JPH09155530A - Method for casting metal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal casting method which can expect a sure and effective feeder head effect with a pressurizing element and also, can easily and surely draw out the pressurizing element pushed out into the feeder head part. SOLUTION: In the metal casting method which applies the pressure to molten metal in a cavity by pushing the pressurizing element 1 after supplying the molten metal into the cavity 4 in a metallic mold, the feeder head part 5 is arranged at a part except a product part. Further, a gap for forming (casting) a cap-like part is arranged between the inner periphery of the feeder head part 5, and the outer periphery of the pressurizing element 1, and a projecting line 8 is formed along the advancing/retreating direction of the pressurizing element on the inner peripheral surface of the feeder head part or on the outer peripheral surface of the pressurizing element.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is designed so that, after supplying molten metal into a cavity of a mold, a pressurizer is pushed in to compensate for solidification shrinkage of the molten metal to apply pressure to the molten metal in the cavity. The present invention relates to a metal casting method.

[0002]

[Technical background] When casting a product by a die casting method, the molten metal supplied into the cavity of the die rapidly solidifies from the contact surface with the die. It is known that when there is a thick portion, a porosity is likely to occur in the product thick portion, and a shrinkage cavity due to solidification shrinkage is likely to occur in the product thick portion.

[0003]

2. Description of the Related Art Conventionally, as a countermeasure, after supplying molten metal into the cavity of a mold, a pressurizer is pushed into the thick portion of the product to apply pressure to the molten metal in the cavity. However, in reality, it is very difficult to set the timing of pushing the pressurizer, and the molten metal solidifies early from the outer peripheral part that is in contact with the cavity surface, and the pressurizer cannot be pushed in. There were problems such as pushing the indenter too quickly and not expecting much of the effect of the presser.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and it is possible to expect a reliable and effective effect of the pressurizer by the pressurizer, and it is possible to easily press the pressurizer pressed. The present invention also aims to provide a metal casting method that can be reliably pulled out.

[0005]

In the metal casting method of the present invention for achieving the above object, the molten metal is supplied into the cavity of the mold and then the pressurizer is pushed to apply the pressure to the molten metal in the cavity. In the metal casting method described above, a riser portion is provided in a portion other than the product portion, and a gap for forming (casting) a hat-like portion between the inner circumference of the riser portion and the outer circumference of the pressurizer is set, and A ridge is formed on the inner peripheral surface of the riser or the outer peripheral surface of the presser along the advancing / retreating direction of the presser.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. In the embodiment shown in FIGS. 1 to 3, the presser element 1 for applying pressure to the molten metal in the mold cavity is connected to the cavity 4 formed by the fixed mold 2 and the movable mold 3, It is installed so that it can move back and forth. Therefore, in the case of this embodiment, the sprue part of the mold (fixed mold 2, movable mold 3) serves as the riser part 5 provided in a part other than the product part.

In the illustrated embodiment, the riser portion 5, that is, the sprue portion is a block which is constructed so as to be replaceable with respect to the die (fixed die 2, movable die 3). There is.

The pressurizer 1 is slidably inserted into a pressurizing sleeve 6 mounted and fixed to the fixed mold 2 side, and is installed so that the tip end portion thereof can advance and retreat toward the pusher portion 5, that is, the spout portion. ing.

Between the outer circumference of the pressurizer 1 and the inner circumference of the riser section 5, a hat-shaped section S ₂ as shown in FIG. 4 is formed (cast) on a part other than the product section S ₁ . The void 7 is set. That is, the inner diameter of the presser member 5 is made sufficiently larger than the outer diameter of the presser member 1, and when the presser member 1 is pushed into the presser member 5, the outer periphery of the presser member 1 has a hat-like shape. Part S ₂
Is formed (cast).

At this time, the width of the gap 7 is preferably set to about 2 mm to 5 mm. When the width of the void 7 is 2 mm or less, the molten metal in the relevant portion is solidified early and the presser 1
However, if the width of the void 7 is set to 5 mm or more, the thickness (amount) of the hat-shaped portion S ₂ formed (cast) in the relevant portion unnecessarily increases and the material (melting It is not preferable because it wastes metal).

In addition, on the inner peripheral surface of the riser section 5 or the outer peripheral surface of the pressurizer 1, that is, on the inner peripheral surface of the riser section 5 in the illustrated embodiment,
The ridges 8 are formed along the forward / backward direction of the presser 1. The ridge 8 has a groove S ₃ formed in the longitudinal direction, that is, in the advancing / retreating direction of the presser 1, on the outside or inside of the hat-shaped portion S ₂ formed (cast) in the gap 7. is for reducing the embrace with force against pressurizer 1 accompanying the solidification shrinkage of the hat-shaped portion S _2, the width of the gap 7 (2mm~5
mm) or a little smaller than that of the triangular cross-section, and at one or two or more locations (two locations in the illustrated embodiment) over substantially the entire length of the distance that the pressurizer 1 enters. Form. When the ridges 8 are formed at two or more places, the fixed mold 2 and the movable mold 3 are naturally arranged so that the molds can be opened.

