JPH08109592A - Paper-making machine controller - Google Patents

Abstract

PURPOSE: To get rid of fluctuation in tension against the speed fluctuation of the rollers of the upper stream side. CONSTITUTION: In this paper-making machine controller in which rollers 2, 4 are arranged on both upperstream and downstream sides of calendering rollers 3 and the sheet material is conveyed while these rollers 2 to 4 are separately driven with electric motors 5, calendering roller speed correctors 10-14 are equipped to control the tension between the upper stream roller and the calendering roller to a constant value based on the real electric current of the electric motor for the calendering rollers, and a correction operation means 20 is provided to judge whether it is caused by the speed fluctuation of the upper stream roller or the calendering roller, and when it is caused by the upper stream roller, the speed of the downstream roller is corrected based on the speed correction signal from the speed ratio of the calendring roller to the downstream roller and the speed correction signal of the calendering roller, but when it is caused by the speed fluctuation of the calendering roller, the speed of the downstream roller is not corrected.

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 paper machine control device which conveys a sheet material and prevents a tension variation due to a speed change of a roll which performs a required processing treatment.

[0002]

2. Description of the Related Art Conventionally, a calendar section which is a part of a paper machine controller has a structure as shown in FIG. This calendar section portion is provided with a first roll 2 for conveying and processing a paper material 1 made from paper,
The calendar roll 3 and the second roll 4, a roll driving electric motor 5 for driving the respective rolls 2 to 4, a speed detecting means 6 for detecting the rotational speed of these electric motors 5, and a main speed reference value for the sheet material 1. , A draw speed setting means 8 for setting a speed difference (hereinafter referred to as a draw) with respect to the main speed reference value, a set speed output from these draw setting means 8 and a speed detecting means 6 And a motor control means 9 for outputting a signal for controlling the motor 5 on the basis of the detected speed.

Further, the calendar section portion has a current detection means 10 for detecting the current of the calendar roll driving electric motor 5 for driving the calendar roll 3, and a current display means 11 for displaying the current detected by the current detection means 10. And a current control means 13 for calculating a speed correction value from the current value detected by the current detection means 10 and the current reference value set by the current reference setting means 12,
There is provided a control switching means 14 for turning on and off a speed correction value which is an output signal of the current control means 13, and the speed correction calculation value corrects the set speed of the draw setting means 8 on the calendar roll 3 side. There is.

The reason why the draw setting means 8 and the current control means 13 are provided in the calendar section of the paper machine controller as described above will be explained. The paper-made sheet material 1 is transported while being dehydrated and dried until it reaches the calendar roll 3. Here, the calendar roll 3 smoothes the surface of the sheet material while pressing the sheet material 1 and conveys the sheet material 1 to the second roll 4 side. This second
The sheet material 1 that has passed through the roll 4 is wound up as a product by a winding roll (not shown).

As described above, the sheet material 1 is dried and contracts as it goes to the rear stage side. Therefore, the sheets 1 are provided with a speed difference between the rolls 2 to 4 corresponding to the respective sections.
An adjusting means is required to absorb the contraction of the. Therefore, the draw setting means 8 for setting the draw is provided for each of the rolls 2 to 4, and the draw is adjusted with respect to the speed reference set by the main speed reference setting means 7. This adjustment work is performed by the operator while observing the tension of the sheet material 1.

However, after the line is stabilized, controlling the tension of the sheet material 1 to a constant value makes it possible to make paper of a more uniform quality than to keep the speed constant, so that the motor 5 for driving the calendar roll 3 is made. A current control means 13 is added to the outer loop of the electric motor control means 9 for controlling the above in order to keep the tension constant.

Next, the operation of the calendar section of the paper machine controller will be briefly described. First, the operator performs a sheet passing operation in which the sheet material 1 is sequentially passed through the rolls 2 to 4 of each section. At this time, calendar roll 3
Opens the control switching means 14 and draw setting means 8
Speed control (draw control) is performed based on the output signal of.
When the sheet material 1 reaches the calendar roll 3 and is wound around the winding roll (not shown) via the second roll 4, the operator adjusts the draw setting means 8 to adjust the tension of the sheet material 1. To do.

