JPH0639532A - Device for controlling tilting furnace - Google Patents

Abstract

PURPOSE:To precisely regulate discharging quantity of molten metal by calculating the necessary tilting angle from the setting value and the actual measured value of molten metal quantity to be discharged from a tilting furnace and executing feedback control. CONSTITUTION:In the tilting furnace 1, an angle sensor 14 for detecting horizontal level of the molten metal and a control motor 8 for tilt-driving the furnace body are provided. The molten metal in a storing ladle 16 is supplied into a mold 20 on a turn table after measuring with a wt. detecting sensor 24 for weighing ladle 21. The molten metal quantity to be fed into the mold 20 is set and displayed with a setting device 27, and to the molten metal wt. to be fed at the fixed cycle from the tilting furnace 1, a wt. sensor 19 for the storing ladle 16 and the wt. detecting sensor 24 for the weighing ladle are controlled to the aimed setting value by driving the lifting devices 18, 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tilting furnace control device suitably used in a line for continuously producing a copper ingot used as an anode for electrolytic refining from molten metal.

[0002]

2. Description of the Related Art As a conventional technique of the control device for the tilting furnace, for example, there is one disclosed in Japanese Patent Publication No. 61-47627. In this device, the tilt angle according to the required discharge amount is calculated from the tilt angle of the tilting furnace and the theoretical value of the discharge amount at the angle, and the tilt angle is realized in order to realize this tilt angle. The motor as the tilt drive means is feedback-controlled by the detection data about the rotation angle,
The feedback signal is corrected by the detection data regarding the amount of the molten metal actually stored in the pan for receiving the molten metal discharged from the tilting furnace.

[0003]

However, in spite of the above correction, it was difficult to perfectly match the discharge amount of the molten metal with the set value. That is, a. Since there is a certain amount of molten metal in the molten metal path between the tilting furnace and the ladle, there is a time lag between the change in tilt angle and the change in the amount of liquid in the ladle. Inevitable. B. Due to variations in the viscosity of the molten metal, the relationship between tilt angle and discharge is not constant. C. The flow rate of molten metal changes instantaneously due to temporary clogging of the tilting furnace or the outlet of the pan. Due to factors such as the above, it is unavoidable that the control becomes over-controlled or under-controlled. The present invention has been made in view of the above circumstances, and it is an object of the present invention to correct feedback control of a tilt angle to accurately regulate the discharge amount of molten metal.

[0004]

In order to achieve the above-mentioned object, the invention according to claim 1 of the present application is such that the tilting furnace containing the molten metal is tilted by the driving means to tilt the molten metal. In the tilting furnace control device for continuously discharging the tilting furnace from the ladle, an angle sensor for detecting an angle of the tilting furnace, and a molten metal contained in the ladle. And a control means for controlling the drive means by the detection signals of the angle sensor and the liquid quantity sensor, the control means discharging the angle detection signal and the tilting furnace. Calculation means for calculating the tilt angle from the set value of the liquid volume and the discharge amount of the tilting furnace calculated from the detection signal of the liquid quantity sensor, and the driving means of the driving means according to the angle calculated by the calculation means. Control the speed And a tilting speed control means. According to a second aspect of the invention, in the first aspect of the invention, the comparison means for comparing the detection signal for the liquid amount with a reference value, and the control by the tilting speed control means are invalidated by the comparison result of the comparison means. And stop control means for controlling the drive means to start or stop the tilting. According to a third aspect of the present invention, in the first aspect of the present invention, a comparison means for comparing the detection signal of the liquid amount with a reference value, and the calculation means by controlling the calculation means by the comparison result of the comparison means, The calculation control means for changing the number is provided.

[0005]

