JPH0890159A - Casting device - Google Patents

Abstract

PURPOSE: To provide a casting device which can prevent defect in a cast product caused by vaporization or carburization of a chaplet consisting of a consumable material. CONSTITUTION: A core 2 has housing space 2a in the inner part thereof and the housing space 2a has an opening hole 2b at the position abutted on the chaplet 3. Carbon compoud, etc., being the consumable material is allowed to flow into the housing space 2a through the opening hole 2b and scarsely remained in a cavity C and therefere, the cast product is cast under the condition of scarsely mixing the carbon compound, etc., into molten metal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a casting device in which a core is held by a kelen made of a fugitive material.

[0002]

2. Description of the Related Art When a hollow-shaped product is obtained by casting, a core provided with a skirting board is used, and this core is generally held in a mold. However, in this case, the cast product has a portion that is not cast by the skirting board. Therefore, depending on the shape of the cast product, the core may be held by the keren. A casting device disclosed in Japanese Patent Laid-Open No. 6-31392 is known as such a keel made of an extinguishing material such as Styrofoam.

When a cast product is cast by this casting apparatus, if the molten metal is injected into the cavity formed by the core and mold held by the keren, the keren made of the fugitive material is vaporized or carbonized by the heat of the molten metal. Then disappears,
It is possible to form a cast product even in the portion where the keren was present.

[0004]

However, in the casting apparatus described in the above publication, the vaporized or carbonized decomposable material is likely to remain in the cavity as it is, so that a gaseous or solid carbon compound or the like is contained in the molten metal. It is easy to cast a cast product while it is mixed. In this case, although the obtained cast product has almost the desired shape, it has defects such as lack of required strength and poor appearance quality due to the inclusion of carbon compounds and the like. May be.

The present invention has been made in view of the above conventional circumstances, and an object of the present invention is to provide a casting apparatus capable of preventing defects in a cast product due to vaporization or carbonization of keren made of a fugitive material. To do.

[0006]

A casting apparatus according to claim 1 is
A mold, and a core forming a cavity with the mold,
In a casting apparatus comprising a dissipative material and a mold holding the core in the mold, the core has a storage space inside, and the storage space is located at a portion in contact with the mold. It is characterized by having an opening.

A casting apparatus according to a second aspect is the casting apparatus according to the first aspect, characterized in that the kelen holds the core in the direction of gravity. The casting apparatus of claim 3 is the casting device of claim 1.
Alternatively, in the casting apparatus described in 2, the storage space is communicated with the outside of the mold via a suction means.

[0008]

When casting a cast product by the casting apparatus according to claim 1, the molten metal is injected into the cavity formed by the core and the mold held by the keren, and the keren made of the fugitive material is heated by the molten metal heat. Evaporates or carbonizes and disappears. At this time, the gaseous or solid carbon compound or the like in which the fugitive material is vaporized or carbonized flows into the storage space inside the core through the opening from the portion where the keren is abutted, and is almost not present in the cavity. Does not remain. Therefore, the cast product is cast in a state in which the carbon compound and the like are hardly mixed in the molten metal.

In the casting apparatus of claim 2, since the core holds the core in the gravity direction, when the carbon compound or the like moves in the direction opposite to the gravity direction due to the specific gravity, it is stored in the storage space inside the core. Easy to flow. For this reason, since the carbon compound and the like are less likely to remain in the cavity, the cast product is cast in a state in which the carbon compound and the like are not further mixed in the molten metal.

In the casting apparatus of claim 3, since the storage space is communicated with the outside of the mold through the suction means, the carbon compound or the like easily flows into the storage space inside the core due to the suction force of the suction means. Even after the inflow, it is discharged from the storage space to the outside of the mold. Therefore, since the carbon compound or the like does not almost completely remain in the cavity, the cast product is cast in a state in which the carbon compound or the like is not mixed in the molten metal almost completely.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. In this casting apparatus, as shown in FIGS. 1 and 2, the lower mold 11 and the upper mold 12 fixed to the lower mold 11 constitute the mold 1. These lower molds 1
The first mold 1 and the upper mold 12 are formed by solidifying sand, and form a cylindrical cavity C together with a core 2 to be described later in order to form a cylindrical cast product. The lower mold 11 and the upper mold 12 are formed with a runner 13 communicating with the cavity C, and the runner 13 is a sprue 1 formed on the upper mold 12.
4 communicates with the outside of the mold 1. Further, the lower mold 11 and the upper mold 12 are formed with a communication passage 15 which communicates with a storage space 2a of the core 2 described later, and the communication passage 15 is communicated with the outside of the mold 1.

