JPH05237628A - Casting apparatus - Google Patents

Abstract

PURPOSE:To prevent the back flow of cast molten metal liable to occur at the initial stage of casting by top-pouring the pressurized molten metal in the inner part of a lost foam pattern. CONSTITUTION:This casting apparatus is provided with a chamber body 5 engaged with the upper part of a pouring box 4 and being freely movable, a clamping means 7 being freely vertically moval and opened/closed, and a stopper 8 capable of inserting it into the pouring box 4 and supported to the clamping means 7. The clamping means 7 is constituted of a clamping member 7b having one pair of restraining claws 7a for supporting the head part of the stopper 8, a clamping cylinder 7c for opening/closing the restraining claws 7a, and a guide member 7d connected with the clamping member 7b and the clamping cylinder 7c and inserting a piston rod of the clamping cylinder 7c in the inner part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved casting apparatus, and more particularly to a casting apparatus used in the disappearance model casting method.

[0002]

2. Description of the Related Art As a mold used in the disappearance model casting method,
There is a model in which a hanging weir is placed on the sprue of a vanishing model buried in dry sand (for example, Fig. 2 of Japanese Utility Model Publication No. 3-7055).

[0003]

When vanishing model casting is performed using a conventional mold, the vanishing model is thermally decomposed by the heat of the high-temperature molten metal cast through the hanging weir, and part of it is dried sand. Although it is released through the mold to the outside of the mold, especially in the initial stage of casting, the amount of molten metal to be cast is small, and the pressure of the generated decomposition gas tends to be higher than the pressure of the molten metal. Eventually, there was a "blowback phenomenon" in which the casting melt was blown up from the hanging weir, and there was probably a danger in the casting operation. Further, there is a problem that the backflow of the molten metal may cause the molten metal to be poured into the casting mold and run out. Therefore, the present invention has been made in order to solve such a problem, and provides a casting apparatus capable of preventing the backflow of the molten metal which is likely to occur in the initial stage of casting.

[0004]

A casting apparatus according to the present invention comprises a movable chamber body that engages with an upper portion of a weir, a clamp means that can be raised and lowered and can be opened and closed, and can be inserted into the weir. Further, it is provided with a stopper supported by the clamp means.

[0005]

After the stopper is fitted into the retaining weir, the retaining weir is filled with the molten metal. Next, the chamber main body is arranged so as to be engaged with the hanging weir, and after the head of the stopper is supported by the clamp means, the inside of the chamber main body is pressurized to raise the clamp means. The molten metal is drawn out from the hanging weir, and the molten metal is poured into the disappearing model at a high flow rate, and the disappearing model is replaced with the molten metal.

[0006]

EXAMPLES Examples of the present invention are shown in FIGS.
The dry sand 2 is filled therein, the vanishing model 3 is buried in the dry sand 2, and a weir 4 is provided on the dry sand 3. A movable chamber body 5 is provided above the hanging weir 4, and a lower opening is provided in the chamber body 5, and
An air supply pipe 6 is connected to the side wall, and further, a clamp means 7 for supporting a stopper 8 is arranged in the chamber main body 5 so as to be movable up and down. The clamp means 7 is a pair of members for supporting a head of the stopper 8. Clamp member 7b having stop claw 7a
And a clamp cylinder 7c for opening and closing the locking claw 7a,
It is connected to the clamp member 7b and the clamp cylinder 7c,
Moreover, the piston rod of the clamp cylinder 7c is formed of the guide member 7d which is inserted through the inside thereof. A frame 9 is provided on the upper surface of the upper plate 5a of the chamber body 5, and an elevating cylinder 10 for vertically moving the clamp means 7 is attached to the upper part of the frame 9. The elevating cylinder 10 is a clamp cylinder via the piston rod. Lifting cylinder 1 connected with 7c
The clamping means 7 moves up and down by the extension and contraction operations of 0, and the locking claw 7a is opened and closed by the extension and contraction operations of the clamp cylinder 7c, and the guide member 7d moves up and down. It is formed so that the upper plate 5a of the chamber body 5 can be inserted therethrough.

Next, the casting operation will be described. The stopper 8 is inserted into the weir 4 and then the weir 4 is filled with the molten metal. Next, after the chamber body 5 is placed at a predetermined position above the latch weir 4, the lifting cylinder 10 and the clamp cylinder 7c are extended (downward in FIG. 1), and the clamp member 7b is placed in the lower portion of the chamber body 5. At the same time, the engaging claw 7a is opened (FIG. 2 (a)). After that, the chamber body 5 is engaged with the latch weir 4 as shown in FIG. 1, and the chamber body 5 and the latch weir 4 are integrally joined to form a chamber. After that, the clamp cylinder 7c is contracted (upward in FIG. 1), and the locking claw 7a
2 is closed, the clamp member 7b and the stopper 8 are engaged in loose fitting (FIG. 2B), and then compressed air is supplied from the air supply pipe 6 into the chamber body 5 to pressurize the chamber. After that, the lift cylinder 10 is contracted (upward in FIG. 1).
Then, when the locking claw 7a supports the head of the stopper 8 and the lift cylinder 10 subsequently contracts, the guide member 7d and the clamp cylinder 7c rise, and the stopper 8 is pulled out from the latch weir 4 (see FIG. )), The molten metal is top poured into the disappearing model 3 at a high flow rate, the disappearing model 3 is replaced with the molten metal, and the clamp means 7 is held in standby at a predetermined position.
Since the molten metal pressure at the initial stage of pouring is larger than the decomposition gas of the vanishing model 3 generated at the early stage of pouring, backflow of the molten cast metal is unlikely to occur. After that, the pressure inside the chamber main body 5 is released, the chamber main body 5 is moved to a predetermined position, and then the clamp cylinder 7c is extended, so that the locking claw 7a is opened and the stopper 8 is separated from the locking claw 7a. To do. After that, the cast flask 1 is taken out, and the mold is removed to obtain a casting.

In the above-mentioned embodiment, casting was performed in the air, but even if casting is performed under pressure in an inert atmosphere, the same operation as in the above-mentioned embodiment is achieved.

[0009]

EFFECTS OF THE INVENTION According to the present invention, since the molten metal is injected at a high speed and the melt flow is good, it is possible to easily cast a casting free from casting defects such as molten metal breakage and boundary.

[Brief description of drawings]

FIG. 1 is a sectional view of a casting apparatus according to the present invention.

FIG. 2 is an explanatory view showing the operation of the clamp means.

[Explanation of symbols]

 4 latch weir 5 chamber body 7 clamp means 7a locking claw 7b clamp member 7c clamp cylinder 7d guide member 8 stopper

Claims (2)

[Claims] 1. A movable chamber main body that engages with an upper portion of a latch weir, a clamp means that can be raised and lowered and opened and closed, and a stopper that can be fitted into the latch weir and that is supported by the clamp means. A casting device characterized by that. 2. The clamp means includes a clamp member having a pair of locking claws for supporting the head portion of the stopper, a clamp cylinder for opening and closing the locking claws, and a connection between the clamp member and the clamp cylinder, The casting apparatus according to claim 1, wherein the piston rod of the clamp cylinder is formed of a guide member that is inserted therethrough.