JPH02165814A - Control of synchronizing position in looper - Google Patents

Abstract

PURPOSE:To prevent a strip from meandering without hindering the operation of a line by detecting a quantity of meander of the strip in a looper and controlling a synchronizing position in the looper in accordance with the quantity of meander detected. CONSTITUTION:In the control of the synchronizing position in the looper, e.g. when a detected quantity of meander exceeds a 1st quantity preset the synchronizing position in the looper carriage 3 is lowered inaccordance with the quantity of meander to shorten the length of a looper strand and to reduce the quantity of meander. As a result, when the quantity of meander is smaller than a 2nd quantity preset, the synchronizing position must by raised. When the transportation of the strip S on the inlet side is stopped on account of welding, etc., the control of the synchronizing position is stopped before the transportation is stopped to secure a quantity of storage of the looper strip. By this method the carrying speed of the strip S in the process part becomes stable.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a method for controlling the synchronized position of a looper, and more particularly, to a method for controlling the synchronized position of a looper in a continuous metal strip process line while preventing meandering of the metal strip within the looper. The present invention describes a looper synchronous position control method suitable for this purpose.

[Conventional technology]

Continuous process lines that continuously apply heat treatment, soaking treatment, pickling, etc. to metal strips such as steel strips have loopers before and after the processing section, and the strips that are passed through the loopers are stored. is common. The inlet looper of the process section sweeps out the stored strip to the subsequent process section during line inlet work such as welding, and the outlet looper sweeps out the stored strip to the subsequent process section during line outlet work such as shearing and coil removal. The processed strips are stored in the department. In this way, even if the conveyance of the strip stops at the input side or the output side of the line, the processing of the strip in the process section is not stopped. FIG. 4 shows an example of a general looper. In FIG. 6, a strip S is wound between the looper rolls indicated by reference numeral 1.2. A looper roll designated by numeral 1 is a fixed roll, and 2 is a movable roll. This movable roll 2 is integrated by a looper carriage 3, and is raised and lowered by rotating a winch 4 with a motor 5 and winding up and lowering a wire 6 connected to the looper carriage 3. . Note that 7 is a counterweight. In the looper, the strips S are stored as the looper carriage 3 moves up, and the stored strips S are swept out as the looper carriage 3 moves down. On the other hand, when there is no work on the entry and exit sides, that is, in a steady state, the speeds of the strips S before and after the looper are the same, and the looper carriage 3 is also stopped at a predetermined position. This position is called the synchronization position, and if it is an inlet looper, it is set to about 80 to 90% of the maximum carriage height, and if it is an outlet looper, it is set to about 10 to 20% of the maximum height of the carriage. It is generally set at the height.

[Problem to be solved by the invention]

Therefore, in a steady state, the strand length of the strip S in the inlet looper is large, and this strand length is small in the outlet looper.Therefore, there is almost no meandering in the strip in the outlet looper, but very little in the inlet looper. There is a problem in that meandering tends to occur. Further, the meandering of the strip S is not only caused by a defect in the shape of the strip, but may also be caused by an influence from a subsequent process section. In any case, if meandering occurs in the strip S, there is a risk that the strip S will break and the line will stop. Therefore, in order to deal with the meandering, when meandering occurs, lower the synchronization position of the looper, that is, shorten the strand length, continue operating in that state until the meandering falls within a predetermined range, and then, It is conceivable to perform an operation of returning to the original synchronized position. However, the operation of lowering the synchronization position to prevent such meandering is usually performed manually by an operator who intervenes in automatic operation, and this is one of the factors that prevents continuous process lines from becoming fully automated. was. Note that meandering of the strip is more likely to occur when the line speed is high, so if meandering occurs, there is a way to deal with it by leaving the synchronized position of the looper as it is and reducing the line speed, but if you use this method This is not a good idea because it hinders productivity and causes fluctuations in processing in the process section. The present invention has been made in view of the problems of the prior art, and is capable of preventing strip meandering without interfering with line operation, and eliminating manual intervention from looper operation to completely control the entire process line. An object of the present invention is to provide a method for controlling the synchronized position of a looper that enables automatic operation.

[Means to achieve the task]

The present invention detects the amount of meandering of the strip in the looper when controlling the synchronized position of a looper for storing and sweeping out strips to be passed through a process section in a process line, and detects the amount of meandering detected. The synchronous position of the looper is controlled according to the above, and when the conveyance of the strip is stopped at the input side of the line, the control of the synchronous position is stopped before the conveyance is stopped to reduce the amount of strip stored in the looper. By ensuring this, the above-mentioned problem has been achieved.

