JPH06297129A - Molten metal supplying mechanism of low pressure casting machine - Google Patents

Abstract

PURPOSE:To supply the molten metal in a static flow and to stabilize the quality of the molten metal without stopping the casting machine when the molten metal is supplied, without any problem of sealability, without any remarkable fluctuation of the surface of the molten metal at the molten metal holding part, and without complicated control of the air pressure. CONSTITUTION:A molten metal holding part 11 of a low pressure casting machine 10 is connected to a molten metal holding furnace 40 by a piping 25 at the position lower than the surface of the general molten metal of the molten metal holding part, and an opening/closing valve device 30 to switch the flow of the molten metal into the piping and the stop is provided in the piping within the molten metal holding furnace.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molten metal supply mechanism for a low pressure casting machine.

[0002]

2. Description of the Related Art A low-pressure casting machine has been conventionally used for casting a metal molded product such as an aluminum wheel or a cylinder head of an automobile. As shown in FIG. 4 of the accompanying drawings, this low-pressure casting machine stores a molten metal M in a molten metal holding portion (crucible) 51 of a casting machine 50, and pressurizes the molten metal surface with air or an inert gas. The molten metal M is injected and filled into the mold 54 of the metal mold 53 installed on the upper part through the stalk 52 charged in the molten metal M. Then, after the molten metal in the mold 54 is solidified, the pressure is stopped and the pressure is reduced to return the excess molten metal to the holding portion 51 via the stalk 52 again.

In the figure, reference numeral 53A is a fixed side mold, 53B is a movable side mold, 55 is a furnace lid, 56 is a press bed, 57 is a press board, and 59 is a press machine. Further, reference numeral 60 is an air hole, 61 is an air source, 62 is an air control device, 65 is a molten metal supply port, and 66 is a supply chute.

In the conventional low-pressure casting machine 50 of this type, however, when molding is performed for several shots, the molten metal M in the holding portion (crucible) 51 is initially at the maximum level H but becomes at the minimum level L. Therefore, it is necessary to replenish the molten metal M in a predetermined amount.

However, when replenishing the molten metal,
Since the molten metal replenishment port 65 is opened and the chute 66 is used for replenishment, the casting machine must be stopped during this period, which is not only complicated but also inefficient.

Further, the molten metal replenishing port 65 is frequently opened and closed for replenishment, and accordingly, there is a tendency that the sealing property when the molten metal replenishing port is closed becomes unstable.

Further, in the conventional apparatus, since the molten metal surface of the molten metal holding portion 51 is sequentially lowered for each shot and the pressurized volume of air changes accordingly, the air pressure must be corrected for each shot during casting. I have to. Currently, an expensive computer or the like is provided as a control device 62 to correct the air pressure.

Furthermore, when the molten metal is replenished from the molten metal replenishing port 65, there is a problem in the quality of the molten metal such that the molten metal surface is disturbed and a turbulent flow occurs.

[0009]

SUMMARY OF THE INVENTION The present invention has been proposed in order to eliminate all the drawbacks of the conventional mechanism, and does not stop the casting machine even when the molten metal is replenished. There is no problem, and the molten metal surface of the molten metal holder does not fluctuate significantly. Therefore, there is no need to complicate the air pressure. In addition, the molten metal can be replenished in a static flow and the molten metal quality can be stabilized. A molten metal supply mechanism for a casting machine is provided.

[0010]

That is, the present invention is
The molten metal holding part of the low-pressure casting machine and the molten metal holding furnace are connected by a pipe at a position lower than the general molten metal surface of the molten metal holding part, and in the pipe in the molten metal holding furnace, the inflow of molten metal into the pipe and its stop The present invention relates to a molten metal supply mechanism of a low-pressure casting machine, which is provided with an on-off valve device for switching between.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a sectional view showing a molten metal supply mechanism of a low-pressure casting machine according to an embodiment of the present invention, FIG. 2 is an enlarged sectional view of an essential part thereof, and FIG. 3 is a schematic plan view showing an arrangement example of the inventive mechanism. .

As shown in FIG. 1 and FIG. 2 which is a partially enlarged view thereof, in the present invention, the molten metal holding portion 11 of the low pressure casting machine 10 and the molten metal holding furnace 40 are connected by a pipe 25. Regarding the low-pressure casting machine 10, reference numeral 12 is a stalk, 13 is a mold device, 13A is a fixed side mold, 13B is a movable side mold, 14 is a mold, 15 is a furnace lid, 16 is a press bed, and 17 is a press board. , 19 are pressing devices each having a cylinder mechanism. Reference numeral 20 is an air hole, and 21 is an air source. The low-pressure casting machine 10 of this embodiment is substantially the same as the above-mentioned conventional mechanism except for the molten metal supply mechanism.