According to the structure of the invention described in the first aspect, the required tilt angle is calculated from the set value of the liquid amount to be discharged from the tilting furnace and the actual measured value, and the tilt angle is calculated to the calculated tilt angle. A control signal is output to match the actual measured value of the angle. According to the configuration of the invention described in the second aspect, the characteristic of the liquid in the tilting furnace or the shape change of the tilting furnace is changed by invalidating the control of the normal tilting angle by the actual measurement value of the liquid amount. It is possible to correct the error that occurs in the tilt angle calculation due to the above factors. Third
According to the invention described in the section (1), the error can be corrected as in the case of the second section by correcting the calculation formula of the tilt angle according to the actual measured value of the liquid amount.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the overall configuration of the control device of the present invention. Reference numeral 1 is a tilting furnace, and this tilting furnace 1 is
It is supported by the support roller 2 so that it can be tilted (rotated within a certain range in a plane). Further, a gear 3 is provided on a part of the outer periphery of the tilting furnace 1, and the gear 4 meshing with the gear 3 is driven to tilt, so that the molten metal (which is a molten metal) inside is discharged. 5 can be discharged. A posture changing motor 7 and a tilt control motor 8 are connected to the shaft 6 of the gear 4 via speed reducers 9 and 10, respectively, and further, the posture changing motor 7
A clutch 11 is provided between the tilt control motor 8 and the tilt control motor 8. The posture changing motor 7 is used in the tilting furnace 1
When changing the posture significantly (for example, when trying to make a large tilt angle to empty the furnace, or when trying to return from the maximum tilt angle to the minimum tilt angle for receiving molten metal) The tilting control motor 8 is used to quickly drive the tilting furnace 1, and the tilting control motor 8 is controlled by the power supply circuit 1 by the control device 12.
By controlling No. 3, the tilting furnace 1 is driven by a small angle. Further, the tilting angle of the tilting furnace 1 is detected by the angle sensor 14 and the controller 1
It is supposed to be supplied to 2. The tilt control motor 8 is arbitrarily connected to the shaft 6 by connecting and disconnecting the clutch 11 to perform the tilt angle control described above. A molten metal introduction path 15 is provided below the discharge port 5 so as to guide the molten metal to a reservoir 16. One end of this storage pan 16 is rotatably supported around a fulcrum 17, and the other end is moved up and down by an elevating device 18. By the operation of the elevating device 18,
It is designed to be operated between a horizontal posture (a posture in which molten metal is accumulated) and a tilted posture (a posture in which molten metal is discharged) as illustrated. The amount of molten metal in the pan 16 is detected by a sensor 19 for detecting the weight of the pan 16, and the weight data is supplied to the controller 12. Further, a mold 20 is provided below the reservoir 16. The casting mold 20 is continuously fed one by one to a position below the ladle 16 by a conveying means (not shown) such as a turntable to receive the molten metal and is supplied. After that, it is sent to the downstream side of the transfer line.

A measuring pan 21 is provided between the pan 16 and the mold 20, and the measuring pan 21 is the pan 1
Similar to 6, it is driven by the elevating device 22 and tilts about the fulcrum 23. That is, the amount of the molten metal in the weighing pan 21 is measured by detecting its weight by the sensor 24, and based on this signal, the control device 12 raises and lowers the horizontal position or the tilted position of the pan 16. By supplying a control signal to 18, a predetermined amount of molten metal is received and then discharged into the mold 20.

Reference numeral 25 is a display device for displaying the set value of the molten metal weight to be sent to the mold 20, reference numeral 26 is a display device for displaying the set value of the cycle time of the anode produced by the mold, and reference numeral 27 is the molten metal weight. It is a setting device as an input means for setting. Further, in the case of the embodiment, the tilting furnace 1 is included in the angle sensor 14 as the tilt angle detecting means.
A method of operating a potentiometer by a pendulum attached to the pan is adopted, and a method of measuring the weight of the pan 16 is adopted as the sensor 18 as a means for measuring the pan weight. The angle may be detected, or the weight of the pan (the amount of molten metal) may be detected.

Next, the function of the control device 12 will be analyzed and explained with reference to FIG. Reference numeral 40 is a discharge amount calculation means, and the discharge amount calculation means 40 sets the amount W (kg) of the molten metal to be sent to one mold 20 and the cycle (sec) in which the mold 20 is sent. From the value (set by the setting device 27), the weight Δω (kg / sec) to be sent out by the tilting furnace 1 every predetermined cycle is calculated. Further, the data on the weight of the saucepan supplied from the weight sensor 19 is sampled at every cycle Δt (= t1−t2), and the sampling time t1,
By dividing the difference between the detection values W1 and W2 of the weight sensor 19 at t2 (weight change in the period Δt),
The instantaneous value Δωx (kg / sec) of the molten metal flow rate is calculated. That is, the data on the weight of the pan 16 is input to the instantaneous flow rate calculation means 41 to calculate the instantaneous flow rate Δωx. Further, the instantaneous flow rate Δωx is input to the correction value calculation means 42, and the correction value calculation means 42 calculates the correction value Δx. That is, the correction value calculation means 4
2 is set value Δω of emission amount per unit time and measured value
A correction value Δx obtained by multiplying the difference from the (instantaneous value) Δωx by a predetermined gain n is calculated.

