JPH05245612A - Method for controlling supply of molten metal in die casting machine - Google Patents

Abstract

PURPOSE:To always automatically correct the setting time of an interlocking timer for controlling the time from the prescribed movement time at a machine main body side regarded as the completion of the pouring of the molten metal with a ladle to the following drawing-up movement starting time of the ladle waited at retreating position on a melting furnace. CONSTITUTION:The setting time of the interlocking timer 18 is automatically corrected in a direction for eliminating the time lag between the timing for completing the arrival to the advancing limit position, by the ladle and the timing for generating the pouring start permitting command with an interlocking time correcting part 17 by referencing to the measured information of a cycle monitoring timer 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot water supply control method for a die casting machine, and in particular, it pumps a molten metal from a melting furnace by a predetermined amount with a ladle, and then advances the ladle from a retracted position to an advance limit position. After that, the present invention relates to a hot water supply control method in a die casting machine in which the molten metal in the ladle is poured into the injection sleeve.

[0002]

2. Description of the Related Art In a cold chamber type die casting machine in which a molten metal is poured into an injection sleeve by a ladle, the ladle waits at a retracted position on the melting furnace from a predetermined operation point on the machine body side where it can be considered that the molten metal has been poured. The interlock timer is provided to control the time until the start of the next pumping operation of the ladle, and the operation of the machine body and the operation of the ladle (water heater) are synchronized by the set time of this interlock timer. I am trying.

FIG. 4 shows an operation control flow during an automatic operation cycle of a water heater in such a conventional die casting machine. As shown in the figure, in step ST51, the water heater arm is moved forward, and in step ST52 it is asked whether or not the water heater arm has reached the forward limit. When the water heater arm reaches the forward limit (the tip of the water heater arm is (When the ladle reaches the pouring port of the injection sleeve) proceeds to step ST53.
In step ST53, it is inquired whether or not the machine body is in a pouring acceptance state and the pouring command is ON (the pouring start permission command is ON). If this is ON, the process proceeds to step ST54. In step ST54, the ladle is rotated to pour the molten metal into the injection sleeve from the pouring port, and in the next step ST55, the water heater arm is retracted so that the ladle stands by at a predetermined position on the melting furnace. To step ST56. In step ST56, an interlocking timer for controlling the time from the predetermined operation time of the machine body side, which can be considered as the completion of pouring of the ladle, to the start time of the next pumping operation of the ladle waiting at the retracted position on the melting furnace. Ask if it has been UP (whether it has reached the start point of the next pumping operation of the ladle), and if it is UP, proceed to step ST57, pump up the molten metal from the melting furnace with the ladle, and go to step ST51. After returning, the same series of operations are repeated.

That is, by setting the set time of the interlocking timer to a desired value by the operator, from the start of the pumping operation of the water heater to the time when the ladle at the tip of the water heater arm reaches the pouring port of the injection sleeve. , And the cycle time of the die casting machine body side, consider as much as possible between the timing when the water heater arm reaches the forward limit and the timing when the machine body enters the pouring acceptance mode and the pouring command is turned on. I was trying not to shift.

[0005]

By the way, in the above-mentioned prior art, since the operator sets the set time of the interlocking timer, the operator is likely to vary the set time. For example, the set time of the interlock timer is set. If it is too short (when the pumping operation starts too early), the ladle will have time to wait on the pouring port of the injection sleeve, and the temperature of the molten metal in the ladle will drop, resulting in poor casting. Caused a problem. On the contrary, if the setting time of the interlocking timer is too long (when the start of the pumping operation is too late), even if the machine main body enters the pouring acceptance mode and the pouring command is turned ON, the ladle is the pouring port of the injection sleeve. However, since the total cycle time has not been reached, there is a problem that the overall cycle time becomes long and the operating efficiency decreases. For this reason, a lot of experience and knowledge are required to set the set time of the interlocking timer to an appropriate value, and many retries are required, which is a complicated and tired work.