The molten metal holding portion 11 of the low pressure casting machine 10 has a pipe 25 at a position lower than the general molten metal surface Ms of the molten metal holding portion 11.
Is connected to the molten metal holding furnace 40. Here, the general molten metal surface Ms of the molten metal holding portion 11 means the normal level of the molten metal M of the molten metal holding portion 11 realized by the mechanism of the present invention, and the molten metal M is replenished at a position lower than this, It is a position where molten metal is not replenished at a high position.
Although depending on the size of the molten metal holding portion 11 or the amount of molten metal used for casting shots, the general molten metal surface Ms is a molten metal surface after one shot or several shots after the molten metal M is full.

Further, the molten metal holding furnace 40 is a furnace having a function of keeping the molten metal such as molten aluminum at a constant temperature, and preferably, the melting furnace is integrated, for example, Japanese Patent Publication No. 3-31993. The holding furnace portion of the continuous melting and holding furnace as disclosed in the publication is desirable. Reference numeral F in FIG.
Represents this continuous melting and holding furnace.

The pipe 25 is made of a conventionally known refractory material, and the heater 2 is used as necessary when the distance between the molten metal holding portion 11 of the low pressure casting machine 10 and the molten metal holding furnace 40 is long.
6 are installed.

The pipe 25 is arranged so as to project into the molten metal M of the molten metal holding furnace 40, and the projecting portion 27 is provided with an opening / closing valve device 30 for switching the inflow of the molten metal into the pipe 25 and its stop. As will be understood from the drawing, the on-off valve device 30 is configured so that the valve rod 32 connected to the operating portion of the cylinder device 31 reciprocates to cause the pipe 2 to move.
5, the valve opening 33 provided orthogonally to 5 is opened and closed to switch the inflow of the molten metal M into the pipe 25 and its stop. It should be noted that FIG. 1 shows the open / close valve device 30 in an open state.
Indicates the closed state.

In this mechanism constructed as described above, the valve rod 32 of the on-off valve device 30 is actuated every shot by the casting machine 10 or every several shots so that the molten metal holding furnace 40 moves the molten metal holding portion of the casting machine. The molten metal is supplied to No. 11. If the operation timing and time of the valve rod 32 of the on-off valve device 30 are controlled according to the molding timing by the casting machine, more efficient casting can be performed.

Further, as in the embodiment of FIG. 1, the molten metal holding furnace 40 is used as the holding furnace portion of the continuous melting and holding furnace F in which the melting furnace is integrated, so that the continuously melted molten metal is sequentially cast. The automatic continuous casting can be performed efficiently.

Further, FIG. 3 shows an example in which the holding furnace portion 40 of the continuous melting and holding furnace F is provided with three low pressure casting machines LP1, LP2 and LP3 equipped with the molten metal supply mechanism according to the present invention. In addition, according to the mechanism of the present invention, it is possible to connect to a plurality of casting machines, which contributes to a dramatic improvement in production efficiency.

[0020]

As shown and described above, according to the present invention, the molten metal holding portion of the low pressure casting machine and the molten metal holding furnace are connected by a pipe at a position lower than the general molten metal surface of the molten metal holding portion, Opening / closing valve device provided in the holding furnace Since the molten metal is supplied by the pipe, it is not necessary to stop the casting machine at the time of replenishing the molten metal, and continuous casting is possible.

Further, since the molten metal holding portion of the casting machine is not provided with the molten metal supply port, the problem of sealing property is completely solved.

Further, since the molten metal can be replenished at every shot or every several shots in the casting process at any time,
Unlike the conventional case, the molten metal surface of the molten metal holding portion is not remarkably changed, so that the control of the air pressure during casting does not need to be complicatedly performed by an expensive computer as in the conventional case.

In addition, since the pipe to which the molten metal is supplied is connected by the pipe at a position lower than the general molten metal surface of the molten metal holding portion, the molten metal can be replenished in a static flow without disturbing the molten metal surface and the quality of the molten metal can be improved. The effect of the present invention, such as stabilization, is extremely large.

[Brief description of drawings]

FIG. 1 is a sectional view showing a molten metal supply mechanism of a low pressure casting machine according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of a main part thereof.

FIG. 3 is a schematic plan view showing an arrangement example of the mechanism of the present invention.

FIG. 4 is a sectional view showing a mechanism of a conventional low pressure casting machine.

[Explanation of symbols]

 10 Low Pressure Casting Machine 11 Molten Metal Holding Section 12 Stoke 13 Mold 20 Air Hole 25 Piping 30 Open / Close Valve Device 31 Valve Rod 40 Molten Metal Holding Furnace M Molten Metal F Continuous Melt Holding Furnace

Claims (2)

[Claims] 1. A molten metal holding part of a low-pressure casting machine and a molten metal holding furnace are connected by a pipe at a position lower than a general molten metal surface of the molten metal holding part, and the molten metal to the pipe in the pipe in the molten metal holding furnace is connected. A melt supply mechanism for a low-pressure casting machine, which is provided with an on-off valve device for switching the inflow and stop thereof. 2. The molten metal supply mechanism according to claim 1, wherein the molten metal holding furnace is a holding furnace portion of the continuous melting and holding furnace.