JP3154212B2 - Ladle for die casting machine hot water supply device and hot water supply amount control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ladle for a hot water supply apparatus for a die-casting machine, and more particularly, to a method for controlling the amount of hot water supplied to improve the accuracy of the amount of molten metal supplied by the ladle and the ladle thereof.

[0002]

2. Description of the Related Art Generally, an automatic hot water supply apparatus using a ladle is used to supply a molten metal such as an aluminum molten metal from a molten metal warming furnace to an injection sleeve attached to a fixed die plate of a die casting machine. FIG. 4 is a side view showing an example of a conventional automatic hot water supply apparatus. That is, the automatic water heater mainly includes the first arm 15, the second arm 16, the third arm 1
A link mechanism 19 comprising a seventh arm and a fourth arm 18; a chain 24 running in the second arm 16;
5 comprises a chain device consisting of a chain 23 running inside and drive sources 24 and 25 for driving them.

In order to pump up a predetermined amount of molten aluminum by the angle of inclination of the ladle, the ladle 14 is inclined around a ladle pouring shaft 13 at a predetermined angle by a ladle rotating device composed of chains 23 and 24. Is lowered by the link mechanism 19 to quantitatively pump the molten aluminum 12 in the crucible 10 of the molten metal warming furnace. After this, Ladle 14
Is raised by a link mechanism 19, and then leveled, and the pumped aluminum melt is pierced at an upper portion of an injection sleeve 26 attached to a fixed die plate 20 of a die casting machine and moved to a pouring port 27 side. As shown in the figure, the ladle 14 is rotated and supplied. (See JP-A-60-212049)

As described above, the ladle 14 inclined at a predetermined angle in order to pump a fixed amount of molten aluminum is provided with the link mechanism 19.
Is actuated and lowered to pump up the molten aluminum 12 in the crucible 10 of the molten metal warming furnace by measuring and controlling it. The ladle 14 is used to make the supply amount of the molten aluminum variable.
The pouring shaft 13 is tilted with its angle changed by the chains 23 and 24, and the tilting controls the supply amount.

[0005]

By the way, in the conventional automatic hot water supply apparatus configured as described above, in order to give priority to productivity and maintenance management, the pumping of the molten aluminum to the ladle and the measurement control are performed within the same crucible 10. Was configured to do in place. And the ladle 14 at this weighing position
Has the largest opening area (free surface portion). As described above, the measurement control of the molten aluminum is performed by adjusting the rotation angle of the ladle 14 around the pouring shaft 13, but since the opening area of the ladle 14 is large, the adjustment of the rotation angle of the ladle is extremely fine. I had to decide. In addition, when measuring the molten aluminum, in addition to the accuracy of the rotation angle of the ladle, mechanical factors such as the buoyancy of the ladle and backlash of the chain that transmits rotation must be taken into consideration. Could not be ignored.

As described above, in the conventional automatic water heater,
The quantitative supply accuracy of the supply amount of the molten aluminum has been achieved by increasing the accuracy of the rotation angle of the ladles, but the present inventor has found that this can be achieved by reducing the surface area of the ladles. Hereinafter, an outline of the principle will be described.

First, the relationship between the amount of hot water supplied to the ladle and the injection sleeve will be described. FIG. 5 shows a cross-sectional view of the injection sleeve 26. This figure shows an injection sleeve 2 with a cross section A ₁
6, the molten aluminum from the ladle is supplied to the pouring port 27,
This shows a state in which the injection plunger 28 is driven by a shot cylinder (not shown) from the right position shown by the solid line to the left position shown by the broken line, and extrudes the molten aluminum into the upper left cavity (not shown). Usually, the molten aluminum is supplied to the injection sleeve 26 in order to press the molten aluminum into the cavity. It is necessary to control the supply amount of the molten aluminum in the injection sleeve 26 within ± 2% in order to maintain the quality of the product.

FIG. 6 is a sectional view showing the configuration of the ladle.
The ladle 14 is inclined at an angle of θ degrees from the horizontal, and the pouring amount of the molten aluminum is determined. Usually, this angle is configured to be controllable at ± 0.2 ° in order to maintain the accuracy of the hot water supply amount.

As an example, the cross-sectional area of the surface of the molten aluminum when the ladle 14 is inclined by θ degrees is A _2, and the ratio A ₂ / A ₁ of the cross-sectional area to the cross-sectional area A ₁ of the injection sleeve 26 is K. Then, this value is usually set to K = 10. That is, the cross-sectional area of the surface of the ladle is configured to be about 10 times larger.

