate shape adjusting method, when two or more actuators as described above simultaneously reach their respective driving limits, an index is given as to which actuator gain is to be preferentially corrected. Absent.

On the other hand, when two or more actuators reach their respective drive limits at the same time, if all of these actuators are given a drivable amount at which these actuators can be mechanically driven within the control period at the present time, None of these actuators are controlled, which is inconvenient for optimally adjusting the plate shape of the rolled material.

The types of the drive limit of the actuator include a speed limit restricted by the drive speed and a mechanical limit restricted by the structure of the actuator. The speed limit is a state in which the actuator cannot complete the driving of the control amount given by the calculation within the control cycle. For example, when a control amount related to a drive command of 10 mm is given to an actuator having a maximum drive speed of 0.8 mm / sec in a control cycle of 3 seconds, the actuator falls into the above-mentioned speed limit.

Further, the mechanical limit means a state in which the actuator cannot be driven due to the structure of the actuator. For example, an actuator whose mechanically drivable range is ± 65 mm is +65 mm from the current position.
The above mechanical limit is reached when driving a distance of up to mm or -65 mm and no further driving is possible except in the opposite direction. At this time, once the actuator reaches the mechanical limit, the actuator often repeatedly reaches the mechanical limit even by the control amount given by the recalculation. Since the mechanical limit is an absolute limit, it cannot be treated in the same way as other limits. Under such circumstances, it is useless to deal with the problem by correcting the gain of the control system as in the conventional case. Therefore, it is necessary to prioritize that the above absolute limit is quickly fixed to the control amount related to the drive limit and excluded from the control amount calculation target.

Therefore, an object of the present invention is to enable even when a plurality of actuators reach their respective driving limits at the same time,
Provided is a method for adjusting the plate shape of a rolled material by a rolling mill, which is capable of appropriately adjusting the plate shape of the rolled material without fixing the control amounts of all of these actuators to the controlled values required for the respective drive limits at the same time. Especially.

[Means for Solving the Problems]

In order to achieve the above object, the main means adopted by the present invention, the gist of which is to define the plate shape in the plate width direction of a rolled material rolled by a rolling mill composed of a plurality of rolls combined in multiple stages When adjusting by controlling a plurality of actuators acting on the roll, the degree of change of the plate shape with respect to the control amount of the actuator is expressed, and the control of each actuator is performed based on the influence coefficient preset for each actuator. In the method of adjusting the strip shape of a rolled material in which a control function for calculating the amount is calculated, and each actuator is controlled by this control function at each predetermined control cycle, the control function is composed of the control amounts of all the actuators. The actuator control amount included in the calculated control function drives the actuator. At least one of the certain actuators is controlled according to a predetermined priority order when one of the certain actuators that exceeds the limit appears, or when a plurality of the certain actuators appear. The control amount of is fixed to the control amount that depends on the drive limit of the actuator,
Rolling mill according to the point that a new control function consisting of the control amounts of all the actuators except the actuator with the fixed control amount is calculated based on the influence function within the control cycle Is a method for adjusting the plate shape of the rolled material.

It should be noted that the above-mentioned predetermined priority is that the actuator related to the mechanical limit is prioritized over the actuator related to the speed limit, or is set for each specific pattern related to the plate shape of the rolled material. Further, the priority order of the actuators related to the speed limit and the priority order of the actuators related to the mechanical limit are set for each specific pattern related to the plate shape of the rolled material, or The priority order of the actuators related to the speed limit and the priority order of the actuators related to the mechanical limit are a combination of the priority order set for each specific pattern related to the plate shape of the rolled material and the preset priority order. May be set by.

On the other hand, in the method of the present invention, it is possible to determine in advance a plurality of actuators to which the control amount should be fixed at the same time according to the types of these actuators. Depending on the type, a plurality of patterns may be determined in advance for each specific pattern relating to the plate shape of the rolled material.

