JP6135689B2 - Method and apparatus for controlling flow rate of molten metal in tilting type pouring machine - Google Patents

Description

  The present invention relates to a molten metal flow rate control method and apparatus for a tilting type pouring machine.

  In casting aluminum alloys and cast iron castings, it is known to use a tilting type pouring machine that tilts a ladle to inject molten metal into a mold. The inner surface of the ladle is coated with a refractory metal oxide, and according to the tilting type pouring machine, a predetermined amount of molten metal can be poured into the pouring gate of the mold while suppressing a decrease in the molten metal temperature.

  Various methods for controlling the tilting of the ladle using a tilting type pouring machine have been proposed. For example, in Patent Document 1, since it is difficult to detect the level of the pouring gate (the surface of the molten metal) with a laser sensor, instead of this, the weight of the ladle in the pouring is measured with a load cell. The molten metal weight in the ladle is obtained from the measured value, and when the difference between the molten metal weight and the molten metal weight at the previous time reaches the set value, a hot water cutting command is issued. The measured value by the load cell is affected by the inertial force caused by the fluctuation of the molten metal surface in the ladle accompanying the pouring operation. This is a proposal to reduce the influence of the inertial force.

  Patent Document 1 describes the following tilt control. That is, at the same time as the ladle starts tilting, the tilting speed is increased until a predetermined high speed is reached, and the high speed is continued until the hot water from the ladle is detected, thereby shortening the pouring operation time. Plan. When detecting the hot water, the tilting of the ladle is decelerated to a predetermined low speed, and by continuing this low speed, the amount of pouring into the mold is increased. When a hot water cutting command is issued, an operation for returning the tilt of the ladle is performed, and when the predetermined tilt return angle is reached, the tilt return speed is reduced to zero.

JP 2001-138032 A

  By the way, when the pouring of the mold into the mold with the ladle is repeated, slag (Mg oxide, etc.) on the surface of the molten metal adheres to the inside of the ladle and the spout of the ladle, and the molten metal flow path of the ladle is interrupted. The area and ladle capacity change. Therefore, even if the tilting speed and tilt angle of the ladle are controlled in the same way, the amount of hot water discharged from the ladle gradually changes. As a result, there is a problem that the filling speed of the molten metal into the mold cavity is changed, leading to the generation of defective products and the casting weight variation.

  That is, if the surface of the molten metal at the gate is higher than a predetermined level, the molten metal in the gate enters the mold cavity from the bottom, so the slag floating on the surface of the molten metal becomes molten metal toward the cavity. There is no getting involved. However, when the molten metal surface at the gate is lowered, the slag floating on the molten metal surface is caught in the molten metal and reaches the cavity, resulting in casting defects. Especially in the initial stage of pouring the mold, if the amount of molten metal poured into the mold spout decreases due to slag adhering to the ladle, the molten metal surface level does not rise rapidly, and as a result, the molten metal is caught in the molten metal The amount of slag that flows into the will increase. On the other hand, increasing the tilt of the ladle and increasing the amount of tapping to increase the level of molten metal quickly increases the momentum of the molten metal poured into the gate, and as a result, the molten metal scatters and the peripheral equipment It becomes easy to cause failure, fire and deterioration of work environment. Further, the molten metal at the gate is swelled violently, so that the slag is easily caught in the molten metal going to the cavity.

  On the other hand, it is conceivable to detect the level of the pouring gate and to control the tilt of the ladle based on the level of the pouring level. Since there is a response delay until it is reflected in the pouring flow rate, it is difficult to accurately control the hot water level.

  In view of this, the present invention proposes a method for controlling the tilt of the ladle so that the mold surface level of the mold spout rises quietly (so that undulation is suppressed) and quickly rises to a predetermined reference level.

  In order to solve the above-mentioned problems, the present invention performs tilt control of the ladle at the initial stage of pouring based on the arrival time from the tapping from the ladle in the latest pouring to the level of the pouring gate at a predetermined reference level. I corrected it.

That is, as disclosed herein, the method of controlling the molten metal flow rate of the tilting type pouring machine that tilts the ladle and pours the molten metal into the pouring gate of the mold, tilts the ladle at a predetermined tilting speed, and discharges the hot water from the ladle. After the detection, when the ladle is tilted to a predetermined tilt angle by setting a predetermined delay time, the ladle is decelerated at a predetermined deceleration until the tilt speed becomes zero. Comprising the step of controlling the tilting of the ladle to be started ,
Measure the arrival time from the last or most recent detection of the hot water until the level of the pouring gate reaches a predetermined reference level , and reduce the deviation based on the deviation from the target value of the arrival time. In this step, the delay time from the detection of the hot water to the start of deceleration of the tilt or the tilt angle of the ladle that starts the deceleration is corrected.