Moreover, since the molten metal surface of the melting furnace fluctuates up and down during long-term automatic continuous operation, even if the set time of the interlocking timer is appropriate when the molten metal surface of the melting furnace is at the reference position. When the height of the molten metal surface of the melting furnace is higher than the reference position, the time required for pumping is shortened and the same problem as above occurs, and when the height of the molten metal surface of the melting furnace is lower than the reference position, pumping is performed. As a result, the time required for the process has become long and the same problem as described above has occurred. That is, in the prior art, since it is not possible to automatically change the set time of the interlocking timer in response to the vertical movement of the molten metal surface of the melting furnace,
In order to always obtain the optimum interlocking timer set time according to the height change of the molten metal surface of the melting furnace, the operator had to adjust the set time of the interlocking timer on a machine-by-machine basis. It is difficult to deal with this in the field due to the popularization of operation and the lack of skilled workers.

The present invention has been made in view of the above points,
The purpose is to control the time from the predetermined operation time on the machine body side where it can be considered that the pouring of the ladle is completed to the start time of the next pumping operation of the ladle waiting at the retracted position on the melting furnace. It is to provide a hot water supply control method for a die casting machine that can automatically correct the set time of the interlocking timer to an optimum value.

[0008]

To achieve the above object, the present invention draws a predetermined amount of molten metal from a melting furnace filled with molten metal with a ladle, and then advances the ladle from a retracted position to an advance limit position. After that, in the hot water supply control method in the die casting machine in which the molten metal in the ladle is poured into the injection sleeve from the hot water supply port of the die casting machine, the ladle moves to the forward limit position before the timing of the pouring start permission command. If the ladle has reached the forward limit position by the timing of the pouring start permission command, the interlock timer is set if Save time,
As a result, the interlock timer is set to control the time from the predetermined operation time on the machine side, which can be considered as the completion of pouring of the ladle, to the start time of the next pumping operation of the ladle waiting in the retracted position on the melting furnace. The time is automatically corrected in a direction in which there is no deviation between the timing when the ladle reaches the forward limit position and the timing when the pouring start permission command is generated.

[0009]

[Operation] The automatic cycle operation of the main body of the die casting machine and the automatic cycle operation of the water heater are monitored and measured for each shot, and the pouring start permission command generation timing (pouring command O
When the ladle reaches the forward limit position and is waiting before N), the time from the time when the ladle reaches the forward limit position to the pouring command ON is measured, and this is n shots (for example, 4 shots). ) If continuous, the set time of the interlocking timer is lengthened by a predetermined amount. When the ladle has not reached the forward limit position by the timing of the pouring start permission command (pouring command ON), the ladle reaches the forward limit position from the time of the pouring command ON. Up to n shots (for example, 4 shots), the set time of the interlocking timer is shortened by a predetermined amount.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to one embodiment shown in FIGS. FIG. 1 is a diagram showing a simplified functional block of a control system of a die casting machine according to this embodiment. In FIG. 1, reference numeral 1 is a microcomputer (microcomputer) that controls the operation of the die casting machine body and machine peripherals (product take-out machine, spray device, water heater), etc.
Is a sensor group composed of a large number of sensors provided in each part of the machine body and machine peripherals, and 3 is a large number of drive sources for driving and controlling a large number of drive sources provided in each part of the machine body and machine peripherals. Driver group composed of driver circuits, 4
Is a key input device provided on the front surface of the machine body, and 5 is a water heater controlled by the microcomputer 1 via the driver group 3.