[Action]

According to the method of the present invention, the above-mentioned control function is composed of the control amounts of all the actuators, and the above-mentioned one actuator is such that the control amount of the certain actuator included in the calculated control function exceeds the drive limit of the certain actuator. When they appear, the control amount of the above actuator is
Alternatively, when a plurality of the certain actuators appear, the control amount of at least one of the certain actuators is fixed to the control amount related to the drive limit of the actuator according to a predetermined priority. Therefore, all of the actuators appearing in the plurality are not fixed to the control amounts for the respective drive limits at the same time. Next, a new control function that consists of the control amounts of all actuators except the actuator whose fixed control amount is fixed is calculated based on the influence coefficient within the control cycle, and the new control function is calculated. By this, all the actuators are controlled except for the actuator whose control amount is fixed, and the plate shape of the rolled material is adjusted. Further, when a plurality of the other actuators appear such that the control amount of the other actuators included in the calculated new control function exceeds the drive limit of the other actuators, the other actuators are Depending on the priority, the same method as described above is repeated within the control cycle until, for example, an actuator whose calculated control amount exceeds the drive limit does not appear. Therefore, while the actuators that were initially limited by the drive limit and are fixed in order according to the priority order, a new control function is constantly recalculated. The plate shape is adjusted appropriately.

〔Example〕

Embodiments embodying the present invention will be described below with reference to the accompanying drawings to provide an understanding of the present invention. The following examples are specific examples of the present invention and do not limit the technical scope of the present invention.

1 is an overall configuration diagram showing a rolling mill and a plate shape adjusting device to which an embodiment of the method of the present invention shown in FIG. 1 is applied. FIG. 2 is a front view showing a schematic configuration of the rolling mill shown in FIG. FIG. 3 is a flowchart showing a processing procedure for adjusting the plate shape of the rolled material by the plate shape adjusting apparatus of FIG.

As shown in FIG. 1, the rolling mill 20 according to the present embodiment includes work rolls 2 arranged in a pair in the upper and lower direction to roll a rolled material E as a raw material into a rolled material F of a thin plate, and respective work rolls. A taper roll 3 as a first intermediate roll provided in contact with the outer periphery behind the roll 2; a bender roll 4 as a second intermediate roll provided in contact with the outer periphery behind the taper roll 3; It consists of a backup roll 5 arranged in contact with the outer periphery of the vendor roll 4 further behind 20
It is configured as a corrugated rolling mill.

Then, above the upper backup roll 5 above,
The crown actuators 12 are arranged at a plurality of positions (four positions in this embodiment) in the axial direction. Each crown actuator 12 is independently driven, and by pressing the outer peripheral surface of the backup roll 5 at the deployment position, the axial deflection of the work roll 2 is corrected and the heat generated in the work roll 2 is corrected. Axial deformation called a crown is corrected to adjust the plate shape of the rolled material F.

Further, the upper and lower taper rolls 3 are arranged so that their taper directions are opposite to each other, and a lateral actuator 13 is provided at each axial end on the small diameter side. This lateral actuator 13 drives the rolled material F by axially moving the taper roll 3 in and out of the positions where all the rolls 2, 3, 4, and 5 are installed.
The plate shape at the end of the plate in the axial direction is adjusted.

Then, the rolls 2, 3, 4, 5 are tilted in the axial direction to a common roll bearing portion (not shown) on which the rolls 2, 3, 4, 5 on the upper side or the lower side are axially supported. Two tilt actuators 14 are provided for the left and right pairs. By driving the tilt actuator 14, the rolled material F is
For example, the elongation rate at one end in the plate width direction is higher than that at the other end.

Further, below the lower backup roll 5, a push-up actuator 11 for pushing up the backup roll 5 is provided in order to adjust the plate thickness of the rolled material F. The push-up actuators 11 are arranged at respective lower positions corresponding to four different positions in the roll axial direction where the crown actuators 12 are arranged, and the push-up actuators 11 are integrally driven with the same drive amount. It is designed to be driven.

A plate shape detector 6 for detecting the elongation (I-unit) distribution (plate shape) of the rolled material F in the plate width direction is provided downstream of the rolling mill 20 in the rolled material conveyance direction. There is. The plate shape detector 6 is composed of a plurality of plate shape detection sensors (not shown) which are arranged by being divided in the plate width direction and which detect the elongation at the position. A strip thickness gauge 7 and a strip thickness gauge 8 are provided on the upstream side and the downstream side of the rolling mill 20 in the rolled material conveying direction, respectively.

The detection signals a and b relating to the plate thickness of the rolled materials E and F detected by the plate thickness gauges 7 and 8 are input to the plate thickness adjusting unit 9.

The plate thickness adjusting unit 9 controls the push-up actuator 11 based on the detection signals a and b before and after rolling from the plate thickness gauges 7 and 8 and the target plate thickness signal c of the rolled material F which is preset and input. The amount is calculated, and the control signal e related to the calculated control amount is output.

