JPH0754057A - Method for controlling tension of long size material - Google Patents

Abstract

PURPOSE:To prevent to affect on tention between the other rolls by result of tension control between specified rolls of plural transporting rolls with which a long size material is transported. CONSTITUTION:In a tension control method for transporting a belt-like long size matter 1 with the transporting rolls 2a, 2b 2c, 2d while controlling tension T1, T2, T3 between the rolls at a specified value, for example, when the tension of the long size material 1 between the transporting rolls 2b, 2c is controlled, the corrected value of speed command that is given to the speed controllers of the transporting rolls 2b, 2c is varied so that the directions of forces that are applied to the long size material with the transporting rolls 2b, 2c are mutually canceled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tension control method for conveying a long object such as a steel plate while maintaining a predetermined tension.

[0002]

2. Description of the Related Art FIG. 9 is a block diagram showing a conventional tension control device. A conveyor roll (actually, a large number of conveyor rollers) that conveys a strip-shaped and long object (hereinafter referred to as “long object”) 1 such as a steel plate is provided here.
Conveyor roll 2 showing only four a, 2b, 2c, 2d
a is the entrance side and the transport roll 2d is the exit side) are arranged at predetermined intervals. The roll may be in the form of a pair of upper and lower pinch rolls as in the example of FIG. 9, or a long object may be wound around a drive roll at a predetermined winding angle without pinching. is there. Further, tension sensors 3a, 3b, 3c for detecting the tension of the elongated object 1 are provided between the transport rolls 2a, 2b, 2c, 2d. Motors 4a, 4b, 4c and 4d as rotation driving sources are connected to the respective transport rolls 2a to 2d, and the speed control devices 5a and 5d are connected to the respective motors.
Each of b, 5c, and 5d is connected. To this end, tension control devices 6a, 6b and 6c are provided, and subtractors 7a, 7b and 7c are connected to the respective input parts thereof. Each of the subtractors 7a to 7c is Is entered.

Further, adders 8a, 8b and 8c are provided at the input portions of the speed control devices 5a to 5d, respectively. Applied to the contact.

[0004] Based on the tension detection values T ₁ , T ₂ and T ₃ by the tension control devices 6a, 6b and 6c. Controls the rotation of each of the motors 4a to 4d, and the long object 1
The tension at each position is controlled so as to be equal to the tension set value.

[0005]

In controlling the tension of a strip-shaped long object, it is necessary to control the tension between the transport rolls to a predetermined value. The reason is as follows. (A) When excessive tension is applied to a long object. When a tension exceeding the limit of strength is applied, plastic deformation occurs, causing changes in thickness, width, thickness, etc., and further causing fracture. In a continuous strip annealing furnace, an excessive force is applied in the width direction of the strip to generate a heat buckle or the like. In the case of a continuously cast slab that is in the process of solidification, the surface solidified layer is cracked, the unsolidified portion inside the slab leaks, and a flaw occurs on the surface. (B) When an excessive tension is applied to a long object. An object to be conveyed (long object) laterally flows (walks) at the conveying roll portion, and stable conveyance cannot be performed. In the case of a strip or the like, the strip may hang down between rolls and may come into contact with the bottom of the apparatus or the like to scratch the strip surface.

For this reason, it is necessary to arbitrarily control the magnitude of tension between specific rolls to a value most suitable for the section. Note that, in FIGS. 9 and 10, the transport rolls and the speed control device correspond to each other in a one-to-one correspondence, but there may be a case where one speed control device drives a plurality of transport rolls. Further, a plurality of transport rolls each having a speed control device may be group-controlled. Note that, regarding this type of technology, there are, for example, JP-A-57-9832, JP-A-57-85755, JP-A-5-70843 and JP-A-4-329835.

