JPH0534088B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device for automatically decelerating and stopping a reverse type rolling mill in response to the end portion of a material to be rolled. The present invention relates to an automatic speed reduction device that improves rolling efficiency by shortening the time required for each pass.

[Prior Art] In general, a reverse type rolling mill has a material to be rolled 5 wound between a pair of reels 1 and 2 as shown in FIG. 1, and the material to be rolled 5 is reciprocated between these reels 1 and 2. The material to be rolled 5 is rolled by the work rolls 4.
It is configured to roll. Note that 3 is a deflector roll, and the rolled material 5 is guided by these deflector rolls 3.

In such a rolling mill, it is necessary to decelerate and stop the material 5 to be rolled at a predetermined position at the end of the material 5 to be rolled, and to reverse the running direction of the material 5 to be rolled. Generally, in a rolling mill, the deceleration rate at the time of stopping is constant, and the deceleration rate is known in advance for each reduction gear. Therefore, calculate the length of the rolled material that will run during deceleration from the rolling speed, etc., start deceleration at a position that takes this length into consideration, and stop at a predetermined stopping position of this rolled material. It performs so-called feedforward control that stops the engine at any time. However, since there is an error in detecting the number of windings on the reel, the running of the material to be rolled may not stop even when it reaches a predetermined stop position. Unrolled thick parts may get caught between the work rolls 4 and damage the device. In order to prevent such dangers, deceleration is started early with a predetermined safety margin in mind, and once the speed has been reduced to the predetermined low adjustment speed, the rolling mill is operated at this speed to absorb the error and reduce the reel speed. When the number of remaining windings corresponds to the length of the rolled material that is traveled from this low adjustment speed until it stops, deceleration is started and the rolling material is stopped at a predetermined position.

FIG. 2 shows the above operating state. That is, first, this rolling mill is accelerated between points a and b, and then the rolling speed is set to a predetermined rolling speed V between points b and c.
Rolling is carried out at step 2, deceleration is started from point C taking into account the safety margin S, and at point d, where the rolling mill has been decelerated to low speed adjustment speed V1, this rolling mill is operated at this speed for low speed adjustment, and from a predetermined stopping position. At point e, when the vehicle reaches a position ahead by the distance traveled from this low adjusted speed until it stops, deceleration is started again, and the vehicle is brought to an accurate stop at a predetermined stop position, point f.

Conventionally, this kind of operation was often performed by intuition by the rolling mill operator, and as a result, the safety margin S became longer than necessary, the time for this low-speed adjustment operation was extended, and the There was a problem that the time required was longer and the efficiency of the rolling operation was lowered.

In order to eliminate such problems, there is also a device that automatically operates the rolling mill to prevent the safety margin S from becoming unnecessarily long. However, there is a limit to improving the accuracy of detecting the number of remaining windings of the reel, and there is a limit to reducing the safety margin S.

Furthermore, there is also one in which the position of the rolled material 5 is detected by the rotation of the deflector roll 3, and the accuracy of the position detection is improved. However, slippage may occur between the deflector roll 3 and the rolled material 5, resulting in low reliability.

[Problems to be Solved by the Invention] The present invention aims to provide an automatic deceleration device for a rolling mill that can shorten the time required for deceleration, improve the efficiency of rolling work, and ensure sufficient safety. purpose.

[Means for Solving the Problems] The present invention provides a device that automatically decelerates and stops a reverse rolling mill in response to the end of a rolled material during rolling, which detects the rotation of a reel and A winding number detector detects the remaining number of windings of the material to be rolled that is being unwound from the rolling machine, and the number of windings that will be unwound before the rolling mill stops is determined by receiving a signal from this winding number detector. When the number of turns with a predetermined first safety margin is reached, the rolling mill starts to decelerate, and during this deceleration, the rolling mill is once operated at an intermediate adjustment speed lower than the rolling speed of the material to be rolled. However, the number of remaining turns on the reel has reached the number of turns that takes into account a second safety margin, which is smaller than the first safety margin, in the number of turns to be unwound from this intermediate adjustment speed until this rolling mill stops. If the rolling mill starts decelerating again, and during this deceleration it reaches the final low adjustment speed that is lower than the intermediate adjustment speed, operate this rolling mill again, and if the remaining number of turns on the reel reaches this low speed. The rolling mill is equipped with a control circuit that starts decelerating the rolling mill when the number of rolls to be unrolled from the adjusted speed to the time of stopping is reached.

[Operation] Intermediate adjustment operation is performed at the above-mentioned intermediate adjustment speed from the start of deceleration until reaching the low adjustment speed, and since this intermediate adjustment speed is lower than the rolling speed, deceleration is started again from this intermediate adjustment speed. The second safety margin is shorter than the first safety margin. Therefore, as shown in FIG. 4, the length of the rolled material (corresponding to the area within the solid line in FIG. 4) that travels from deceleration to stop becomes longer than in the past. Therefore, the time point at which this deceleration starts can be made earlier by this amount, the time required for one pass can be shortened, and the efficiency of the rolling operation can be improved. Further, the second safety margin is shortened in accordance with the intermediate adjustment speed, and the safety can be sufficiently ensured as in the conventional case.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 3 and 4. In the figure, reference numerals 11 and 12 indicate reels, and a rolled material 5 such as a thin metal plate is wound around these reels 11 and 12. The material to be rolled 15 is passed between these reels 11 and 12.
is configured to travel back and forth and be rolled by work rolls 14. Note that 13 is a deflector roll, and the rolled material 15 is guided by these deflector rolls 13.
Then, the material to be rolled 15 is stopped at a predetermined position of its end portion corresponding to the work roll 14 and reversed. In addition, in this stopped state, the end portion of this rolled material 15 is wound around several times on the reels 11 and 12 on the unwinding side, but in this stopped state, the number of turns on this reel is zero. Set.

