JPH0655560A - Method and apparatus for controlling thickness of sheet in calender - Google Patents

Abstract

PURPOSE:To make the thickness of a product constant even when the amount of a bank or the like, that is, the state at the entering side is changed, by offsetting the amount of the deformation obtained from a spring constant when a supporting system between upstream rolls is deformed and the roll load subsequent to the change of tire state at the entering side, thereby controlling the roll gap to be constant. CONSTITUTION:A load cell 16 is provided to detect tone roll load between a first and a second rolls 11 and 12 in a calender. At the same time, a hydraulic cylinder 18 is set in an axle box of the first, roll 11 to adjust the roll gap. A controller 26 controls the load cell 16 and the hydraulic cylinder 18. A spring constant when a supporting system between tone rolls 11 and 12 at the upstream side of the calender is deformed in the inter-axial direction of the rolls is obtained beforehand. Then, the roll load when the state of the upstream rolls 11, 12 is changed at the entering side is detected. The amount of the deformation of the supporting system is obtained from the roll load and the spring constant, and the calender is controlled to offset the amount, of the deformation to make the roll gap constant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for controlling the thickness of a product to be constant by a calender, and knowing the fluctuation of the sheet thickness by detecting the fluctuation of the rolling reaction force, and controlling the roll gap to control the sheet. The thickness is made constant.

[0002]

2. Description of the Related Art Even in a calendar in which rubber or plastic is rolled into a film, there is a demand for improvement in accuracy with respect to product thickness.

Therefore, in the conventional calendar,
The operation control is performed according to the bank accumulated between the rolls. For example, in the method disclosed in Japanese Patent Laid-Open No. 52-132072, as shown in FIG. The bank 4 formed in the gap 3 is scanned by the camera 6 while being illuminated by the luminaire 5 to calculate the bank amount, and based on the calculated value, the supply amount of the strip-shaped resin material 8 conveyed by the conveyor 7 Are trying to control.

That is, by making the amount of banks supplied between the rolls 1 and 2 constant, it is attempted to prevent product defects such as thickness variation due to changes in the amount of banks.

[0005]

SUMMARY OF THE INVENTION Such a roll 1,
Since the amount of the bank supplied between the two is determined based on the planar image information, the amount of the bank cannot be accurately obtained, and the amount of the bank cannot be appropriately controlled. There is a problem in that the accuracy cannot be improved.

In the calendar, the rolls 1,
Even if the bank amount supplied between the two is controlled to be constant, the roll gap 3 may change due to the temperature and viscosity of the resin material, and the product thickness may fluctuate. There is also a problem that is not enough.

Further, the roll gap 3 between the rolls 1 and 2 is changed by the eccentricity of the roll support system or the shake of the machine even if the rolls 1 and 2 themselves are perfect circles. There is a problem that the thickness cannot be controlled.

The present invention has been made in view of the above-mentioned problems of the prior art. The thickness of the product can be made constant even if there is a change in the state of the inlet side such as the amount of banks, and the disturbance of the mechanical system etc. An object of the present invention is to provide a sheet thickness control method and apparatus in a calendar that can make the thickness of a product constant even if it exists.

[0009]

In order to solve the problems of the above-mentioned prior art, the sheet thickness control method for a calender according to the present invention is such that the support system between the rolls on the upstream side of the calender is deformed in the direction between the roll axes. The respective spring constants at that time are obtained, the rolling load due to the change of the inlet side state of the upstream roll is detected, and the deformation amount of the support system between the upstream rolls is obtained from this rolling load and the spring constant. It is characterized in that the amount of deformation is offset to control the roll gap to be constant.

Further, in the sheet thickness control method for the calender of the present invention, the spring constants when the support system between the rolls on the downstream side of the calender is deformed in the inter-roller axis direction are respectively calculated, and The rolling load due to the mechanical system disturbance is detected, the amount of deformation of the support system between the downstream rolls is obtained from the rolling load and the spring constant, and the amount of deformation is offset to control the roll gap to be constant. It is characterized by that.

Further, the sheet thickness control method for a calender according to the present invention detects the thickness of the product sent out between the most downstream roll of the calender and the take-off roll, and adjusts the rotation speed of the take-off roll to adjust the tension. Is controlled so as to keep the thickness constant.