During casting, the molds (fixed mold 2, movable mold 3) are closed, and then molten metal is introduced from the molten metal inlet 9 opened in the middle of the pressing sleeve 6 to the pressing sleeve 6.
It is introduced into the inside of the cavity 4 through the runner 10 from the sprue part (the riser part 5) to fill and supply the cavity 4.

After that, when the pressurizer 1 is moved forward and the tip portion thereof is pushed into the molten metal portion 5 (gate portion) to enter, the molten metal in the cavity 4 is pushed into the molten metal portion 5 (gate portion). The molten metal in the cavity is pressurized, and in that state, the molten metal in the cavity 4 is solidified and a product is cast.

On the other hand, at the same time when the product is cast, a gap 7 formed between the outer circumference of the pressurizer 1 and the inner circumference of the riser section 5.
The hat-shaped portion S ₂ is formed (cast) at the portion of the runner portion, the runner portion S ₄ is formed (cast) at the portion of the runner 10, and the molten metal is poured outside (or inside) the hat-shaped portion S _2. The convex groove 8 formed on the inner peripheral surface of the portion 5 (or the outer peripheral surface of the presser 1) forms the concave groove S _{3 in} the longitudinal direction, that is, in the advancing / retracting direction of the presser 1. (See Fig. 4)

Then, the pressurizer 1 is retracted to its original position, the mold (fixed mold 2, movable mold 3) is opened, and the cast product (product portion S ₁ ) is taken out from the cavity 4. Then, the runner portion S ₄ and the hat-shaped portion S ₂ are integrated with the cast product.
Is released from the mold (fixed mold 2, movable mold 3). Hat section S ₂ and the runner portion S ₄ taken out from the mold with the product portion S ₁ is separated from the product portion S ₁ with a press machine or the like.

In the above description, the riser portion 5 is set at the sprue portion following the cavity 4. However, as shown in FIG. 5, the presser 1 is placed near the product portion S _1, preferably the product thick portion. It will be understood from the above description that the present invention can be similarly applied to the one that is installed so as to advance and retreat toward the basin 5 like a basin provided in a part other than the product part.

[0017]

As described above, the metal casting method according to the present invention has the gap for forming (casting) the hat-shaped portion S ₂ between the inner circumference of the riser and the outer circumference of the pressurizer. It becomes possible to hold a sufficient amount of molten metal between the presser part and the presser when pushing into the presser part. That is, even if the outer peripheral portion of the hat-shaped portion S ₂ is solidified early, the inside of the hat-shaped portion S ₂ is in a semi-solidified state, so that there is no fear that the presser will not be able to be pushed into the molten metal portion. Therefore, it is possible to expect a reliable and effective effect of hot water feeding by the presser.

In addition, since the ridges are formed on the inner peripheral surface of the riser or the outer peripheral surface of the presser along the advancing / retracting direction of the presser, there is a gap between the outer periphery of the presser and the inner circumference of the presser. Even if the hat-shaped portion S ₂ formed (cast) by the portion solidifies and shrinks and clings to the outer circumference of the presser, the presser pushed into the feeder part can be easily and surely pulled out. Namely, embraced with force hat-shaped portion S ₂ acting on the outer periphery of the pressurizer (solidification shrinkage force) is mostly determined by the thickness of the hat-shaped portion S _2, the hat portion S ₂ outer or the inner convex Since the concave groove S ₃ is formed along the advancing / retracting direction of the pressurizer with a strip, the embracing force (coagulation contracting force) that actually acts on the pressurizer is relaxed at the concave groove S ₃ , and in some cases Is the concave groove S during solidification shrinkage
_{Even if the} cap ₃ is broken in the longitudinal direction and the hat-shaped portion S ₂ is solidified and shrunk and clings to the outer circumference of the presser, the presser pushed into the riser can be easily and surely pulled out. .

[Brief description of the drawings]

FIG. 1 is a front view showing an example of an apparatus for carrying out the present invention.

FIG. 2 is an enlarged sectional view taken along line (X)-(X) of FIG.

FIG. 3 is an enlarged sectional view taken along line (Y)-(Y) of FIG.

FIG. 4 is a perspective view of a runner portion S ₄ and a hat-shaped portion S ₂ formed (cast) by the method of the present invention.

FIG. 5 is a sectional view for explaining another embodiment of the present invention.

[Explanation of symbols]

1: Pressurizer 2: Fixed type
3: movable type 4: cavity 5: riser part
6: Pressure sleeve 7: Void 8: Convex strip
9: Molten metal inlet 10: Runway S ₁ : Product section S
₂ : Hat-shaped part S ₃ : Recessed groove S ₄ : Runner part

Claims (2)

[Claims] 1. In a metal casting method in which molten metal is supplied into a cavity of a mold and then a pressurizer is pushed to apply pressure to the molten metal in the cavity, a molten metal portion is provided in a portion other than a product portion. At the same time, a metal casting method is characterized in that a gap for forming (casting) a hat-shaped portion is set between the inner circumference of the riser portion and the outer circumference of the presser. 2. The metal casting according to claim 1, wherein a ridge is formed on the inner peripheral surface of the riser portion or the outer peripheral surface of the presser along the advancing / retracting direction of the presser. Law.