[Operation and effects of the invention]

In the present invention, in the method of controlling the synchronization position of a looper, the amount of meandering of a strip in the looper is detected, and the synchronization position of the looper is controlled according to the detected amount of meandering,
Prevent meandering. When controlling this synchronization position, for example, if the detected amount of meandering becomes larger than a first predetermined amount, the synchronization position of the looper carriage is lowered according to the amount of meandering, and the looper strand length is increased. The meandering amount is reduced by shortening the meandering amount, and as a result, the meandering amount is predetermined in the second
The synchronization position is raised when the amount becomes smaller than the amount. Further, when the strip conveyance on the line entrance side is stopped due to welding or the like, the control of the synchronization position is stopped before the conveyance is stopped to ensure the strip storage RX of the looper. As a result, the strip passing speed in the process section becomes stable. Therefore, meandering of the strip can be prevented without interfering with line operation, and the process line can be fully automated by eliminating manual intervention from looper operation.

【Example】

Embodiments of the present invention will be described in detail below with reference to the drawings. This embodiment is a device that controls the synchronization positions of loopers provided before and after a process section. Since this synchronous position control device is the same before and after the process section, the configuration of the control device for one looper is shown in FIG. 1, and illustration of the looper and its control device is omitted. The control system of the control device is shown in FIG. As shown in FIG. 1, in this synchronous position control device, a meandering amount detector 8 for detecting the meandering tp of the strip S is provided on the strand in the exit direction of the looper, and the detection signal of the meandering fP of this detector 8 is , are input to the looper synchronous position controller 9. The controller 9 also has an inlet speed VE (m
/min) and the center speed (corresponding to the speed of the strip S in the process section) V o (Il/l1in) are also input. The controller 9 controls the input meandering amount P and entrance speed v.
Based on E and the center speed V□, a control signal for the looper carriage 3 is input to the carriage motor controller 12 in order to control the synchronization position according to the timing described later. The carriage motor controller 12 controls the carriage motor 5 based on the input control signal, drives the carriage 3, and controls its vertical position and synchronization position. Note that the looper synchronous position controller 9 outputs a correction value ΔVεref for the entrance speed command. This correction value ΔVεref is determined by the strip S fed into the looper when the carriage 3 moves up and down.
Since it is necessary to compensate by increasing or decreasing the speed of
It is output to correct the speed. Next, the control contents of the synchronous position control device will be explained based on FIGS. 1 and 2. Now, the input side work of the line such as welding the strip S has been completed, and the operation of the input side equipment has been started to accelerate the conveyance speed of the strip S, and the strip storage in the looper, which had been reduced until then, has been completed. Let's say you start increasing the amount. At this time, the speed command Vc to the looper carriage 3 is given by the following equation <1), as shown by the symbol A in FIG. Vc=(VE-VD)/N (1) Here, N is the number of strands in the looper. During normal operation, the speed VC of the looper carriage 3 is controlled based on this equation (1), and the central portion speed Vo is set as the target speed while ensuring the amount of strip stored. In addition, when raising the looper carriage 3, an upper limit value is set so that the position of the carriage 3 does not exceed the rising end to ensure safe operation of the looper. Further, the synchronization position control for preventing meandering in the position control device is executed when the following conditions are satisfied. (I) Welding completed. (]I)VE-Vo≧O-(2> If the conditions (1) and (IF) are satisfied,
As shown by reference numeral B in FIG. 2, a command is given to set the correction amount of the synchronization position, and if it is not satisfied, a reset is commanded. When the setting of the correction value is instructed, the meandering amount detector 8 detects the meandering iP<ml) of the strip S, as indicated by the symbol C in FIG. When the meandering amount P exceeds the upper limit threshold pu as shown in the following equation (3), the synchronization position is lowered by a predetermined correction amount and the looper carriage 3 is lowered. P≧pu... (
3) As a result of the lowering, if the strip meandering amount P becomes equal to or less than the lower limit threshold Pb as shown in the following equation (4), the synchronization position is raised by a predetermined correction amount and the looper carriage 3 is raised. P≦Pb... (4
) The synchronization position command determined as above is the actual position H (