In the sheet thickness control method for a calender according to the present invention, the spring constants when the supporting system between the rolls on the upstream side and the downstream side of the calender is deformed in the direction between the roll axes are determined in advance, and the upstream side is determined. Between the rolls, the rolling load due to the change in the entry side state is detected, the deformation amount of the support system between the upstream rolls is obtained from this rolling load and the spring constant, and this deformation amount is offset to keep the roll gap constant. On the downstream side, the rolling load due to the mechanical system disturbance between the rolls is detected, the deformation amount of the support system between the downstream rolls is obtained from this rolling load and the spring constant, and this deformation amount is While controlling to offset the roll gap to a constant value, the thickness of the product sent out between the most downstream roll and the take-off roll is detected, and the take-off roll rotation speed is adjusted. It is characterized in that the controls to a constant thickness by changing the tension Te.

Further, the sheet thickness control device in the calender of the present invention comprises a load detecting means for detecting the rolling load between the rolls on the upstream side of the calender and a roll gap adjusting means for adjusting the roll gap between the rolls on the upstream side. And the amount of deformation of the support system between the upstream rolls is calculated from the spring constant of this support system based on the detection value from the rolling load detection means due to the change of the inlet side state between the upstream rolls, and this deformation amount And an arithmetic processing means for outputting a control signal for canceling the above to a roll gap adjusting means on the upstream side.

Further, the sheet thickness control device in the calender according to the present invention comprises a load detecting means for detecting the rolling load between the rolls on the downstream side of the calender and a roll gap adjusting means for adjusting the roll gap between the rolls on the downstream side. When,
The deformation amount of the support system between the downstream rolls is calculated from the spring constant of this support system based on the detection value from the rolling load detection means due to the mechanical system disturbance between the downstream rolls, and the deformation amount is offset. And a processing signal for outputting a control signal for making the roll gap constant to the roll gap adjusting means on the downstream side.

Further, the sheet thickness control device in the calender according to the present invention comprises a thickness detecting means for detecting the product thickness sent from between the most downstream roll of the calender and the take-off roll, and the rotation speed of the take-off roll. Arithmetic processing for adjusting the rotation speed by the rotation speed adjusting means of the take-off roll based on the detection value from the adjusting means and the thickness detecting means to change the tension applied to the product to output a control signal for making the thickness constant. And means.

Further, the sheet thickness control device in the calender according to the present invention comprises a load detecting means for detecting the rolling load between the rolls on the upstream side and the downstream side of the calender, and a roll gap between the rolls on the upstream side and the downstream side. The roll gap adjusting means for adjusting the thickness of the product, the thickness detecting means for detecting the product thickness sent from between the most downstream roll and the take-off roll, the take-off roll rotation speed adjusting means, and the upstream roll. The deformation amount of the support system between the upstream rolls is calculated from the spring constant of the support system based on the detection value from the rolling load detection means due to the change of the entry side state of the roll, and the roll gap is offset by canceling the deformation amount. A control signal for making it constant is output to the roll gap adjusting means on the upstream side to detect the rolling load due to mechanical disturbance between the rolls on the downstream side. The amount of deformation of the support system between the downstream rolls is calculated from the spring constant of the support system based on the detection value from the means, and a control signal for canceling the amount of deformation and making the roll gap constant is provided on the downstream side. A control signal is output to the roll gap adjusting means, and further, based on the detection value from the thickness detecting means, the rotation speed adjusting means of the take-off roll adjusts the rotation speed to change the tension applied to the product to make the thickness constant. It is characterized by comprising arithmetic processing means for outputting.

[0017]

According to the sheet thickness control method in this calender, when the roll gap set to a constant value between the rolls on the upstream side changes depending on the inlet side state such as the bank amount and the resin state, the roll rolling load Since the support system is deformed due to the change, the amount of this deformation is detected as a change in rolling load, and based on this, the amount of deformation is calculated from the spring constant of the support system, and the roll gap is made constant so as to cancel it. The product thickness on the delivery side is kept constant.