In the configuration of the injection sleeve 26 shown in FIG. 5, if the thickness of the biscuit 29 is B, the variation is ΔB, and the variable hot water supply of the injection sleeve is ΔV ₁ , the variable hot water supply ΔV ₁ at the injection sleeve is It is shown by the following equation.

± ΔV ₁ = A ₁ × ± ΔB (1)

On the other hand, in the configuration of the ladle 14 shown in FIG. 6, the variation amount Δh of the molten metal surface and the variation hot water supply amount
Assuming that ₂ , the variable hot water supply amount ΔV ₂ in the ladle is expressed by the following equation.

± ΔV ₂ = A ₂ × ± Δh (2)

The sectional area A ₁ of the injection sleeve 26 and the ladle 1
Since the ratio K of the cross-sectional area of the surface of _No. 4 to A ₂ is K = A ₂ / A ₁ , the variable hot water supply Δ
V is represented by the following equation from the above equations (1) and (2).

± ΔV = K · A ₁ × ± Δh (3)

Next, let us consider reducing the variable hot water supply amount ± ΔV. Since the cross-sectional area A ₁ of the injection sleeve 26 is constant, it is necessary to reduce the K · Delta] h in the above (3). Sectional area of the injection sleeve 26 A ₁ and ladle 1
It is apparent that the ratio K of the cross-sectional area of the surface of No. 4 to the cross-sectional area of A ₂ is K = 10, and if this is changed to K = 1, the allowable value of Δh increases. As a result, it is possible to increase the allowable value θ of the rotational accuracy of the ladle 14. That is,
This is an outline of the principle for reducing the surface area of the ladles and increasing the allowable value of the rotation accuracy of the ladles.

[0017]

According to the present invention, a member for reducing the surface area of the surface of the molten aluminum is attached to the ladle at the measuring operation position of the ladle, and this member partially covers the surface of the molten metal which has been pumped into the ladle. A method of controlling a hot water supply amount of a ladle for a die-casting machine hot water supply device, wherein the variation in the hot water supply amount of the weighed molten metal is minimized as described above. Further, the present invention is a ladle for a die casting machine hot water supply device, wherein the member for reducing the surface area of the molten metal surface is fixedly provided on the ladle. Further, the present invention is a ladle for a die casting machine hot water supply device, wherein the member for reducing the surface area of the molten metal surface is lowered only at the time of the weighing operation and installed on the molten metal surface of the ladle.

[0018]

[Function] By reducing the surface area of the molten metal surface at the weighing operation position of the ladder, the allowable value of the accuracy of the rotation angle of the ladder for controlling the precision of the quantitative supply of the molten metal is increased, and the precision of the quantitative supply of the molten metal is enhanced. Can be.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a ladle for a hot water supply device for a die-casting machine and a method for controlling a hot water supply amount of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing a configuration of a ladle according to one embodiment. A ladle 14 of an automatic water heater made of ceramics or stainless steel has the same shape as a conventional one having a rotating shaft 13. The only difference is that the aluminum or molten metal 12 is pumped up, and the bottom of the plate 30 made of ceramics or stainless steel, whose bottom is installed horizontally with respect to the molten metal surface P, is not easily adhered to the concave shape.
Is provided over both sides of the flange portion and fixed with screws 31.

Therefore, a part of the surface P of the molten aluminum 12 pumped by the ladle 14 is covered by the ceramic or stainless steel plate 30, and the surface area is reduced accordingly. If the molten aluminum 12 is weighed in this state, the allowable value of the rotation angle is larger than when the plate 30 is not provided, so that the variation of the variable hot water supply amount ΔV can be reduced, and the vibration of the die casting machine is troublesome. It is possible to improve the precision of fixed-quantity supply without performing the above. Therefore,
It can contribute to the improvement of the product quality of the die casting machine, the accuracy of the thickness of the biscuit, and the improvement of the injection control.