Moreover, the molten metal flow rate control apparatus of the tilting type pouring machine which injects the molten metal into the pouring gate of the casting mold by tilting the ladle is disclosed here.
Hot water detection means for detecting hot water from the ladle,
A hot water level detecting means for detecting the hot water level of the gate;
After the ladle is tilted at a predetermined tilting speed and the hot water is detected by the hot water detection means, the ladle is tilted to a predetermined tilt angle by a predetermined delay time. A pouring machine control means for controlling the operation of the pouring machine so as to start decelerating at a predetermined deceleration until the tilting speed becomes zero .
Measure the arrival time from the detection of the hot water until the level of the pouring gate is detected by the hot water surface level detection means from the target value of the arrival time of the previous or most recent time. based on the deviation, such that the deviation becomes small, and a correcting means for correcting the tilt control of the current of the ladle by the pouring machine control means,
The correction means corrects a delay time from detection of the hot water to the start of deceleration of the tilt, or an inclination angle of the ladle that starts the deceleration .

  According to such a method or apparatus, the tilt control of the ladle is corrected based on the latest (previous or recent multiple times) data, so there is no problem of control response delay and the tilt of the ladle is stabilized. Can be reliably controlled. As the latest data, the arrival time from the detection of the hot water until the level of the pouring gate reaches a predetermined reference level is adopted, that is, the arrival time is the condition of the molten metal coming out of the ladle due to slag adhesion etc. Therefore, the above-described correction reliably reduces the deviation from the target value of the flow rate of the molten metal flowing into the pouring gate, regardless of the variation with time of the molten metal. Therefore, it is advantageous in raising the hot water surface of the gate quietly and promptly to a predetermined reference level.

As a correction of the tilt control of the ladle, it is conceivable to correct the degree of acceleration tilt of the ladle until detection of tapping, the tilt speed reached by the acceleration tilt, or the deceleration after detection of tapping, in the present invention, correction of the delay time from the tapping detection to the deceleration start of the tilting, or you adopt tilt correction angle for starting the deceleration.

  In the case of acceleration, tilting speed, or deceleration, the amount of tapping from the ladle is likely to change greatly due to the correction. This is advantageous for preventing control overshoot.

  In addition, in the case of acceleration, tilting speed, or deceleration, the inertial force is changed by changing them, and the electrical processing method and setting values for removing the influence of the inertial force on the weight measurement are optimized. On the other hand, in the case of the delay time and the tilt angle, there is no change in the inertia force, and the optimization can be easily performed.

  It is preferable to correct the tilt control of the ladle at this time by using the integrated values for the latest plural times of the sum of squares of the difference between the measured value of the arrival time and the target value. Thereby, even if the molten metal discharge state changes greatly accidentally, the molten metal flow rate can be accurately controlled without causing overshoot due to excessive correction control.

It is preferable that the molten metal does not overflow from the pouring gate so that the molten metal surface does not fall below the reference level until the start of the pouring operation for returning the tilt of the ladle after the arrival of the molten metal surface to the reference level is detected. Controlling the tilting of the ladle after deceleration of the tilting of the ladle so that the ladle tilts at the tilting speed set by teaching ,
Obtaining the molten metal flow rate from the ladle in the second step of the previous or most recent time based on the change over time in the molten metal weight detected by the molten metal weight detecting means stored in the ladle, Based on the deviation from the target value, the tilting speed set in the teaching of the ladle until the start of the hot water cutting after the current deceleration is corrected so as to reduce the deviation .

  In this way, since the tilt control of the ladle is corrected based on the latest (last or the last several times) tapping flow rate, there is no problem of control response delay, and the tilt of the ladle can be controlled stably and reliably. it can. As a result, the flow rate of the hot water can be made constant, and it is possible to avoid that the hot water surface of the pouring gate falls below the reference level, or that the hot water surface rises excessively and overflows.

Preferably, it is set in the teaching of the ladle until the start of the hot water cutting after the current deceleration using the integrated value for the latest multiple times of the sum of squares of the difference between the measured value of the hot water flow rate and the target value. Is to correct the tilting speed . Thereby, even if the molten metal discharge state changes greatly accidentally, the hot water flow rate can be accurately controlled without causing control overshoot.

Preferably, the weight of the tapping water from the ladle is determined based on the weight of the molten metal detected by the weight detecting means, and the tapping is started when the tapping weight reaches a predetermined value. The casting weight of the molten metal poured into the mold before the end of the plurality of times of hot water cutting is obtained based on the molten metal weight detected by the weight detecting means, and based on the deviation of the casting weight from the target value , This is to correct the tapping weight at the start of the hot water cutting this time so that the deviation becomes small.