Further, according to the sheet thickness control method for this calender, the mechanical system such as roll eccentricity or runout is provided between the rollers on the downstream side even if the product is controlled to have a constant thickness on the upstream side. If the roll gap changes due to the external disturbance, the thickness of the product will fluctuate.In this case as well, the mechanical system external disturbance is detected from the change in rolling load, and the amount of deformation is calculated from the spring constant of the support system based on this. The roll gap is controlled to be constant so as to offset this, and the product thickness on the delivery side between the rollers on the downstream side is made constant.

Further, according to the sheet thickness control method for this calender, the thickness of the final product on the calender delivery side is detected, and the pulling force applied by the take-off roll is adjusted to make the product thickness constant. I am trying.

Further, according to the sheet thickness control method for this calendar, the above-mentioned three controls are combined so as to prevent the thickness variation, and to obtain a high-quality product without uneven gloss.

Further, according to the sheet thickness control device in this calender, when the roll gap set at a constant between the rolls on the upstream side changes depending on the inlet side state such as the bank amount or the state of resin, roll rolling is performed. Since the supporting system deforms due to the change in load, the amount of this deformation is detected by the load detecting means as a change in rolling load, and based on this, the calculating means calculates the amount of deformation from the spring constant of the supporting system and cancels it. As described above, the roll gap adjusting means controls the roll gap to be constant, and the product thickness on the delivery side is made constant.

Further, according to the sheet thickness control device in this calendar, even between the rollers on the downstream side, even if the product is controlled to have a constant thickness on the upstream side, a mechanical system such as roll eccentricity or runout is generated. If the roll gap changes due to the external disturbance, the thickness of the product will fluctuate.In this case as well, the mechanical system external disturbance is detected from the change in the rolling load by the load detecting means, and based on this, the spring of the supporting system is detected by the arithmetic processing means. The roll gap adjusting means controls the roll gap to be constant so that the deformation amount is calculated from the constant and is offset, and the product thickness on the delivery side is made constant.

Further, according to the sheet thickness control device for this calender, the thickness of the final product on the calender delivery side is detected by the thickness detecting means, and the pulling force applied by the take-off roll is adjusted by the rotational speed adjusting means. Control is performed to keep the product thickness constant.

Further, according to the sheet thickness control device in this calendar, the variation of the thickness is prevented by combining these three devices, and it is possible to obtain a high quality product without uneven gloss.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. First, referring to FIG. 1, an embodiment of a sheet thickness control device for a calendar according to the present invention will be described.

The calender controlled by the sheet thickness control device 10 in this calender is of various types, but here, the calender arranged in an inverted L shape with four rolls will be described as an example. To do.

In the sheet thickness control device 10 in this calendar, three thickness controls are performed, and as the first control, the roll gap between the first roll 11 and the second roll 12, which is between the upstream rolls. And the third roll 13 and the fourth roll 1 which are between the rolls on the downstream side as the second control.
4 and the rotation speed control of the take-off roll 15 on the exit side of the fourth roll 14, which is the most downstream roller, are performed as the third control.

Therefore, the first roll 11 and the second roll 12
A load cell (load cell) 16 as a load detecting means for detecting the rolling load between the first and second rolls, and a load as a load detecting means for detecting the rolling load between the third roll 13 and the fourth roll 14 as well. A meter (load cell) 17 is provided.

Further, the hydraulic cylinder 18 as a roll gap adjusting means for adjusting the roll gap (roller axis distance) between the first roll 11 and the second roll 12 is the first.
The third roll 1 is provided on the axle box of the roll 11.
A hydraulic cylinder 19 serving as roll gap adjusting means is also provided in the shaft box of the fourth roll 14 between the third and fourth rolls 14 to adjust the roll gap (distance between roll axes).

Servo valves 20 and 21 are provided in these hydraulic cylinders 18 and 19 respectively to control the hydraulic oil supplied and discharged. Position detector 2 for detecting
2, 23 are provided.

Further, on the exit side of the take-off roll 15, a thickness gauge 24 as a thickness detecting means for detecting the thickness of the product.
The take-off roll 15 is connected to a servo motor 25 as a rotation speed adjusting means so that the rotation speed can be adjusted.