In this mold 1, as shown in FIG.
A cylindrical core 2 is stored, and the inside of this core 2 is a storage space 2a. The core 2 has a vent 2b as an opening in the center of the side surface, and this storage space 2a has this vent 2b.
Is communicated with the outside of the core 2. This core 2 is also formed by sticking sand. As shown in FIGS. 1 and 2, the core 2 is held in the mold 1 with the vent 2b directed downward, and the portion contacted with the vent 2b contacted with the kelen 3. There is. The keren 3 is formed of styrofoam as a disintegrating material in a wrapping shape, and is slightly deformed along the mold 1 and the core 2 due to the weight of the core 2 when holding the core 2. . Thus
The core 2 is held in the mold 1, and the gas storage space 2 a of the core 2 is communicated with the outside of the mold 1 by the communication passage 15.
5 is connected to the suction port of the pump 4 as a suction means.

When a cylindrical casting is cast by the casting apparatus constructed as described above, the pump 4 is operated and the molten metal is injected into the cavity C from the sprue 14 through the runner 13. As a result, the keren 3 made of expanded polystyrene is vaporized or carbonized by the heat of the molten metal and disappears. At this time, the carbon compound or the like obtained by vaporizing or carbonizing the expanded polystyrene flows into the storage space 2a inside the core 2 through the vent 2b from the portion where the keren 3 is in contact. In particular,
In this casting apparatus, the keren 3 holds the core 2 in the direction of gravity, and the storage space 2a is connected to the outside of the mold 1 by the communication passage 15 and is connected to the pump 4.
Due to the specific gravity and the suction force of the pump 4, when it moves in the direction opposite to the direction of gravity, it easily flows into the storage space 2a and is discharged from the storage space 2a to the outside of the mold 1 even after the flow. Therefore, the carbon compound or the like does not substantially remain in the cavity C, and the cast product is cast in a state in which the carbon compound or the like is not almost completely mixed in the molten metal. The cast product containing the core 2 becomes a desired cylindrical cast product by ejecting the core 2 while breaking the core 2 from both ends.

Therefore, the cast product obtained by this casting apparatus has the required strength by not containing the carbon compound and the like and has excellent appearance quality. That is, in this casting apparatus, it is possible to prevent defects in the cast product due to vaporization or carbonization of the kerosene 3 made of expanded polystyrene.

[0015]

As described in detail above, the casting product obtained by the casting apparatus according to claim 1 has the structure of claim 1.
In addition to having the desired shape, it has the required strength and is excellent in appearance quality because there is no mixing of carbon compounds and the like. That is, with this casting apparatus, it is possible to prevent defects in the cast product due to vaporization or carbonization of keren made of a fugitive material.

According to the casting apparatus of claim 2,
Since the above constitution is adopted, it is possible to further prevent defects in the cast product due to vaporization or carbonization of keren made of the fugitive material. Furthermore, in the casting apparatus of claim 3,
Since the structure of claim 3 is adopted, it is possible to almost completely prevent defects in the cast product due to vaporization or carbonization of keren made of the fugitive material.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a casting apparatus of an embodiment.

FIG. 2 is a vertical sectional view of the casting apparatus of the embodiment.

FIG. 3 is a perspective view of a core and a skeleton according to the casting apparatus of the embodiment.

[Explanation of symbols]

1 ... Mold (11 ... Lower mold, 12 ... Upper mold) 2 ... Core 2a ... Storage space 2b ... Vent (opening) 3 ... Keren C ... Cavity 15 ... Communication passage 4 ... Pump (suction means)

Claims (3)

[Claims] 1. A casting apparatus comprising a mold, a core forming a cavity together with the mold, and a keren made of a fusible material for holding the core in the mold, wherein the core is inside. A casting apparatus having a storage space, wherein the storage space has an opening at a portion in contact with the kelen. 2. The casting apparatus according to claim 1, wherein the keren holds the core in the gravity direction. 3. The casting apparatus according to claim 1, wherein the storage space communicates with the outside of the mold via a suction means.