[0008]

However, in the above-mentioned prior art, when the long object is being conveyed, the driving force is changed at any one of the plurality of conveying rolls. Then, this influence also changes the tension between the transfer rolls other than the control target at the same time, and the responsive tension control could not be obtained. For example, as shown in FIG. 11, it can be seen that interference (disturbance) occurs on the T ₁ and T ₃ sides with respect to the step response of ΔT ₂ and affects the roll that is not the control target. An object of the present invention is to make it possible to prevent the result of tension control between specific rolls of a plurality of transport rolls that are transporting a long object from affecting the tension between other rolls. It is to provide a tension control method for a scale object.

[0009]

[Means for Solving the Problems]
In order to achieve this, the present invention allows a long object to
To convey while controlling the tension between two rolls to a predetermined value
In the method of controlling tension, the long object between specific rolls
I want to control body tension so that it does not interfere with tension between other rolls
Each of the rolls located on both sides between the rolls is
The directions of the forces exerted on the long objects are set to cancel each other.
Correction of speed command given to the speed controller of the rolls on both sides
I am trying to change the value. Speed control of the roll
The correction value of the speed command given to the device is the output of the tension control device.
Between the specific rolls on the upstream side (the upstream side in the transport direction
To m-th roll) speed command to the speed controller
When used as a correction value for
To the speed control device of the m + 1th roll from the upstream side of
Is the output of the tension control device, _{m + 1}・ P_m× V_{0m + 1} ²) / (Α _m・ P_{m + 1}・ V_{0 m}) Alternatively, the output of the tension control device can be fed downstream between specific rolls.
Side roll (m + 1th row from the upstream side in the transport direction)
Used as a correction value for the speed command given to the speed controller
If there is a roll on the upstream side,
The speed controller for the eye roll) is
The output is the following formula, (α _m・ P_{m + 1}× V_{0 m} ²) / (Α _{m + 1}・ P_m・ V_{0m + 1}) (However, P_mIs the rated output of the roll drive motor, α_mIs low
Rate droop rate, V_{0 m}Is the rated speed of the roll,
m can be calculated by multiplying a constant given by (the order in which the transport rolls are counted from the upstream side).
It

[0010]

According to the above-mentioned means, the low
Between the rolls located on both sides of the
When controlling the tension of the scale object,
The directions of the forces that the rolls exert on the long object cancel each other out.
Thus, the motor speed control of the rolls on both sides is performed. This
In case of, the motor speed control is {(α _{m + 1}・ P_m×
V_{0m + 1} ²) / (Α _m・ P_{m + 1}・ V_{0 m})} Or {(α _m・
P_{m + 1}× V_{0 m} ²) / (Α _{m + 1}・ P_m・ V_{0m + 1})} Is satisfied
The value is multiplied by the output value of the tension control device, and based on the result of this multiplication.
The speed control device may be controlled accordingly. By this,
Interferes with the tension of long objects between rolls other than the target
To control the tension of a long object as expected without
You can

[0011]

Embodiments of the present invention will now be described with reference to the drawings.
While explaining. FIG. 1 shows the tension control of a strip-shaped long object of the present invention.
Block diagram showing the configuration of the tension control device that achieves the control method
Is. Note that the same components as those shown in FIG. 9 are the same.
Since we used quotes, duplicate explanations are given below.
Omit it. In this embodiment, as shown in FIG.
Add corresponding to each of the control devices 5a, 5b, 5c, 5d
Four containers 8a, 8b, 8c and 8d are provided. That
Between the tension control device 6b and the adder 8b.
Is connected between the tension control device 6c and the adder 8c.
The calculator 9b is connected. Furthermore, the tension control device 6a
And the adder 9a, the setting device 10a is connected between the
The setting device 10b is connected between the control device 6b and the adder 9b.
Setting device 10 between tension control device 6c and adder 8d.
c is connected. Setting devices 10a, 10b, 10c
Is for setting as shown in the following formula (however, in the formula
Α_i(I = 1 to n) is a value that each speed control device has.
Lower rate, P_i(I = 1 to n) is the constant of the drive motor of each roll
Rated output [kW], V_0i(I = 1 to n) is the rating of each roll
Speed [m / S]. Setting device 10a: (-α₂/ Α₁) ・ (P₁・ V ₀₂ ²) / (P
₂・ V ₀₁ ²) Setting device 10b: (-α₃/ Α₂) ・ (P₂・ V ₀₃ ²) / (P
₃・ V ₀₂ ²) Setting device 10c: (-α_Four/ Α₃) ・ (P₃・ V ₀₄ ²) / (P
_Four・ V ₀₃ ²) (Note that if there are n rolls, an n-1 setter is required.
In the (n-1) th setter, (-α_n/ Α_n-1)
・ (P_n-1・ V _0n ²) / (P_n・ V _0n-1 ²) Setting
It ) By performing such control, the control target
The long object on each roll between the entrance and the exit
The tensions are controlled so that the changes in the applied forces cancel each other out.
And give interference (disturbance) to rolls other than the control target
Is eliminated, and stable tension control can be performed.