FIG. 2 is a view showing an example of the water heater 5, wherein 21 is a base of the water heater, 22 is a first arm rotatably attached to the base 21, and 23 is a first arm. 2nd arm rotatably attached to the tip of 1 arm 22, 2
Reference numeral 4 denotes a ladle rotatably attached to the tip of the second arm 23. Further, 25 is a melting furnace (crucible) filled with a molten metal obtained by melting an aluminum alloy or the like,
26 is an injection sleeve on the machine body side, 27 is a hot water supply port provided on the injection sleeve 26, and 28 is a plunger tip. The first and second arms 22 and 23 and the ladle 2
4 is driven by a DC motor or the like, and the first and second arms 22,
23 is a forward limit position (raddle 24 shown in solid line in FIG.
Is a position where the molten metal can be poured into the hot water supply port 27), and a retracted position (a position where the ladle 24 stands by on the melting furnace 25 and a position where the ladle 24 is immersed in the melting furnace 25). It is designed to move between. When the arm is at the forward limit position, the molten metal in the ladle 24 is poured from the hot water supply port 27 into the injection sleeve 26 by rotating the ladle 24 from the position indicated by the solid line. By moving the tip 28 forward, the molten metal is injected and filled into the casting mold.
Further, after the pouring is completed, the arm is returned to the retracted position, and the ladle 24 first waits on the melting furnace 25, and the pumping operation is started at an appropriate timing thereafter, so that the ladle 24 is melted. After being immersed in 25, the arm is pulled up, and then the arm immediately moves to the forward limit position. The mechanism of the water heater 5 having such a configuration is only one example, and any other arm shape, arm operation, etc. can be adopted.

The microcomputer 1 shown in FIG. 1 controls the operation of the die casting machine body and peripheral machines (control of the entire casting process).
Also, various processing such as calculation / storage processing of measured data, calculation / judgment processing such as non-defective / defective product judgment processing, abnormality judgment processing, display control processing of an output image of a display device (not shown), and the like are executed. The microcomputer 1 is actually composed of various I / O interfaces, ROM, RAM, CPU, etc., and executes various processes by various programs created in advance. Setting unit 11, machine body control unit 12, unloader control unit 1
3, the following description will be made assuming that the spray control unit 14, the water heater control unit 15, the cycle monitoring timer 16, the interlock timer correction unit 17, the interlock timer 18 incorporated in the water heater control unit 15, and the like are provided.

The operating condition setting unit 11 stores various operating condition values input by the key input device 4 or the like in a rewritable form. As this operating condition value,
For example, control conditions for each stroke of the machine body (injection / filling pressure and speed conditions, mold opening / closing conditions, eject conditions, etc.), product unloader control conditions, spray device control conditions (release agent, air spray conditions, etc.) ), Control conditions of the water heater 5 (arm operating conditions, pouring and drawing hot water control conditions, etc.).

The machine body controller 12, the take-out machine controller 13, the spray controller 14, and the water heater controller 15
Is based on the operating process control program created in advance and the setting condition values stored in the operating condition setting unit 11,
The driver group 3 (motor driver, hydraulic pressure, etc.) is referred to while referring to the measurement information from the sensor group 2 (position sensor, pressure sensor, temperature sensor, etc.) arranged in each part and the timekeeping information from a clock incorporated in itself. A corresponding drive source is driven and controlled via a cylinder driver, a heater driver, etc.), thereby driving and controlling each part of the machine body, the product take-out machine, the spray device, and the water heater 5 to execute a series of casting strokes. ..

Here, the interlock timer 18 in the water heater controller 15 waits on the melting furnace 25 from a predetermined operation time on the machine body side where it can be considered that the ladle 24 has completed pouring. The time value that defines the time until the start of the next pumping operation can be set to be rewritable. This interlocking timer 18 is set by the arrival of a signal (for example, an injection start signal or the like) that can confirm the completion of pouring, starts timing (counting), and when the set time value is counted up, the fact that this is done is controlled by the water heater control. The unit 15 is notified and reset. And
When the count-up signal from the interlocking timer 18 arrives, the water heater controller 15 starts the pumping operation of the ladle 24, the ladle 24 is immersed in the melting furnace 25, and the ladle 24 is pulled up from the melting furnace 25 (metal melt When a series of operations of pumping up the water heater arm is performed and the machine main body enters the pouring acceptance state (when the mold clamping is completed), the pouring command is ON (the pouring start permission command is ON), Ladle 2
The above-described pouring operation according to No. 4 is performed.