When the product stabilizes in this state, the operator reads the actual current of the calendar roll drive motor 5 from the current display means 11 and adjusts the current reference setting means 13 to the actual current. Next, the control switching means 14 is set to the closed state, and the current control means 13 is utilized. This current control means 13
Outputs the speed correction signal by arithmetically amplifying the deviation between the current reference signal output from the current reference setting means 12 and the actual current signal detected by the current detection means 10. Then, this speed correction signal is applied to the draw setting means 8 on the calendar roll 3 side.
The current of the electric motor 5 for driving the calendar roll 3 is controlled to be constant by adding it to the output of.

In the case of a DC motor, since the motor current and the output torque are in a proportional relationship, if the value obtained by converting the detected actual current into the output torque is τM, then τM = τa + τl + τT (1) . Here, τa is a torque required to accelerate or decelerate the roll, τl is a mechanical loss torque, and τT is a tension torque. Further, τl is generally a function of speed, and assuming that the tension of the paper is T and the roll radius of the calendar roll 3 is R, the tension component torque τT is expressed by τT = T · R (2). Furthermore, when the speed is constant, the acceleration / deceleration torque τ
a becomes 0. Therefore, when the speed is constant, it can be seen from equation (1) that the tension becomes constant if the current is controlled to be constant.

[0010]

Therefore, the driving operation of the calendar section portion as described above is performed by the first roll 2
When the speed of the first roll 2 changes for some reason, the tension between the first roll 2 and the calendar roll 3 becomes constant when the speed of the first roll 2 is constant.
However, the tension between the calendar roll 3 and the second roll 4 fluctuates.

For example, the first roll 2 and the calendar roll 3
And the tension between the calender roll 3 and the second roll 4 is T2.
It is assumed that the speed of the roll 2 of No. 2 has changed so as to decrease. At this time, the tensions T1 and T2 between the rolls are approximately expressed by equations (3) and (4).

T1 = A · E · {(v _c −v ₁ ) / v ₁ } (3) T2 = A · E · {(v ₂ −v _c ) / v _c } (4) above In the formula, A is the cross-sectional area of the paper, E is the Young's modulus, v ₁ is the speed of the first roll 2, v _c is the speed of the calendar roll 3, and
v ₂ is the speed of the second roll 4.

Therefore, as is apparent from the equation (3), when the speed of the first roll 2 changes, the tension T1 also changes, but since the calendar roll 3 controls the current, T1 is kept constant. The speed of the calendar roll 3 decreases as described above. However, since the speed of the second roll 4 does not change, the tension between the calendar roll 3 and the second roll 4 increases from the above formula (4), and in the worst case, the sheet material 1 breaks, There are problems such as line interruptions and breakdowns, which reduce production efficiency and product quality.

The present invention has been made in view of the above circumstances, and provides a paper machine controller for eliminating the fluctuation of the tension due to the change of the speed of the roll and keeping the tension constant at all times so as to produce the paper of uniform quality. The purpose is to provide.

[0015]

In order to solve the above-mentioned problems, the invention corresponding to claim 1 is such that rolls are arranged on the upstream side and the downstream side of a calendar roll, respectively, and these rolls are individually arranged. In a paper machine control device that conveys a sheet material while being driven by an electric motor, when the speed of the upstream roll changes in comparison with a reference value, the downstream side using a speed ratio between a calendar roll and the downstream roll. The paper machine control device is provided with a correction calculation means for correcting the roll speed.

Next, the invention according to claim 2 is a papermaking machine in which rolls are arranged on the upstream side and the downstream side of the calender rolls, respectively, and the rolls are individually driven by an electric motor to convey the sheet material. In the machine controller,
A calendar that corrects the speed of the calendar roll by extracting a speed correction signal of the calender roll such that the tension between the upstream roll and the calender roll is controlled to be constant based on the current flowing in the electric motor that drives the calender roll. Roll speed correction means, to determine which speed change of the upstream roll and the calendar roll, when the speed change of the upstream roll, the speed ratio between the calendar roll and the downstream roll, the calendar roll Using the speed correction signal of, to correct the downstream roll speed by obtaining the speed correction signal of the downstream roll, also without obtaining the speed correction signal of the downstream roll when the speed change of only the calendar roll Papermaking machine provided with correction calculation means for correcting only the speed on the calendar roll side by the calendar roll speed correction means A control device.