Controllers 26, 27, 28 serving as arithmetic processing means are provided for performing these three controls, and the controller 26 for the first control receives the detection signal of the load meter 16 and the detection signal of the position detector 22. The control signal is input from the output unit 31 to the servo valve 20 of the hydraulic cylinder 18 via the central processing unit (CPU) 30.
In the controller 27 for the second control, the detection signal of the load meter 17 and the detection signal of the position detector 23 are input to the input unit 29, and the servo valve 21 of the hydraulic cylinder 19 is supplied to the servo valve 21 via the central processing unit (CPU) 30. A control signal is output from the output unit 31. Further, in the controller 28 for the third control, the detection signal of the thickness gauge 24 is input to the input unit 29, and the control signal is output from the output unit 31 to the servo motor 25 of the take-off roll 15 via the central processing unit (CPU) 30. Is output.

In the sheet thickness control device 10 for such a calendar, the first and second control systems for controlling the roll gap are the first roll 11 and the second roll 12 as shown in the plan view of FIG. Between and the third roll 13
Between the second roll 14 and the fourth roll 14 are independently provided at both ends of each roll shaft box, or
One control system is configured to control both ends at the same time.

Next, the operation of the sheet thickness control device 10 in the thus constructed calender and the sheet thickness control method in the calender will be described. (1) Roll gap control between the first roll 11 and the second roll 12 This control is performed so that a constant sheet thickness is obtained when the sheet material passes (rolls) between the first roll 11 and the second roll 12. The gap between the rolls is adjusted with high response, and the sheet thickness and the bank state on the downstream side are kept constant.

The exit side sheet thickness between the first roll 11 and the second roll 12 of the calender is such that the roll gap is maintained at a constant value S0 in both the flow direction and the width direction, even if the roll gap is maintained at a constant value S0. The thickness h of the outlet sheet changes in the flow direction due to changes in the state of the inlet side material (top bank) (physical shape of the bank, temperature of the material, plasticity, etc.)
It also changes in the width direction and deteriorates product quality.

This is because the rolling force (roll load) changes on the roll-entry side, so that the supporting system supporting the rolls is deformed. Specifically, the first roll 11 and the second roll 12 are Frame 32 supporting the axle box
Is caused by a slight deformation and changes in the roll gap that should be held constant.

Therefore, if the spring constant of the mechanical system for generating the rolling force P (ton) between the first roll 11 and the second roll 12 is K (ton / mm), the delivery side sheet thickness h (m
m) is expressed by the following equation.

H = S0 + P / K where S0 is the initial roll gap, and the spring constant K of the mechanical system is the structure of the frame 32 and the first to fourth rolls 1
It differs depending on the arrangement of 1 to 14, etc., and is set in advance by measurement or simulation with an actual machine and input to the central processing unit 30 of the controller 26.

In this state, the state of the top bank and the material on the entry side changes, and if the rolling force changes by ΔP accordingly, the sheet thickness on the roll exit side also changes by Δh (mm). Can be shown as

Δh = ΔP / K Therefore, the thickness H (mm) of the exit side sheet at the time of the change of the entry side state can be expressed by the following equation 2 as follows.

H = h + Δh = S 0 + (P + ΔP) / K As is apparent from this equation, the rolling force P between the rolls and the variation ΔP thereof are obtained, and ΔP is obtained from the spring constant K obtained in advance.
By calculating / K by calculation, it is possible to know the change amount Δh of the sheet thickness, and if the initial roll gap S0 is corrected by this amount and offset, the roll gap is always kept constant. It will be possible.

Therefore, the rolling load fluctuation ΔP detected by the load cell (load cell) 16 is fed back to the position control system of the hydraulic cylinder for continuously adjusting the roll gap by dividing the value divided by the spring constant K, and the roll gap S0 When the sheet thickness is controlled, the sheet thickness H (mm) can be expressed as follows.

H = (S0-C * ΔP / K) + (P + ΔP) / K Here, C is a control constant, which is a disturbance of the mechanical system (such as roll eccentricity) or the state of the material on the roll-entry side. The value is set in consideration of various conditions such as the magnitude of change, but if this control constant C is set to 1, then H (c = 1) = S0 -1 * P / K = h, and the exit side sheet thickness There will be no change in H.