The detection signal f relating to the plate shape of the rolled material F detected by the plate shape detector 6 is input to the plate shape adjusting unit 10.
The plate-shaped adjuster 10, based on the target plate shape signal G of the detection signal f and a preset input rolled material F from the plate-shaped detector 6, the driving amount [Delta] x ₁ of each crown actuators 12 ~ Δx ₄ (Fig. 2), each lateral actuator
The drive amounts Δx ₅ and Δx _{6 of} 13, the drive amounts Δx ₇ and Δx _{8 of the} tilt actuators 14, and the control signal e for the drive amount of the push-up actuator 11 output from the plate thickness adjusting unit 9.
The correction drive amount added to is calculated and the control signals q, p, r, d corresponding to these drive amounts are output. That is, the plate shape adjusting device 1 that adjusts the plate shape of the rolled material F by driving and controlling the above actuators is configured around the plate thickness adjusting unit 9 and the plate shape adjusting unit 10.

By changing the drive amount of the crown actuator 12, the lateral actuator 13, and the tilt actuator 14 by adding the control signal d relating to the corrected drive amount to the control signal e relating to the drive amount of the push-up actuator 11, A control signal corrected in consideration of the plate thickness change that occurs is obtained, and the push-up actuator 11 is drive-controlled based on this control signal. Similarly, the upper backup roll 5, the upper and lower taper rolls 3 and the bearings that support the rollers are supported by the crown actuators 12, 12, which are driven according to the control signals q, p, r, respectively. The lateral actuator 13 and the tilt actuator 14 control their respective positions to adjust the plate shape of the rolled material F.

Further, the plate shape adjusting device 1 is provided with a memory (not shown) for storing an evaluation function φ for evaluating the plate shape and the plate thickness of the rolled material F rolled by the rolling mill 20. The evaluation function φ is defined as the following expression (1).

δε _i = g · (ε _ri −ε _Ti ) + Δε _i (2) In equations (1) and (2), W _i : weight for shape evaluation at the position of the i-th plate shape detection sensor in the plate width direction Δh _k : Indicates the amount of change in plate thickness due to the driving of the kth actuator. However, as for the actuator number k, the two lateral actuators 13 related to the roll shift mechanism are k = 1,2,
Four crown actuators related to crown adjusting mechanism
12 is k = 3 to 6, and two tilt actuators 14 related to the roll tilting mechanism are k = 7 and 8.

W _t : Weight related to plate thickness n: Total number of plate shape detection sensors within the plate width g: Control gain ε _ri : Plate shape to be adjusted detected at the position of the i-th plate shape detection sensor. Is realized in the form of a so-called elongation difference ratio, which is defined as the difference between the elongation ratio in the rolling direction of the plate actually measured by the plate shape detection sensor and the elongation ratio at the least stretched position in the plate width. Ε _Ti : Target plate shape that is preset at the position of the i-th plate shape detection sensor, and is generally preset by a person in the form of the above-mentioned elongation difference ratio Δε _i : Predicted plate shape change amount defined by the equation (3) The evaluation function φ appropriately controls all actuators to appropriately adjust the plate shape while suppressing the plate thickness variation of the rolled material F. The minimum is 2 as shown in equation (1).
Multiplication is applied.

The evaluation function φ is a function of a predicted plate shape change amount Δε _i and a plate thickness change amount Δh _k described later. Therefore, in order to determine the control amount of each actuator that minimizes the evaluation function φ, the relationship between the plate shape change amounts Δε _i and Δh _k and the control amount Δx _{j of the} actuator is expressed by the following equation (3) and It is modeled in advance as shown in equation (4).

When the j-th actuator is driven and controlled, the influence coefficient model of the plate shape change amount Δε _i that predicts how much the plate shape detected by the i-th plate shape detection sensor is changed by this control amount Δx _j is ( 3) is defined by the equation. still,
The symbol and suffix for the actuator number is J or
j, K, or k will be used below, but this is conveniently used to perform the summation operation in each equation.

However, α _ij : i by the driving of the jth actuator
Influence coefficient (I-unit / mm) on the plate shape change amount at the position of the th plate shape detection sensor Δx _j : Control amount of the jth actuator (mm) Further, the plate of the rolled material F is driven by the actuator. The influence coefficient model of the plate thickness change amount Δh _j that predicts how much the thickness changes is defined as in equation (4).

Δh _j = β _j × Δ x _j (4) where β _j is the coefficient of influence on the plate thickness change due to the driving of the j-th actuator. The values of the above-mentioned influence coefficients α _ij and β _j are obtained in advance by experiments and It is set in the impact coefficient model.