As an example of the configuration of the correction calculation means, a speed reference value storage means for taking in each roll speed during constant tension control and storing it as a reference value, and a reference value for the upstream roll and the calendar roll are provided. Whether the speed of the upstream roll or the calendar roll is determined by comparing with the detected speed of each roll, and whether the speed of the downstream roll is corrected,
Correction roll determination means for determining correction of only the calendar roll, and speed ratio calculation means for determining the speed ratio between the calendar roll and the downstream roll when correcting the downstream roll according to the result of this determination, and Downstream roll speed correction amount calculation means for multiplying the speed ratio obtained by the speed ratio calculation means by the speed correction signal of the calendar roll to obtain a speed correction amount to be added to the downstream roll.

[0018]

Therefore, in the invention corresponding to claim 1, when the speed of the upstream roll changes compared with the reference value, the constant tension control is performed on the calender roll side by taking the above means. The speed on the calendar roll side can be changed according to the speed change of the upstream roll when performing, but as long as the speed of the downstream roll is rotating at the set speed, the calendar roll and the downstream roll The tension of the sheet material between them changes. Therefore, in the correction calculation means, at least the speed ratio between the calendar roll and the downstream roll is obtained, and if the correction speed corresponding to the speed ratio is corrected to the set speed of the downstream roll, the correction roll will be between the calender roll and the downstream roll. The tension of the sheet material can be kept constant.

Next, in the invention according to claim 2, the calendar roll speed correcting means is provided on the calender roll side, and the calender roll is normally operated on the basis of the current flowing in the motor for driving the calender roll and the current reference value. The speed on the calendar roll side is corrected by obtaining a speed correction signal for the calender roll that controls the tension between the calender rolls to a constant value.

In this state, the correction calculation means detects the speeds of the upstream roll and the calendar roll, determines which speed of these rolls changes, and when it determines that the upstream roll has changed speed, it determines that Speed ratio with the downstream roll, using the speed correction signal of the calendar roll, the speed correction signal of the downstream roll is obtained to correct the downstream roll speed, while the speed change of the calendar roll was determined. At this time, by appropriately correcting the speed of the calendar roll according to the speed correction signal of the calendar roll obtained by the calendar roll speed correction means without obtaining the speed correction signal of the downstream side roll, it is possible to appropriately determine which roll has the speed change. Thus, the required roll speed correction can be performed quickly, and thus tension fluctuation can be reliably prevented.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a paper machine controller according to the present invention. This controller is the first
The configuration is almost the same as that of FIG. 2 except for the speed correction function of the second roll 4 due to the speed change of the roll 2, and therefore, the same parts as those in FIG.

That is, the calender section portion of the papermaking machine control unit comprises a first roll 2, a calender roll 3 and a second roll 4 for conveying and processing the sheet material 1 made from paper, and each roll 2 To 4 for driving the rolls, speed detecting means 6 for detecting the rotational speeds of these motors 5, main speed reference setting means 7 for setting the main speed reference value of the sheet material 1, and this main speed reference Draw setting means 8 for setting the speed difference with respect to the value, that is, the draw
And a motor control means 9 for outputting a signal for controlling the electric motor 5 based on the set speed output from the draw setting means 8 and the detected speed of the speed detecting means 6, as well as a calendar roll for driving the calendar roll 3. Current detection means 10 for detecting the current of the drive motor 5 and current display means 1 for displaying the current detected by the current detection means 10.
1, a current control means 13 for calculating a speed correction value from a current value detected by the current detection means 10 and a current reference value set by the current reference setting means 12, and an output signal of the current control means 13. A control switching means 14 for turning on and off the speed correction value is provided, and the speed correction value is configured to correct the set speed of the draw setting means 8 on the calendar roll 3 side.

Further, in the present control device, it is detected which of the first roll 2 and the calendar roll 3 the speed is changing, and when the speed of the first roll 2 is changing, the speed on the second roll 4 side is detected. A correction calculation means 20 for correcting the is provided. The correction calculation means 20 includes a speed reference value storage means 21 that takes in the speeds of the rolls 2 to 4 during constant tension control and stores them as reference values, and these reference values and each roll 2 to 2.
Whether the first roll 2 or the calender roll 3 changes in tension due to a change in the tension is compared with the detected speed of No. 4, and the second roll 4 side is corrected according to the result of the judgment. , Or the correction roll determination means 22 for determining whether to correct only the calendar roll 3 and the speeds of the calendar roll 3 and the second roll 4 when performing correction on the second roll 4 side in accordance with the result of this determination. A speed ratio calculating unit 23 for obtaining a ratio, and a second roll speed correction for obtaining a speed correction amount to be added to the second roll 4 by multiplying the speed ratio obtained by the speed ratio calculating unit 23 by the speed correction amount of the calendar roll 3. The minute calculation means 24 is provided.