1) is fed back to the carriage motor controller and controls the vertical position of the looper carriage 3. Here, for example, the upper limit pu is ioomi, the lower limit (i
Pb can be set to 50u. Further, K 1 and K 2 in FIG. 2 are constants, and by setting these values, the respective correction amounts for upward movement and downward movement can be adjusted. As the meandering is continuously controlled in the manner described above, the time to start the next entry-side work approaches, and by this time the position of the carriage 3 has been raised to the maximum in order to secure the storage amount of the strip S. It is necessary to keep it. Therefore, at this time, the looper synchronous position control performed as described above is stopped. The timing at which this synchronous position control is stopped is when the following equation (5) is satisfied, which takes into account the amount of strips S stored in the looper. (Hu H)・N+(Vo/60)・t+
<1/2>・'(Vo/60) ・(VD/(
2)≧Lr・
... (5) Here, H is the actual vertical position (II) of the looper carriage 3, Hu is the original synchronous position (IIl) of the looper carriage 3, and α is the acceleration/deceleration rate on the line entry side (i
/sea'), Lr is the remaining coil length (II) in the payoff reel on the line entry side. In addition, t is the time measured retroactively from the start of the work, indicating when to stop the synchronous position control before the start of the input side work (
sec) and is determined as follows. That is, when the following equation (6) holds true, the time t is found using the following equation (7), and when the following equation (8) holds, the time t is found using the following equation (9). (Hu-H) −N< (V, εmax'/<6
0- a) 1...(6) t=2・'u-H)・N/α...(7)(HU-
H)-N≧(vEl'1lax'/(60-α))・
...(8) t = 2VEllaX / a + ((Hu-H) ・ N -VEmax '/ (60-α)) / (VEnax
/60) -(9>Here, V E l1ax is the maximum speed on the entry side. Next, the control state when the synchronization position of the looper is controlled according to the present invention will be explained in detail based on the time chart in Fig. 3. In this case, as shown by the solid line in Fig. 3 (A), the synchronized position command of the looper carriage was output. The amount of meandering detected in Figure 3 (C) is shown, and the correction amount of the synchronization position is as shown in Figure 3 (D>). As shown in Figure 3 (B), during line entry side work, The speed command is zero, and when accelerating on the entry side after that work,
When the input side speed and the process section speed become equal, the looper synchronous position control according to the present invention is turned on as shown in FIG. 3(C). At this time, if the looper synchronous position command is in a state where there is no meandering, the looper is raised in accordance with the ideal synchronous position command shown by the broken line in FIG. 3(A). However, usually
Since meandering occurs, meandering fiP from meandering detector 8
Based on the feedback, as shown in Fig. 3 (C) and (D), when meandering exceeding a certain threshold (threshold on the looper lowering command side) occurs, another threshold is set in the direction of lowering the synchronized position command of the looper. When the meandering amount falls below the (looper rising side threshold), an appropriate correction amount is determined in the direction of increasing the looper synchronization position command, and the synchronization position is controlled. On the other hand, when the next entry-side work approaches, it is necessary to raise the looper to its maximum raised position or to its original synchronous position for that work. To do this, use equation (7) or equation (9) above to calculate when to start ascending from the current looper position, and then turn off the synchronous position control at the calculated time. Output the command. This is because if the carriage were lowered after this point, the looper would have less strip storage than would be needed for the entry operation. Next, the strip is sent out from the looper, and after the entry side work is completed, as shown in FIG.
, (n), the synchronous position control is turned on again.

[Brief explanation of the drawing]

FIG. 1 is a block diagram including a partial layout showing the configuration of a looper and a synchronous position control device according to an embodiment of the present invention; FIG. 2 is a block diagram showing a control system of the synchronous position control device; FIG. 3 is a time chart for explaining the control situation of a looper to which the present invention is applied, and FIG. 4 is a layout diagram showing the configuration of a general looper. 2... Carriage motor controller.

Claims (1)

[Claims] (1) In the process line, when controlling the synchronized position of the looper for storing and sweeping out the strip to be passed through the process section, the amount of meandering of the strip in the looper is detected, and the method is applied according to the detected amount of meandering. to control the synchronous position of the looper, and when the conveyance of the strip stops at the input side of the line, the control of the synchronous position is stopped before the conveyance stops to ensure the strip storage amount of the looper. A method for controlling the synchronous position of a looper, characterized in that: