JPH09183544A - Mechanical loss compensating method in sheet takeup control - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanical loss compensating method in takeup control of a sheet, with which it is possible to compensate the mechanical loss not only resulting from variation of the revolving speed of a coil but from a change in the coil weight or takeup angle. SOLUTION: The amperage for the set tension of a drive motor to take up a sheet 1 is compensated in its portion corresponding to the friction loss current proportional to the revolving speed of a bearing, and the bearing load F as the resultant of the set tension T and the coil weight W(t) in compliance with the takeup coil diameter D of the sheet 1 is calculated from the sheet intrude angle θ(t) to the coil, and on the basis of the bearing load F, the torque loss is determined and compensation is made by adding even the loss current corresponding to it to the tension current set value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a mechanical loss compensating method in tension control of a drive motor that winds sheets such as metal strips and paper with a constant tension.

[0002]

2. Description of the Related Art A DC motor used as a drive motor of this type generally employs one of the following control methods in order to keep the tension T constant. The armature current I is kept constant and the field flux φ is increased in proportion to the increase of the coil diameter D.

The armature current I is made proportional to D / φ. However, in reality, the influence of energy loss due to mechanical loss such as friction of the winding device is unavoidable. That is, since the coil diameter increases and the weight increases as the sheet is wound on the reel, torque loss due to friction of the bearing increases substantially in proportion to the rotation speed of the reel. A tension control that uses a so-called mechanical loss compensation control for compensating the current of the winding motor to compensate for this loss is widely known, and is disclosed in, for example, Japanese Patent Laid-Open No. 54-55268. This is a method in which the field is automatically weakened by the armature voltage, and the armature current command is a value obtained by multiplying the tension command (setting and compensation added) by the winding diameter and dividing by the field flux. .

On the other hand, in Japanese Patent Laid-Open No. 59-225816, the method of increasing the field flux φ along with the increase of the coil diameter D due to the progress of winding actually causes a frictional resistance of the mechanical system. In consideration of the fact that the tension is not constant, the actual tension applied to the wound metal plate is detected, the signal related to the detected actual tension is converted into a control signal related to the motor current value, and the signal and the control related to the set tension are controlled. A method for controlling the actual tension of a winding device is disclosed in which the actual tension is made equal to the set tension based on the signal.

Further, Japanese Patent Publication No. 3-69820 discloses that
When the coil is not attached to the winder, the coil with the maximum diameter is attached, and the coil with the intermediate diameter is attached, the value of the mechanical loss current with respect to the rotation speed of the DC motor is measured, and the rotation speed is set using the coil diameter as a parameter. And a mechanical loss current, the coil diameter is calculated by detecting the rotation speed of the DC motor and the speed of the rolled material during winding, and this coil diameter and the detected rotation speed of the DC motor. The mechanical loss current is calculated by applying to the above relationship, and the calculated value of the mechanical loss current is added to the value of the current flowing through the DC motor calculated according to the constant current control, field weakening control, and acceleration / deceleration compensation system. A tension control method for a winding machine is disclosed in which mechanical loss current compensation is performed by adding the two.

[0006]

In the conventional friction loss compensation method proportional to the number of rotations of the reel, the load on the reel bearing changes in proportion to the increase or decrease in the weight of the coil to be paid out or wound during the line operation. As a result, the friction loss of the bearing fluctuates and the tension changes. If the payout or the winding is not performed with a constant tension, there arises a problem that, for example, the metal strip has defects such as scratches, winding slack, and winding tightening. Also, the magnitude of the operating tension,
The force generated in relation to the payout or winding angle of the metal strip also causes a fluctuation in the friction loss of the bearing and induces a tension fluctuation.

On the other hand, in the case of the actual tension control in which the actual tension is detected and made equal to the set tension as in Japanese Patent Laid-Open No. 59-225816 and Japanese Patent Publication No. 3-69820, troubles due to tension fluctuation occur. Although it does not exist, it is expensive to install an actual tension measuring device consisting of multiple rolls and pressure detectors. Further, it takes time and effort to actually measure the values of the mechanical loss current with respect to the rotational speed of the electric motor for various coil diameters and to previously obtain the relationship between the rotational speed and the mechanical loss current with the coil diameter as a parameter.

The present invention compensates not only for the change in the coil rotation speed but also for the mechanical loss caused by the change in the coil weight and the change in the winding angle, and when the actual tension control using the tensiometer is not performed. It is an object of the present invention to provide a mechanical loss compensation method in sheet winding control that is particularly effective for the above.