There is a relationship between the sheet thickness (gap) and the rolling load with respect to the value of the control constant C as shown in FIG. 4, and the spring constant K of the mechanical system is set so that the control constant C approaches 1 Is set so that the spring constant KE after control rises from the tilted state, the state change on the entry side ΔG
On the other hand, the change in the sheet thickness on the delivery side before the control becomes H1, but after the control, the change in the sheet thickness on the delivery side can be reduced to H2.

FIG. 3 is a block diagram showing the control of the sheet thickness in this case, and the value of the control constant C can be freely set between the first roll 11 and the second roll 12. If an appropriate value of the control constant C is determined by the ratio of the magnitude of the disturbance of the mechanical system (eccentricity of the first roll or the second roll) and the magnitude of the state change of the material on the roll entering side, It is possible to obtain a product with the smallest change in sheet thickness.

By thus offsetting the roll gap between the first roll 11 and the second roll 12 due to the change in rolling load, the roll gap can always be kept constant, and the product sheet The change in thickness can be prevented.

(2) Third roll 13 and fourth roll 14
Roll gap control between the third and fourth rolls because the thickness of the sheet becomes constant by passing between the first and second rolls and the change in the entrance side state between the third and fourth rolls is small. In order to prevent the thickness of the sheet passing (rolling) between the roll 13 and the fourth roll 14 from fluctuating due to disturbance of the mechanical system (roll eccentricity, etc.), the state along the entry side between the third and fourth rolls was set. The roll gap is controlled with high response.

The variation of the delivery side sheet thickness due to the mechanical system disturbance (roll eccentricity, etc.) possessed by the third roll 13 and the fourth roll 14 sets the mechanical system disturbance to be ΔSe, and the variation of the delivery side sheet thickness is Δhe. Then, it can be expressed by the following equation.

Δhe = ΔSe * K / (K + M) Here, as in the case of the control of (1), K is the spring constant of the mechanical system and M is the plastic constant of the material sheet.

As can be seen from this equation, if the plastic constant M of the material sheet is constant, the smaller the spring constant K of the mechanical system, the smaller the adverse effect of the disturbance ΔSe of the mechanical system.

Therefore, as one of the methods for reducing the spring constant K of this mechanical system, the third roll 13 and the fourth roll 1
It is conceivable to control the rolling force between 4 and 4 to be constant.
The value of the spring constant K of the mechanical system in this case is theoretically K = 0.
However, setting K to 0 is not necessarily a good idea considering the instability of the rolling state when the rolling forces at both ends of the roll (working side and driving side) are individually controlled.

On the other hand, when the thickness change ΔH (disturbance) of the sheet on the entrance side between the third roll 13 and the fourth roll 14 is not negligible as compared with the disturbance ΔSe of the mechanical system, the third roll 13 and the adverse effect ΔhM exerted on the sheet on the exit side of the fourth roll can be expressed by the following equation.

Δh M = M / (K + M) * ΔH From this equation, the larger the spring constant K of the mechanical system, the smaller the adverse effect of ΔH.

However, in the sheet thickness control method for this calendar, roll gap control is performed to keep the delivery side sheet thickness constant between the first and second rolls 11 and 12, and ΔH in the above equation is actually Therefore, the roll gap control of the third and fourth rolls is performed by the spring constant K of the mechanical system, the intrinsic disturbance ΔSe of the mechanical system,
Plastic constant M of entry side sheet, variation of entry side sheet thickness Δ
If the value of K can be freely controlled in consideration of H, the planned production schedule, etc., the highest quality sheet can be produced at that time.

A block diagram of the control of the sheet thickness in this case is as shown in FIG. 3 similarly to the case of the first and second rolls, and a uniform sheet thickness is provided between the first and second rolls. After the above is obtained, by setting the value of the control constant C to 0 or less (minus) between the third roll 13 and the fourth roll 14, no adverse effect due to the disturbance of the mechanical system,
A product having a uniform sheet thickness as obtained between the first and second rolls can be obtained.