Now, the calculation process of the above setting formula will be described. If the mechanical loss consumed by each roll is ignored, the steady solution of the tension between the rolls is calculated by the following equation (1). (However, T _i (i = 1 to n-1) is the tension between the rolls,
β _i (i = 1 to n) is 1 / α _i (i = 1 to n), K _i (i
= 1 to n) is a constant, and K is the acceleration of gravity is g.
_i = P _i × 10 ³ / (gV _0i ² ) (i = 1 to n), V is the speed of the long object being conveyed, and can be obtained from the following equation (2). It should be noted that T ₀ and T _n are tensions applied to the long object at the entrance side and the exit side of the transport section and are considered to be constant. ) (However, I _0i (i = 1 to n) is the rated current (A) of the drive motor of each roll, and I _i (i = 1 to n) is the load current (A) of the drive motor.) (1) When the tension T _i (i = 1 to n−1) between the rolls is obtained from the formula, the formula (3) of [Equation 1] is obtained. This (3)
Depending on the formula, the tension between certain rolls, for example T _m (m =
1- (n-1)) is independent of the tension between other rolls and independent, and is ΔT _m . This is expressed by equations (4) to (7) shown in [Equation 2].

FIG. 4 is a block diagram showing the configuration of a second tension control device for achieving the tension control method of the present invention. Figure 4
In FIG. 1, the same reference numerals are used for those having the same or the same functions as those in FIG. 1, and thus duplicated description thereof will be omitted. The tension control device of FIG. 4 is the same as that of FIG.
This corresponds to 0, and is the case where the downstream side transport roll is the operation end. In this configuration, the setter 10c is connected between the tension control device 6c and the adder 8c, the setter 10b is connected between the tension control device 6b and the adder 8b, and the setter 10a is added to the tension control device 6a. The setting values are sent from the output side to the input side of the setting devices 10a, 10b, and 10c connected between the devices 8a, which is the reverse of the configuration of FIG.

FIG. 5 is a block diagram showing the configuration of a third tension control device that achieves the tension control method of the present invention. Figure 5
Also, in the above, since the same reference numerals are used for the same or the same functions as those in the above-mentioned respective embodiments, the duplicated description will be omitted. This tension control device does not have a tension sensor,
As shown by comparison with the configuration shown in FIG. 1, which shows a configuration in which the tension is set manually or by a computer, the tension sensors 3a, 3b, 3c and the tension control devices 6a, 6 are shown in FIG.
b and 6c are removed, and instead of these, a tension setting device 11 is provided manually or by a calculator or the like. Manual setting device Since the composition is the same as that in FIG. 1, the description is omitted. In this embodiment, the tension is not automatically controlled because the closed loop control is not performed.

