SU865455A2 - Rolled stock thickness automatic control apparatus - Google Patents

Description

I.

The invention relates to functional schemes for the automatic control of sheet metal rolling stock and can be used in automatic control systems for the operation of rolling mills.

According to the main author, No.-789174, a device for automatically adjusting the thickness of rolled products is known, which allows adjusting the dead zone as a function of metal pressure on the rolls and eliminating it completely after the actuator starts moving, thus increasing the accuracy of adjusting the thickness of the CQ strip.

However, the effect of increasing the accuracy of adjusting the thickness of the strip of the device decreases as the rolling force increases, since the dead zone in this device reaches its maximum value at maximum rolling forces.

The purpose of the invention is to further improve the accuracy of adjusting rolled products.

The goal is achieved by the fact that the proposed device additionally contains a multiplication unit, an adder, a reference source, a large-scale converter, the input of the large-scale Converter is connected to the output of the rolling force sensor, the output of the large-scale converter and the output of the reference source are connected respectively to the first and second inputs of the adder, the output of which is connected to the first input of the smart $ 1 block, the second input of the multiplying block is connected to the output of the control signal generating unit, the output of the smart block The unit is connected to the input of the control signal module and

20 second entry key.

Additional blocks and connections allow greater control of thickness control by adjusting the gain of the thickness control channel as the rolling force changes.

Introduction of an adder to the device, to the first and second inputs of which signals are received from the output of the scaler converter and the output of the reference source and multiplication unit, respectively, the first input of the second is connected to the output of the adder, allows you to adjust the gain factor of the thickness regulator, and the increase in the gain coefficient torus thickness with increasing rolling force simultaneously with an increase in the width of the dead zone leads to the fact that reduced to an error in the thickness of the strip, the width of the insensitive zone The mass regulator remains virtually unchanged (minimal) for any rolling effort.

This contributes to an increase in the accuracy of the strip thickness control. In this case, the stability of the device is not broken, so. as with the growth of the rolling force. The moment of resistance on the driveshaft shaft increases.

The drawing shows a functional diagram of the device for automatic adjustment of the thickness of the car.

The device comprises a control signal generation unit 1, the first 2 and second 3 elements of the comparison are connected to the first and second inputs of which. The first input of the first element 2 of the comparison is connected to the output of the sensor 4 position of the pressure screw, the second input of the first element 2 is compared with the output of the setpoint adjuster 5 of the pressure screw 6 acting on the cushions of the support rolls 7 of the rolling stand, which includes the work rolls 8. The first input of the second comparison element 3 is connected to the output of the rolling force sensor 9, the second input of the second comparison element 3 is connected to the output of the rolling force setting 10.

The first input of the key 11 is connected to the output of the relay element 12 with an adjustable deadband. The output of the key 11 is connected to; the input of the control circuit 13, the engine 14 of the pressure screw 6. The motor 14 is connected to the sensor 15 of the speed of movement of the pressure screw 6, which has a burr element 16 at the output, which is connected to the first input of the relay element 12 with an adjustable deadband, the output of which is connected to the second input 17 control signal module. The third and fourth inputs of the relay element 12 with an adjustable deadband are connected to the outputs of the rolling force sensor 9 and the knob 18 of the response threshold of the relay element 12 with an adjustable deadband, respectively. The output of the rolling force sensor 9 is connected to the first input of the adder

5, the second input of which is connected to the output of the reference source 21, the output of the adder 20 is connected to the first input of the multiplication unit 22, the second input of which is connected to the output of the control signal generating unit 1, the output of the multiplication unit 22 is connected to the input of the module 17 and the second the input of the relay element 11.

The device works in the following / way.

By selecting the voltage of the reference source 21, the gain of the regulator is determined based on the conditions of its stability in the absence of rolling pressure. From the output of the position sensor 4 and the sensor 9, the rolling force to the first inputs of the first 2 and second 3 elements of comparisons, respectively, receives signals

5 proportional to the current values of the KOHTpojrapyeMHX rolling parameters, where they are compared with the set values of the sTrfx parameters, received at the second inputs of the first 2 and second 0 3 comparison elements. Signals of deviation of the technical parameters from their predetermined values are fed to the first and second inputs of the control signal generation unit 1, which processes these signals in accordance with the well-known Sims-Golovin method and produces an alternating control signal proportional to the deviation of the thickness of the rolled metal from its 50 specified value. The alternating control signal is fed to the second input of the key 11 and to the input of the V7 unit, where it is converted into a signal equal to the modulus of this signal, i.e. independent of the sign of the control signal, and then fed to the second input of the relay element 12 with an adjustable deadband. At the same time, the fourth and third inputs of the relay element 12 with an adjustable deadband sensor 9 receive a signal proportional to the rolling force, and from the setting device 18, the trigger threshold signal for each stand depends on its characteristics and is set experimentally. In sum, these two signals determine the dead zone of the element 12. They are equal to the minimum value of the control module j signal necessary for starting the engine of the pressure screw of this stand at a given force npoKiaT. The magnitude of the control signal module required to start the pressure screw motor at a given rolling force varies depending on the magnitude of the rolling force. This change occurs by changing the signal level at the input of multiplication unit 22 depending on the level of the rolling force through the scale converter 19 and the adder 20. The dead band, reduced to a half of the strip, remains constant at all rolling forces, which provides increased accuracy rolling. If the control signal module is less than the sum of the signals mentioned above, the relay element 12 with the adjustable dead band, the control signal does not pass through the switch P in the control screw circuit 13 of the pressure screw 6, the motor 14 is de-energized, the pressure screw 6 is fixed and at the output of the sensor 15 the speed of movement and the relay block 16 signals are missing. As soon as the control signal module exceeds the amplitude of the rolling force signals and the trigger threshold, the relay element 12 is turned on, the key 11 is opened and the control signal passes the control circuit, which by means of the motor 14 drives the pressure screw 6 at a speed proportional to the control signal and direction corresponds to the sign of the control signal. At the same time, the signal of the speed sensor 15 at the output of the relay unit 16 appears a constant signal appearing at the first input of the relay element 12 exceeding that. the sum of the rolling force signals and the trigger threshold. Thus, after starting the clamp screw until it is completely stopped, the relay e, switch 12 is turned on and the key 11 is opened to pass the control signal to the control screw of the motor 14 of the pressure screw 6. In other words, after the start of the pressure screw

6, the dead zone in the position control channel becomes equal to zero and is restored only after stopping the pressure screw 6. Thus, in the proposed

automatic adjustment device: ProKa thickness: due to the introduction of additional elements and connections, the adjustment accuracy is increased in comparison with the known technical solutions, as a result of which the variation in the thickness of the rolled product from the specified value is reduced. This {makes it possible to bring the distribution center to the

lower limit of minus tolerance,

which allows to increase the yield of the metal during rolling.

Claims (1)

Invention Formula thirty The device for automatic adjustment of the thickness of rolled on av.st. No. 789174, distinguished by the fact that, in order to increase the control accuracy, it additionally contains a multiplication unit, an adder, a reference source, a large-scale converter, and a large-scale input: the converter is connected to the output of a rolling force sensor, and the output of the reference source is connected respectively to the first and second inputs of the adder, the output of the coupling is connected to the first input of the multiplication unit, the second input of the multiplication unit is connected to the output of the generating unit of the control signal, stroke multiplying block is connected to the input of the modulation control signal and a second input key. Sources of information that are taken into account in the examination 1. The author's certificate of the USSR  789174, CP. 82 B 37/00, 1977.