In this way, the hot water cutting control of the ladle is corrected based on the deviation from the target value of the most recent (previous or recent multiple times) casting weight, so there is no problem of control response delay and the hot water cutting is stable and reliable. This is advantageous in preventing variation in the casting weight.

  Preference is given to correcting the tapping weight at the start of the hot water cutting this time using the integrated values for the latest plural times of the sum of squares of the difference between the actually measured value of the casting weight and the target value. Thereby, even if the casting weight changes accidentally, the hot water cutting can be accurately controlled without causing overshoot of the control.

  In the case where the hot water surface area in the ladle when tapping from the ladle is different depending on the tilt angle of the ladle, it is preferable that the ladle is preliminarily set according to the tilt angle of the ladle based on the difference. Angle compensation according to the tilt angle of the ladle for tilt control of the ladle so that the amount of the molten metal poured into the gate is controlled by the set correction value according to the tilt angle of the ladle. Is to give.

  The fact that the hot water surface area in the ladle at the time of pouring is different depending on the inclination angle of the ladle means that the flow rate of the hot water from the ladle is different depending on the inclination angle of the ladle. On the other hand, since the angle compensation according to the tilt angle of the ladle is given to the tilt control of the ladle, fluctuations in the hot water flow rate due to changes in the tilt angle of the ladle can be suppressed, and the amount of pouring to the gate is increased. It becomes possible to control with accuracy.

  Preferably, a laser distance sensor is used as the molten metal surface level detecting means for detecting the molten metal surface level of the gate, and a band pass filter for cutting light having a wavelength different from that of the laser is provided in the sensor.

  That is, when the surface level of the gate is measured by the laser distance sensor, the laser light is diffused by the strong light emitted from the molten metal near the measurement point, and the sensor cannot correctly receive the reflected light from the surface. Therefore, the wavelength component different from the laser in the light emitted from the molten metal is cut by the band-pass filter, thereby enabling measurement of the molten metal surface level.

According to the present invention, the ladle is tilted at a predetermined tilting speed, and after detecting the tapping from the ladle, when the ladle tilts to a predetermined tilt angle after a predetermined delay time, In order to start the deceleration of the ladle at a predetermined deceleration rate until the tilting speed becomes zero , the mold surface of the mold tap is brought to a predetermined reference level, the previous time or the latest several times. Measure the arrival time from the detection of the hot water until the level of the pouring gate reaches the reference level, and based on the deviation of the arrival time from the target value, the delay time or inclination of the current time Because the angle is corrected, there is no problem of control response delay, the tilting of the ladle can be controlled stably and reliably, and regardless of fluctuations in the amount of molten metal coming out of the ladle due to slag adhesion etc. First, quietly and quickly move the surface of the spout to the specified reference level. It can be increased to Le, prevention of defective products, which is advantageous in dispersion prevention casting weight.

The side view which shows an example of a tilting type pouring machine. The block diagram which shows the pouring control system which concerns on embodiment. The graph figure which shows the pouring data from the pouring start which concerns on embodiment to the completion | finish of pouring. The graph figure which shows the part of the pouring initial stage of the pouring data. The graph figure which shows the middle part of the pouring of the pouring data. The graph which shows the part of the pouring end of the pouring data.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The following description of the preferred embodiments is merely exemplary in nature and is not intended to limit the invention, its application, or its use.

<Tilt-type pouring machine>
A tilting type pouring machine 1 according to the embodiment shown in FIG. 1 injects molten cast iron into a pouring gate 3 of a mold 2.

  In the tilting type pouring machine 1, 4 is a ladle, 5 is a bowl that receives the molten metal from the ladle 4 and pours it into the gate 3. The ladle 4 is received and supported by a receiving frame 6. That is, the ladle 4 is supported by the receiving frame 6 by the vicinity of the spout 7 being received by the engaging portion 8 of the receiving frame 6 and by the support roller 9 provided on the receiving frame 6. . Further, the receiving frame 6 is provided with a lock lever 13 driven by a drive cylinder 12, and this lock lever 13 engages with a lock piece 14 projecting from the lower front end portion of the ladle 4 from above. By this engagement, the ladle 4 is held by the receiving frame 6.