Therefore, in actual control, this control constant C
If the sheet thickness on the entry side is constant between the sheet thickness (gap) and the rolling load with respect to the value of, there is the relationship as shown in FIG. The spring constant K of the mechanical system is tilted from the standing state to the spring constant KE after the control, so that before the control, the variation ΔS due to the disturbance of the mechanical system is output side. However, after the control, the fluctuation of the sheet thickness on the delivery side can be reduced to H4.

In this way, the roll gap between the third roll 13 and the fourth roll 14 due to the change of the rolling load due to the disturbance of the mechanical system is offset,
The roll gap can always be kept constant, and the change in the sheet thickness of the product can be prevented.

(3) Control by Takeoff Roll This control detects the thickness of the product sheet on the most downstream side of the calender and changes the tension by the takeoff roll to perform a draw control for keeping the sheet thickness constant.

Therefore, the thickness of the product delivered from between the fourth roll 14 which is the most downstream roll of the calender and the take-off roll 15 is detected by the thickness gauge 24, and the detected value is input to the input section 29 of the controller 28. Based on this, the central processing unit 30 calculates the rotational speed of the take-off roll for applying the tension to be applied to the sheet from the difference from the predetermined sheet thickness, and the output unit 31 rotates the rotational speed of the take-off roll 15. A control signal is output to the servo motor 25, which is an adjusting unit, to perform feedback control for adjusting the rotation speed.

In this calender delivery side sheet thickness control,
When the value detected by the thickness gauge 24 is larger than the set value and the sheet is thick, the peripheral speed of the take-off roll 15 is increased with respect to the peripheral speed of the fourth roll 14 so that a tensile force is applied to the sheet to reduce the sheet thickness. The thickness gauge 2
When the detected value at 4 is smaller than the set value and the sheet is thin, the peripheral speed of the take-off roll 15 is reduced with respect to the peripheral speed of the fourth roll 14 to reduce the tensile force applied to the sheet and increase the sheet thickness. To do so.

In this draw control, a limit value is set for the take-off roll speed correction amount, and when the limit value is likely to be exceeded, the roll gap of the calender is also controlled to break or loosen the product sheet. Prevent also.

By performing the above three controls (1) to (3) in combination and separately (single) on the left and right axle boxes of the roll,
Not only the thickness change of the sheet product in the sheet flow direction,
The thickness variation of the sheet product in the lateral direction is also reduced, and a high quality sheet product can be obtained.

In the above embodiment, the case where the left and right axial boxes are separately controlled has been described. However, when the accuracy of the width direction of the sheet product does not matter so much, the left and right axial boxes are set. You may make it control simultaneously.

Further, (1) and (2) of the above-mentioned embodiment may be rearranged according to the condition of the disturbance.

In the above embodiment, the calender provided with four rollers is the target, the upstream control targets are the first roll and the second roll, and the downstream control targets are the third roll and the fourth roll. However, in the case of a three-roller calender, the control objects on the upstream side are the first roller and the second roller, and the control objects on the downstream side are the second roller and the third roller. In the case of five rolls, the upstream control target is the first roll and the second roll, and the downstream control target is controlled by appropriately selecting a combination of two rolls such as the fourth roll and the fifth roll. In addition, the control on the upstream side or the downstream side may be applied in two stages, and this control is applied between all the rolls by a calender equipped with four, five or six rollers. You may do it.

Further, the format of the calendar is not limited to the inverted L-shape, but other formats can be applied.

Further, each constituent element may be modified within a range not changing the gist of the present invention.

[0068]

According to the sheet thickness control method for the calender of the present invention, as described in detail with reference to the above embodiment, the roll gap set between the upstream rolls has a constant roll gap. When it changes in the entry side condition such as the state, the support system deforms due to the change in the roll rolling load.Therefore, this deformation amount is detected as a change in the rolling load, and based on this, the deformation amount is calculated from the spring constant of the support system. Since the control is performed so that the roll gap is constant so as to cancel it out, the product thickness on the delivery side can be made constant.