[0009]

SUMMARY OF THE INVENTION The present invention is a machine for sheet winding control in which a preset tension current value of a drive motor for winding a sheet is compensated for a friction loss current proportional to the rotational speed of a bearing. In the loss compensation method, the bearing load applied to the bearing, which is the resultant force of the coil weight and the set tension according to the winding coil diameter of the sheet, is calculated using the sheet entrance angle to the coil,
A torque loss is obtained based on the bearing load, and a current value corresponding to the torque loss is further added to a tension current setting value that compensates for a friction loss current amount proportional to the rotation speed of the bearing of the drive motor. And

According to the present invention, the present value of the coil diameter of the sheet wound on the reel is detected and calculated to calculate the present value of the coil weight, and the present value of the coil weight and the operating tension of the reel are dynamically combined. And calculate the load on the reel bearing,
Furthermore, after calculating the bearing friction loss amount of the reel, the torque loss amount is added as a mechanical loss compensation amount of the reel drive motor to the current command in addition to the friction loss compensation by the rotation speed of the reel bearing. Not only the bearing friction loss proportional to the reel rotation speed, but also the friction loss of the reel bearing due to the coil weight and the operating tension can be compensated, and the sheet can be wound up or paid out more strictly than ever with a constant tension.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of winding control of a strip sheet which is an embodiment of the present invention. A strip 1 which is a sheet is wound around a payoff reel 2 in a coil shape. The coil 3a is unwound by the drive of the pay-out drive motor 6a and continuously fed through the coil 3a to the processing device 5 for predetermined processing. The strip 1 that has been processed is continuously wound as a coil 3b on a tension reel 4 that is rotated by the drive of a winding drive motor 6b. At this time, for example, on the pay-off reel 2 and the tension reel 4, the outer diameter D of the coils 3a and 3b continuously changes, but the strip 1 is wound with a constant tension regardless of the change of the outer diameter D. The payout drive motor 6a and the winding drive motor 6b are controlled.

Taking the case of the tension reel 4 as an example,
Then, first, the winding is performed with a constant set tension T [kg].
In order to take it, the set tension T is tensioned by the current converter 8.
Force setting current I_TConvert to. And this tension setting current I
_TIs supplied to the winding drive motor 6b through the power supply device 9.
The actual detected current value I of the winding drive motor 6b _O
Is fed back to the automatic current controller (ACR) 10
And winding up to supply a constant current.
The dynamic motor 6b is controlled. Then actually
Is the friction of the bearing generated while the tension reel 4 is rotating.
The loss causes an increase in the load of the winding drive motor 6b.
Therefore, as described above, the tension setting current I_TControlled to be constant
It is not possible to keep the winding tension constant just by
Yes. Therefore, the effect of friction loss proportional to the rotation speed of the bearing
The winding tension becomes weaker as a result, and the tension reel 4
Problems such as winding slack occur. Therefore, the winding drive
Rotation speed N of the motor 6b₁Pulse generator (PLG)
11, the bearing friction loss from the calculator 12
Mechanical loss compensation current value I_L2To get the tension
Set current I_TCurrent added to (I_T+ I_L2) Command current
To ACR10. As a result,
Compensate for the friction loss as shown, and keep the tension constant to some extent.
Control becomes possible. Up to this point, it has been performed conventionally.

However, it cannot be said that the winding with a constant tension is insufficient only by compensating for the friction loss of the bearing according to such a rotation speed. This is because the coil diameter increases as the winding of the strip 1 onto the tension reel 4 increases, and the load applied to the bearing of the tension reel 4 increases, so the mechanical loss amount of the bearing resulting from this also increases. Eventually, an increase in the load of the winding drive motor 6b is induced, and as a result, problems such as winding slack in the tension reel 4 are promoted. FIG. 2 is a graph showing the relationship between the current coil diameter and the mechanical loss amount, and the mechanical loss amount also increases as the current coil diameter D increases. In particular, in the case of a winding device that does not perform actual tension control, insufficient tension occurs remarkably due to this increase in coil weight.

On the other hand, according to the present invention, the current value commensurate with the increase in the bearing load based on the coil weight, which increases in proportion to the increase in the diameter D of the coil 3b, is used as the mechanical loss compensation current. Calculated by the arithmetic unit 20, and using this as the second mechanical loss compensation value, the added current ( _IT +
I _L2 ) is further controlled using the command current.

That is, the outline of the mechanical loss compensating method in the sheet winding control of the present invention is to calculate the current coil weight W _(t) according to the current coil diameter D. Find the sheet entry angle θ _(t) into the current coil. Set winding tension T and current coil weight W _(t) using θ _{( t)}
The synthetic force F of and is calculated.

Torque loss due to bearing friction τ _L from the above-mentioned combined force F which is a bearing load, bearing friction coefficient μ, and coil diameter D
_{Is calculated} and converted into a current value I _L1 to obtain the current value I _L1.
Is added to the tension setting current I _T of the winding drive motor 6b. Thus, in addition to the compensation of the friction loss proportional to the rotation speed of the bearing, the compensation of the mechanical loss due to the increase of the bearing load is also performed.

