JPS6027461A - Method and device for controlling casting mold vibrator - Google Patents

Abstract

PURPOSE:To excite a casting mold in a high frequency region without changing the transmission function of a control system by correcting the amplitude of the mold in such a way that the set amplitude value increases apparently when said amplitude is smaller than the set amplitude value of a function generator. CONSTITUTION:The amplitude 1.5mm. of a cylinder 18 is detected by an amplitude detector 31 and is inputted as the signal corresponding to 1.5mm. amplitude to a summing point 33. Said signal is added to the set amplitude signal of 3mm. inputted from an amplitude setter 12 at the point 33 and the signal corresponding to 3-1.5=1.5mm. is outputted from the point 33. This signal is amplified with an amplifier 34 and if an amplification factor K is made ''1'', the signal corresponding to 1.5mm. is outputted from the amplifier 34 to a summing point 35. The signal corresponding to 1.5mm. from the amplifier 34 and the set amplitude signal of 3mm. from the setter 12 are added at the point 35 and the signal for 1.5+3=4.5mm. is outputted to a function generator 13. The amplitude of the cylinder 18 is increased up to 3mm. in accordance with the case in which the set amplitude signal inputted to the generator 13 is increased from 3mm. to 4.5mm. in this state.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention vibrates the vibration system of the beam supporting the mold using an electro-hydraulic servo device when continuously casting slabs in a mold to ensure defect-free casting. The present invention relates to a method of controlling a mold vibration device for obtaining slabs and a control device thereof.

(Prior Art) In the continuous casting method, it is necessary to reduce the friction between the slab and the mold to prevent seizure of the slab or breakout accidents. Therefore, in order to reduce the friction between the mold and the slab, continuous casting is carried out using the so-called mold vibration method, in which casting is performed while the mold is vibrated up and down.

In continuous casting equipment using a mold vibration method, for example, as shown in FIGS. 1 and 2, a mold 4 is supported by a vibrating beam 2 together with a water supply claim 5 provided on the outer periphery of the lower part thereof, and the vibrating beam 2 is fixed. One end of one side is rotatably supported on the pedestal 7 by a vibration fulcrum 6, while one end of the other side is connected to the excitation cylinder 1 of an electric oil field servo device 8 provided on the base of the pedestal 7. By the operation of the vibration cylinder 1, the vibration system of the vibration beam 2 including the mold 4 is vibrated with respect to the pedestal 7 about the fulcrum 6 via the vibration guide 3.

By the way, continuous casting using the mold vibration method as described above was driven by a control device as shown in FIG.

In FIG. 3, 11 is a frequency setter, 12 is an amplitude setter, 13 is a function generator, 14 is a control amplifier, and 15 is a servo amplifier, which outputs from a differential transformer 17. The position signal of the cylinder 18 of the electro-hydraulic servo system M8 is amplified by an amplifier 19, and at a summing point 20 the deviation between the output of the function generator 13 and the output of the amplifier 19 is detected. This deviation is amplified by the control amplifier 11 and the output from the servo valve 16, which has an output from the differential transformer 21.
The deviation from the output of the amplifier 22 which increases the position signal of the spool is detected at the summing point 23, this deviation is input to the servo amplifier 15, and the servo valve 16 is input to the function generator 1.
The cylinder 18 is driven according to the above output of the vibrating beam 2.
The mold 4 is vibrated by vibrating the mold 4.

Generally, in continuous casting equipment using the mold vibration method as described above, it is known that increasing the vibration frequency of the mold 4 reduces the incidence of oscillation defects. When the frequency of the output of the transducer 13 is increased from around 1 Hz to about 30 Hz, the amplitude of the vibrating beam 2 will change due to resonance at around 15 Hz, where the above frequency matches the natural frequency of the vibration system of the vibrating beam 2. The amplitude became abnormally large, and thereafter the amplitude attenuated, and it was not possible to obtain a specified amplitude value in a high frequency region around 30 hertz. Furthermore, when the gain of the control amplifier 14 and the servo amplifier 15 is changed in order to correct the above-mentioned attenuation of the vibration 11 of the vibrating beam 2, the stability conditions of the control system change and the control system diverges. There was fear.

(Object of the Invention) The present invention has been made in view of the above circumstances, and its object is to provide a control method for a mold vibration device that vibrates a mold using an excitation signal output from a function generator. If the amplitude of the mold is smaller than the set value of the generator amplitude, the appearance is good, but by correcting the frequency setting device to make it larger, high vibration can be generated without changing the transfer function of the control system. The objective is to obtain a method of vibrating a mold with a sufficient amplitude in several regions.