  The receiving frame 6 is rotatably supported by a support shaft 16 at an upper end portion of a support column erected near the tip of the horizontal frame 15. The support shaft 16 is disposed in the vicinity of the spout of the ladle 4. The receiving frame 6 is provided with an arcuate rack gear 17. A servo motor 18 as a ladle tilting means is supported near the rear end of the horizontal frame 15. The servo motor 18 is coupled to a planetary gear type reduction gear 18 ′, and a gear 19 coupled to the output shaft thereof is a two-stage gear. The other gear of the two-stage gear 21 is engaged with the arc-shaped rack gear 17. The horizontal frame 15 is suspended from each of pillars 23 erected at four positions on the front, rear, left and right sides of the base frame 22 via load cells 24 as weight detection means for the molten metal stored in the ladle 4.

  The flange 5 is supported by a support shaft 26 fixed to a support column 25 erected at the front end portion of the base frame 22 at its rear end portion, and can swing up and down. For this vertical swing, the piston rod of the drive cylinder 27 supported on the lower end of the support column 25 is connected to the support shaft 26 of the rod 5 via a lever 28. The base frame 22 is movable back and forth by wheels 29.

  In the tilting type pouring machine 1, the ladle 4 is lowered from above the receiving frame 6 and received by the engaging portion 8, supported by the support roller 9, and held by the receiving frame 6 by the lock lever 13. The The ladle is tilted together with the receiving frame 6 by the operation of the servo motor 18. The hook 5 is tilted by the operation of the drive cylinder 27, and the pouring port 32 at the front end thereof is placed on the pouring gate 3 portion of the mold 2. Since the horizontal frame 15 supporting the ladle 4 and the receiving frame 6 is suspended from the support column 23 via the load cell 24, the load cell 24 detects the total weight of the ladle 4, the receiving frame 6 and the horizontal frame 15 combined. Will do.

  Above the position where the mold 2 is provided, three laser distance sensors 31 are arranged as a hot water level detecting means for detecting the hot water level of the gate 3. An average value of values detected by the three sensors 31 is adopted as the hot water level. The laser distance sensor 31 is provided with a band-pass filter (optical element) 32 that transmits only light in the wavelength range of the laser and does not transmit other light. Different wavelength components are cut off.

  In addition, a hot water detection sensor 33 for detecting the hot water from the ladle 4 is disposed at a position obliquely above the spout 7 of the ladle 4. This hot water detection sensor 33 is an optical sensor that scans the vicinity of the tip of the spout 7 at a pitch of about 0.5 mm per bit in the lateral direction, and is adjusted in advance so that each bit is turned on by the input of molten metal light. When more than the set number of consecutive bits is turned ON, the hot water is detected.

<Pouring control>
In the pouring control system shown in FIG. 2, reference numeral 41 denotes a controller using a computer, which detects the control signals output from the casting production line, the load cell 24, the laser distance sensor 31, the hot water detection sensor 33, and the tilt angle of the ladle 4. In response to the signal from the means 34, the drive of the servo motor 18 is controlled. The controller 41 tilts the ladle 4 in a predetermined control pattern to inject a predetermined amount of molten metal into the cavity of the mold 2 and a pouring machine control means 42 for each step of the pouring control. Are provided with first to third correction means 43 to 45 for correcting the tilt control of the ladle 4 and an angle compensation means 46.

-Ladle tilt control by the pouring machine control means 42-
The pouring machine control means 42 starts the tilting of the ladle 4 simultaneously with lowering the bar 5 in response to a control signal from the casting production line when the molds 2 to be sequentially fed are positioned at the pouring position.

  Specifically, as shown in FIG. 3, the ladle 4 is tilted in the hot water direction at a predetermined acceleration until a predetermined tilting speed S1 is reached. After detecting the hot water by the hot water detection sensor 33, the tilting of the ladle 4 is decelerated at a predetermined deceleration until the tilting speed becomes zero (first step). Thereby, the hot water surface level of the gate 3 is made to reach the predetermined reference level L1.

  In FIG. 3, the level of the molten metal level is moving up and down when the tilt is decelerated because of the fluctuation of the molten metal surface when the molten metal is poured into the gate 3.

  Moreover, the tapping weight decreases when the tilt is accelerated and the tapping weight increases when the tilt is decelerated, because the influence of inertia accompanying the acceleration and deceleration of the tilt of the ladle 3 appears in the measured value of the load cell 24. It is.

  Here, the acceleration, deceleration and tilting speed S1 are set for each type of mold 2. Moreover, the acceleration control and deceleration control of the tilting of the ladle 4 are not limited to the S-shaped acceleration / deceleration control shown in FIG.

  Next, following the first step, after the tilting of the ladle 4 is decelerated, the tilting speed of the ladle 4 is controlled by teaching / playback (second step). Thereby, after the hot water surface of the pouring gate 3 reaches the reference level L1, the hot water surface is prevented from falling below the reference level L1 until the start of hot water cutting to return the inclination of the ladle 4 to the state before pouring.

