JP6989948B2 - Drawing structure of casting dies and casting equipment equipped with it - Google Patents

Description

The present invention relates to the structure of a drawn portion of a die into which a molten metal is injected in casting a metal such as aluminum.

In casting, a molten metal (molten metal) such as aluminum, which is a raw material, is poured into a mold (mold) that combines an upper mold and a lower mold and cooled to produce a casting having a desired shape. Casting includes low pressure casting and die casting. In low-pressure casting, it is formed by filling a mold with molten metal at low pressure and low speed. In die-casting, molten metal is injected at high pressure and high speed, and the molten metal for casting filled in the mold is rapidly solidified, making it possible to mold a large number of shapes with high dimensional accuracy in a short time. I have to.

As described in Patent Document 1, an invention of a molding die that is easy to release when a molten metal is solidified to obtain a molded product is disclosed. In the invention described in Patent Document 1, a sprue for introducing molten metal is narrowed down in the cavity of the mold, and a weir is attached to the narrowed portion. By providing a space for heat insulation inside the weir, the temperature of the molten metal is prevented from dropping sharply, and the hot water solidifies on the mold side and melts under the throttle of the weir. It is adjusted so that it becomes.

Japanese Unexamined Patent Publication No. 2008-80367

However, in the invention described in Patent Document 1, the molten metal is hard to solidify under the narrowed portion of the weir to prevent catching when the molded product is released from the mold, but the narrowed portion of the weir Regular maintenance is required to remove the oxide of the molten metal adhering to the water.

Therefore, an object of the present invention is to provide a casting die having a structure in which the drawn portion is easy to maintain.

In order to solve the above problems, the drawing structure of the casting die of the present invention is placed on a base plate via a heat insulating material, and molten metal is discharged from a hot water supply pipe connected through the base plate. The sprue to be supplied has a lower mold having a throttle portion and an upper mold that can be raised and lowered to form a cavity inside by combining with the lower mold, and the lower mold has the throttle portion in the horizontal direction. It is characterized by having a slide plate to be moved.

Further, in the drawing structure of the casting die, the slide plate has a lower plate that is in contact with the base plate and moves the lower half of the drawing portion, and an upper plate that is in contact with the lower plate and moves the upper half of the drawing portion. It is characterized by having a board.

Further, in the drawing structure of the casting die, the lower plate is characterized in that a heat insulating hole is provided around the drawing hole.

Further, the casting apparatus of the present invention is characterized by having a drawing structure of the casting die.

According to the present invention, it is possible to easily remove the oxide adhering to the drawn portion of the mold or replace the drawn portion. In addition, since the sprue can be closed, it is possible to reduce the oxidation of the molten metal surface held in the hot water supply pipe when maintaining the coating mold in the mold, and the molten metal is discharged from the hot water supply pipe into the mold. It is possible to prevent it from popping out.

It is a front sectional view which shows the overview of the casting apparatus provided with the drawing structure of the casting die of this invention. It is a side sectional view which shows the overview of the casting apparatus provided with the drawing structure of the casting die of this invention. It is an enlarged cross-sectional view which shows the mold of the casting apparatus provided with the drawing structure of the casting mold of this invention. It is a front sectional view and the side view which shows the outline of the drawing structure of the casting die of this invention. It is a front sectional view explaining the drawing structure of the casting die of this invention. It is a perspective view which shows the slide plate of the drawing structure of the casting die of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Those having the same function are designated by the same reference numerals, and the repeated description thereof may be omitted.

First, a casting apparatus provided with a drawing structure of a casting die according to the present invention will be described. FIG. 1 is a front sectional view showing an overview of a casting apparatus provided with a drawing structure of a casting die. FIG. 2 is a side sectional view showing an overview of a casting apparatus provided with a drawing structure of a casting die. FIG. 3 is an enlarged cross-sectional view showing a mold of a casting apparatus provided with a drawing structure of a casting mold.

As shown in FIG. 1, the casting apparatus 100 melts a material made of a metal such as aluminum or an alloy, pours it into a mold, cools it, and processes it into a predetermined shape. It has 120, a mold 200, and the like.

The melting furnace 110 is a furnace for heating a solid material to a melting point or higher using a crucible or the like to form a liquid molten metal 130. The holding furnace 120 is a furnace for heating the molten metal 130 introduced from the melting furnace 110 at a predetermined temperature to keep the liquid state. The mold 200 is a mold for cooling and solidifying the molten metal 130 supplied from the holding furnace 120. In the holding furnace 120, the hydrogen gas or the like taken into the molten metal 130 may be degassed in advance, or the oxide film (slag) or the like formed on the surface of the molten metal 130 may be scraped. I will do it.

As shown in FIG. 2, in the casting apparatus 100, in order to supply the molten metal 130 from the holding furnace 120 to the mold 200, the molten metal 130 is passed through the hot water supply pipe 140 between the holding furnace 120 and the mold 200 by the electromagnetic pump 150. Suck up.