According to the sheet thickness control method for a calendar of the present invention, between rollers on the downstream side, even if the product is controlled to have a constant thickness on the upstream side, a machine such as roll eccentricity or runout is produced. If the roll gap changes due to the system disturbance, the product thickness will change.In this case, too, the mechanical system disturbance is detected from the change in the rolling load, and based on this, the amount of deformation is calculated from the spring constant of the support system. Since the roll gap is controlled so as to cancel this, the product thickness on the delivery side between the rollers on the downstream side can be kept constant.

Further, according to the sheet thickness control method for a calender of the present invention, the thickness of the final product on the calendering side is detected and the pulling force applied by the take-off roll is adjusted to make the product thickness constant. Since this is performed, the product thickness can be made constant.

Further, according to the sheet thickness control method for the calendar of the present invention, these three controls are combined to prevent the variation of the thickness of the sheet product and to obtain a high quality product without uneven gloss. Obtainable.

Further, according to the sheet thickness control device in the calender of the present invention, when the roll gap set to a constant value between the rolls on the upstream side changes depending on the inlet side state such as the bank amount or the resin state, Since the supporting system is deformed by the change of rolling load, the amount of deformation is detected as the change of rolling load by the load detecting means, and based on this, the amount of deformation is calculated from the spring constant of the supporting system by the arithmetic processing means. Since the roll gap adjusting means controls the roll gap to be constant so as to cancel out, the product thickness on the delivery side can be made constant.

Further, according to the sheet thickness control device for the calender of the present invention, between the rollers on the downstream side, even if the product is controlled to have a constant thickness on the upstream side, a machine such as roll eccentricity or runout is produced. If the roll gap changes due to the system disturbance, the thickness of the product will fluctuate.In this case as well, the mechanical system disturbance is detected from the change in the rolling load by the load detection means, and based on this, the arithmetic processing means calculates the support system Since the amount of deformation is calculated from the spring constant and the roll gap is adjusted by the roll gap adjusting means so as to cancel it, the product thickness on the delivery side can be made constant.

Further, according to the sheet thickness control device for the calender of the present invention, the thickness of the final product on the calender delivery side is detected by the thickness detecting means, and the pulling force applied by the take-off roll is adjusted by the rotational speed adjusting means. Since the control is performed, the product thickness can be made constant.

Further, according to the sheet thickness control device in the calendar of the present invention, the combination of these three devices can prevent the variation of the thickness and can obtain a high quality product without uneven gloss, and It is possible to suppress fluctuations in the top bank, fluctuations in the sheet thickness due to changes in the viscosity of the material, and fluctuations in the sheet thickness due to mechanical disturbances (roll eccentricity, etc.), as well as fluctuations in the downstream bank.
The material of the sheet can be made uniform.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of a sheet thickness control device in a calendar according to the present invention.

FIG. 2 is a schematic plan view of an embodiment of the sheet thickness control device in the calendar of the present invention.

FIG. 3 is a block diagram of a control system according to an embodiment of a sheet thickness control method for a calendar according to the present invention.

FIG. 4 is an explanatory diagram of an upstream side control system according to an embodiment of a sheet thickness control method for a calendar according to the present invention.

FIG. 5 is an explanatory diagram of a downstream control system according to an embodiment of a sheet thickness control method for a calendar according to the present invention.

FIG. 6 is an explanatory diagram of a sheet thickness control method in a conventional calendar.

[Explanation of symbols]

 10 Sheet Thickness Control Device for Calender 11 First Roll (Upstream Roll) 12 Second Roll (Upstream Roll) 13 Third Roll (Downstream Roll) 14 Fourth Roll (Downstream Roll) 15 Takeoff Roll 16,17 Load meter (load cell) 18,19 Hydraulic cylinder (roll gap adjusting means) 20,21 Servo valve 22,23 Position detector 24 Thickness meter 25 Servo motor (rotation speed adjusting means) 26,27,28 Controller ( Arithmetic processing means 29 Input unit 30 Central arithmetic processing unit (CPU) 31 Output unit 32 Frame P Rolling force K Spring constant

Claims (8)