  Since the tilting of the ladle 4 is suppressed by the teaching / playback control, the ladle 4 has almost no inertia. Therefore, as shown in FIG. 3, the tapping weight measured by the load cell 24 rises substantially linearly.

  Next, following the second step, the process proceeds to a hot water cutting step. That is, when a predetermined time elapses from the previous hot water detection, the process shifts to a tilting speed before hot water cutting and starts detection of the hot water cutting start timing. The hot water start timing is the time when the weight of the hot water from the ladle 4 at the present time reaches a predetermined value based on the detection signal of the load cell 24. Specifically, the hot water cutting operation is started when the hot water weight reaches a value obtained by subtracting a predetermined overshoot amount accompanying hot water cutting from the target value of the casting weight.

  Here, the amount of overshoot is between the pouring spout of the ladle 4 and the mold 2, that is, the amount of molten metal that is falling and flowing through the tub 5. An amount obtained by subtracting the estimated value of the overshoot amount from the target value of the casting weight is set as the tapping weight at the start timing of hot water cutting.

  In the hot water cutting operation, the ladle 4 is returned at a predetermined acceleration in a direction in which the inclination returns to a predetermined return speed, and after the return speed is maintained, the return speed is decreased. In FIG. 3, the amount of tapping water that is greatly swung up and down after the start of hot water cutting is due to the effect of acceleration and deceleration of the return movement of the ladle 4.

  Hereinafter, correction of the tilt control of the ladle 4 will be described in the order of steps.

-First step (Start pouring)-
The 1st correction | amendment means 43 correct | amends the tilt control of the ladle 4 based on time T1 until the hot_water | molten_metal surface of the pouring gate 3 reaches | attains the reference level L1 from the latest hot water detection. In this case, considering the fluctuation of the molten metal surface, as shown in FIG. 4, the time point when the predetermined time T2 has elapsed after the molten metal surface has reached the reference level L1 is defined as the time point when the molten metal surface has reached the reference level L1. Then, based on the latest five arrival times T1, the current pouring machine control means 42 reduces the deviation from the target value of the flow rate of the molten metal poured into the gate 3 (the flow rate of the tapping water in the ladle 4). The tilt control of the ladle 4 is corrected.

  As shown in FIG. 4, in the present embodiment, after detecting the hot water, a predetermined delay time D <b> 1 is set, that is, when the ladle 4 tilts to a predetermined tilt angle, deceleration of the tilt of the ladle 4 is started. I am doing so. The delay time D1 is set for each type of the mold 2, and this delay time D1 is corrected by the G1 gain (D1 (current value) = D1 (set value) × G1 (%)).

  Specifically, an integrated value G1d of the sum of squares of the difference between the measured value Tj1 of the latest five arrival times T1 and the target value Tt1 is obtained.

G1d = Σ [n = 1 → 5] {(Tj1n−Tt1) × | Tj1n−Tt1 |}
The integrated value G1d is compared with the reference value G1dk, and when G1d> G1dk, G1 (current value) = G1 (previous value) + G1h. When G1d <−G1dk, G1 (current value) = G1 (previous value) −G1h. In other cases, G1 (current value) = G1 (previous value). Here, G1h is the amount of change per G1 gain. However, the initial value of G1 is 100%, and an upper limit value that reaches the peak of the G1 gain and a lower limit value that reaches the bottom are set.

  When the amount of tapping water from the ladle 4 tends to decrease due to the correction of the delay time D1 by the G1 gain, the delay time D1 becomes longer, and therefore the inclination angle of the ladle 4 after deceleration increases. That is, tilt control of the ladle 4 is corrected in the direction in which the amount of hot water discharged from the ladle 4 increases, and variations in the flow rate of the molten metal poured into the gate 3 are prevented. Thereby, the hot water surface of the gate 3 can be raised to the reference level quietly and promptly.

  In addition, you may make it correct | amend the inclination angle which starts the deceleration of the inclination of the ladle 4 with G1 gain.

  In the first step, the angle compensation by the angle compensation means 46 is given to the tilt control of the ladle 4 by the pouring machine control means 42. Hereinafter, the angle compensation will be described.

  That is, in the case of a so-called fan-shaped ladle, even if the tilt angle of the ladle changes, the hot water surface area in the ladle when pouring out (the surface area of the molten metal when the molten metal overflows from the pouring spout of the ladle) is the same. Therefore, the tapping water flow rate in the ladle is the same.