FIG. 6 is a block diagram showing the configuration of a fourth tension control device that achieves the tension control method of the present invention. In the tension control device shown in FIG. 6, a plurality of motors 4 are simultaneously driven by one speed control device, whereas each tension control device is assigned one speed control device to one drive motor. I am trying. Other configurations are the same as the configurations shown in FIG. 1, for example, and duplicate description will be omitted. Conveyor rolls have Q sets in one section and 4
It is divided into individual roll sections 13 _{-1 to} 13 _-4 . Then, one motor is connected to each of the Q sets of transport rolls in one section, and the motor is divided into four motor sections 14 _{-1 to} 14 _-4 in which the Q motors are one group. speed control device for each section _{5-1, 5-2}
5 Each _-4 are connected. In the example of FIG. 6, P
_{For i} (i = 1 to 4), the total sum of rated outputs of the plurality of roll drive motors in each section is used. Also, V
_{For 0i} (i = 1 to 4) and α _i (i = 1 to 4), the rated speed and the droop rate of the roll drive motor for each section are often the same. Therefore, for each section, A representative value may be adopted. According to such a configuration, the number of control devices 5 can be reduced as compared with the number of motors, which is advantageous in reducing equipment cost.

FIG. 7 is a block diagram showing the configuration of a fifth tension control device that achieves the tension control method of the present invention. Figure 7
In the above, each of the transport rolls is provided with a drive motor and a speed control device for controlling the speed of the drive motor. The Q-group of the transport rolls is made into one section, and is divided into four roll sections 13 _{-1 to} 13 _-4 . Then, one motor having a speed control device (5 _{-1 to} 5 _-4 ) for each motor is connected to each group of the Q sets of transport rolls of one section, and the Q number of motors are connected to one group. The motor is divided into four motor sections 14 _{-1 to} 14 _-4 . In the example of FIG. 7, the values of P _i , V _0i , and α _i may be the same as those of the example shown in FIG. With such a configuration, compared to the example of FIG. 6, the number of speed control devices 5 increases and the equipment cost increases, but on the other hand, the accuracy of tension control can be improved.

FIG. 8 is a characteristic diagram showing tension control characteristics when the present invention is applied to a continuous annealing furnace. Here, using the tension control device of FIG. 6, the roll section 13 _-1 is composed of three transport rolls, the roll section 13 _-2 is 14 transport rolls, the roll section 13 _-3 is 13 transport rolls, The roll section 13 _-4 is _composed of 11 transport rolls. As shown in FIG. 8, 950 kg → 10
When a command to change the tension to 30 kg (stepwise linear change) is given as ΔT ₂ , the control follows without delay and it is understood that there is no influence (interference) of other rolls. . In the above description, a steel plate is taken as an example of the elongated object 1, but the elongated object 1 is not limited to this, and may be any strip-shaped and elongated object such as paper, cloth, and film. The present invention can be applied. Also, not only the strip shape, but also the wire material (wire, cord, etc.),
The present invention can be applied to a slab such as a slab that is in a solidification process in a continuous casting facility. Further, in the above description, the force applied in the conveying direction of the long object is described as the tension (tensile force), but the tension has a negative value. That is, the present invention can be applied to the control of the compression force. Further, in the above-described embodiment, the control target is limited to the pinch roll, but the present invention is not limited to this and is similarly applicable to bridles, hearth rolls, helper rolls, and the like.

[0018]

[Equation 1]

[0019]

[Equation 2]

[0020]

[Equation 3]

[0021]

The present invention is constructed as described above.
Then, the following effects are achieved. Of the long object of claim 1.
In the tension control method, a long object is passed through multiple rolls.
And transport while controlling the tension between the rolls to a predetermined value.
In the tension control method for
Control the tension of the long object so that it does not interfere with the tension between other rolls.
When desired, each of the rolls located on both sides between the rolls
The directions of the forces exerted on the elongated object will cancel each other out.
Command given to the speed control device for the rolls on both sides
Since the modified value of is changed,
Without interfering with the tension of long objects between rolls,
The tension control of long objects can be controlled as expected
Become. In the tension control method for a long object according to claim 2,
Correction value of speed command given to the speed controller of the roll
The tension controller output to the upstream roll between specific rolls.
Speed of roll (m-th roll from the upstream side in the transport direction)
When using it as a correction value for the speed command given to the control device,
Flow side roll (m + 1th row from the upstream side in the transport direction)
The speed control device of
The expression, (α _{m + 1}・ P_m× V_{0m + 1} ²) / (Α _m・ P_{m + 1}・ V_{0 m}) Alternatively, the output of the tension control device can be fed downstream between specific rolls.
Side roll (m + 1th row from the upstream side in the transport direction)
Used as a correction value for the speed command given to the speed controller
If there is a roll on the upstream side,
The speed controller for the eye roll) is
The output is the following formula, (α _m・ P_{m + 1}× V_{0 m} ²) / (Α _{m + 1}・ P_m・ V_{0m + 1}) (However, P_mIs the rated output of the roll drive motor, α_mIs low
Rate droop rate, V_{0 m}Is the rated speed of the roll,
m is the value obtained by multiplying the constant given by the order of counting the transport rolls from the upstream)
As a result, the rolls other than the controlled object are interfered with.
The tension control of long objects as expected
You can

