SU1632536A1 - Metal sensor in double-strand stand - Google Patents

Abstract

The invention relates to rolling production, in particular to control and regulating devices of rolling mills, and can be. used in the systems of automation and control of the metal rolling process in the two-filar rolling stand. The purpose of the invention is to increase the reliability of the sensor due to the elimination of false slaves. The sensor contains a 1-meter current meter for a rolling mill motor core, a first two-threshold comparator 2, a low-pass filter 3, a multiplier 4, a single-threshold comparator 5, a second two-threshold comparator 6, a counter 7, a circuit AND 8, a pulse generator 9, a trigger 10, two circuits OR 11 and 12, two pulse drivers 13 and 14 and a delay line 15. When the rollers pick up the double-strand rolling stand of one billet, logical 1 appears at the output of the two-threshold comparator 2 and logical O is stored at the output of the two-threshold comparator 6. After the rollers capture one of the billet at the input of the two-threshold comparator 6 with the help of a multiplier 4 and one threshold comparator 5 a reference voltage level is recorded, which eliminates the effect of current fluctuations in the core of the rolling motor caused by a change in the rolling mode. With the capture of the second workpiece, logical 1 appears at the output of the two-threshold comparator 6. Logic O at the outputs of the two-threshold comparators indicate the absence of workpieces in the cage. 1 il. (L 05 from 8 g

Description

316

The invention relates to rolling production, in particular, to control and regulate the devices of rolling mills, and can be used in automation systems and control of the metal rolling process in a two-wire rolling stand.

The purpose of the invention is to improve the reliability of the sensor for the presence of metal in a double-strand rolling stand by eliminating false positives.

The drawing shows the block diagram of the sensor.

The sensor for the presence of metal in a double-roll rolling stand contains a meter 1 of the current of the engine of the rolling stand, the first two-threshold comparator 2, the low-frequency Liltr 3,

In the initial state (in the absence of blanks in the rolls of the stand), the output signal of the meter 1 of the current of the motor of the rolling stand is close to zero, since the engine runs almost idling. For each of the two threshold comparators 2 and 6, two threshold levels are applied: for comparator 2 and for comparator 6, moreover

multiplier 4, single-threshold compara- 20, a. On single threshold

the torus 5, the second two-threshold comparator 6, the pulse counter 7, the AND 8 circuit, the pulse generator 9, the trigger 10, the OR 11 and 12 circuits, the pulse former 13 and 14, and the delay line 15. 25

The output of the current meter 1 of the engine core of the rolling stand is connected to the input of the first two-threshold comparator 2 and through a low-frequency

comparator 5 supplies threshold voltage which is less than 1) 6d (sources of threshold voltages are not shown). The output signals of all comparators are equal to zero, except for a single signal (logical 1) at the first inverse of the comparator 2. This signal through the OR 11 circuit is fed to the first input (the input set by the parameter 5 serves a threshold voltage less than 1) 6d (threshold sources stresses are not shown). The output signals of all comparators are zero, except for a single signal (logical 1) at the first inverse of the comparator 2. This signal through the OR 11 circuit goes to the first input (input set filter 3 with the first input of the multiplier 4.30 KI to zero) of counter 7, zeroed him

exits.

The generator 9 pulses sprinkles pulses at the first input of the circuit And 8, but

the second input of which is connected to the output of the counter of 7 pulses, and the output to the inputs of single-threshold 5 and two-threshold 6 comparators.

The first output of the first two-threshold 5, the absence of a permitting signal on the first comparator 2 is connected to its first second input, which does not allow the pulse input of the first OR circuit. It, and then pass to the first (information output - through the delay line 15) input of the counter 7. with the second input of the second circuit OR 12, the signal at the output of the low-frequency output of the second two-threshold compara- tor filter 3 is a smoothed signal torus 6 through the second driver 14 scrap from the output of the meter 1 of the current of the pulse core is connected to the second motor inlet of the rolling stand and is close to zero in the level of the first OR circuit 11 and the first input. The signals at the inputs and the second circuit OR 12. The output of the single-output outputs of the remaining blocks of the sensor of the comparator 5 through the first form-45 litchi metal in the double-thread distributor 13 pulses connected to the back stand are zero, the first trigger input 10, the second Sensor is ready To fix the moments, the input of which is connected to the output of the secondary gripping and ejection of the workpieces by the swarm rolls of the circuit OR 12, the generator output 9 t of the double-stretch rolling mill stand, the pulses are connected to the first input, “With the capture of the first workpiece, - rolling my one of the threads is rolls with a trigger output 10, and the rolling mill output, the current of the rolling mill circuit 8 is connected to the first (informational) input of the pulse counter 7, the second input of which (the pulse counter input to the zero) is connected to the output of the first the circuit OR 11. The second (direct) output of the first two-threshold comparator 2 and the output of the second two

A motor (not shown) increases dramatically. The meter 1 of the current of the motor of the rolling stand produces a signal proportional to the current of the mill electric motor, while the output voltage of the meter 1 also increases.

the threshold comparator 6 are the outputs of the sensor for the presence of metal in a double-strand rolling stand, respectively, in the first and second yarns.