  On the other hand, in the ladle 4 according to the present embodiment, the surface area of the ladle 4 when the hot water is discharged differs depending on the inclination angle of the ladle 4. The hot water flow rate is different. That is, the hot water flow rate increases as the hot water surface area increases. The angle compensation is to suppress the fluctuation of the tapping flow rate due to the change in the inclination angle of the ladle 4.

  Therefore, the angle compensation means 46 measures the surface area of the ladle 4 in advance at a predetermined angle (inclination angle of the ladle 4, for example, in increments of 5 °), and based on the surface area corresponding to the inclination angle. Compensation coefficient (%) data, which is set for each inclination angle of the ladle 4 and is inversely proportional to the hot water surface area, is provided.

  The angle compensation means 46 receives the inclination angle of the ladle 4 detected by the inclination angle detection means 34 and, based on the compensation coefficient data, obtains a compensation coefficient corresponding to the inclination angle or the target tilt speed or target inclination of the ladle 4. By multiplying the angle, fluctuations in the hot water flow rate associated with changes in the tilt angle of the ladle 4 are suppressed. Each inclination angle for which the compensation coefficient is set corresponds by linear interpolation.

  For example, in the first step, the ladle 4 is first accelerated and tilted and the tilting speed is set to S1, but the tilt angle increases as the tilt of the ladle 4 progresses. Accordingly, angle compensation is given to the tilting speed S1, and the tilting speed changes. Thereby, the fluctuation | variation of the tap water flow rate by the inclination angle of the ladle 4 can be suppressed, and the correction | amendment of tilt control of the ladle 4 by the 1st correction means 34 becomes more effective.

-Second step (during pouring)-
The second correction means 44 corrects the tilt control of the ladle 4 based on the flow rate (the amount of tapping water per unit time) Q from the ladle 4 during the latest teaching and playback. That is, the current tilt control of the ladle 4 is corrected so that the deviation from the target value Qt of the current hot water flow rate Q is reduced based on the last 5 hot water flow rates Q.

  Here, in the second step, as described above, as shown in FIG. 5, the measured value of the tapping weight by the load cell 24 increases substantially linearly by the tilt control of the ladle 4 in teaching / playback. . Therefore, the hot water flow rate Q can be accurately obtained based on the elapsed time and the hot water weight. In the present embodiment, the tapping flow rate Q is calculated with a predetermined delay time from the end of the deceleration so that the influence of the deceleration of the tilt of the ladle 4 in the first step does not appear in the measurement value of the load cell 24. I have to.

  The correction of the tilt control of the ladle 4 based on the tapping flow rate Q is to correct the teaching tilt speed S2 by the pouring machine control means 42 with the G2 gain (S2 (current value) = S2 (set value) × G2). (%)).

  Specifically, an integrated value G2d of the sum of squares of the difference between the actual measured value Qj and the target value Qt of the tapping flow rate Q in the latest five times is obtained.

G2d = Σ [n = 1 → 5] {(Qjn−Qt) × | Qjn−Qt |}
The integrated value G2d is compared with the reference value G2dk, and when G2d> G2dk, G2 (current value) = G2 (previous value) −G2h. When G2d <-G2dk, G2 (current value) = G2 (previous value) + G2h. In other cases, G2 (current value) = G2 (previous value). Here, G2h is the amount of change per G2 gain. However, the initial value of G2 is 100%, and an upper limit value that reaches the G2 gain and a lower limit value that reaches the bottom are set.

  When the amount of tapping water from the ladle 4 tends to decrease due to the correction of the teaching tilt speed S2 by the G2 gain, the tilt speed S2 increases. That is, tilt control of the ladle 4 is corrected in the direction in which the amount of hot water discharged from the ladle 4 increases, and variations in the flow rate of the molten metal poured into the gate 3 are prevented. Therefore, it is possible to avoid that the surface of the pouring gate falls below the reference level L1, or that the surface of the pouring rises excessively and overflows.

  Also in the second step, the above-described angle compensation is given to the tilting speed S2. That is, since the tilt angle increases as the ladle 4 tilts, angle compensation is given to the tilting speed S2. Thereby, the fluctuation | variation of the tap water flow rate by the change of the inclination angle of the ladle 4 can be suppressed, and the correction of the tilt control of the ladle 4 by the 2nd correction means 44 becomes more effective.

-Hot water cutting step-
As described above, the pouring machine control means 42 starts the hot water draining operation when the weight of the hot water from the ladle 4 reaches the predetermined value W3. On the other hand, the third correction unit 45 reduces the deviation of the current casting weight W from the target value Wt based on the casting weight W of the molten metal injected into the mold 2 until the end of the latest hot water cutting. Thus, the tapping weight W3 at the start of the current hot water cutting is corrected. The casting weight W is obtained by subtracting the measured value of the load cell 24 after a lapse of a certain time from the end of the hot water cutting operation from the measured value of the load cell 24 before the ladle 4 starts tilting.