In the present embodiment, as described above, the interlock timer correction unit 17 always refers to the measurement information of the cycle monitoring timer 16 for the set time of the interlock timer 18 which affects the casting quality and the cycle time. It is designed to be automatically corrected to an appropriate value. Hereinafter, a method of correcting the set time of the interlocking timer 18 will be described with reference to the processing flow of FIG.

FIG. 3 is a process flow of the fully automatic setting mode of the linked timer setting time. In step ST1 of FIG. 3, it is asked whether or not the pouring is completed, that is, whether or not a signal (for example, an injection start signal or a mold opening start signal) capable of confirming the pouring completion has arrived. YES
If (pouring of molten metal is completed), the process proceeds to step ST2. If NO, the process of step ST1 is repeated. Step ST2
Then, it is asked whether or not the water heater arm has reached the forward limit, and if YES (arm forward limit), the process proceeds to step ST3, and if NO, the process proceeds to step ST4. Step ST3
Then, the measurement by the cycle monitoring timer 16 is started and the process proceeds to step ST5. At step ST4, the cycle monitoring timer 16 is reset to stop the measurement by the cycle monitoring timer 16 and the process also proceeds to step ST5. In step ST5, it is determined whether or not the machine body is ready to receive the pouring liquid (when the mold clamping is completed) and the pouring command is ON (the pouring start permission command is ON). In the case of), the process proceeds to step ST6, and if NO, the process returns to step ST1.

In step ST6, it is asked whether or not the cycle monitoring timer 16 has measured the value. If YES, the process proceeds to step ST7, and if NO, the process proceeds to step ST11. Here, the determination result of step ST6 is YES means that the pouring command has not been turned ON yet at this point, even though the water heater arm has reached the forward limit, It means that the forward limit was reached too early. At step ST7, it is determined whether such a situation (phenomenon) that the water heater arm operates too fast continues for n consecutive shots (n is an arbitrary integer of 2 or more, for example, 4 times in this embodiment). If the answer is YES, the operation of the water heater arm tends to be too early, and the process proceeds to step ST8. If the answer is NO, there is a possibility of a sudden situation, so the process returns to step ST1. Step S
At T8, each measurement time for n shots by the cycle monitoring timer 16 (time from completion of reaching the forward limit of the water heater arm to turning on of the pouring command, that is, waiting on the injection sleeve 26 of the ladle 24) The average value of (time) is calculated and the process proceeds to step ST9. In step ST9, it is asked whether or not the calculated average value is within a predetermined allowable range. If YES (within the allowable range), it is determined that the correction of the set time of the interlocking timer 18 is not necessary, and the step ST1
If NO, the process proceeds to step ST10 because it is necessary to correct the set time of the interlocking timer 18. Step ST1
At 0, the set time of the interlocking timer 18 is, for example, (current set time) + (calculated average value in step ST8) or (current set time) + (calculated average value in step ST8 × number). 10%) to increase the set time of the interlocking timer 18 by a predetermined amount, and then, in step S
Return to T1. The processing in steps ST7 to ST10 described above is performed by the interlock timer correction unit 17.

The fact that the decision result in the step ST6 is NO means that the water heater arm has not reached the forward limit even after the pouring command is turned on. Therefore, in step ST11, the measurement by the cycle monitoring timer 16 is started, and step S
Go to T12. In step ST12, it is asked whether or not the water heater arm reaches the forward limit. If YES (arm forward limit), the process proceeds to step ST13, and if NO, the routine of step ST12 is repeated. Step ST13
Then, even though the pouring command is turned on, the water heater arm has not reached the forward limit yet and the time when the water heater arm reaches the forward limit is too late (phenomenon). (N is an arbitrary integer of 2 or more, for example, four times in this embodiment), whether or not it is continuous,
If YES, it is determined that the operation of the water heater arm tends to be too slow, and the process proceeds to step ST14. If NO, there is a possibility of a sudden situation, so the process returns to step ST1. Step ST
In 14, the average value of each measurement time for n shots by the cycle monitoring timer 16 (the time from when the pouring command is turned ON until the water heater arm reaches the forward limit) is calculated, and the process proceeds to step ST15. .. In step ST15,
It is asked whether or not the obtained average value is within a predetermined permissible range. If YES (within the permissible range), it is determined that it is not necessary to correct the set time of the interlocking timer 18, step ST.
If NO in step 1, the process proceeds to step ST16 because it is necessary to correct the set time of the interlocking timer. Step ST
In 16, the set time of the interlocking timer 18 is, for example, (current set time) − (calculated average value in step ST14)
Or (current setting time) − (calculated average value in step ST14 × several 10%) to decrease the setting time of the interlocking timer 18 by a predetermined amount, and then, in step ST1 Return to. In addition, the above-mentioned step ST13-
The processing in step ST16 is also the same as that of the interlocking timer correction unit 1.
Performed by 7.