The sensor works as follows.

The operator applies a supply voltage to the device (power source is not shown).

In the initial state (in the absence of blanks in the rolls of the stand), the output signal of the meter 1 of the current of the motor of the rolling stand is close to zero, since the engine runs at almost idle speed. Two threshold voltage levels are applied to each of the two threshold comparators 2 and 6: a comparator 2 and a comparator 6, and

 , a. On single threshold

 , a. On single threshold

comparator 5 supplies threshold voltage which is less than 1) 6d (sources of threshold voltages are not shown). The output signals of all the comparators are zero, except for a single signal (logical 1) at the first inverse of the comparator 2. This signal through the OR 11 circuit goes to the first input (installation input to zero) of the counter 7, wrapped it

exits.

The generator 9 pulses sprinkles pulses at the first input of the circuit And 8, but

, 5 the absence of an enable signal at its second input prevents pulses from passing to the first (informational) input of counter 7. The output signal of the low-frequency filter 3 is a smoothed signal from the output of meter 1 of the current core of the rolling mill motor and the level is close to zero. The signals at the inputs and outputs of the remaining sensor blocks of the metal in a double-strand rolling stand are zero, the sensor is ready for fixing the moments of capture and ejection of the blanks with rolls t of the double-strand rolling stand,, “When the first workpiece is rolled along one of the thread rolls rolling stand, the current core rolling

five

A motor (not shown) increases dramatically. The meter 1 of the current of the motor of the rolling stand produces a signal proportional to the current of the mill electric motor, while the output voltage of the meter 1 also increases.

The signal from the output of meter 1 is fed to the input of the first two-threshold comparator 2 and, smoothed in the low-pass filter 3, to the first input of the multiplier 4. At the moment when the voltage at the input of the first two-threshold comparator 2 becomes equal to the higher threshold voltage U of this comparator, it switches, and at its first (forward) output a logical 1 (single signal) appears, indicating that the rolls have gripped the first workpiece. In this case, a single signal disappears from the first (inverse) output of the comparator 2 and, accordingly, the zero signal from the first input (input to zero) of counter 7 is removed. Counter 7 is ready for recording, its outputs are zeroed and, therefore, at the second input of multiplier 4 - a zero signal, therefore at the output it is also a zero signal, despite the presence of a signal at its first input.

A single signal from the second (direct) output of the comparator 2 enters the input of the delay line 15 and after a time of about 0.1 s, an output appears at the output of this delay line 15, passing through the second circuit} SHI 12 to the second trigger input 10 and switching it to a single state. A single signal from the output of the trigger 10 is fed to the second input of the AND 8 circuit, allowing the pulses from the output of the generator 9 to the first (informational) input of the counter 7. Counter 7 begins to read these incoming pulses and a binary code signal appears at its output the second input of multiplier 4, at the first input of which there is a signal from the output of the low-pass filter 3. At the output of multiplier 4 and, respectively, at the inputs of comparators 5 and 6, a signal appears that increases as the signal increases in binary code at the output of sensor 7. At that moment, when the voltage at the inputs of comparators 5 and 6 reaches the reference level specified by the threshold voltage of the single-threshold comparator 5, the latter switches, and a single signal appears at its output passing to the input of the first imager of 13 pulses, which on the front of this signal generates a pulse arriving at the first input of the trigger 10,

five

0

0

switching it to the zero state. Disconnected, the signal at the second input of the circuit And 8 disappears, and the flow of pulses to the input of the counter 7 stops and, accordingly, their counting. At the output of the counter 7 and at the second input of the multiplier 4, a binary code is recorded, corresponding to the reference voltage level at the inputs of comparators 5 and 6, from which the voltage rises will be counted when the roll stand is seized by the second billet.

Thus, the voltage at the inputs of the comparators 5 and 6 is maintained at the same level when rolling any single billet, regardless of the rolling mode of this billet.

After fixing the reference voltage at the inputs of the comparators 5 and 6, the sensor is ready to register the capture of the second billet rolled along

5 another rolling line of this rolling stand.

According to the production technology of rolled products on a double-thread mill, the blanks are fed into the cage sequentially, while observing the specified shutter speed between feeding the blanks one by one and the other, therefore the introduction of delay line 15 does not impair the reliability of the sensor.

When chahvaty rolls of the stand of the second billet current core of the rolling motor still increases, the output signal of the meter 1 current core increases, which leads to an increase in the signal at the output of the low-pass filter 3 and, accordingly, at the output of the multiplier 4. The signal at the inputs of the Comparators 5 and 6 increases, and at. the moment he reaches the level

5 of the higher threshold voltage Ugg, the comparator 6 switches, a single signal appears at its output, indicating that the second billet is seized by the rolls of the rolling stand.