Then, when the evaluation function φ is minimized, the plate shape and the plate thickness of the rolled material F are optimally adjusted, and the condition for minimizing the evaluation function φ is given by the following equation (5).

By solving the equation (5) with respect to Δx _k , the control amounts Δx _{1 to} Δx ₈ of each actuator for appropriately adjusting the plate shape and the plate thickness can be obtained.

Then, by substituting the equations (1) to (4) into the equation (5), the following equation (6) is obtained.

In the equation (6), δ _i , _j means Kronecker's delta, and when i = j, δ _i , _j = 1 and i ≠ j, δ _i , _j = 0.

When the expression (6) is displayed in a matrix, it is expressed as the following expression (7).

[A _KJ ] · [ΔX _J ] = g · [B _K ] ... (7) However, each element in the matrix of the formula (7) is as shown in the following formula. The capital letters of the subscripts attached to the symbols (A, ΔX, B) indicate the entire matrix, and the lower case letters indicate the elements of the matrix.

ΔX _j = Δx _j (10) Expanding equation (7) gives [ΔX _J ] = g · [A _KJ ] ⁻¹ · [B _K ]… (11). In the equation (11), [A _KJ ] ^-1 is called a control matrix, and is an inverse matrix composed of the elements A _{kj of the} equation (8) regarding the influence coefficients α _ij and β _j .

[B _K ] is called the state vector, and the detected plate shape ε _ri
Of equation (9) regarding the difference between the target and plate shape ε _Ti
It _{consists of} B _k . Also, [ΔX _J ] is called an increment vector, and is calculated as the product of the control matrix [A _KJ ] ⁻¹ and the state vector [B _K ]. This increment vector [Δ
X _J ] consists of the element ΔX _{j in} Eq. (10), and this element ΔX _j is calculated as the control amount ΔX _j for driving each actuator.

That is, the above equation (11) is the control amount Δ of the actuator.
A control set for each actuator for calculating the control amount of the actuator based on the influence coefficients α _ij and β _j , which represents the degree of the plate shape change amount Δε _i or the plate thickness change amount Δh _j with respect to x _j . Is a function.

In such a rolling mill 20, when the strip shape detected in the initial stage of rolling of the strip F is largely different from the target strip shape, the control amount Δx _{k of the} actuator calculated from the equation (11) is calculated. May be too large and the drive amount of this actuator may not reach the control amount within the control cycle.

Therefore, in the device of this embodiment,
The calculated control amount Δx _k is compared with the drivable amount Δx _kmax that can be mechanically driven within the control cycle at present, and when the control amount Δx _k exceeds the drivable amount Δx _kmax (|
Δx _k |> | Δx _kmax |), it is determined that the actuator exceeds the drive limit. Here, the drivable amount Δx _kmax is given as the control amount at this time to the actuator that exceeds the drive limit.

Then, after the elements relating to the actuators exceeding the drive limit are removed from the control matrix, the control matrix [ _AK-1 , _J-1 ] ^-1 is calculated. Using this control matrix [A _K-1 , _J-1 ] ^-1 , the control amounts of the actuators other than the above-mentioned drive limit actuators are calculated again.

However, the state vector [B
_K-1 ] is calculated instead of the plate shape ε _ri (Equation (9)), which is affected by giving the drivable amount Δx _kmax as the control amount to the actuator that exceeds the drive limit. The correction plate shape ε ^* _ri considering the influence is applied to the equation (9). The correction plate shape ε ^* _ri is expressed by the following equation (12).

[epsilon] ^* _ri = [epsilon] _ri + [alpha] _ik * [ _Delta ] x _kmax (12) where, k: actuator number for which the calculated control amount exceeds the drive limit. When a plurality of exceeded actuators appear, priority is preset for all the actuators in order to select one of the actuators whose control amount is fixed to the drivable amount.

Table 1 below shows the priorities set in advance for the actuators. In the table, the actuator with the actuator number (k) located on the left side has the higher priority. The same applies to the tables below.

Therefore, the control procedure of the actuator by the plate shape adjusting apparatus 1 will be described below in the order of steps S1, S2, ... With reference to the flowchart of FIG. The contents of the flow chart are stored in advance as a sequence program in, for example, a memory of the plate shape adjusting device 1.

First, the rolled material E on the raw material side is rolled as the rolled material F on the output side by the pair of work rolls 2 of the rolling mill 20. The strip shape detector 6 detects the strip rate distribution in the sheet width direction of the rolled material F (S1). In this case, the rolled material F has a high elongation rate in the portion extending in the plate width direction,
The elongation of the stretched part is detected low.