In this embodiment in which the set time of the interlock timer 18 is automatically corrected, even if the set time of the interlock timer by the operator is unsuitable, this is automatically set to the optimum value. Since it is performed again, it is possible to set the interlocked timer by an innocent operator without requiring a wealth of experience and knowledge for setting the interlocking timer, and troublesome retries. Moreover, even if the height of the molten metal surface of the melting furnace fluctuates up and down during a long-time automatic continuous operation and the time required for pumping fluctuates, the set time of the interlocking timer is automatically changed to the optimum value. Therefore, the gap between the completion timing of the ladle reaching the forward limit position and the generation timing of the pouring start permission command is always reduced as much as possible, so that the temperature of the molten metal caused by the ladle waiting on the injection sleeve It is possible to avoid deterioration and enable good casting, and the overall cycle time is shortened as much as possible to improve operating efficiency.

[0021]

As described above, according to the present invention, the next pumping operation start time of the ladle waiting at the retracted position on the melting furnace from the predetermined operation time of the machine body side where it can be considered that the pouring of the ladle has been completed. Since the set time of the interlocking timer for controlling the time up to the time can be automatically corrected to the optimum value at all times, it is possible to avoid the temperature drop of the molten metal and enable good casting, and the total cycle time is as long as possible. It has a remarkable effect that it can be shortened to improve the operation efficiency.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a simplified functional block of a control system of a die casting machine according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of a water heater in a die casting machine according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a flow of automatic correction processing of a set time of an interlocking timer according to an embodiment of the present invention.

FIG. 4 is an explanatory diagram showing an operation control flow of a water heater in a conventional die casting machine.

[Explanation of symbols]

 1 microcomputer (microcomputer) 2 sensor group 3 driver group 4 key input device 5 water heater 11 operating condition setting unit 12 machine body control unit 13 take-out machine control unit 14 spray control unit 15 water heater control unit 16 cycle monitoring timer 17 interlocking timer Correction unit 18 Interlocking timer 22 First arm 23 Second arm 24 Ladle 25 Melting furnace 26 Injection sleeve 27 Hot water inlet 28 Plunger tip

Claims (2)

[Claims] 1. A ladle is used to pump a predetermined amount of molten metal from a melting furnace filled with the molten metal, and then the ladle is advanced from a retracted position to an advanced limit position, after which the molten metal in the ladle is supplied to a die casting machine. In the die-casting machine that pours the molten metal into the injection sleeve, the next pumping operation of the ladle waiting at the retracted position on the melting furnace from the predetermined operation time on the machine body side where the pouring of the ladle can be regarded as completed. The set time of the interlocking timer for controlling the time until the start time is automatically corrected so that there is no deviation between the timing when the ladle reaches the forward limit position and the timing when the pouring start permission command is generated. A method for controlling hot water supply in a die casting machine characterized by the above. 2. The set time of the interlocking timer according to claim 1, wherein when the ladle reaches the forward limit position and stands by before the generation timing of the pouring start permission command, the setting time of the interlocking timer is lengthened, A hot water supply control method in a die casting machine, wherein when the ladle has not reached the forward limit position by the timing of the pouring start permission command, the set time of the interlocking timer is shortened.