The rotations of these reels 11 and 12 are detected by winding number detectors 16, respectively. These winding number detectors 16 are connected to the reels 11 and 1 described above.
The number of turns of the material 15 to be rolled is measured and memorized, and the number of rotations of the reel is detected when the material 15 to be rolled is unwound from the reel. It is configured to calculate the number of remaining turns. As described above, these winding number detectors 16 detect that the winding number of this reel is zero when a predetermined position of the end portion of the material to be rolled 15 corresponds to the work roll 14 described above.

Signals from these winding number detectors 16 are sent to a control circuit 17. The control circuit 17 controls the operation of the rolling mill as shown below in response to the signals from the winding number detector 17, and automatically decelerates and stops the rolling mill.

First, as shown in FIG. 4, while the rolling material 15 is being operated at the rolling speed V2, the remaining number of turns of the material 15 to be rolled is decelerated from the rolling speed V2 and before the material 15 is stopped. When the rolling length reaches the number of turns with a predetermined first safety margin S1 in the running length, a deceleration signal is output from the control circuit 17, and the deceleration of the rolling mill is started at the deceleration start time Tb at point C in FIG. Begins. Then, the speed of this rolling mill is an intermediate adjustment speed V that is lower than the above-mentioned rolling speed V2.
3 (point c' in Figure 4), the rolling mill is operated at this intermediate adjustment speed V3. During this intermediate adjustment operation, the remaining number of windings of the reel reaches the number of windings that takes into account a predetermined second safety margin S2 for the length that the reel will travel before decelerating and stopping from this intermediate adjustment speed V3. After that (point d' in Figure 4), the rolling mill is decelerated again. This second safety margin S
2 is set corresponding to the above-mentioned intermediate adjustment speed V3, and is smaller than the above-mentioned first safety margin S1 corresponding to the above-mentioned rolling speed V2, but since this intermediate adjustment speed V3 is smaller than the rolling speed V2, , sufficient safety is ensured even with this second safety margin S2.

Then, the rolling mill is decelerated in this manner, and when this speed is reduced to the final low adjusted speed V1 (point d'' in FIG. 4), the rolling mill is operated again at this low adjusted speed V1. During this low-speed adjustment operation, when the number of remaining windings of the reel reaches the number of windings that corresponds to the length that will be traveled before decelerating from this low-speed adjustment speed V1 and stopping (point e in Figure 4), ) This rolling mill is decelerated and brought to a predetermined stopping position (f in Figure 4).
Stop at point). Note that this final low-speed adjustment speed V1 is set to a sufficiently low speed that the required safety margin is zero, that is, the vehicle can be stopped safely and accurately even without the safety margin.

In the above deceleration operation, the deceleration start time
The length that the rolled material 15 travels from Tb to the stop time Te' corresponds to the area of the portion below the lines c, c', d', d'', e, and f. Therefore, as is clear from FIG. 4, when decelerating as in this embodiment, the rolling speed and the time from the start of deceleration to stopping are shorter than in the conventional case under the same conditions. Even if it does, it will travel a long distance corresponding to the area of c', d, d'', and d'. Therefore, the start time Tb' and stop time Te' of the deceleration and stop can be shortened by an amount corresponding to this amount, and the time required for one pass can be shortened to improve the efficiency of the rolling operation. .

Further, the second safety margin S2 is the first safety margin S
Although it is set shorter than 1, the intermediate adjustment speed V3
Since the rolling speed V2 is lower than the rolling speed V2, safety does not deteriorate.

Note that if the intermediate adjustment speed V3 is too large or too small, the time reduction effect will be reduced. This intermediate adjustment speed V3 is such that the rolling speed V2 is, for example, 300.
m/min, the range of V3=0.25 to 0.5V2 is preferable, and the above-mentioned low speed adjustment speed V1
It is preferable that the speed is such that the motor can be stopped at a predetermined position sufficiently safely without allowing for a safety margin, for example, in the range of V1=0.05 to 0.15V2.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the configuration of a conventional reverse type rolling mill, and FIG. 2 is a diagram showing the conventional operating state.
FIG. 3 is a schematic diagram of an embodiment of the present invention, and FIG. 4 is a diagram illustrating a deceleration operation of an embodiment of the present invention. 11, 12... Reel, 13... Deflector roll, 14... Work roll, 15... Rolled material, 16... Winding number detector, 17... Control circuit.

Claims (1)

[Claims] 1. A device that automatically decelerates and stops a reverse rolling mill in response to the end of a rolled material during rolling, which detects the rotation of a reel and determines the number of remaining turns of the rolled material unwound from this reel. A number of turns detector detects the number of turns, and a signal from this number of turns detector is received, and the number of remaining turns is determined to be the number of turns that takes into account the number of turns to be unrolled before the rolling mill stops, plus a predetermined first safety margin. When the rolling speed is reached, the rolling mill starts decelerating, and during this deceleration, the rolling mill is once operated at an intermediate adjustment speed lower than the rolling speed of the material to be rolled, and the number of remaining turns of the reel reaches this intermediate adjustment speed. When the number of rolls to be unrolled before the rolling mill stops reaches the number of rolls that takes into account a second safety margin smaller than the first safety margin, the rolling mill starts decelerating again. When the final low adjustment speed, which is lower than the intermediate adjustment speed, is reached during deceleration, the rolling mill is operated again, and the remaining number of turns on the reel reaches the number of turns that will be unrolled from this low adjustment speed until it stops. 1. An automatic deceleration device for a rolling mill, comprising: a control circuit that starts deceleration of the rolling mill when the rolling mill is activated.