Another object of the present invention is to convert a position signal of a cylinder that vibrates a mold into an amplitude signal in a control device for a mold vibration device that vibrates a mold using an excitation signal output from a function generator. The transfer function of the control system is changed by providing an amplitude detector and correcting the amplitude setting value of the function generator so that the amplitude of the mold output from the amplitude detector matches the setting value. The object of the present invention is to obtain a stable control device for a mold vibrating device that vibrates a mold with a sufficient amplitude in a high frequency range.

(Structure of the Invention) To summarize the present invention, an electro-hydraulic servo device is driven in accordance with an excitation signal having a preset amplitude and a preset frequency outputted from a function generator, and the electro-hydraulic servo device is driven. A control method for a mold vibration device in which a mold supported by a beam connected to a cylinder of a hydraulic servo device is vibrated, converts the position signal of the cylinder into an amplitude signal, and converts the position signal of the cylinder into an amplitude signal. The deviation from the above-mentioned setting device 1] is calculated, this deviation is multiplied by a coefficient and added to the above-mentioned setting amplitude, and the above-mentioned mold is excited using the output as a new setting amplitude of the function generator. A control method for a mold vibration device is characterized in that:

Another feature of the present invention is that the electro-hydraulic servo device is driven in response to an excitation signal having a set amplitude and a set frequency that are arbitrarily set in advance and outputted from a function generator. A mold vibrating device configured to vibrate a mold supported by a beam coupled to a cylinder, comprising: an amplitude detector for converting a position signal of the cylinder into an amplitude signal; It is characterized by being equipped with a deviation detector that calculates the deviation from the amplitude, and an adder that multiplies this deviation by a coefficient, adds it to the set amplitude, and outputs the result as a new set amplitude signal of the function generator. This is a control device for a mold vibration device.

(Example) Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

A block diagram of a control device for a mold vibration device according to the present invention is shown in FIG.

In the block diagram of FIG. 4, blocks corresponding to those in FIG. 3 are denoted by the same reference numerals, and a description of the blocks will be omitted to avoid duplication.

In FIG. 4, 31 is an amplitude detector, 32 is an amplifier, and 3
3 is a replenishment point, 34 is an amplification device, and 35 is a replenishment point.

The amplitude detector 31 is a circuit that converts the position signal of the cylinder 18 into an amplitude signal of the cylinder 18 from the signal input from the amplifier 19, and this amplitude signal is amplified by the amplifier 32. After that, it is input to the repayment point 33.

The replenishment point 33 is a deviation detector that detects the deviation f between the set amplitude input from the amplitude setting device 12 and the amplitude signal of the cylinder 18 amplified by the amplification device 32. The above deviation ε
is input into an increase width-34 with a constant increase 11] rate K;
The amplifier 34 outputs a signal of ε.

The above signal, ε, and the setting amplitude signal output from the amplitude setting device 12 are added at a replenishment point 35 constituted by an adder, and the appearance of this replenishment point 35 determines the new setting amplitude. It is output to the function generator 13 as a width signal.

In the conventional control device shown in FIG. 3, when the setting amplitude signal for vibrating the cylinder 18 with an amplitude of 3 mm is output from the amplitude setting device 12, the cylinder 18 is, for example, If it only vibrates with a width of .5 degrees,
In the control device of FIG. 4, the cylinder 18
can be vibrated with a 3M amplitude.

That is, in the control device of FIG.
The amplitude of the vibration +1] 1.5 mm is detected by the vibration amplitude 1] detector 31, and the detected value is input to the amplifier 32 and added as a signal corresponding to the vibration width of 1.5 mm. It is input at point 33. This addition point 33 is added to the set amplitude signal of 3 mm input from the amplitude setting device 12, and from the addition point 33, it corresponds to (3-1, 5) = 1.5 mm. A signal is output. This signal is amplified by the amplifier 34, and if the increase rate is 1 (=1), a signal corresponding to 1.5 mH is output from the amplifier 34 at the addition point 35. Output to.

At the addition point 35, the signal corresponding to 15 mm from the amplifier 34 and the set amplitude signal of 3 mm from the amplitude setter 12 are added, and (1,5+3) -4,5a
A new set amplitude signal of m is output to the function generator 13.

