JPH0494855A - Method and device for controlling molten metal supplying quantity into die casting machine - Google Patents

Abstract

PURPOSE:To always and surely control molten metal supplying quantity by abutting a part of a chuck holding part in a product taking-out device on end face of a biscuit part to detect the biscuit thickness, comparing this detected value with the set value and automatically correcting the molten metal supplying quantity so than the biscuit thickness comes in the range of the set value when the detected value is out of the range of the set value. CONSTITUTION:By the action of a magnetic scale 23 and a magnetic head 24, position of the surface of a slide arm 14 at a movable plate 2 side from the surface of the movable plate 2, i.e., dimension A between these can be detected. In this case, as thickness C of the movable die 4 and distance D from the surface of slide arm 14 at the movable plate 2 side to the tip face of a bar 21 at the movable plate 2 side, are beforehand informed, by abutting the tip face of bar 21 on the tip face 6a of the biscuit part 6, thickness B of the biscuit part 6 can be easily obtd. as B=A-(C+D). Then, in the case the detected thickness of the biscuit part 6 is within the prescribed set range, it is decided that the molten metal supplying quantity into the injection sleeve is within the suitable range. The molten metal supplying quantity at the next time is properly adjusted to execute actions of the supplying and the injection of molten metal.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for controlling the amount of hot water supplied in a die-casting machine.

[Prior art] Traditionally, die casting machines have always kept the casting conditions of die-cast products constant to obtain stable, high-quality products, and also to keep the thickness of the biscuit formed at the casting opening of the product constant during casting. Also, when removing the product from the mold by grasping the biscuit part, or removing the biscuit part by cutting from the product after taking it out, it is necessary to keep the grasping position of the biscuit part and the product installation position constant. In order to keep the thickness of the biscuit constant so that it is easy to remove the biscuits, or to minimize wastage of molten metal (so that the minimum amount necessary is fed into the injection sleeve each time), the molten metal is removed from the holding furnace. Efforts are being made to vary the amount of molten metal pumped by the ladle and delivered to the injection sleeve each time.

However, in reality, the amount of molten metal fed to the injection sleeve varies due to factors such as the height of the molten metal in the holding furnace, the temperature of the molten metal to be pumped out, and the accuracy of the automatic feeding device itself, which is a ladle conveyor.
It may come gradually or suddenly. Furthermore, in the early stages of operation, it was not always easy to set the amount of hot water supplied to a desired amount.

Conventionally, there have been methods to make the amount of hot water constant each time, for example, as described in Japanese Patent Publication No. 59-21261, methods that are based on the results of measuring the weight of the molten metal pumped out with a ladle, and methods that attempt to maintain the same amount of hot water each time are used. In some cases, the forward stroke of the plunger tip was measured and the thickness of the biscuit portion was calculated by calculation.

[Problems to be Solved by the Invention] In conventional systems that control the amount of hot water supplied by measuring the weight of the molten metal pumped out with a ladle, this must be done while the molten metal is being pumped from the furnace and transported to the injection sleeve. However, it was relatively difficult and troublesome to accurately detect this slight difference in weight during movement.

On the other hand, in a device that measures the forward stroke of the plunger tip during filling and calculates the thickness of the biscuit portion by calculation, and controls the amount of hot water supplied based on the result, calculations and the like must be performed, which is troublesome. Also, since the calculation is based on the forward stroke of the plunger tip, if the retraction limit of the plunger tip differs slightly for each injection,
It was not possible to accurately detect the thickness of the biscuit portion each time, and as a result, it was not possible to always control the amount of hot water supplied accurately.

[Means and effects for solving the problems] In order to solve these problems, in the present invention, when the biscuit part of a cast product formed by a die-casting machine is grabbed by a product take-out device and taken out from the mold, The biscuit part is detected by bringing a part of the chuck holding part of the product ejecting device into contact with the end face of the biscuit part, and this detected value is compared with the set value, and when the detected value is outside the range of the set value, The amount of hot water supplied is automatically adjusted so that the biscuit part falls within the set value during subsequent hot water supply.