Then, an actuator that can be used at present is selected (S2). In this step, at the time of initial setting,
All actuators are set to be usable.

Next, for all the actuators, based on the influence coefficients α _ik and β _k previously determined by the combination of these actuators, the control matrix [A
_KJ ] ^-1 is calculated using the equation (8) (S3).

In the subsequent step S4, if the control amount given to an actuator exceeds the drive limit of the actuator as described later, it is affected by fixing the control amount of this actuator to the control amount Δx _kmax which is related to the drive limit. The plate shape ε _ri to be corrected is calculated as the corrected plate shape ε ^* _ri by the equation (12). Here, there can be no actuator that exceeds the drive limit, so the plate shape ε _ri detected by the plate shape detector 6 is not subjected to correction calculation, and the value as it is is used for the next step S5.

In this step S5, the state vector [B _k ] is calculated by the equation (9) based on the difference between the detected plate shape ε _ri and the target plate shape ε _Ti and the influence coefficient α _ik. .

Then, from the calculated state vector [B _K ] and the control matrix [A _KJ ] ^-1 , the control amount Δx _{k of} each actuator is calculated by the equation (11) as an increment vector of the product (S6 ).

Therefore, the control amount Δx _{k of} each actuator calculated above
When these actuators are driven by, the actuators may exceed the drive limit of these actuators due to the control amount Δx _k . The so-called actuator is subject to its drive limit.

That is, the calculated control amount Δx _k and the movable amount Δx _kmax that the actuator can drive within the control cycle are compared for each actuator, and the control amount Δx _k is larger than the drivable amount Δx _kmax. Is present (S7), the processing procedure proceeds to step S8.

In step S8, the number of actuators that reach the drive limit is first checked. If the number of actuators is 1, the processing procedure proceeds directly to the next step S9. On the other hand, when the number of the actuators is 2 or more, only the actuator having the highest priority among them is selected according to the priority set in advance for each actuator as described above.

The control amount Δx _k of the selected actuator is fixed to the drivable amount Δx _kmax that depends on the drive limit of this actuator (S9). For example, when the actuators that have reached the drive limit are the lateral actuator 13 (k = 1), the crown actuator 12 (k = 3), and the tilt actuator 14 (k = 7), the preset priority order is set. Highest lateral actuator 13 (k
The control amount of = 1) is fixed to the drivable amount. This lateral actuator 13 is not selected as an actuator that can be used in step S2 and is not subject to the following control amount calculation (S3 to S6).

Crown actuator 12 and tilt actuator 1
3 and other remaining actuators go through step S2
Again, the control matrix [A _K-1 , _J-1 ] ^-1 is subject to calculation.

That is, when the control matrix [A _KJ ] ^-1 is calculated in step S3, the elements relating to the lateral actuator 13 in this control matrix [A _KJ ] ^-1 are deleted and the control matrix relating to the elements relating to the remaining actuators is deleted. [A _K-1 , _J-1 ] ^-1 is calculated.

Subsequently, in step S4, the correction plate shape ε ^* _ri (= _εri +) of the plate shape _εri influenced by fixing the lateral actuator 13 to the movable amount Δx _kmax
α _ik .Δx _kmax ) is calculated, and this corrected plate shape ε ^* _ri is used for calculating the above state vector [B _K-1 ] instead of the detected plate shape ε _ri (S5).

Then, the control matrix [ _AK-1 , _J-1 ] calculated under the condition that the control amount of the lateral actuator 13 is fixed.
Since ^-1 and a state vector [B _K-1] according to the control amount of the remaining actuators [[Delta] X _K-1] is computed (S6).

Therefore, it is determined whether or not the remaining actuators calculated above have reached the respective drive limits (S
7), Lateral actuator with fixed control amount 1
If the actuators other than 3 (k = 1) have reached the drive limit this time, the same steps as the previous time (S8, S9, S2 to S7) are repeated. This repeating step is executed until there is no actuator at the drive limit.

When the actuators that reach the drive limit disappear (S7), the value of the control vector calculated at this time is output to each actuator as a control signal related to the control amount (S10), and based on these control signals. All actuators are drive-controlled simultaneously (S11).

In the shape adjusting device 1, when the current control cycle has elapsed, the contents of the control amount calculation are reset, and in the next control synchronization, the plate shape and the plate thickness are newly adjusted from the initial setting state. It

It should be noted that in the above-described embodiment, regardless of the type of drive limit such as the speed limit or mechanical limit of the actuator,
Although suitable priorities are preset for all actuators, the priorities can be set in consideration of the types of drive limits.