Next, the operation of the above apparatus will be described. After the paper passing operation is performed as in the conventional apparatus, the actual current of the electric motor 5 is read from the current display means 11 during the constant tension control, and the current reference of the current reference setting means 12 is set so as to match the actual current. Further, the control switching means 14
Is set to the closed state, and the current control for the calendar roll 3 is executed. At this time, the speed reference value storage means 21 of the correction calculation means 20 takes in the speeds of the first roll 2, the calendar roll 3 and the second roll 4 from each speed detection means 6 and stores them as reference values. After that, it is assumed that the correction calculation means 20 constantly monitors the actual speeds of the rolls 2 to 4.

When the speed of the first roll 2 changes in this state, the current control means 13 generates a speed correction signal for the calendar roll 3 so that the tension is kept constant by the current control. Changes. At this time, the speed correction signal is also input to the correction calculation means 20. Here, when the correction roll determination means 22 of the correction calculation means 20 determines that the speed of the first roll 2 has changed, the following calculation processing is performed by the speed ratio calculation means 23 and the second roll speed correction amount calculation means 24. The reason for performing the calculation will be described.

When the speed of the first roll 2 changes, the calendar roll 3 is controlled so that the tension becomes constant by controlling the current.
Change the speed of. At this time, if the speed of the calendar roll 3 changes by λ, the tension T'2 between the calendar roll 3 and the second roll 4 becomes as shown in formula (5) from formula (4).

T′2 = A · E · {(v ₂ −v _c + λ) / (v _c + λ)} (5) From these equations (4) and (5), T2 and T′2 are When the speed of the second roll 4 v _'2 to to equalize, is as follows (6).

T2 = AE {(v ′ ₂ −v ′ _c + λ) / (v ′ _c + λ)} (6) When this equation is modified, the following equation is obtained. v ′ ₂ = v ₂ + (v ₂ / v _c ) λ (7) Therefore, as is apparent from the equation (7), the speed of the first roll 2 changes so that the tension becomes constant. when changing the speed v _c of the calender roll 3, the speed ratio of the speed v ₂ of the speed v _c and the second roll 3 of the calender rolls 3 (v
₂ / v _c ) is multiplied by the speed correction signal λ of the calendar roll 3 and added to the output of the draw setting means 8 on the second roll 4 side as a correction amount to be added to the second roll 4, The tension with the second roll 4 becomes constant.

However, when the speed correction signal of the calendar roll 3 which is the output signal of the current control means 13 is generated despite the fact that the first roll 2 has not changed, the second roll 4 If the speed is corrected, a problem such as breakage of the sheet material 1 occurs. Therefore, the correction roll determination means 2
In No. 2, when it is judged that the speed of the first roll 2 has not changed, the tension is controlled to be constant by adding the speed correction signal which is the output signal of the current control means 13 to only the calendar roll 3.

More specifically, when the speed correction signal of the calendar roll 3 which is the output of the current control means 13 is corrected to the speed increasing side due to the speed change of the first roll 2, the second roll By adding the speed correction signal obtained by the equation (7) to 4, the speed of the second roll 4 can be increased at the same rate.

However, if the cause of increasing the speed of the calendar roll 3 is the decrease of the speed of the calendar roll 3, the draw between the calendar roll 3 and the second roll 4 must have changed. If the output of the current control means 13 is simply added to the second roll 4, the speed difference becomes wider and the tension increases, which causes breakage of the sheet material 1.

Therefore, as described above, the correction calculation means 20
Then, the reference value stored in advance by the speed reference value storage means 21 and the current speed of the first roll 2 are constantly monitored, and only when a speed difference occurs, the calendar which is the output signal of the current control means 13 is displayed. Using the speed correction signal of the roll 3 and the reference values of the rolls 2 to 4 stored in advance, the speed correction value of the second roll 4 is calculated by the formula (7),
The correction is performed in addition to the output of the draw setting means 8 on the second roll 4 side, and in other cases, the correction is not performed on the second roll 4 side.