Then, each of the above parameters Δω and Δx
And the tilting angle data θ supplied from the angle sensor 14, the tilting angle calculating means 43 causes the tilting speed R (rpm).
Is calculated. That is, the tilt angle calculation means 43 calculates the tilt speed R by performing the calculation R = k × (Δω + Δx) / sin ² θ from the above parameters and the constant k (hereinafter referred to as k value). ing. The k value is a coefficient for converting a function of the weight and the tilt angle into a tilt speed in accordance with the shape and size of the furnace. Then, the tilting speed R is supplied to the tilting control circuit 44, and is output as a control signal for controlling the rotation speed of the tilting control motor 8 only when a predetermined condition (detailed later) is satisfied. It has become so.

Next, the correction control means 50 for determining the control condition of the tilt control circuit 44 based on the absolute value of the amount of molten metal in the pan 16 will be described. This correction control means 5
For 0, the weight measurement value A of the saucepan 16 is compared with each threshold value described later, and the tilt angle calculating means 4 is determined based on the comparison result.
The tilt angle control signal based on the calculation result of 3 is invalidated, or the tilt angle calculation formula is changed. That is, the threshold value set in the absolute value control means 50 is composed of the following weight threshold values having the target value W as the center value (zero point). It is a line that stops tilting ..... First forced stop line WH. First forced stop release line Wh for canceling the stopped state and restarting tilting as a result of reaching the first tilting stop line WH. In the case where the weight is increased beyond the first forced stop start line WH, the forced stop is canceled before the weight starts to decrease in the case where only such a slight weight increase occurs. It is empirically known that the weight is excessively reduced unless the tilting is started. Since the weight is extremely heavy, it is essential to stop the tilting .... Second forced stop line WHH To release the stop when the second forced stop line is reached .... Second forced stop release Line Whh If the second forced stop line WHH is reached, the weight is not allowed to increase any more, so the second forced stop release line Whh is set to a value smaller than the second forced stop line WHH, The second forced stop state is released only after the weight is reduced.

On the other hand, with respect to the direction in which the weight is reduced, in order to increase the tilt angle in order to eliminate the weight reduction state, the first forced rotation line WL, the forced rotation generated as a result of reaching the first forced rotation line. The second forced rotation line WLL is the second forced rotation line WLL when the molten metal needs to be rapidly supplied as a result of further weight reduction. Both the forced rotation and the forced stop are performed with a limited time such as TL, TL / 2, Th, and TH. Further, even within the time period, when the release line is reached, this condition is prioritized to prevent excessive fluctuation of the hot water. That is,
In the case of the embodiment, in order to produce one anode (copper plate) every 30 seconds, it is necessary to send 330 kg of hot water corresponding to the weight of one copper plate into the weighing pan 21, and forced rotation and forced rotation. The stop time is set to 8 seconds for TL, Th, TH, and 4 seconds for TL / 2, for example. Each release line is set in order to prevent excessive control during the forced rotation or forced stop period.

Further, in the correction control means 50, the difference between the current and previous measured values of the pan weight is obtained, and when the difference is positive or negative, it exceeds or falls below the reference value (bias value). In such a case, the A signal or the B signal is output to change the k value in the arithmetic expression of the tilt angle calculating means 43. Therefore,
The A signal is turned on unless the current weight exceeds the reference weight by more than the previous weight, and the B signal is turned on unless the current weight is reduced by more than the reference value than the previous weight. That is, a k value smaller than the normal k value or a k value larger than a corresponding to the output of the A signal or the B signal is supplied from the k value management means 45 to the tilt control circuit 44. It is supposed to do. Then, it is judged from the A signal and the B signal whether or not the current weight changes more or less than a certain value, and the gradual control or the strong control is selected according to the result of the judgment. ing.

Next, the operation of the control device will be described with reference to the flowchart of FIG. Step SP1 Compare the measured value A of the weight of the pan 16 with the first forced rotation level WL and the first forced stop level WH. If WL ≧ A, proceed to SP2 and below, and if A ≧ WH Goes to each step after SP30. Step SP2 Using the value C1, compare the difference between the current measured value A of the saucepan weight and ΔWL with the measured value Dz of the previous saucepan weight, Dz ≤ (A
-C1) is established, that is, if the increase in the amount of molten metal in the pan 16 between the previous sampling and the current sampling is C1 or more, the process proceeds to SP3 and below, and otherwise, to SP10 and below. Go to step. The C
₁ is the bias value of the A signal, and even when the saucepan weight W is smaller than the forced rotation value W _L, if it is larger than the C ₁ value, based on the judgment in the subsequent step, A command has been issued to prohibit the forced rotation. In the example, this value is set to 10 (kg). Step SP3 Compare the measured value A of the accumulated weight with the second forced rotation level WLL,
If it exceeds this, the routine proceeds to SP50, where a control signal R for the number of revolutions of the tilt control motor is calculated in order to perform a normal tilting operation, and if it does not exceed this, it proceeds to SP4. Step SP4 Using the value C2, compare the difference between the measured values A and C2 of the current ladle gravity with the previous measured value Dz of the ladle weight, and Dz ≤ (A
If -C2) is satisfied, the process proceeds to step SP50, and if not, the process proceeds to SP11. That is, along with the determination in step 2, whether or not the forced rotation is necessary is determined depending on whether or not the increase amount A is within a predetermined range based on the C ₁ value and the C ₂ value. In the embodiment, this C ₂ value is set to 20 (kg).