Specifically, the rotational speed N ₁ (rotational speed of the tension reel 4) of the winding drive motor 6b is set to PLG1.
1 and the speed detection roll 2 of the strip 1
The rotation speed N ₂ of No. 1 is detected by the PLG 22, both detection values N ₁ and N ₂ are input to the coil diameter calculation device 23, and the coil 3 is detected.
The current coil diameter D of b is calculated. If the outer diameter of the tension reel 4 is D ₀ , it can be calculated from D = (N ₂ / N ₁ ) × D ₀ .

From the obtained current coil diameter D, the specific gravity ρ of the strip 1 and the strip width l, the current coil weight W _(t)
= (Πρl / 4) × (D ² −D ₀ ² ) is calculated. On the other hand, the sheet entry angle θ _(t) is calculated as follows. Now
The distance d ₀ between the feed surface of the strip 1 and the axis of the tension reel 4 of the line, the feed surface of the strip 1 and the coil 3b
The distance d ₁ between the outer diameters of the _two is the distance d ₂ between the axial center of the guide roll 24 at the entry start position of the strip 1 and the winding start position around the coil 3 b, and the radius of the current coil diameter D is D / 2.
Therefore, from the figure, the seat entry angle θ _(t) = tan ^-1 (d
₀ −D / 2) = tan ⁻¹ (d ₁ / d ₂ ).

From the obtained current coil weight W _(t) , the sheet advancing angle θ _(t) and the set tension T, as shown in FIG.
The following formula for calculating the combined load F as the bearing load is obtained. _{F = {(Tcosθ (t)} ) 2 + (W (t) -Tsinθ (t)) 2} 1/2 = (T 2 + W (t) 2 -2W (t) Tsinθ (t)) 1/2 This The torque loss τ _L due to the bearing friction is obtained as follows from the value of the bearing load F obtained by the above synthesis, the bearing friction coefficient μ, and the coil diameter D.

Τ _L = F / 2 × μ × D / 2 This torque loss τ _L is converted into a mechanical loss compensation current I _L1 by the current converter 25 and added to the tension setting current I _T. Thus, the total current I _REF obtained by adding the mechanical value compensation current I _L2 proportional to the bearing rotation speed to the current value I _T + I _{L1 obtained} by adding the mechanical loss compensation current I _L1 due to the bearing load to the tension setting current I _T. The current is sent to the ACR 10 as a command current for the winding drive motor 6b. As a result, the friction loss proportional to the rotation speed of the bearing is compensated, and also the friction loss due to the bearing load is compensated, so that the rotation speed and the weight change of the coil 3b wound around the tension reel 4b are not affected. It is possible to take up extremely stable winding with constant tension.

According to the sheet winding control method of the present invention, in the reel in which the actual tension control is not performed by using the tensiometer,
Especially effective. In the above embodiment, the case of controlling the winding of the strip on the tension reel has been described, but the present invention is not limited to this, and even in the case of a pay-off reel, the payout of paper, etc., It is also applicable in the case of winding.

[0022]

As described above, according to the present invention,
Not only does the tension current value of the drive motor that winds the sheet compensate for the friction loss current that is proportional to the rotation speed of the bearing, but also the sheet entrance coil angle θ _(t) is used to determine the sheet winding coil diameter. Coil weight according to D W _(t)
Since the bearing load F, which is the resultant force between the load and the set tension T, is calculated and the current component corresponding to the torque loss due to the bearing load is also compensated, not only the change in the coil rotation speed but also the change in the coil weight is affected. By compensating for this, it is possible to always wind up and pay out the sheet with a constant tension, and it is possible to completely prevent the occurrence of defects such as scratches, looseness, and tightening at the time of winding and rewinding the sheet product. Play.

[Brief description of the drawings]

FIG. 1 is a block diagram of an example of an embodiment of winding control according to the present invention.

FIG. 2 is a graph showing a relationship between a change in coil diameter and a mechanical loss amount.

FIG. 3 is a diagram illustrating a method of synthesizing a bearing load from a coil weight and a sheet tension in the method of the present invention.

[Explanation of symbols]

 1 sheet (strip) 3a coil 4 tension reel 6a winding drive motor

Claims (1)

[Claims] 1. A mechanical loss compensating method in sheet winding control, wherein a preset tension current value of a drive motor for winding a sheet is compensated for a friction loss current proportional to a rotation speed of a bearing. The bearing load applied to the bearing, which is the total force of the coil weight and the set tension corresponding to the winding coil diameter of the sheet, is calculated using the sheet advancing angle, and the torque loss is calculated based on the bearing load, and the torque is calculated. A mechanical loss compensating method in sheet winding control, further comprising adding a current value corresponding to a loss to a tension current setting value that compensates for a friction loss current amount proportional to the rotational speed of the bearing of the drive motor.