For example, the plate shape adjusting device 1 is provided with a judging means for judging the type of the drive limit when the actuator is in the drive limit, and when, for example, two actuators which are in the drive limit appear. The determination means determines the types of drive limits of these actuators, and the actuators subject to mechanical limits, which are absolute limits, are given priority over actuators subject to speed limits, and the control amount is set to the driveable amount. It is a method of fixing. By this, when an actuator that reaches the mechanical limit appears, it is attempted to avoid repeatedly applying the mechanical limit to the actuator due to the result of the control amount calculation again.

In addition, it is preferable that the drive limit of the actuator be set in advance for each type of actuator.

This is because, after the type of the drive limit is determined by the determination means, first, the actuator that is subject to the mechanical limit is selected in preference to the actuator that is subject to the speed limit, and the actuator that is subject to the mechanical limit is selected from among the actuators that are subject to the mechanical limit. The control amount of the actuator with the highest priority set in advance is fixed to the drivable amount.

Therefore, the following table 2 shows the order of priority of actuators set in advance for each type of drive limit.

Now, suppose that the actuators with k = 2,3 simultaneously reach the mechanical limit and the actuators with k = 1,4 simultaneously reach the speed limit. In this case, the control amount of the actuator with k = 2 is Is fixed to the drivable amount and excluded from the control amount calculation. Furthermore, as a result of performing the control amount calculation again for the remaining actuators, if no actuators that meet the mechanical limit appear here and the actuators with k = 3,1 reach the speed limit, regarding the speed limit, The actuator of k = 3 having a higher priority is excluded from the control amount calculation in the same manner as above. Therefore, according to the embodiment method as described above, it is possible to prevent the actuator from repeatedly hitting the mechanical limit by excluding the actuator once reaching the mechanical limit from the control amount calculation. This makes it possible to effectively control the remaining drivable actuators.

On the other hand, according to the method in which the priorities of the actuators that are fixed in the control amount and excluded from the control amount calculation are set in advance in a fixed manner as shown in the above-described respective embodiments, it is possible that When the difference between the detected plate shape and the target plate shape is extremely large, problems such as plate breakage may occur depending on the plate shape at that time. That is, the control amount calculated for each actuator in order to bring the detected plate shape closer to the target plate shape is large at the initial stage of the rolling start. However, since the actuator having the higher priority is fixed to the drivable amount earlier, the difference between the calculated control amount of the actuator and the drivable amount is relatively large.

Therefore, there is provided a recognizing means for classifying the problematic shape pattern appearing in the plate shape into a plurality of shape patterns in advance and recognizing which of the classified shape patterns the detected plate shape belongs to. The above-mentioned problems can be solved by setting the above-mentioned priority order for each shape pattern. In this case, as the shape pattern, a selvage pattern in which both ends in the plate width direction of the rolled material F extend, a half-stretch pattern in which the one end in the plate width direction extends and the central part in the plate width direction Are categorized into three types of medium stretch patterns.

Then, as the above-mentioned recognizing means, a method based on numerical calculation is adopted here. For example, the elongation rate of one end portion in the plate width direction of the rolled material F detected by the plate shape detector 6 is f _e1 ,
Letting the elongation rate at the other end be f _e2 and the elongation rate at the center in the plate width direction be f _c , the above-mentioned classified shape patterns can be defined by the following equations.

1. Ear wave pattern (f _e1 + f _e2 ) / 2 ＞＞ f _c … (13) 2. Half stretch pattern (f _e1 ＋ f _e2 ) ＞ 100… （14） 3. Medium stretch pattern (f _e1 ＋ f _e2 ) / 2 << f _c (15) Further, the above-mentioned priority order of actuators is preset for each shape pattern as shown in Table 3 below.

The priorities of the actuators set in advance for each shape pattern are set to be lower as the actuators that can be adjusted to eliminate the shape patterns and bring them closer to the target plate shape.

Therefore, when the plate shape of the rolled material F is detected by the plate shape detector 6, the one end, the other end, and the like included in the plate shape,
The elongations f _e1 , f _e2 , and f _{c of the} central part are used for the numerical calculation by the equations (13) to (15). By this, it is recognized which of the above-mentioned shape patterns the detected plate shape belongs to.