In addition, as a device for this purpose, a predetermined device that protrudes in the axial direction of the machine from a part of the chuck holding part of the product take-out device that can also be moved in the axial direction of the machine and can come into contact with the end surface of the biscuit part of the cast product. A biscuit thickness detection device for detecting the thickness of the biscuit portion is provided in conjunction with the product removal device, and the subsequent automatic hot water supply amount is controlled in accordance with the biscuit thickness output signal from the biscuit thickness detection device. A device equipped with a hot water supply amount adjustment section was used.

[Example] Fig. 2 shows a device similar to the main part and product take-out device of a die-casting machine known in, for example, Japanese Utility Model Publication No. 19809/1980, but the method of the present invention is carried out. This device uses an improved chuck part of such a product take-out device. In Fig. 2, l is a fixed plate, 2 is a movable plate, 3 is a fixed mold, 4 is a movable mold, 4
a is a separation surface of the movable mold 4, 5 is a cast product, 6 is a biscuit part of the cast product 5, 6a is an end face of the biscuit part 6, and 7 is a product consisting of an extrusion pin 7a, an extrusion plate 7b, and an extrusion cylinder 7c. An extrusion device, 8 is an injection sleeve attached to the fixed platen 1,
9 is a plunger chip, IO is a plunger, 11 is an injection cylinder, and 12 is a product take-out device attached to the fixed platen 1.

In the product take-out device 12, for example, a slide arm 14 is provided so as to be movable back and forth in the axial direction of the machine by the action of a cylinder 13 provided on the stationary platen 1. That is,
At the tip of the piston rod 13a of the cylinder 13, an arm 15 and a plurality of rollers 1 are provided in contact with the upper and lower surfaces.
A slide arm 14 was attached via a guide rod 17 supported at 6. The slide arm 14 is provided so as to be movable in a direction perpendicular to the axis of the machine. 18
1 is a cylinder for moving the slide arm 14, and 19 is a chuck holding portion for gripping the product.

Note that the chuck holding part 19 attached to the lower end of the slide arm 14 can be attached to the slide arm 14 as needed.
The shaft 14a may be mounted so that it can be rotated by 90 degrees relative to the shaft 14a.

The chuck holding part 19 is configured to be able to move parallel to the axis of the machine when gripping the biscuit part 6 of the cast product 5 and taking it out from the movable mold 4. Chuck holding part 19
In this case, as is usually used, a plurality of claws 2
0 is provided so as to be able to grip the biscuit part 6 so as to be openable and closable.

In FIG. 1 showing one embodiment of the chuck holding part 19,
A bar 21 of a predetermined length is fixedly provided, protruding from a part of the chuck holding part 19 in the axial direction of the machine, and capable of coming into contact with the end surface 6a of the biscuit part 6. this bar 2
The length of the bar 21 is such that when a desired portion of the biscuit portion 6 is gripped with the claw 20, the tip of the bar 21 comes into close contact with the end surface 6a of the biscuit portion 6 and hangs. Of course, after bringing the tip of the bar 21 into contact with the end surface 6a of the biscuit part 6, the claw 20
The bar 21 can be closed to grasp the biscuit portion 6, or the length of the bar 21 can be adjusted as appropriate.

A bar 22 is fixed to a part of the upper surface of the movable mold 2, and extends in the axial direction of the machine through the immediate side of the slide arm 14 at the product removal position.A magnetic scale is mounted on the surface of the bar 22. 23 was installed. On the other hand, slide arm 14
A magnetic head 24 is attached to the magnetic head 24, and by the action of the magnetic scale 23 and the magnetic head 24, the position of the surface of the slide arm 14 on the movable platen 2 side from the surface of the movable platen 2, that is, the dimension A therebetween can be detected. I did it like that.

In this case, the thickness C of the movable mold 4 and the slide arm 14
The distance between the surface of the bar 21 on the movable platen 2 side and the tip surface of the bar 21 on the movable platen 2 side is predetermined. The thickness B of the portion 6 can be easily determined as B=A−(C+D).

If the detected thickness of the biscuit portion 6 is within a predetermined setting range, it is determined that the amount of molten metal supplied to the injection sleeve 8 is within an appropriate range.

On the other hand, if the biscuit part 6 is too thick, it means that the amount of hot water supplied was too large, and if the biscuit part 6 is too thin, it is found that the amount of hot water supplied is too small.In these cases, adjust the next amount of hot water appropriately. Adjust to perform hot water supply and injection operations.