Step SP10 It is judged whether Dz ≧ A + C ₃ and if YES, the operation proceeds to SP14, and if NO, the operation proceeds to the next SP11. That is, when the decreasing tendency of the hot water is judged in the step 2 and it is judged that the degree is remarkable enough to exceed the C ₃ value, the forced rotation is performed without passing through SP11, SP12 and SP13. It is designed to be controlled. Step SP11 It is determined whether the tilt angle θ is 64 degrees or less. If it is 64 degrees or less, the process proceeds to step SP14, and if it is 64 degrees or more, the process proceeds to step SP12. In step SP12, it is determined whether or not the TB timer that limits the output duration of the B signal for changing the k value is operating. If the TB timer is operating, S
Proceeding to P50, the tilt control signal is calculated using the k value, and if not operating, proceed to SP13. Step SP13 Whether the forced rotation should be judged four times in a row,
That is, the determination at SP3 is NO four times in succession.
If yes, go to SP14, N
In the case of O, the process proceeds to SP17 and subsequent steps. this is,
It is empirically known that the excessive amount of hot water is supplied when the forced rotation is continuously performed four times or more. Therefore, the determination is made to prevent this. Step SP14 It is judged whether or not the weight of the pan is equal to or more than the second forced rotation level WLL, and if YES, the routine proceeds to SP15, and if NO, proceeds to SP16. Step SP15 A control signal is output so as to forcibly perform the tilting operation for TL / 2 seconds. This time TL / 2 is a value empirically determined to move the outer circumference of the furnace by a predetermined absolute value. In step SP16 TL seconds, a control signal is output to forcibly perform the tilting motion. On the other hand, when YES is determined in the step SP13, the timer TB which cuts the forced rotation for one cycle is started in step SP17. Step SP18 Wait for the TB timer to time out. After the output of the B signal in step SP19 is stopped, the process proceeds to step SP50.

In step SP1, the weight of the saucepan A
Is determined to exceed the first forced stop line WH, it is determined in step SP30 Dz ≧ A + C ₄ , and if NO is determined in SP3.
To 1 and if YES, to SP40. The C ₄ is
It is a constant for judging whether the hot water is decreasing or increasing in the B signal, and in the case of the embodiment, if there is a tendency of decreasing 10 kg or more, proceed to SP40 to judge whether or not forced control is necessary. Proceed to SP31 to forcibly stop. In step SP31, it is determined whether or not the timer TA for controlling the output time of the A signal is in operation. If YES, the process proceeds to SP50, and if NO, the process proceeds to SP32. This is based on the empirical rule that the amount of hot water will be excessively reduced due to the time lag due to the volume of the gutter in the path from the furnace to the ladle if forced stop is performed three times or more consecutively. This is because the stop is released and automatic driving is performed. Step SP32 It is judged whether or not the forced stop has been performed three times in succession, and YE
If S, go to SP43, and if NO, go to SP33. Step SP33 The weight A of the saucepan is compared with the second forced stop level WHH. If A is less than this, proceed to step SP34, and if it is more than this, proceed to SP37. Step SP34 It is judged whether or not the forced stop has already been performed once. If the forced stop has already been performed once, the procedure proceeds to step SP35, and if not, the procedure proceeds to step SP36. Step SP3
5 Compare the saucepan weight A with the first forced stop release level Wh,
Is less than this, the process proceeds to step SP50, and if more than this, the process proceeds to SP36. Step SP36 The tilting is forcibly stopped for Ta seconds. Step SP37 The tilting is forcibly stopped for TH seconds.