  The correction by the third correction means 45 is to correct the hot water start tapping weight W3 with the G3 gain (W3 (current value) = W3 (set value) × G3 (%)).

  Specifically, an integrated value G3d of the sum of squares of the difference between the actual measured value Wj and the target value Wt of the most recent casting weight W is obtained.

G3d = Σ [n = 1 → 5] {(Wjn−Wt) × | Wjn−Wt |}
The integrated value G3d is compared with the reference value G3dk. When G3d> G3dk, G3 (current value) = G3 (previous value) −G3h. When G3d <-G3dk, G3 (current value) = G3 (previous value) + G3h. In other cases, G3 (current value) = G3 (previous value). Here, G3h is the amount of change per G3 gain. However, the initial value of G3 is 100%, and an upper limit value that reaches the G3 gain peak value and a lower limit value that reaches the bottom value are set.

  When the pouring weight W tends to increase due to the correction of the pouring weight W3 at the start of hot water cutting by the G3 gain, the hot water weight W3 at the start of hot water cutting becomes small. That is, in short, hot water cutting is started early, and an increase in the casting weight W is suppressed. When the casting weight W tends to decrease, the tapping weight W3 at the start of hot water cutting becomes large, and the reduction of the casting weight W is suppressed. This prevents variations in the casting weight.

DESCRIPTION OF SYMBOLS 1 Tilt-type pouring machine 2 Mold 3 Pouring tap 4 Ladle 5 ２４ 24 Load cell (Measuring means of molten metal weight of ladle)
31 Laser distance sensor (water level detection means)
32 Band pass filter 33 Hot water detection sensor

Claims (15)