[Claims] 1. A spring constant when a support system between rolls on an upstream side of a calender is deformed in a roll axis direction is obtained in advance, and a rolling load due to a change in an inlet side state of an upstream roll is detected. A sheet thickness control method in a calendar characterized in that the amount of deformation of the support system between the upstream rolls is obtained from the rolling load and the spring constant, and the amount of deformation is offset to control the roll gap to be constant. . 2. A calender constant when the supporting system between the rolls on the downstream side of the calender is deformed in the roll axis direction is obtained in advance, and the rolling load due to mechanical disturbance between the rolls on the downstream side is detected. A sheet thickness control method in a calendar characterized in that the amount of deformation of the support system between the downstream rolls is obtained from the rolling load and the spring constant, and the amount of deformation is offset to control the roll gap to be constant. . 3. The thickness of the product delivered from between the most downstream roll of the calender and the take-off roll is detected,
A sheet thickness control method for a calender, characterized by controlling the rotational speed of a take-off roll to change the tension so as to keep the thickness constant. 4. A spring constant when the supporting system between the rolls on the upstream side and the downstream side of the calender is deformed in the direction between the roll axes, and the rolling load between the rolls on the upstream side due to the change of the entry side state The amount of deformation of the support system between the upstream rolls is determined from the rolling load and the spring constant, and the amount of deformation is offset to control the roll gap to be constant. The rolling load due to the mechanical system disturbance is detected, the amount of deformation of the support system between the downstream rolls is obtained from the rolling load and the spring constant, and the amount of deformation is offset to control the roll gap to be constant. On the other hand, the thickness of the product sent out between the most downstream roll and the take-off roll is detected, and the rotation speed of the take-off roll is adjusted to change the tension and control the thickness to be constant. Sheet thickness control method for a calendar. 5. A load detecting means for detecting a rolling load between rolls on the upstream side of the calender, a roll gap adjusting means for adjusting a roll gap between the rolls on the upstream side, and a change of the inlet side state between the rolls on the upstream side. While calculating the deformation amount of the support system between the upstream rolls from the spring constant of this support system based on the detection value from the rolling load detection means by,
A sheet thickness control device for a calender, comprising: a processing signal for canceling this deformation amount and outputting a control signal for making the roll gap constant to the roll gap adjusting means on the upstream side. 6. A load detecting means for detecting a rolling load between rolls on the downstream side of the calender, a roll gap adjusting means for adjusting a roll gap between the rolls on the downstream side, and a mechanical system disturbance between the rolls on the downstream side. Based on the detected value from the rolling load detection means, the deformation amount of the support system between the downstream rolls is calculated from the spring constant of the support system, and a control signal for canceling this deformation amount and making the roll gap constant is provided. A sheet thickness control device for a calender, comprising: an arithmetic processing unit that outputs the roll gap adjusting unit on the downstream side. 7. A thickness detecting means for detecting the thickness of the product delivered from between the most downstream roll of the calender and the takeoff roll, and a takeoff roll rotation speed adjusting means.
The processing means outputs the control signal for adjusting the rotation speed by the rotation speed adjusting means of the take-off roll based on the detection value from the thickness detecting means to change the tension applied to the product and make the thickness constant. A sheet thickness control device for a calendar characterized in that 8. A load detecting means for detecting a rolling load between rolls on the upstream and downstream sides of the calender, a roll gap adjusting means for adjusting a roll gap between the rolls on the upstream side and the downstream side, and a most downstream side. From the thickness detection means for detecting the product thickness delivered from between the roll and the take-off roll, the rotation speed adjusting means of the take-off roll, and the rolling load detection means due to the change of the inlet side state between the upstream rolls. The amount of deformation of the support system between the upstream rolls is calculated from the spring constant of the support system on the basis of the detected value of, and a control signal for canceling the amount of deformation and making the roll gap constant is provided with the upstream roll gap. Based on the detected value from the rolling load detection means due to mechanical disturbance between the rolls on the downstream side, the spring constant of the support system While calculating the amount of deformation of the support system between the flow side rolls, the control signal for canceling this amount of deformation and making the roll gap constant is output to the roll gap adjusting means on the downstream side, and further from the thickness detecting means. A calender, characterized in that it comprises arithmetic processing means for adjusting the rotational speed by the rotational speed adjusting means of the take-off roll based on the detected value to change the tension applied to the product to output a control signal for making the thickness constant. Sheet thickness control device.