JPS6251685B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rolling control device for a rolling mill equipped with a looper between two rolling mills.

Conventionally, there has been a device of this type as shown in FIG. In Fig. 1, 1 and 2 are the second and third rolling mills, and 3 is the second rolling machine being transferred in the direction of the arrow.
A rolling mill 4, which is sequentially rolled by the third rolling mills 1 and 2, is installed between the second and third rolling mills 1 and 2, and is related to the tension of the rolled material 3 and the driving force that pushes it up from below. A looper 5 is a control device that rolls the rolled material 3 at an angle θ formed by the looper.

In the control device 5, 6 is a detector that detects the angle θ of the looper 4, and 7 is an output according to the angular deviation between the angle θ given by the signal 6a of the detector 6 and the set target angle θ*. A looper angle controller 8 obtains a signal 7a consisting of the deviation ΔV of the rolling speed, and 8 follows the signal 7a of the looper angle controller 7.
A drive circuit drives the second rolling mill 1 with a polarity that reduces the angular deviation, and 9 is a drive device that presses the looper 4 against the rolled material 3 to form an angle θ.

Next, the operation will be explained. When the rolled material 3 is bitten by the third rolling mill 2 following the second rolling mill 1, the drive device 9 drives the looper 4 and contacts the looper 4 with its tip to push up the rolled material 3. Material 3
An angle θ is formed using the tension as a reaction force, so that the tension in the rolled material 3 becomes a predetermined value.

If the tension of the rolled material 3 exceeds a predetermined value, the reaction force of the rolled material 3 against the looper 4 will increase, and the looper 4 will be pushed down and the angle θ will become smaller, and conversely, the tension of the rolled material 3 will increase. When the value is below a predetermined value, the reaction force of the rolled material 3 against the looper 4 becomes smaller, so that the angle θ resulting from the looper 4 pushing up the rolled material 3 becomes larger. By increasing and decreasing the angle of the looper 4 in this manner, the tension of the rolled material 3 is controlled to be constant. Further, when the tail end of the rolled material 3 reaches a predetermined position upstream of the second rolling mill 1 and time t ₁ shown in FIG. 2 arrives, the target angle θ* of the looper 4 is changed from the previous angle θ ₁ Angle θ ₂ from
(<θ ₁ ), the operating angle θ of the looper 4 is made small, and the rolling material 3 is on standby so that the tail end portion of the rolled material 3 can be stably passed through. Generally, the operating angle θ of the looper 4
If the tail end is threaded while the
Since the phenomenon of tail end splashing and tail end squeezing is likely to occur, the operating angle θ of the looper 4 is made small as described above during standby. Further, at time _t2 just before the tail end of the rolled material 3 passes through the second rolling mill 1, the looper 4 is moved to the lower limit angle θ of its operating angle.
₃ , and then the tail end of the rolled material 3 reaches the second
After passing through the rolling mill 1 and the third rolling mill 2, the rolling is completed.

However, in the period after the tail end of the rolling mill 3 passes through the first rolling mill (not shown) located upstream of the second rolling mill 1, the load on the second rolling mill 1 suddenly decreases. Therefore, the rolling speed of the second rolling mill 1 increases rapidly, and as a result, as shown in FIG. 3, the time when the tail end of the rolled material 3 passes through the first rolling mill (time t ₁ in FIG. 3) A phenomenon occurs in which the operating angle θ of the looper 4 rapidly increases from time t ₂ (time t ₂ shown in FIG. 3) onward to time t ₂ (time t 2 shown in FIG. 3).

That is, the looper angle controller 7 controls the looper operating angle θ to the angle θ ₂ as described above to control the rolled material 3.
However, due to the sudden disturbance caused by the sudden decrease in the rolling mill load, the looper angle control could not sufficiently control the rapid increase in the looper angle θ. As shown in FIG. 3, the looper angle θ increases rapidly, and the looper angle becomes large, which adversely affects the stable threading of the tail end of the rolled material.

As described above, in the conventional rolling control device, the looper angle increases rapidly in the period after the tail end of the rolled material passes through the first rolling mill located on the upstream side, and the threading of the tail end of the rolled material becomes impossible. There was a drawback of stability.

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional method, and by preventing the looper angle from rapidly increasing in the transitional state where rolling ends, it indirectly suppresses the backlash and stabilizes the roll. It is an object of the present invention to provide a rolling control device that can perform rolling control.

The present invention is a rolling control device for a rolling mill having first, second and third rolling mills arranged along the traveling direction of rolled material, the rolling control device being installed between the second and third rolling mills. The looper angle of the rolled material is compared with a set target angle to detect an angular deviation, and the second rolling mill is operated in a period after the tail end of the rolled material passes the first rolling mill. A control signal is obtained in which the angular deviation is corrected by a set value for reducing the rolling speed of the second rolling mill, and the rolling speed of the second rolling mill is driven to be corrected in accordance with the value of this control signal.

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 4, which shows this invention in a block diagram, 1 to 9 are the same parts as shown in FIG.
a setting device that is provided to set the rolling speed of the second rolling mill 1 and outputs a signal Δr as a set value;
10a is a relay contact that guides the signal Δr, and 11 is an adder that adds the signal 7a of the comparator 7 and the signal Δr. The signal 11a of the adder 11 is a signal obtained by offseting the deviation ΔV by the signal Δr, and is supplied to the drive circuit 8.