The electromagnetic pump 150 is, for example, an immersion type in which a core (iron core) is arranged inside the hot water supply pipe 140 and an inductor (coil and stator) is arranged outside the hot water supply pipe 140, and the molten metal 130 is transferred from the holding furnace 120. At the same time as sucking up, the molten metal 130 sucked up is held so that the surface 160 of the molten metal has a predetermined height. The amount of the molten metal 130 in the holding furnace 120 and the height of the molten metal level 160 in the hot water supply pipe 140 may be monitored by a liquid level sensor or the like.

The mold 200 has a lower mold 400 fixed on the base plate 210 and an upper mold 300 that can be moved up and down by an elevating mechanism 230. The lower mold 400 and the hot water supply pipe 140 are connected by penetrating the base plate 210. When the elevating plate 240 is lowered by the elevating mechanism 230, the upper die 300 is lowered together with the die base 310.

In the die base 310, the upper die base 310a attached to the lower surface of the elevating plate 240 and the lower die base 310b attached to the upper surface of the upper die 300 are arranged at intervals via a support column or the like, and the upper die base 310a and the lower die base 310 are arranged at intervals. It is assumed that a support plate 320 that can move up and down is arranged between the die bases 310b. Further, it is assumed that the extrusion member 250 penetrating the elevating plate 240 and the upper die base 310a is fixedly fixed, and the push pin 330 penetrating the lower die base 310b and the upper die 300 is attached to the lower surface of the support plate 320. ..

As shown in FIG. 3, the lower surface of the upper mold 300 and the upper surface of the lower mold 400 are recessed in a predetermined shape on the center side, and when the upper mold 300 is lowered and pressed against the lower mold 400, the upper mold 300 and the lower mold 400 are pressed. A cavity 410 is formed between the molds 400. On the verandas of the upper die 300 and the lower die 400, the upper die 300 and the lower die 400 are in close contact with each other with a gap of 0.1 mm or less to prevent hot water leakage. Then, the throttle portion 420 of the lower mold 400 is opened as a sprue, and the molten metal 130 is filled into the cavity 410 from the hot water supply pipe 140 by the electromagnetic pump 150.

When the molten metal 130 is an aluminum alloy, the temperature of the upper mold 300 is set to about 200 to 300 degrees, the temperature of the lower mold 400 is set to about 300 to 400 degrees, solidification is performed from the upper side, and solidification proceeds to the lower molten metal. Make sure that the squeezed portion 420 is solidified. The temperature inside the cavity 410 may be measured with a thermocouple 340 or the like. Since the temperature of the molten metal 130 in the hot water supply pipe 140 is about 600 to 700 degrees, the heat insulating material 220 is arranged on the base plate 210 so that heat is not transferred to the lower mold 400.

When the molten metal in the cavity 410 solidifies and drops to 400 degrees, which is the temperature at which the strength increases, the upper mold 300 is raised. When ascended, the support plate 320 is pressed against the extrusion member 250, and the push pin 330 penetrates the upper mold 300 and protrudes downward. When the molten metal 130 is cooled and solidified, the casting formed into a predetermined shape is released from the upper mold 300.

In the lower mold 400, since the cavity 410 is tapered downward from the inside of the cavity 410 to the throttle portion 420 and is tapered upward from the hot water supply pipe 140 to the throttle portion 420, it is difficult to solidify the lower side of the throttle portion 420 from the inside of the cavity 410. By doing so, it is possible to prevent the coagulated piece from being caught by the throttle portion 420 at the time of mold release.

The casting in the cavity 410 is taken out by mold release, but the solidified pieces of the molten metal 130 adhering to the drawing portion 420 may remain as oxides, so in order to maintain the quality of the casting, deposits and the like may be removed. It needs to be removed regularly.

Next, the drawing structure of the casting die according to the present invention will be described. FIG. 4 is a front sectional view (a) and a side view (b) showing an outline of a drawing structure of a casting die. FIG. 5 is a front sectional view illustrating the drawing structure of the casting die, and shows (a) a state in which the upper plate is slid and moved, and (b) a state in which the upper plate and the lower plate are slid and moved. FIG. 6 is a perspective view showing a slide plate having a drawing structure of a casting die.

As shown in FIG. 4, in the mold 200, the upper mold 300 is aligned with the lower mold 400 placed on the base plate 210 on which the heat insulating material 220 is arranged, and the hot water supply pipe 140 is connected to the throttle portion 420. Make it a state. Before injecting the molten metal 130, the coating mold 430 is applied to the inner wall of the cavity 410.

The coating mold 430 is used to protect the upper mold 300 and the lower mold 400 from the heat of the molten metal 130 to prevent seizure and the like. In addition, ceramic powder such as zirconia and alumina may be attached using water glass.

In addition, maintenance of the drawing section 420 is performed before pouring the molten metal 130 or after taking out the casting, but it takes a lot of time and effort to remove the lower die 400 from the base plate 210 and clean or replace it, so it is drawn from the lower die 400. A slide plate 500 is provided so that only the portion 420 can be laterally moved and taken out in the horizontal direction. The slide plate 500 may be moved in the left-right direction or in the front-back direction.

