JPH0445261B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a casting apparatus that reduces the pressure of a mold and sucks molten metal.

(Prior Art) The casting method, in which the mold is depressurized and the molten metal is sucked into the cavity, has the advantage of good circulation and easy mechanization because casting can be performed by simply immersing the sprue in the molten metal.

However, with this method, it is necessary to transport the mold above the melting furnace, lower the mold to immerse the sprue in the molten metal, raise the mold after casting, and then transport the mold to a post-processing position. However, the green sand mold normally used here has low strength and is heavy, so if it is moved in a complicated manner as described above, the mold may be damaged, and furthermore, it will cause mechanical strain on the mold. However, there was a natural limit to shortening the casting cycle time, that is, shortening the transportation time other than the casting time.

Moreover, it has become structurally larger, increasing the installation area,
This led to increased costs and increased energy consumption.

(Object of the Invention) In view of the above problems, the present invention aims to shorten the casting cycle time and downsize the apparatus by simplifying the movement of the mold.

(Structure of the Invention) The present invention provides a conveying device for conveying a surface plate having an opening in which a mold can be freely placed and a sprue of the mold can be freely inserted, and a conveying device provided below the conveying surface of the conveying device. a surface plate that is located between the melting furnace and the conveyance device and is provided with a surface plate mounting portion that is approximately the same height as the conveyance surface that forms a part of the conveyance surface of the conveyance device and that is movable up and down; a receiver, and an airtight chamber having an opening and the opening surface of the opening can freely contact the surface plate;
a driving means for moving the airtight chamber up and down and lowering the surface plate support via the airtight chamber to a position where the sprue is immersed in the molten metal in the melting furnace; and a driving means for constantly biasing the surface plate support upward. The present invention is characterized in that it includes a biasing means for energizing the airtight chamber, and a pressure reducing means for reducing the pressure inside the airtight chamber.

As a result, after the mold is carried into the surface plate support by the conveyance device, the drive means is activated to bring the airtight chamber into contact with the surface plate, and when the drive means continues to operate, the surface plate support is lowered. The sprue is immersed in the molten metal, and the driving means is stopped at this point.
When the pressure reduction means is operated, the inside of the airtight chamber becomes a negative pressure state, and the molten metal is sucked into the cavity of the mold in the chamber. After the molten metal solidifies, the operation of the pressure reduction means is stopped and the drive is stopped. When the means is activated to raise the airtight chamber, the surface plate support is raised by the urging means, and the surface plate support stops when the lower surface of the surface plate and the conveyance surface are approximately at the same height. The surface plate on the surface plate holder is carried out of the surface plate holder by the brought-in surface plate and moved onto the conveyance surface.

(Embodiment) The present invention will be described below with reference to embodiments shown in the drawings. In FIGS. 1 and 2, 1 is a conveyance device such as a belt conveyor, and its conveyance surface 2 is connected to an input side 2a. It is separated into an unloading side 2b. Between these carry-in side 2a and carry-out side 2b,
A surface plate support 3 is provided so as to be movable up and down. The surface plate support 3 has a support main body 3a having a U-shaped cross section, and a surface plate mounting portion consisting of a plurality of rollers 4 rotatably attached to the lower part of the support main body 3a. The uppermost portion of the roller 4 is at approximately the same height as the conveying surface 2 of the conveying device 1, and therefore, as will be described later, the surface plate 5 conveyed by the conveying device 1 is kept in a substantially horizontal state. While being held, it moves onto the roller 4 and is placed on the roller 4.

As shown in FIG. 3, a mold 6 is placed on the surface plate 5 conveyed by the conveyance device 1, and a sprue 6a of the mold 6 is placed on the surface plate 5. An opening 5a that can be inserted freely is formed,
Furthermore, an airtight seal section (not shown) is provided around the surface plate 5.

The receiver main body 3a of the surface plate receiver 3 has a sliding member 7
The sliding member 7 is slidably attached to a column 9 erected on a floor 8. A pulley 10 is rotatably attached to the tip of the support 9, a weight 12 is attached to one end of a cable 11 that is wound around the pulley 10, and the other end is connected to the receiving body. 3a, and the cable portion between the pulley 10 and the other end of the cable 11 is wound around a second pulley 13 attached to the tip of the support column 9.