In this state, in the control device of FIG. 3, the setting amplitude signal input to the function generator 13 is changed from 3 mm to 4.5' m.
Corresponding to the case where the swing width of the cylinder 18 is increased to 3 m.
It can be increased up to mm.

In this case, the transfer function of the control system after the function generator 13 does not change at all, and therefore the stability also does not change.

Furthermore, when the amplitude of the cylinder 18 is 3 mm and is equal to the setting amplitude signal output from the amplitude setting device 12, the deviation ε between the two
becomes ε=0, and the adder 35 inputs the set amplitude signal outputted from the amplitude setter 12 directly to the function generator 13, and the amplitude of the cylinder 18 is input to the function generator 13. It vibrates according to the input setting amplitude signal.

As described above, by controlling the setting amplitude signal input to the function generator 13 according to the amplitude of the vibration of the cylinder 18, the vibration can be controlled without changing the transfer function of the vibration control system of the cylinder 18. The cylinder 18 can be vibrated by the width set by the width setting device 12.

In addition, in the above embodiment, the increaser f1] of the adder 11]
The rate may be selected to match the swing width set by the swing setting device 12.

Next, another embodiment of the present invention is shown in Fig. f55.

In the embodiment shown in FIG. 5, in the control device shown in FIG. 4, the setting device +1J outputted from the amplitude setting device 12 is corrected by digital signal processing, and 41 is the amplitude setting device 18 of the cylinder 18. A to detect as a digital signal
/D converter, 42 is a microcomputer, 43 generates a vibration waveform signal of the cylinder 18 according to the digital signal output from the microcomputer 42;
It is a converter.

For example, the microcomputer 42 repeats steps 10'l to 107 of the length indication flowchart shown in FIG.
D so as to match the set amplitude signal S output from 2.
/ Controls the amplitude of the vibration waveform signal output from the A converter 43.

By doing the above, the microcomputer 42 can
5, and if A=S, output S as it is\new setter rll as one word, and
-S, Iζε+S is output as a new setting amplitude signal, and the vibration amplitude d] of the cylinder 18 can always be made to match the setting amplitude of the amplitude setting device 12.

(Effects of the Invention) As is clear from the detailed description above, the present invention has the following effects:
In the control system of the mold vibration device, if the mold vibration vibration 11] is smaller than the set value, the control system corrects the vibration so that the vibration frequency setting device is larger than the set value. The transfer function does not change (even in the high frequency region around 30 Hz, the mold can be vibrated with a sufficiently large amplitude by a stable control system.

Furthermore, according to the present invention, by simply adding a relatively simple device to the outside of the conventional # type control system, the mold can be stably vibrated with a sufficiently large vibration 1 at high vibration frequencies. A control device for a mold vibration device can be obtained.

[Brief explanation of drawings]

1 and 2 are a side sectional view and a plan view, respectively, showing a part of a continuous casting device, and FIG. 3 is a conventional mold vibration device. The example block diagram, FIG. 6, is a flowchart showing the operation of the microcomputer used in the embodiment of FIG. 4...Mold, 8...Electro-hydraulic servo device, 11.
...Frequency setting device, 12... Width setting device, 13...
Function generator, 18... Cylinder, 31... Amplitude detector, 33, 34... Addition point, 41... A/D
M transformer, 42...Microcomputer, 43...
D/A converter. Patent applicant Kobe Steel, Ltd.

Claims (2)

[Claims] (1) An electro-hydraulic servo device is driven in response to an excitation signal having a set amplitude and a set frequency that are arbitrarily set in advance and output from a function generator, and is coupled to a cylinder of the electro-hydraulic servo device. A method of controlling a mold vibrating device in which a mold supported by a beam is vibrated, converts the cylinder position signal into an amplitude signal, and calculates the deviation between this amplitude signal and the set vibration l]. control of a mold vibrating device, characterized in that the deviation is multiplied by a coefficient and added to the set amplitude, and the output is used as a new set amplitude of a function generator to vibrate the mold. Method. (2) An electro-hydraulic servo device is driven in response to an excitation signal having a preset amplitude and a preset frequency outputted from a function generator, and is coupled to the cylinder of the electro-hydraulic servo device. A mold vibrating device in which a mold supported by a beam is vibrated includes an amplitude detector that converts the position signal of the cylinder into an amplitude signal, and a deviation between the amplitude signal and the set amplitude. An @-type vibration device comprising: a deviation detector for calculation; and an adder for multiplying this deviation by a coefficient and adding it to the set amplitude, and outputting the result as a new set amplitude signal for a function generator. control device.