In the second embodiment shown in FIG. 3.4, the thickness B of the biscuit portion 6, that is, the position of the end surface 6a, can be detected more accurately by a magnetic scale 23 provided inside the chuck holding portion 19. I did it like that.

In FIGS. 3 and 4, 19 is a chuck holding part, 20 is a plurality of claws that can be opened and closed, and 25 is a bar that is attached to the chuck holding part 19 and has its tip surface brought into contact with the separating surface 4a of the movable mold 4; 5 is a cast product.

A movable bar 26 is provided on the chuck holding part 19 so as to be movable in the axial direction of the machine so that the tip surface thereof can be brought into contact with the end surface 6a of the biscuit 6. A compression spring 27 is provided between a collar portion 28 provided on a part of the movable bar 26 and a part of the chuck holding part 19. Due to the action of this compression spring 27, the movable bar 2
6 can be reliably brought into contact with the end surface 6a of the biscuit portion 6. A flange portion 29 is provided in a portion of the movable bar 26 inside the chuck holding portion 19.

Then, the part of the bar 25 in the chuck holding part 19 is used as a magnetic scale part 23, and a magnetic head 24 is attached to a part of the flange part 29, and by the action of the magnetic scale part 23 and the magnetic head 24, the biscuit part 6 is The thickness B can be detected accurately. Then, the detected biscuit thickness B
When is within the desired range, the amount of hot water for the next injection is left as is, and when it is outside of the range, the amount of hot water supplied by the biscuit part 6 for the next injection is
The amount of hot water supplied next time is adjusted according to the amount of deviation so that the thickness of the water falls within the desired range.

The one shown in Fig. 5 is, for example,
This is an automatic hot water supply device 31 known from the above publication, in which 31a is a main body, 32 is a first arm that is rotatably driven, 33 is a second arm, 3
4 is a ladle rotatably provided at the tip of the second arm 33, and 35 is a ladle 34 which is attached to the holding furnace 3 by rotating the arm 32.
A drive source such as a motor for moving the ladle 34 between the ladle 6 and the injection sleeve 8, and a drive source 37 such as a motor for tilting the ladle 34. Drive source 3 for tilting the ladle
7, the ladle 34 can be tilted at the hot water supply port 88 of the injection sleeve 8 to supply the molten metal into the injection sleeve 8, and when the molten metal is pumped out in the furnace 36, the ladle 34 can be The amount of hot water supplied can also be changed by appropriately adjusting the angle θ of the ladle 34 when the hot water is poured into the ladle 38. Furthermore, once the molten metal 38 is pumped out from the furnace 36,
The ladle 34 is returned to a horizontal state and transported.

Therefore, when the biscuit part 6 is formed at the end of injection molding with the injection device and the mold cavity is filled with molten metal, and the thickness B of the biscuit part 6 falls within the set range, then Since the amount of hot water supplied is satisfactory, the tilting angle θ of the ladle 34 when pumping out the molten metal 38 from the furnace 36 is left as is. however,
When the thickness B of the biscuit portion 6 is outside the preset range, the tilting angle θ of the ladle 34 when pumping out the molten metal 38 from the furnace 36 is changed appropriately so that the predetermined amount of hot water is supplied. Adjust to.

That is, a setting device for setting the biscuit thickness B to a desired value, a biscuit thickness detection device as described above,
A comparator that compares the output signal from the setting device and the output signal from the biscuit thickness detection device and outputs an output signal according to the deviation, and a ladle 34 for subsequent molten metal pumping according to the output signal from this comparator. A hot water supply amount control device is provided to adjust the tilt angle θ of the hot water supply system, and the hot water supply amount is controlled by these actions.

When controlling the amount of hot water supplied based on the biscuit thickness B, for example, as shown in FIG. and the automatic correction allowable value lower limit Do, a certain alarm allowable width e larger than this automatic correction allowable width d is provided above and below the set value C, and the alarm allowable value upper limit E and the alarm allowable value lower limit are set. En is provided, and the measured value C is as long as it is above the automatic correction tolerance.