0 At the same time, at the second (direct) output of the comparator 2, a single signal is saved until the first of the blanks is ejected by the rolls of the double-thread stand.

A single signal from the output of the comparator 6 is fed to the input of the imaging device 14 pulses, the output of which retains the zero signal, since it generates pulses from the cut of the 4-signal at its input.

five

0

When one of the blanks is ejected from the stand rolls, the current of the rolling motor decreases, the voltage at the inputs of the comparators 2.5 and 6 decreases, and at the moment when it becomes equal to the smaller threshold voltage 116 dd of the comparator 6, it switches Logic O, indicating the release of one of the blanks from the rolls of the double-strand rolling stand. The second pulse shaper 14 generates a pulse by transmitting a signal at the output of the second two-threshold comparator 6, and this pulse passes through the OR 11 circuit to the second input (the setup input to zero) of the counter 7, swatted its outputs, and through the OR 12 circuit to the second trigger input 10, switching it to a single state. From the output of the trigger 10, a single signal arrives at the second input of the And 8 circuit, allowing passage of pulses from the generator output 9 pulses to the first (informational) input of counter 7. At the end of the pulse from the output of the second driver 14 pulses the signal at the second input (input setting to zero) counter 7 disappears and counter 7 starts counting pulses arriving at its first (informational) input. At the output of counter 7, an increasing signal appears in the binary code arriving at the second input of multiplier 4, at the first input of which there is a signal, since there is one blank in the rolls of the stand. The magnitude of the signal at the output of the multiplier 4, equal to zero before this, due to the zero output of the counter 7, begins to increase with an increase in the signal in the binary code at the output of the counter 7. At the moment when the voltage at the inputs, the Comparators 6 and 5 reach the level The threshold level, given by the threshold voltage Uj of the comparator 5, is switched, and at its output there appears a single signal passing to the input of the first pulse generator 13, which generates a pulse on the front of this signal. This pulse arrives at the first input of the trigger 10, switching it to the zero state. The permissive signal at the second input of the AND 8 circuit disappears and the arrival of pulses at the input of counter 7 and their counting stops. Similar to that described at the output of counter 7 and

The second input of the multiplier 4 fixes the signal corresponding to the reference voltage level, which is set at this output of the multiplier 4 and the inputs of the comparators 5 and 6. The sensor is again ready to register the capture of the second workpiece.

With the capture of the rolls of the cage of the second workpiece sensor works similarly.

If, before the second billet is seized by the rollers of the stand, the first is ejected, the current of the rolling motor crust decreases to almost zero, the voltage at the inputs of the comparators 2.5 and 6 decreases even at the moment when it becomes equal to the lower threshold voltage UJLM comparator 2, it switches. At its second (forward) output, a logical O appears, indicating the ejection of the first billet from the rolls of the double-thread rolling mill, and its first (inverse) output appears logical 1. This single signal is fed through the OR 11 circuit to the setup input counter 7 to zero and zero it until its output is captured by the rollers of the stand

With the capture or release of blanks sensor continues to work as described.

Thus, the capture by the rolls of the stand of one billet leads to the appearance of logical 1 at the second (direct) output of the first two-threshold comparator 2 and preservation of logical O at the output of the two-threshold comparator 6.

The seizure of the second billet by the rolls leads to the appearance of logical 1 as well at the output of the two-threshold comparator 6. Logic O at the second (direct) output of the comparator 2 and the output of the comparator 6 indicate the absence of billets in the cage.

The proposed sensor for the presence of metal in a double-strand rolling stand is more reliable in operation due to the elimination of false positives.

Claims (1)

Invention Formula A metal presence sensor in a double-thread rolling stand containing a current meter of a rolling mill motor, a pulse counter, two pulse shapers, and a single-threshold comparator, the exhaust of which is connected to the input of the first pulse shaper, in order to increase reliability by eliminating false alarms , it is equipped with a low-pass filter, two double-threshold comparators, a multiplier, a pulse generator, an AND circuit, two NLI trigger schemes and a delay line, and measure the output A current of the motor box of the rolling stand is connected to the input of the first two-threshold comparator and through a low-pass filter to the first input of the multiplier, the second input of which is connected to the output of the pulse counter, and the output to the inputs of the single-threshold and second two-threshold comparator, the first output of the first the two-threshold comparator is connected to the first input of the first OR circuit, and the second output via the delay line to the second input of the second OR circuit, the output of the second two-threshold comparator is connected to the second input of the first OR circuit and the first input of the second OR circuit, the output of which is connected to the second trigger input, the first input of which is connected to the output of the first pulse generator, the output of the pulse generator is connected to the first input of the circuit I, the second input of which is connected to the output of the trigger, and the output of the circuit s and connected to a first input of a pulse counter, a second input coupled to an output of the first OR circuit.