SU789176A1 - Apparatus for determining billet presence in rolling rolls - Google Patents

Description

one

 The invention relates to metallurgy, and more specifically to rolling i and casting-rolling units.

The invention can most effectively be used in units where it is necessary to determine the presence of a billet in the rolling rollers, for example, to control the system for adjusting the loop (tension) of the billet with pre-rolling rollers.

The closest in technical essence to the present invention is a device for determining the static component of the motor current.

This device contains to-15 ka and engine speed sensors, Hall emf sensor and operational amplifiers, the parameters of which are selected in such a way that provide physical modeling of the dynamics of the engine, and 20 the first operational amplifier, whose input through the capacitor and resistor is connected to the speed sensor, produces solution of the circuit equation consisting of series-connected differentiating and inertial links, providing at the amplifier output a signal corresponding to the dynamic component of the motor current ate The second operational amplifier, the inputs of which are connected to the output of the first amplifier and to the output of the current sensor, produces a summation of the motor current and its dynamic component, with the result that the static component of the motor current 1 is obtained at the output.

The disadvantage of this device is the presence of a differential link, which, as is well known, does not have sufficient accuracy, is susceptible to interference and is laborious in tuning. In this case, the device can not have the necessary reliability. Malfunctions in the operation of the device lead to an increased scrap of prokag and simple equipment when using the device to control the system for controlling the loop (tension) of the workpiece before the mill rolls.

The purpose of the invention is to improve the reliability of determining the presence of the workpiece in the mill rolls, by increasing the noise immunity and increasing its accuracy by switching from differentiation to integration.

Claims (1)

The goal is achieved by the fact that the device for determining the presence of a cut in the rolling rolls, co; , .i -:,. t: motor, current sensors, rotational speeds and motor magnetic flux, further comprises a multiplication unit, an integrator proportional amplifier with a high gain, while the outputs of the current and magnetic flux sensors are connected to the inputs, intelligently The output of which is connected to one of the inputs of the integrator, the code of the latter is connected to one of the hoses of the proportional amplifier, the second input of which is connected to the output of the motor speed sensor, the output of the proportional amplifier is The device is connected to the second input of the integrator. The implementation of the device for determining the presence of metal in the mill rolls ensures its greater noise immunity and accuracy, which, in turn, improves the reliability of the entire rolling mill and reduces its downtime. FIG. 1 shows a block diagram of the device. A device for determining the presence of a billet in the mill rolls consists of mill rolls 1 designed for p, g. rolled billet 2, drive motor 3, in the core of which the current sensor 4 is mounted, a speed sensor 5 is installed on the shaft, a magnetic flux sensor 6 is installed in the excitation winding. The outputs of the current sensor 4 and magnetic flux sensor 6 are connected to the inputs of the multiplication unit 7, the output of which is connected to one of the inputs of the integrator 8, the output of the latter is connected to one of the inputs of the proportional amplifier 9, which has a large gain factor. The second input / proportional amplifier is connected to the output of the rotational speed sensor 5 of the engine 3, and the WELLPROUT proportional amplifier 9, the signal which characterizes the static moment on the shaft, is connected to the second input of the integrator 8. The device works as follows. When the motor rotates 3 rolls 1 at the inputs of the block; 7 multiplications from the current sensor 4 and the magnetic flux sensor 6 receive signals which in multiplication unit 7 are converted into a signal characterizing the instant of the motor 3. This signal from multiplying unit 7 goes to one of the inputs of the integrator 8, to the other input of which the output signal is proportional to the amplifier 9. This signal, which characterizes the static moment on the motor shaft 3, is the output signal of the device and can be used in various automatic control systems. When the engine rotates 3 rolls .1 without billet 2, the motor current signal at the input of multiplication unit 7 characterizes the no-load current, and the output signal of the device hacks the static idling moment. Upon receipt of the workpiece 2 in the rolls 1 static moment of the engine increases and, accordingly, the signal at the output of the device increases. Various changes in motor speed settings and the associated changes in dynamic torque that are unavoidable in rolling units, or when mill rolls are operated with an adjustable loop (tension), do not change the output signal of the device, which changes only when the static oment changes on the engine shaft. The electronic part of the device represents an analog model of the second, engine link, which can be written with the following equations. The equation of the drive dynamics is id: - where M is the motor torque; static moment reduced to the engine shaft; QD - the flywheel torque of the drive, reduced to the motor shaft; VI - engine rotation speed. The voltage at the output of the motor current sensor 4 is equal to and, 14-1, (i) where K -.- is the current-gear ratio of the current sensor; 1 - motor current. The voltage at the output of the sensor 6 of the magnetic flux of the engine is. "3) where Kf is the gear ratio of the magnetic flux sensor of the engine; F - the magnetic flux of the engine. The voltage at the output of block 7 is multiplied by and, - К. Кф1-Ч, Ц) where Kf is a large-scale; coefficient leHT. The voltage at the output of the integrator 8 is equal to V- (r, -Ub): where (J, voltage at the output of the device; constant integration of the integrator (it is assumed that the resistances on the integrator's holders are equal.) The voltage at the output of the device is Jb-- - (Uy-U5). Where K is the gain of the proportional amplifier (it is considered that the impedances at the input of the proportional amplifier are equal.) TJj is the voltage at the output of the speed sensor, which is equal to .05 - Cs Chika speed; M - speed vrsitseni engine Solving equations (1-7) gives Ub /; GD L.i.plp f T;:,) f The analysis of the expres sion (8) shows that with a large coefficient K and the choice of a constant integration of T and the voltage at the output of the device is equal. those. This voltage characterizes the static moment on the motor shaft. Making the device for determining the presence of the workpiece in the rolling rolls by the proposed method allows simple means of determining the presence of the workpiece in the rolling rolls with greater reliability by static moment of the engine by increasing its noise immunity and accuracy. As a result, it becomes possible to eliminate downtime and rejects due to failure of similar devices, such as HHMMccix earlier. Apparatus of the invention for determining the presence of a workpiece in rolling rollers containing a motor, current sensors, rotational speeds and magnetic flux of an engine, characterized in that, in order to increase its operational reliability by increasing accuracy and noise immunity, it further comprises a multiplication unit and an integrator proportional amplifier with a large gain, while the outputs of current sensors and magnetic flux are connected to the inputs of the multiplication unit, the output of which is connected to one of the inputs of the integrat The output of the latter is connected to one of the inputs of the proportional amplifier, the second input of which is connected to the output of the motor speed sensor. The output of the proportional amplifier is the output of the device and is connected to the second input of the integrator. Sources of information, take into account in the examination 1. Slezhanovsky on. DC reversible motor. Metallurgists, 1967. p. 184. u Us KC ":"