SU1519855A2 - Control dy flying shears operating in continuous rotation mode - Google Patents

Abstract

The invention relates to mechanical engineering, in particular to the processing of metals by pressure, and can be used to automate rolling cutting units equipped with a speed-equalizing mechanism. The purpose of the invention is to increase the yield of rolled metal by increasing the accuracy of cutting by fully compensating for the dynamic moment on the drive motor shaft. The device contains a system for setting the average speed of volatile scissors, speed controllers, and current for the driving engine of volatile scissors. The additional introduction of an irreversible counter and a voltage-code converter ensures accurate compensation of the dynamic moment of a flying scissors drive motor by generating an artificial cut sensor signal that anticipates a cut-time sensor signal at a constant time equal to the signal delay time of the drive motor current circuit. . 3 il.

Description

The invention relates to the field of mechanical engineering, in particular to the processing of metals by pressure, can be used to automate rolling cutting units equipped with a speed equalization mechanism and is an improvement of the device according to the author. St. No. 1440627.

The purpose of the invention is to increase the yield of rolled metal by increasing the accuracy of cutting by fully compensating the dynamic moment on the shaft of a drive-driven engine.

FIG. 1 shows the functional :, diagram of the control of flying scissors; figure 2 is a functional diagram of the drive of volatile scissors; on . FIG. 3 is a timing diagram of the formation of a cut sensor signal.

The device contains a drive 1 of flying scissors (LI) 2, articulated with a drive through the speed-equalizing mechanism 3. A tachogenerator 4, a pulse sensor 5 of the engine speed and a sensor are connected to the motor shaft.

: l

;about

eo

U1 SP

1H

6 cuts. With compression 7 P (. 1 medium: your measuring rollers 8 bw charge pulse - Hbrii rolling stock sensor 9. In the digital speed control circuit of the LIE drive, a converter is entered

10 code - frequency (as frequency adjuster), slnn1 with setting frequency

11 lengths, reversible counter 12, the first converter 13 code - voltage, lock} 1outy kol} 1 tour of analog speed control and pulse sensor 5 engine speed,

The analog speed control loop includes a 14 speed controller, a drive of 1 volatile scissors, and a tachogenerator 4, as well as a frequency converter 15 — voltage as an analogue speed reference. The dynamic moment compensation channel comprises the first non-reversible counter 16, the compensation block 17 dynamic moment, the second transducer 18 code voltage, the quad 19 and the multiplication unit 20. The second non-reversible counter 22 and the voltage converter 21 are a code intended to form an artificial cut sensor signal, which always prevents a cut sensor 6 signal for a constant time. Drive 1 of the volatile scissors comprises a drive motor 23, powered by power amplifier 24, and a current drive control loop of the drive motor, including a current regulator on the amplifier 25 and a current sensor 26.

YcTpoficTBo works as follows.

The dimensional cutting of rolled products to specified lengths is carried out by continuous digital adjustment of the angular velocity of the scissors engine in accordance with the expression

Vn lo

v - -

A rh lj

Vn

L

where V is the rental rate; K „, L, - respectively, the radius and perimeter of the drums LN; L is the specified length of cut sheets. The implementation of the relation (1) is carried out in the code-frequency converter 10 by forming at its output a frequency signal specifying the drive speed LF in accordance with the expression

f

- f. .

   L,

(2)

where f. - frequency) signal from the output of the pulse sensor 9, prc. fractional speed strip.

IIpeciGpaaoBaTejib 15 frequency - voltage converts the signal f, to the proportional signal U of the analog speed reference of the drive. Accurately maintaining the speed of the drive Ш1, corresponding to 4acTcjTe fj, is performed by an automatic (J digital control with a reversible counter 12, which compares the reference frequency fj and feedback fts from the pulse sensor 5 of the engine speed. The converter. 13 converts the output code of the counter 12 Analog signal UU, which continuously compensates for the accuracy of the analog motor speed control loop. The speed equalization mechanism 3 converts the uniform rotation of the motor shaft into an uneven rotation. LN s drums so that, while maintaining an average speed over the period, to provide at the time of cutting blades equal linear velocity and shear rolled .Velichina eccentricity aligning mechanism 3 is set velocity as a function of the length of the cut according sootnoscheniyu

(; E

  g L + L;

(3)

where, E - relative and absolute eccentricities respectively

g is the radius of the cranks of the speed equalization mechanism.