Next, another embodiment will be described with reference to FIGS. 2 (A) and 2 (B). This example is a case of a ladle used with almost no change in hot water supply. A ladle 14 of an automatic water heater made of ceramics or stainless steel has a rotating shaft 13 like the one shown in FIG. Brackets 34 are provided so as to be fitably attached or detached so as to cover the ladle with fastening bolts 35 over flange portions on both sides of the ladle 14. A support rod 32 is fixed to the center lower portion of the bracket 34 with bolts 33, and a ceramic plate 30a is fixed to a tip of the support rod 32 at a predetermined angle (angle of a molten metal surface where a fixed amount of molten aluminum is formed). ing.

Therefore, a part of the surface P of the molten aluminum 12 from which the ladle of this example is drawn is covered by the ceramic plate 30a, and the surface area is reduced by that much.
If the molten aluminum 12 is measured in this state, the permissible value of the rotation angle is larger than when the plate 30 is not provided, so that the variation of the variable hot water supply amount ΔV can be reduced. When changing the angle of the ladle 14 to change the supply amount of the aluminum melt to another supply amount, the plate corresponding to the angle is replaced with the ladle with the tightening bolt 34 and attached, so that accurate measurement can be performed. Can be.

Next, another embodiment will be described with reference to FIG. In this example, a ceramic or stainless steel plate 30b is fixed to the tip of an operating rod 37 of an air cylinder 36 attached to the first arm 15 of the automatic water heater, and is raised when the ladle 14 draws the molten aluminum 12. At the time of weighing, the air cylinder 36 is operated to lower the operating rod 37 so as to be brought into contact with the surface P of the molten aluminum 12. Although not shown, the operating rod 37 is provided with a mechanical stopper and a stroke adjusting screw for fine adjustment so as to adjust the positioning accuracy.

Therefore, in the ladder 14 of this embodiment, a part of the surface P of the molten aluminum 12 pumped up in the same way as the ladder shown in FIG. Since the allowable value of the rotation angle is larger than that in the case where the plate 30b is not provided, the variable hot water supply amount ΔV
Variation can be reduced. Further, since the plate 30a can be retracted during the pumping and pouring of the molten aluminum, the operation can be performed without affecting the pumping operation and pouring operation of the molten aluminum. Further, even if the inclination angle of the ladle is changed at the time of measuring the molten aluminum, it can be handled by a fine adjustment device using screws.

In each of the three examples described above, the supply amount of the aluminum melt pumped to the ladle is the plate 30, 30a, 30
Naturally, the design is made in consideration of the quantitative amount including the part where b is immersed in the molten aluminum. Although the example of the molten aluminum has been described, it can be used for measuring and controlling the molten zinc and other molten metals.

[0027]

As described above, according to the ladle for a die-casting machine hot water supply apparatus and the hot water supply amount control method of the present invention, the allowable value of the rotational accuracy of the ladle is increased by reducing the surface area of the ladle with a simple structure. And the variable supply amount can be reduced. For this reason, the measuring accuracy of the molten metal of the automatic hot water supply device can be improved, and the variation of the hot water supply amount can be reduced, and the non-defective product rate of the die-cast product can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a ladle for a die casting machine hot water supply apparatus according to an embodiment of the present invention;

FIGS. 2A and 2B are a cross-sectional view and a front view showing a configuration of a ladle for a die-casting machine water heater according to another embodiment of the present invention;

FIG. 3 is a cross-sectional view illustrating a configuration of a ladle for a die casting machine hot water supply apparatus according to another embodiment of the present invention;

FIG. 4 is a side view showing an example of a configuration of a conventional automatic hot water supply device for a die casting machine.

FIG. 5 is a sectional view of the injection cylinder of FIG. 4;

FIG. 6 is a sectional view showing a configuration of the ladle of FIG. 4;

[Explanation of symbols]

 12 molten metal 13 pouring shaft 14 ladle 30a, 30b plate 31, 38 screw 34 bracket 35 bolt 36 air cylinder 37 operating rod

Claims (3)

(57) [Claims] 1. A weighing molten metal which is attached at a weighing operation position of a ladder to a member for reducing the surface area of the molten metal surface and covers a part of the molten metal surface pumped to the ladder. A method for controlling the amount of hot water supplied to a die casting machine, wherein the variation in the amount of hot water supplied is reduced . 2. A ladle for a die-casting machine hot water supply device, wherein a member for reducing a surface area of a molten metal surface at a measuring operation position is fixed to the ladle. 3. A ladle for a die-casting machine hot water supply apparatus, wherein a member for reducing the surface area of the molten metal surface at the measuring operation position is lowered and installed on the ladle surface only during the measuring operation.