On the other hand, if it is determined in step SP30 that the weight of the current ladle is less than the previous weight by C4 or more, step SP40 is whether the weight A of the ladle exceeds the second forced stop release level Whh. If YES, the process proceeds to SP41, and if NO, the process proceeds to SP50. Step SP41 It is judged whether or not the measured value A of this time is lower than the measured value Dz of the previous time by C ₅ or more, and if YES, the process proceeds to step SP31.
If NO, the process proceeds to step SP42. The constant C ₅ is a value empirically determined in order to determine whether or not the absolute value of the amount of decrease in the weight of the pan is less than or equal to a predetermined value, and is set to 20 kg in the embodiment. Step SP42 this measurement value A proceeds to the second forced rotation level WHH + C ₆ SP50 waiting to become less. This constant C ₆ is a value empirically determined in order to determine whether or not the absolute value of the amount of decrease in the weight of the pan is equal to or greater than a predetermined value, and in the embodiment, it is 1
It is set to 0 kg. Therefore, the SPs 41 and 42 can perform separate control when the change in the weight of the pan is in a certain range and when it is not.

On the other hand, when it is determined in step SP32 that the forced stop is continuous three times or more, the TA timer for controlling the output time of the signal of step SP43A is started to count time. Step SP44 Wait for the TA timer to expire. Step SP45 After stopping the TA timer, the process proceeds to step SP50.

In the above embodiment, the measured value of the weight of the pan this time is a. Various setting levels such as forced rotation and forced stop b. Compare with the reference value such as the previous measured value, and c. Absolute value of tilt angle d. Taking into account factors such as the number of forced stops and forced rotations, the forced rotation and forced stop executions and cancellations are controlled. Furthermore, the k-value change is used in combination with the above control to control the tilting motion. Any of the elements may be omitted. Further, the control method of the present invention can be widely applied to the liquid discharge operation from the tilting tank or the like.

[0020]

As is apparent from the above description, according to the present invention, the required tilt angle is calculated from the set value of the liquid amount to be discharged from the tilting furnace and the actual measured value, and the calculated tilt angle is calculated. A control signal is output so as to match the actual measured value of the tilt angle with the tilt angle, and the tilt operation is performed based on this signal, so that the liquid discharge amount can be accurately controlled. In addition, depending on the actual measured value of the liquid amount, the normal tilt angle control is disabled or the calculation formula is changed to cause the characteristics of the liquid in the tilting furnace and the shape change of the tilting furnace. Correct the error caused by tilt angle calculation by
It can be discharged more accurately without requiring special skill.

[Brief description of drawings]

FIG. 1 is a control block diagram of an entire tilting furnace according to an embodiment of the present invention.

FIG. 2 is a block diagram of a tilt angle control circuit in the tilting furnace.

FIG. 3 is a block diagram of a tilt angle control operation in the control circuit. DESCRIPTION OF SYMBOLS 1 Tilting furnace 8 Tilting control motor 12 Control device 14 Angle sensor 16 Ladle 19 Liquid amount sensor 40 Discharge amount calculation means 41 Instantaneous flow rate calculation means 42 Correction value calculation means 43 Tilt angle calculation means 44 Tilt control circuit 50 Correction Control means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Taiichi Tanaka, Onahama, Iwaki City, Fukushima Prefecture One of the first beaches at Onahama Smelter Co., Ltd. (72) Toshiyasu Midorikawa Onahama, Iwaki City, Fukushima Prefecture Inside the Onahama Smelter Co., Ltd. (72) Inventor Kiyomi Oikawa Inside the Onahama Smelter Co., Ltd., Onahama, Iwaki City, Fukushima Prefecture

Claims (3)

[Claims] 1. A tilting furnace for accommodating molten metal is tilted by a driving means so that the molten metal is continuously discharged into a pan and the tilting is carried out intermittently from the pan. In the converter control device, an angle sensor that detects the angle of the tilting furnace, a liquid amount sensor that detects the amount of molten metal contained in the pan, and detection signals of these angle sensor and liquid amount sensor The control means controls the drive means, and the control means comprises an angle detection signal, a set value of the amount of liquid to be discharged to the tilting furnace, and a tilt calculated from the detection signal of the liquid amount sensor. A tilting furnace comprising: a computing means for computing a tilt angle from the discharge amount of the furnace; and a tilting speed control means for controlling the rotation speed of the driving means according to the angle calculated by the computing means. Control device. 2. Comparing means for comparing the detection signal of the liquid amount with a reference value, and invalidating the control by the tilting speed control means according to the comparison result of the comparing means, and starting or stopping tilting. The tilting furnace control device according to claim 1, further comprising stop control means for controlling the drive means. 3. A comparison means for comparing the detection signal of the liquid amount with a reference value, and a calculation control means for controlling the calculation means according to the comparison result of the comparison means to change the calculation formula. The tilting furnace control device according to claim 1, which is characterized in that.