A method for controlling the molten metal flow rate of a tilting type pouring machine that tilts the ladle and pours the molten metal into the pouring gate of the mold,
After the ladle is tilted at a predetermined tilting speed and the tapping from the ladle is detected, the ladle is tilted to a predetermined tilt angle by a predetermined delay time . A step of controlling the tilting of the ladle so as to start decelerating at a predetermined deceleration until the tilting speed becomes zero .
Measure the arrival time from the last or most recent detection of the hot water until the level of the pouring gate reaches a predetermined reference level , and reduce the deviation based on the deviation from the target value of the arrival time. A method for controlling the flow rate of the molten metal pouring machine of the tilting type pouring machine, wherein the delay time from the detection of the hot water to the start of deceleration of the tilting in the current step or the tilt angle of the ladle that starts the deceleration is corrected. . In claim 1 ,
The delay time from the hot water detection in the current step to the start of deceleration of the tilt in the current step , or the start of the deceleration , using an integrated value for the latest multiple times of the square sum of the difference between the measured value of the arrival time and the target value A method for controlling a molten metal flow rate of a tilting type pouring machine, wherein the tilt angle of the ladle is corrected. In claim 1 or claim 2 ,
Subsequent to the step, after the arrival of the molten metal surface to the reference level is detected, the molten metal does not fall below the reference level until the start of the hot water cutting to return the inclination of the ladle and the molten metal is discharged from the gate. A second step for controlling the tilting of the ladle after deceleration of the tilting of the ladle so that the ladle tilts at a tilting speed set by teaching so as not to overflow ;
Obtaining the molten metal flow rate from the ladle in the second step of the previous or most recent time based on the change over time in the molten metal weight detected by the molten metal weight detecting means stored in the ladle, The tilting type pouring machine characterized by correcting the tilting speed set by the teaching of the ladle in the second step this time so that the deviation becomes smaller based on the deviation from the target value of Of molten metal flow rate control. In claim 3 ,
The tilting speed set in the teaching of the ladle in the second step is corrected using the integrated value for the latest multiple times of the sum of squares of the difference between the measured value of the hot water flow rate and the target value. A method for controlling the flow rate of molten metal in a tilting type pouring machine. In claim 3 or claim 4 ,
In the hot water cutting step following the second step, the weight of the hot water from the ladle is obtained based on the molten metal weight detected by the weight detecting means, and the hot water cutting is started when the hot water weight reaches a predetermined value. Like
The casting weight of the molten metal injected into the mold before the end of the last or most recent rounding step is determined based on the molten metal weight detected by the weight detecting means, and the deviation of the casting weight from the target value is determined. Based on this, the molten metal flow rate control method for the tilting type pouring machine is characterized in that the molten metal weight at the start of the hot water cutting is corrected so as to reduce the deviation . In claim 5 ,
Melt tilting type pouring machine and correcting the current of the tapping weight of the hot cutting start using an integrated value of the most recent plurality of times of the sum of the squares of the difference between the measured value and the target value of the casting weight Flow rate control method. In any one of Claims 1 thru | or 6 ,
The ladle has a different surface area in the ladle when it is tapped, depending on the inclination angle of the ladle,
Based on the difference, the correction value set in advance according to the tilt angle of the ladle prevents the amount of molten metal injected into the gate from being changed by the tilt angle of the ladle. An angle compensation according to the tilt angle of the ladle is given to the tilt control of the ladle. A tilt flow type pouring machine for pouring molten metal into a mold spout by tilting a ladle,
Hot water detection means for detecting hot water from the ladle,
A hot water level detecting means for detecting the hot water level of the gate;
After the ladle is tilted at a predetermined tilting speed and the hot water is detected by the hot water detection means, the ladle is tilted to a predetermined tilt angle by a predetermined delay time. A pouring machine control means for controlling the operation of the pouring machine so as to start decelerating at a predetermined deceleration until the tilting speed becomes zero .
Measure the arrival time from the detection of the hot water until the level of the pouring gate is detected by the hot water surface level detection means from the target value of the arrival time of the previous or most recent time. based on the deviation, such that the deviation becomes small, and a correcting means for correcting the tilt control of the current of the ladle by the pouring machine control means,
The said correction | amendment means correct | amends the delay time from the said hot water detection to the deceleration start of the said tilting, or the inclination angle of the said ladle which starts the said deceleration, The molten metal flow control apparatus of the tilting type pouring machine characterized by the above-mentioned . In claim 8 ,
The correction means corrects the tilt control of the ladle this time using the integrated values of the latest multiple times of the square sum of the difference between the measured value of the arrival time and the target value. Molten metal flow rate control device. In claim 8 or claim 9 ,
Comprising weight detection means for detecting the weight of the molten metal stored in the ladle,
The pouring machine control means is configured to prevent the molten metal level from falling below the reference level until the start of the hot water returning to return the inclination of the ladle after the arrival of the molten metal level to the reference level is detected. Control the tilt of the ladle after deceleration of the tilt of the ladle so that the ladle tilts at the tilt speed set by teaching so as not to overflow from the gate ,
Obtaining the tapping flow rate from the ladle during the last or the last several times after the deceleration to the start of the hot water drainage based on the change over time in the molten metal weight detected by the weight detection means, from the target value of the tapping flow rate And a second correction means for correcting the tilting speed set by the teaching until the start of the hot water cut after the current deceleration so as to reduce the deviation based on the deviation of The flow rate control device for the tilting type pouring machine. In claim 10,
The second correction means is set in the teaching until the start of the hot water cut after the current deceleration, using the integrated value for the latest plural times of the sum of squares of the difference between the measured value and the target value of the hot water flow rate . A molten metal flow rate control device for a tilting type pouring machine, wherein the tilting speed is corrected. In claim 10 or claim 11,
The pouring machine control means obtains the tapping weight from the ladle based on the molten metal weight detected by the weight detecting means, and the hot water cutting is started when the tapping weight reaches a predetermined value. To control the operation of the above pouring machine,
The casting weight of the molten metal injected into the mold before the end of the last or the last plurality of times of hot water cutting is determined based on the amount of change in the molten metal weight detected by the weight detecting means, and from the target value of the casting weight. 3. A molten metal flow rate control device for a tilting type pouring machine, comprising: a third correcting means for correcting the weight of the hot water at the start of the hot water cutting this time so as to reduce the deviation based on the deviation . In claim 12,
Melt tilting type pouring machine and correcting the current of the tapping weight of the hot cutting start using an integrated value of the most recent plurality of times of the sum of the squares of the difference between the measured value and the target value of the casting weight Flow control device. In any one of Claims 8 thru | or 13 ,
The ladle has a different surface area in the ladle when it is tapped, depending on the inclination angle of the ladle,
Based on the difference, the correction value set in advance according to the tilt angle of the ladle prevents the amount of molten metal injected into the gate from being changed by the tilt angle of the ladle. An apparatus for controlling the melt flow rate of a tilting type pouring machine, comprising angle compensation means for providing angle compensation according to the tilt angle of the ladle to tilt control of the ladle. In any one of Claims 8 thru | or 14 ,
The molten metal level detecting means is a laser distance sensor, and includes a band-pass filter that cuts a wavelength component different from the laser of the light emitted from the molten metal, and the molten metal flow rate of the tilting type pouring machine, Control device.

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