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a tension control device that achieves a tension control method for a long object of the present invention.

FIG. 2 is a block diagram showing a control block of speed control using the arithmetic expression of the present invention.

FIG. 3 is a block diagram showing another example of a control block for speed control using the arithmetic expression of the present invention.

FIG. 4 is a block diagram showing the configuration of a second tension control device that achieves the tension control method of the present invention.

FIG. 5 is a block diagram showing the configuration of a third tension control device that achieves the tension control method of the present invention.

FIG. 6 is a block diagram showing the configuration of a fourth tension control device that achieves the tension control method of the present invention.

FIG. 7 is a block diagram showing the configuration of a fifth tension control device that achieves the tension control method of the present invention.

FIG. 8 is a characteristic diagram showing an effect of control according to the present invention.

FIG. 9 is a block diagram showing a conventional tension control device.

FIG. 10 is a block diagram showing another example of a conventional tension control device.

FIG. 11 is a characteristic diagram showing control characteristics in a conventional tension control device.

[Explanation of symbols]

1 Long object 2a, 2b, 2c, 2d Conveying rolls 3a, 3b, 3c Tension sensor 4a, 4b, 4c, 4d Motor 5a, 5b, 5c, 5d Speed controller 5 _-1 , 5 _-2 , 5 _-3 , _5-4 Speed control device 6a, 6b, 6c Tension control device 7a, 7b, 7c Subtractor 8a, 8b, 8c, 8d Adder 9a, 9b Adder 10a, 10b, 10c Setting device 11 Tension setting device 12a, 12b, 12c Setting device 13 _{-1 to} 13 _-4 Roll section 14 _{-1 to} 14 _-4 Motor section

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location G05D 13/62 E 9132-3H 15/01 8610-3H

Claims (2)

[Claims] 1. A tension control method for transporting a long object through a plurality of rolls while controlling the tension between the rolls to a predetermined value. When you want to control the tension between rolls and non-interference,
The direction of the force exerted on the elongated object by each of the rolls located on both sides between the rolls, changing the correction value of the speed command given to the speed control device of the rolls on both sides to cancel each other, Control method for long object. 2. The speed given to the speed controller of the roll
The corrected value of the command determines the output of the tension controller between the specific rolls.
Roll on the upstream side of the
Used as a correction value for the speed command given to the speed controller
If there is a roll on the downstream side (m + from the upstream side in the transport direction)
The speed control device for the first roll) includes the tension control device.
The output of _{m + 1}・ P_m× V_{0m + 1} ²) / (Α _m・ P_{m + 1}・ V_{0 m}) Alternatively, the output of the tension control device can be fed downstream between specific rolls.
Side roll (m + 1th row from the upstream side in the transport direction)
Used as a correction value for the speed command given to the speed controller
If there is a roll on the upstream side,
The speed controller for the eye roll) is
The output is the following formula, (α _m・ P_{m + 1}× V_{0 m} ²) / (Α _{m + 1}・ P_m・ V_{0m + 1}) (However, P_mIs the rated output of the roll drive motor, α_mIs low
Rate droop rate, V_{0 m}Is the rated speed of the roll,
m is given in the order of counting the transport rolls from the upstream side)
Characteristic that the value multiplied by a constant is used as the correction value for the speed command
The tension control method for a long object according to claim 1.