When the measured value C is in the automatic correction dead zone area F between the automatic correction allowable value upper limit Du and the automatic correction allowable value upper limit Eu and the automatic correction allowable value lower limit DD, the hot water supply amount is not corrected. When it is in the automatic correction execution area G between DD and the alarm tolerance lower limit Eo, the subsequent hot water supply amount is corrected, and if the measured value is larger than the alarm tolerance upper limit Eu or smaller than the alarm tolerance lower limit ED, At the same time as issuing an alarm, the automatic hot water supply system 31 is stopped to check for faulty parts,
Repair it or greatly correct the amount of hot water supplied next time so that it reaches the set value C.

When the measured value is in the automatic correction execution area G, when the die casting machine or automatic hot water supply device 31 starts operating,
Since the operation is not yet stable, in this case, it is determined that the pre-convergence parameter is in the area P+, and correction is made relatively quickly. For example, if the measured value falls into the automatic correction execution area G even once, it should be corrected immediately next time, or for example,
When the value is entered twice in a row as shown in a, the difference d1 between the average value M and the set value C is corrected next time.

Furthermore, if the operation becomes relatively stable after some time has passed since the start of operation, in this case, it is determined that the parameter is in the post-convergence parameter area P2, and correction is made while observing the situation more frequently. For example, if the measured value is stored in the computer every time, and the measured value falls within the automatic correction execution area G even once, it will be stored several times, for example, from the 5th measured value, starting from the last measured value M9. The average value M11 of the remaining measurement values excluding M9 and the lowest value M6 is determined, and the average value M6 is corrected by the difference in the set value C next time.

[Effect of the invention] In the present invention, as described in the claims,
When the biscuit part of a cast product formed by a die-casting machine is grabbed by the product take-out device and removed from the mold, the biscuit thickness is detected by bringing a part of the chuck holding part of the product take-out device into contact with the end surface of the biscuit part. Then, this detected value is compared with the set value, and when the detected value is outside the set value range, the amount of hot water supplied is automatically corrected so that the biscuit thickness during subsequent hot water supply is within the set value range. This makes it possible to very easily and quickly detect whether or not the biscuit portion is within the proper range. Then, we detected the biscuit thickness for each injection and automatically adjusted the subsequent amount of hot water based on that value.
Die-casting can always be performed under roughly the same injection conditions, and high-quality die-cast products can be easily obtained through automatic continuous operation.

[Brief explanation of the drawing]

Figure 1 is for explaining the apparatus etc. for carrying out the method of the present invention, Figure 1 is a front view showing the first embodiment of the present invention, and Figure 2 is a main part of the die casting machine and product removal. A vertical cross-sectional view (first part front view) showing an outline of the device part, FIG. 3 is a vertical cross-sectional view of a chuck holding part showing a second embodiment of the present invention,
4 is a sectional view taken along line IV-IV#l in FIG. 3, FIG. 5 is a front view of the automatic hot water supply device, and FIG. 6 is a diagram showing an example of a control state of the amount of hot water supplied. 1...Fixed plate, 2...Movable plate, 3...Fixed mold, 4...Movable mold, 4a...Separation surface, 5...
Casting product, 6... Biscuit part, 6a...
End face, 8... Injection sleeve, 11...
Injection cylinder, 12...Product removal device, 19.
...Chuck holding part, 20...Claw, 21.22.25...Bar 23...Magnetic scale, 24...Magnetic head, 26...Movable bar, 31...
・・Automatic hot water supply device. Patent applicant Ube Industries Co., Ltd. Figure 4 Figure 6

Claims (2)

[Claims] (1) When the biscuit part of a cast product formed by a die-casting machine is grabbed by the product take-out device and taken out from the mold, the biscuit is Detects the biscuit thickness, compares this detected value with the set value, and when the detected value is outside the set value range, automatically adjusts the amount of hot water so that the biscuit thickness during subsequent hot water supply is within the set value range. A method for controlling the hot water supply amount of a die-casting machine that has been modified to: (2) A part of the chuck holding part of the product take-out device that is movable in the axial direction of the machine and has a predetermined length that protrudes in the axial direction of the machine and can come into contact with the end surface of the biscuit part of the cast product. A bar is provided, and a biscuit thickness detection device for detecting the thickness of the biscuit portion is provided in conjunction with the product take-out device section, and the water supply amount is adjusted to automatically control the subsequent water supply amount in accordance with the biscuit thickness output signal from the biscuit thickness detection device. A hot water supply amount control device for a die-casting machine with a section.