The slide plate 500 may include a portion of the throttle portion 420 having the narrowest hole diameter. If there is only one slide plate 500, it is very difficult to remove it due to deposits and friction, so it is preferable to stack two slide plates 520 and 510. In addition, 3 or more may be used.

The upper plate 510 and the lower plate 520 are divided into upper and lower parts from the narrowest hole diameter portion of the throttle portion 420, the upper plate 510 slides the upper half of the throttle portion 420, and the lower plate 520 slides the lower half of the throttle portion 420. Slide to move. The thickness of the lower plate 520 is the height from the position in contact with the heat insulating material 220 of the base plate 210 to the position in contact with the upper plate 510, and the upper plate 510 is the same height as the lower plate 520 from the position in contact with the lower plate 520. The thickness should be the thickness.

As shown in FIG. 5 (a), one of the upper plate 510 or the lower plate 520 is first slid and moved from the lower mold 400, and further, as shown in FIG. 5 (b), the lower mold 400 to the upper plate 510 and the lower plate are moved. Slide both plates 520.

The upper plate 510 and the lower plate 520 are removed from the lower mold 400 to perform maintenance such as removing deposits on the throttle portion 420 and replacing the throttle portion 420. Maintenance is very easy because only the upper plate 510 and the lower plate 520 need to be attached and detached.

As shown in FIG. 6, the upper plate 510 has a diaphragm hole 530a that tapers from the upper surface to the lower surface, and the lower plate 520 has a diaphragm hole 530b that tapers from the upper surface to the lower surface. Penetrates. The lower end of the throttle hole 530a of the upper plate 510 and the upper end of the throttle hole 530b of the lower plate 520 have the same hole positions and diameters when the upper plate 510 and the lower plate 520 are overlapped.

A heat insulating hole 540 may be provided around the drawing hole 530 of the lower plate 520 to prevent the molten metal in the drawing hole 530 of the lower plate 520 from solidifying.

A sliding gap is formed between the upper plate 510 and the lower plate 520. The gap between the upper plate 510 and the lower plate 520 may be, for example, about 0.05 to 0.1 mm so that the molten metal 130 does not insert into the gap.

Further, as shown in FIG. 5A, the cavity 410 and the hot water supply pipe 140 are separated by shifting at least one of the slide plates 500 to close the throttle portion 420. The coating mold 430 applied to the inner walls of the upper mold 300 and the lower mold 400 also needs to be maintained regularly (for example, once a week), and it is convenient to close the drawing portion 420.

When the upper mold 300 is raised for maintenance of the coating mold 430, if the throttle portion 420 is blocked, the molten metal 130 held at the predetermined hot water surface 160 in the hot water supply pipe 140 is oxidized. It is suppressed. Further, when the upper mold 300 is raised, the situation where the molten metal 130 pops out from the hot water supply pipe 140 into the cavity 410 is prevented.

In this way, it is possible to easily remove the oxide adhering to the drawn portion of the mold or replace the drawn portion. In addition, since the sprue can be closed, it is possible to reduce the oxidation of the molten metal surface held in the hot water supply pipe when maintaining the coating mold in the mold, and the molten metal is discharged from the hot water supply pipe into the mold. It is possible to prevent it from popping out.

Although examples of the present invention have been described above, the present invention is not limited thereto.

100: Casting equipment 110: Melting furnace 120: Holding furnace 130: Hot metal 140: Hot water supply pipe 150: Electromagnetic pump 160: Hot water surface 200: Mold 210: Base plate 220: Insulation material 230: Elevating mechanism 240: Elevating plate 250: Extrusion Member 300: Upper die 310: Die base 320: Support plate 330: Push pin 340: Thermocouple 400: Lower die 410: Cavity 420: Squeezing part 430: Coating die 500: Slide plate 510: Upper plate 520: Lower plate 530: Squeezing Hole 540: Insulated hole

Claims (3)

A base plate with a hole through which the hot water supply pipe penetrates,
A lower mold placed on the base plate via a heat insulating material,
It has an upper mold that can be raised and lowered and a cavity is formed inside when combined with the lower mold.
The lower mold has a slide plate that can be moved in the horizontal direction on the side of the heat insulating material.
The slide plate includes a throttle portion having a throttle hole for guiding the molten metal from the hot water supply pipe penetrating the base plate to the cavity.
The slide plate includes a lower plate in which the lower half of the throttle portion is formed and can be moved in the horizontal direction, and an upper plate in which the upper half of the throttle portion is formed in contact with the lower plate and can be moved in the horizontal direction. Ori,
The throttle holes are formed in the lower plate and the upper plate, respectively.
The molten metal supplied via the base plate is guided to the cavity through the throttle hole provided in the lower plate of the slide plate and the throttle hole provided in the upper plate of the slide plate. A drawing structure for casting dies, which is characterized by being sewn. The drawing structure of a casting die according to claim 1, wherein a heat insulating hole is provided around the drawing hole formed in the lower plate. A casting apparatus comprising the drawing structure of the casting die according to claim 1 or claim 2 .

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