Therefore, according to the configuration of the above-described embodiment, when the speed of the first roll 2 changes in comparison with the speed of the first roll 2 and the reference value stored in charity, the calendar is changed. On the roll side, the speed on the calendar roll side can be changed according to the speed change of the second roll 2 only when the constant tension control is performed, but the speed of the second roll 4 does not change at all. do not do. Then, the first roll 2
When it is determined that the speed of the calendar roll 3 has changed, the tension of the sheet material 1 between the calendar roll 3 and the second roll 4 changes, so the correction calculation means 20 causes the calendar roll 3 and the second roll 4 to move.
Of the sheet material 1 between the calender roll 3 and the second roll 4 because the speed ratio with the roll 4 of the second roll 4 is calculated and the correction speed is calculated using the speed ratio to correct to the set speed of the second roll 4. The tension of can be kept constant.

Further, the correction calculation means 20 detects the speeds of the first roll 2 and the calendar roll 3 and judges which of the speeds of the rolls 2 and 3 changes, and determines whether the speed of the first roll 2 has changed. When determined, the speed ratio between the calendar roll 3 and the second roll 4 and the speed correction signal of the calendar roll 3 are used to obtain the speed correction signal of the second roll 4 to determine the speed of the second roll 4. Corrected, while calendar roll 3
If the speed change signal of the second roll 4 is determined, the speed of the calendar roll 3 is corrected according to the speed correction signal of the calendar roll 3 calculated by the calendar roll speed correction calculation means 24 without calculating the speed correction signal of the second roll 4. It is possible to appropriately determine whether or not the roll speed has changed and quickly perform the required roll speed correction, and thus it is possible to reliably prevent tension fluctuations.The present invention is variously modified without departing from the scope of the invention. Can be implemented.

[0035]

As described above, according to the present invention, it is possible to determine which roll has a change in speed and correct the required roll-side speed according to the change in speed of the roll.
It is possible to eliminate tension fluctuations quickly and surely, perform constant processing while always maintaining a constant tension, and produce paper of uniform quality.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a paper machine controller according to the present invention.

FIG. 2 is a diagram showing a configuration example of a correction calculation unit shown in FIG.

FIG. 3 is a diagram showing a configuration of a conventional paper machine control device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Sheet material, 2 ... 1st roll, 3 ... Calendar roll, 4 ... 2nd roll, 5 ... Electric motor, 6 ... Speed detection means, 7 ... Main speed reference setting means, 8 ... Draw setting means, 9
... motor control means, 10 ... current detection means, 13 ... current control means, 20 ... correction calculation means, 21 ... speed reference value storage means, 22 ... correction roll determination means, 23 ... speed ratio calculation means, 24 ... second roll Speed correction amount calculation means.

Claims (3)

[Claims] 1. A paper machine control device in which rolls are arranged on the upstream side and the downstream side of a calender roll, respectively, and the rolls are individually driven by an electric motor to convey a sheet material. When the speed changes in comparison with the reference value, the paper machine controller is provided with correction calculation means for correcting the speed of the downstream roll by using the speed ratio between the calendar roll and the downstream roll. . 2. A paper machine control device in which rolls are arranged on the upstream side and the downstream side of a calender roll, respectively, and the rolls are individually driven by an electric motor to convey a sheet material. And a calendar roll speed correcting means for correcting the speed of the calendar roll such that the tension between the upstream roll and the calender roll is controlled to be constant based on the current flowing in the electric motor, and the calender roll speed is corrected. , The speed change of the upstream roll and the calendar roll, the speed ratio between the calendar roll and the downstream roll when the speed change of the upstream roll, the speed correction signal of the calendar roll Using the downstream roll speed correction signal to correct the downstream roll speed, When the speed of only the roll changes, the correction calculation means for correcting only the speed of the calendar roll side by the calendar roll speed correction means without obtaining the speed correction signal of the downstream side roll is provided. Machine control device. 3. The correction calculation means includes a speed reference value storage means for taking in each roll speed during constant tension control and storing it as a reference value, a reference value for the upstream roll and the calendar roll, and a detected speed for each roll. Compensation roll determination means for determining whether the speed change of the upstream roll or the calendar roll by comparing with, and performing the speed correction of the downstream roll, or the correction of only the calendar roll, and this determination result When the correction of the downstream side roll is performed according to the above, the speed ratio calculation means for obtaining the speed ratio between the calendar roll and the downstream side roll, and the speed ratio obtained by this speed ratio calculation means are multiplied by the speed correction signal of the calendar roll. 3. The paper machine control device according to claim 1, further comprising: downstream roll speed correction amount calculation means for obtaining a speed correction amount to be applied to the downstream roll. .