Then, for example, it is recognized that the detected plate shape belongs to the intermediate stretch pattern, and at this time, three actuators that have reached the drive limit appear at the same time, and these actuator numbers k are k = 2,4. , 5, the control amount of the fourth crown actuator 12 having the actuator number k is fixed to the above drivable amount, and this crown actuator 12 is not used for the repeated control amount calculation. As a result, the actuator that can adjust the plate shape more appropriately remains, and the control amount is calculated again, so that the problematic shape pattern is eliminated more quickly.

In this embodiment, the priority order of the actuators is preset for each of the shape patterns, but the priority order of the actuators due to the mechanical limit and the priority order of the actuators due to the speed limit are shown in Table-3, for example. For each of the actuators subject to the mechanical limit or the velocity limit depending on which shape pattern the current plate shape belongs to, the actuator subject to the mechanical limit is set to If the control amount is fixed prior to the limit actuator, the plate shape can be adjusted more accurately.

Further, the priority order of the actuators related to the mechanical limit and the priority order of the actuators related to the speed limit may be set by a combination of the priority order set for each shape pattern and the preset priority order. it can.

For example, the priority of actuators related to mechanical limit is set to lateral actuator 13, crown actuator 1
2, the tilt actuator 14 is set in advance, and the priority order of the actuators that affects the speed limit is set for each shape pattern. If the plate shape shape pattern at that time is a medium extension pattern, the crown actuator 12 Lateral actuator 13 Tilt actuator 14 Tilt actuator 14 Lateral actuator 13 Crown actuator 12 If it is a one-sided extension pattern, Lateral actuator 13 Crown actuator 12 Tilt actuator 14 is set in order from the top if it is an ear wave pattern.

Then, by recognizing the shape pattern, when the current plate shape is an ear wave pattern and there is no actuator that imposes a mechanical limit, and the actuators that impose a velocity limit are the lateral actuator 13 and the tilt actuator 14, The control amount of the lateral actuator 13 is fixed.

At this time, if there is an actuator having a mechanical limit, this actuator can be prioritized regardless of the shape pattern. On the contrary, the priority order of the actuators related to the mechanical limit may be set for each shape pattern, and the priority order of the actuators related to the speed limit may be set in advance.

On the other hand, when a plurality of actuators simultaneously reach their drive limits, if the control amount is fixed one by one according to the various predetermined priorities as described above, the drive limits are reached at the same time. When the number of actuators is large, the calculation time especially increases. Further, depending on the type of actuator, there are a plurality of actuators whose control amounts are always fixed when the control amount calculation is repeatedly executed. If the control amounts of such actuators are fixed one by one, the calculation time will be wasted.

Therefore, when it is clear that such a plurality of actuators are present, the control time of the plurality of actuators is fixed at the same time, so that the waste of the calculation time can be eliminated.

For example, when the detected plate shape is an extremely large medium stretch pattern, the lateral actuator 13 (k = 1,
Experience has shown that 2) depends on the drive limit of both units. In the case of such a shape pattern,
Even if the control amount of one of the lateral actuators 13 (k = 1) is fixed, the driving limit of the other lateral actuator (k = 2) is applied next time due to the calculation of the control amount again. Therefore, in this case, when the two lateral actuators reach the drive limit, by fixing the respective control amounts at the same time, it is possible to prevent the calculation time from being wasted.

Then, in the case where the control amount can be fixed at the same time depending on the type of the actuator, the shape pattern recognition method may be applied. For example, the actuators with actuator numbers k = 1, 2, and 3 are simultaneously subjected to their respective drive limits, and the shape patterns (ear wave pattern, middle stretch pattern, half stretch pattern) recognized for the plate shape detected at that time Among the above actuators, the control amount of the actuators of k = 1, 2 is fixed at the same time, or the control amounts of the actuators of k = 1, 2, 3 are fixed at the same time. This allows the actuator to be controlled more precisely.

As the recognition means for recognizing the shape pattern of the plate shape, a numerical calculation method has been applied so far, but the invention is not limited to this, and for example, a neural network system may be used as the recognition means.

In this case, each of the classified shape patterns is used as teacher data, and the plate shape data from the plate shape detection sensor corresponding to each shape data is used as learning input data to learn the connection weight of this network in advance. Let's decide. When the shape pattern recognition process is performed, the plate shape data detected at that time is input to the neural network and is recognized as belonging to any of the shape patterns based on the determined connection weight.