The uneven rotation of the shaft of the LN drums inside each revolution causes the appearance of dynamic moments on the shaft of the drive motor, which causes fluctuations in the speed of the shaft of the drive motor, negatively affecting the accuracy of rolling. The specified dynamic torque depends on the set eccentricity (i.e., on the specified strip length) and is a function of the angle of rotation of the drive shaft

M

 J, w.F (L ,,,),

(four)

the moment of inertia of the drums LN; relative rt is the dynamic moment at a unit angular velocity of the drive shaft and at a unit moment of inertia of the drums LN.

j-5 and filing mechanism

IIo3 ruNfy To eliminate the effect of the specified torque on the speed of the drive motor, it is compensated by forming (.) A van in the dynamic current signal cutting cycle U its Tia second input through equalizing the speed of the drive current regulator 25) volatile scissors. The indicated signal peals the principle of invariance, carried out the adjustment by feedback, and the disturbance signal is generated by simulating its mathematical expression (4). For this purpose, in the first non-reversible counter 16, since the next impulse of the artificial cut sensor (IDR) appeared by counting pulses frequency f is formed by the code of the angle SL of the rotation of the propulsion engine. In block 17, the dynamic compensation code N is generated using the t / and L- codes. The dynamic moment compensation unit 17 is made on the basis of a programmable memory element, each memory page of which is determined by an LI code, the cell address in a page frame is determined by the oL code, and the contents of each memory cell is the N code. The relative rto of the dynamic moment F (Ljoi), corresponding to the value of the current angle of rotation of the motor shaft

multiplied by the signal from the quadra output

specified cutting length. The code N of the converter 18 is converted into an emu proportional voltage U. forming a dynamic current in accordance with the expression (4).

The artificial cut sensor (IDR) signal, which anticipates at any rate the strip feeds the cut sensor signal (DF) for a constant time equal to the signal delay time in the current control loop, is formed using a non-reversible counter 22 and a converter 21 according to the time diagram on fig.Z. By the signal ДР on the sensor 6 of the cut, the second non-reversible counter 22 from the voltage converter 21 - the code is entered into the Np code of the initial installation of the counter. Next, the counter 22 is filled with frequency pulses f p coming from the sensor.

55

5 speed; | wigatel, and when it overflows, the IDR signal is generated. As can be seen from the timing diagram in FIG. 3, the lead time of a TG pulse IDR with respect to the DS pulse is

N

CJ.

- N,

(five)

where t

and,

stsodnogo turnover knife-22.

- time prostrate;

counter h

As with astatic speed control, the frequency of the assignment and feedback is equal to

f,

f L2.

n t Li

(6)

25

20

AND CODE N is proportional to the speed of hire

25

thirty

Choosing counter volume 22

 sch

LC

with

(9)

where L is the discreteness of the measurement of movement in the device, and taking into account that

fp.oC

(10) expression (8) can be reduced to

0

Ll

Vn

 TO

oC

pchm

TO

PNK

Va Lo (11).

+ K

PMN

TO

peak

From (11) it can be seen that the lead time L of the IDD pulse with respect to the DS pulse is by a given value independent of the speed of the rolled steel. In this case, the frequency converter ratio — voltage 15 and voltage — code 21 is chosen such that the value t corresponds to the signal delay time in the current control loop.

Thus, the invention makes it possible to improve the cutting accuracy at rolling feed rates lower than the maximum by accurately compensating the dynamic moment by compensating a signal with: control always corresponding to the delay time of this signal in the current control circuit of the flying scissors drive motor.

F o

rmula of invention

Control unit for flying scissors operating in continuous rotation mode by aut. St. No. 14А0627, 0 tl and h and so that, in order to increase the yield of rolled metal by increasing the accuracy

g) cutting due to full compensation of the dynamic (; ms) cop on the drive motor shaft, additionally introducing) a second non-reversible counter and a voltage transducer - a code whose input is connected to the output of the frequency converter - voltage and the output to the second input of the non-reversing counter, the counting input connected to the output of the pulse motor speed sensor, the recording input to the cut sensor, and the output to the reset input of the non-reversible counter.

. &

Claims (1)

Claim Control device for flying shears operating in continuous rotation mode according to ed. St. No. 1440627, it is noteworthy that, in order to increase the yield of rolled products by increasing the accuracy of cutting due to the full compensation of the dynamic moment on the shaft of the drive motor, an additional 5 second non-reversible counter and voltage converter are introduced - code input connected to the inverter output frequency - voltage, and output - with an installation inlet of a second 10 ^not ₽ '' ^ve P ^Siv Nogo counter counting input connected to the output impulse engine speed sensor, an input write - to cut sensor, and output - to in ode irreversibly reset counter. I 519855