Next, the operation will be explained. The contact 10a is kept open by a circuit (not shown) until the tail end of the rolled material 3 passes through a first rolling mill (not shown) located upstream of the second rolling mill 1. In such a state, the signal 11a of the adder 11 is equal to the signal 7
It is a itself. Therefore, the rolling speed of the second rolling mill 1 is controlled only according to the angle θ of the looper 4.

Thereafter, when the contact 10a is closed, the adder 1
The signal 11a of 1 is the sum of the signal 7a and the signal Δr. Therefore, the rolling speed of the second rolling mill 1 is reduced by an amount corresponding to the increase in the signal Δr. That is, when the bottom of the rolled material 3 occurs in the first rolling mill upstream of the second rolling mill 1, the rolling speed of the second rolling mill 1 is lowered according to the signal Δr.
As a result, even if the rolled material 3 passes through the rolling mill on the upstream side of the second rolling mill 1, the rolling speed is reduced, so that the rolling speed of the second rolling mill 1 is reduced by reducing the load on the rolling mill 1. A sudden increase in speed is suppressed or alleviated, and a sudden increase in the angle θ of the looper 4 is suppressed.

Note that the setting device 10 is set to obtain an optimal setting value according to the rolling speed, the material of the rolled material, the plate thickness, the plate width, and the like.

FIG. 5 is a block diagram showing another embodiment of the invention. In Fig. 5, 12 is the target angle θ
* and the signal 6a of the detected angle θ to check for excessive reduction in rolling speed, and calculate the deviation θ - θ*
A comparator that outputs a signal 12a when (θ<θ*) becomes negative; 13 is a relay that closes contact 13a and opens contact 13b when driven by signal 12a; 14 is a signal Δr from setting device 10; is the coefficient α(0
This is a multiplier that multiplies by ≦α<1). The signal Δr is supplied to the adder 11 via contacts 13b and 10a, and the signal 14a of the multiplier 14 is supplied to the contacts 13a and 10a.
It is supplied to adder 11 via 10a.

The operation shown in FIG. 5 will be explained. In the first case,
If the deviation θ-θ* is positive, the contact 13b is closed, so when the contact 10a is closed, the signal Δr from the setting device 10 is supplied to the adder 11 via the contacts 13b and 10a. Ru. As a result, the adder 11 supplies the driving device 8 with the sum of the deviation ΔV and the signal Δr.

In the second case, if the deviation θ-θ* is negative, the comparator 12 outputs the signal 12a to operate the relay 13 and close the contact 13a, and when the contact 10a is closed. A signal 14a from the multiplier 14 is supplied to the adder 11 via contacts 13a and 10a. As a result, the adder 11 supplies the driving device 8 with the sum of the deviation ΔV and the signal 14a. Since the signal 14a is the signal Δr multiplied by α, in the second case, the rolling speed is prevented from decreasing excessively and the rolling speed of the rolling mill 1 is prevented from decreasing too much.

As described above, according to the present invention, in the first, second and third rolling mills arranged according to the rolling flow, the second rolling mill is arranged according to the angle of the looper between the second and third rolling mills. In addition to controlling the rolling speed of the first rolling mill, when the rolled material passes through the first rolling mill, the rolling speed of the second rolling mill is reduced, so that the rolled material does not pass through the first rolling mill. In the subsequent period, the rolling speed of the second rolling mill increased rapidly,
As a result, it is possible to quickly and accurately suppress a sudden increase in the angle of the looper, and the threading of the tail end of the rolled material can be stabilized.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventional rolling control device, FIGS. 2 and 3 are diagrams explaining the operation of the looper, FIG. 4 is a block diagram showing a rolling control device according to an embodiment of the present invention, and FIG. The figure is a block diagram showing another embodiment of the invention. 1, 2...Rolling machine, 3...Rolled material, 4...Looper, 7, 12...Comparator, 8, 9...Drive device,
11... Adder, 13... Relay, 14... Multiplier. In addition, in the figures, the same reference numerals indicate the same parts.

Claims (1)

[Scope of Claims] 1. A rolling control device having first, second and third rolling mills arranged along the traveling direction of the rolled material, including a looper installed between the second and third rolling mills. a looper angle controller that compares the angle of the looper with a set target angle and outputs a signal for correcting the rolling speed of the second rolling mill according to the angular deviation; a setting device that outputs a setting value that closes a contact when passing through the first rolling mill to reduce the rolling speed of the second rolling mill by a predetermined amount; and a setting device that outputs a setting value that reduces the rolling speed of the second rolling mill by a predetermined amount; an adder for adding the setting value outputted from the setting device to a signal to be corrected; and the second rolling mill for correcting the rolling speed of the second rolling mill in accordance with the output of the adder. A rolling control device comprising a drive circuit for driving. 2. The setting device directly outputs a setting value for reducing the rolling speed of the second rolling mill when the angular deviation is a positive value during a period after the tail end of the rolled material passes through the first rolling mill. and, when the angular deviation is a negative value, a selection circuit that guides to the output terminal another set value obtained by multiplying the set value by a predetermined coefficient. The rolling control device described.