EFFECTS OF THE INVENTION According to the present invention, the plate shape in the plate width direction of a rolled material rolled by a rolling mill composed of a plurality of rolls combined in multiple stages is controlled by a plurality of actuators acting on the rolls. When adjusting by, the degree of change of the plate shape with respect to the control amount of the actuator is expressed, and the control function for calculating the control amount of each actuator is calculated based on the influence coefficient preset for each actuator. , In the plate shape adjusting method for a rolled material in which each of the actuators is controlled at a predetermined control cycle by this control function, the control function includes control amounts of all the actuators, and the actuators included in the calculated control function One of the above actuators whose control amount exceeds the drive limit of the actuator is output. When it appears, the control amount of the certain actuator is applied, or when a plurality of the certain actuator appears, the control amount of at least one of the certain actuators is applied to the drive limit of the actuator according to a predetermined priority. A new control function that is fixed to the control amount and consists of the control amounts of all actuators except the actuator with the fixed control amount is calculated based on the influence function within the control cycle. A plate shape adjusting method for a rolled material using a rolling mill is provided.

As a result, even if a plurality of actuators reach their respective drive limits at the same time, at least one of them will be controlled according to a predetermined priority order without fixing the control amounts of all of these actuators to the control amounts of their respective drive limits at the same time. It is possible to fix the control amount to the drive limit one by one.

Therefore, the plate shape of the rolled material can be adjusted appropriately.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing a rolling mill and a plate shape adjusting device to which an embodiment of the method of the present invention is applied, FIG. 2 is a front view showing a schematic configuration of the rolling mill of FIG. 1, and FIG. It is a flow chart which shows the processing procedure concerning adjustment of the plate shape of the rolled material by the plate shape adjusting device of FIG. [Description of symbols] 1 ... Plate shape adjusting device 2 ... Work roll 3 ... Tapered roll 4 ... Bender roll 5 ... Backup roll 6 ... Plate shape detector 10 ... Plate shape adjusting unit 12 ... Crown Actuator 13 …… Lateral actuator 14 …… Tilt actuator 20 …… Rolling mill

Continued Front Page (72) Eiji Yoshida Inventor Eiji Yoshida 1-84-301 Kaminoya, Suma-ku, Kobe-shi, Hyogo

Claims (7)

[Claims] 1. When adjusting a plate shape in a plate width direction of a rolled material rolled by a rolling mill composed of a plurality of rolls combined in multiple stages by controlling a plurality of actuators acting on the rolls, A control function for calculating the control amount of each actuator is calculated based on the influence coefficient preset for each actuator, which represents the degree of change in the plate shape with respect to the control amount of the actuator. In the method of adjusting the strip shape of a rolled material, which controls each actuator at every predetermined control cycle, the control function comprises control amounts of all actuators, and the control amount of an actuator included in the calculated control function is the control amount. When one of the above actuators that exceeds the drive limit of the actuator appears, the above If a certain control amount of an actuator appears, or when a plurality of the above-mentioned certain actuators appear, fix the control amount of at least one of the above-mentioned actuators to the control amount related to the drive limit of that actuator according to a predetermined priority. , Characterized in that a new control function consisting of the control amounts of all the actuators except the actuator whose control amount is fixed is calculated based on the influence function within the control cycle. Method for adjusting plate shape of rolled material by rolling mill. 2. The method for adjusting the strip shape of a rolled material by a rolling mill according to claim 1, wherein the predetermined priority is to give priority to an actuator that is subject to a mechanical limit over an actuator that is subject to a speed limit. 3. The method for adjusting the strip shape of a rolled material by a rolling mill according to claim 1, wherein the predetermined priority is set for each specific pattern relating to the strip shape of the rolled material. 4. The predetermined priority order is set for each of the specific patterns related to the plate shape of the rolled material, and the priority order of the actuators related to the speed limit and the priority order of the actuators related to the mechanical limit are set, respectively. The method for adjusting the plate shape of a rolled material by the rolling mill according to claim 1, wherein 5. The predetermined priority order is set for each of the specific patterns related to the plate shape of the rolled material, that is, the priority order of the actuators subject to the speed limit and the priority order of the actuators subject to the mechanical limit are set. The method for adjusting the plate shape of a rolled material using a rolling mill according to claim 1, wherein the priority is set by a combination of a priority and a preset priority. 6. The method for adjusting the plate shape of a rolled material by a rolling mill according to claim 1, wherein a plurality of actuators for which the control amount is to be fixed at the same time are determined in advance according to the types of these actuators. . 7. A plurality of actuators for which the control amount should be fixed at the same time are determined in advance for each specific pattern relating to the plate shape of the rolled material according to the type of these actuators. A method for adjusting the plate shape of a rolled material by the rolling mill described.