The tip of the support column 9 is bent in the horizontal direction, and the tip of the bent portion 14 reaches above the surface plate support 3. A cylinder 15 is installed in the bent portion 14, and the top surface 1 of the airtight chamber 16 is attached to the tip of the piston rod 15a of the cylinder 15.
6a is installed.

The airtight chamber 16 has an opening at a location opposite to the top surface 16a, and an airtight seal 17 is attached to the periphery of the opening. The airtight seal 17 cooperates with the airtight seal provided on the surface plate 5 to further improve the airtightness of the airtight chamber 16 when the opening of the airtight chamber 16 comes into contact with the surface plate 5. .

The airtight chamber 16 is adapted to be evacuated by a vacuum pump 19 via a conduit 18.

A melting furnace 20 is installed below the surface plate support 3. The melting furnace 20 includes a crucible 20b containing molten metal 20a, a heater 20c that heats the crucible 20b, and a power cable 20d that supplies power to the heater 20c. A moving roller 21 is attached.

Next, the operation of the device related to the upper air configuration will be described. Since the rollers 4 form part of the conveying surface 2 of the conveying device 1, the surface plate 5 conveyed by the conveying device 1 from the carry-in side 2a, when its front end reaches the roller 4, It moves forward on the rollers 4 by the conveying force of the conveying device 1, and when the rear end reaches the roller 4, the conveying device stops.

Next, when the cylinder 15 is actuated and the piston rod 15a is extended, the airtight chamber 16 is lowered to cover the mold 6 and come into contact with the surface plate 5. At this time, the surface plate support 3 is urged upward by the weight 12, so that the airtight chamber 16 and the surface plate 5 are brought into tighter contact.

When the piston rod 15a further extends, the surface plate 5 receives a downward force through the airtight chamber 16, and as a result, the surface plate support 3 resists the biasing force of the weight 12. As the slide member 7 descends, the sliding member 7 also descends along the support column 9. Then, when the sprue 6a is immersed in the molten metal, the operation of the cylinder 15 is stopped, and then the vacuum pump 19 is activated to exhaust the airtight chamber 16. Due to the air permeability of the mold 6 made of green sand, the inside of the cavity is under negative pressure. As a result, the molten metal 20a is sucked into the cavity through the sprue 6a. Note that the vacuum pump 19 may be operated when the airtight chamber 16 comes into contact with the surface plate 5.

Next, after the molten metal filled in the cavity solidifies, the operation of the vacuum pump 19 is stopped and the cylinder 15 is activated to retract the piston rod 15a, so that no pressing force is applied to the surface plate 5. The surface plate support 3 is raised by the urging force of the weight 12, and the sliding member 7 is
When it comes into contact with the restriction plate 22 fixed to the support column 9, the surface plate support 3 stops rising. This position is the position where the uppermost portion of the roller 4 reaches approximately the same height as the conveying surface 2.

Even when the surface plate support 3 stops rising in this way, the cylinder 15 continues to operate, so the airtight chamber 16 continues to rise further and stops at a sufficient distance from the top surface of the mold 6. do.

Next, when the conveyance device 1 is operated, since the rollers 4 form a part of the conveyance surface 2 of the conveyance device 1, the surface plate 5 from the carry-in side 2a is moved to the rear end of the surface plate 5 in the surface plate receiver 3. As a result, the surface plate 5 inside the surface plate support 3 is pushed out of the surface plate support 3 by the surface plate 5 that has been carried in, and the pushed surface plate 5 is It reaches side 2b and is transported.

The weight of the weight 12 is determined depending on the degree of adhesion between the airtight chamber 16 and the surface plate 5, but usually the surface pressure is set to ~1Kg/ ^cm2.
It is set to a certain degree. As the biasing means, a spring, a motor, etc. can be used in addition to a weight. Further, the means for vertically moving the airtight chamber 16 is not limited to the cylinder 15, but may be a vertically moving mechanism using a motor. Further, the surface plate 5 may have a flat plate shape or may have a side end bent upward.

FIG. 4 shows another embodiment of the present invention,
It is characterized by having multiple melting furnaces. That is, a rotatable turntable 23 is installed below the conveyance surface 2, and a plurality of melting furnaces 24 are placed on the table.Each melting furnace 24 is connected to a power supply unit 25 placed in the center. It is designed to heat up.

According to this embodiment, there is always already melted molten metal directly under the surface plate support 3, and therefore the time required for melting is omitted.
As a result, continuous casting becomes possible, and processes such as material charging, melting, and molten metal processing can be carried out outside the conveying surface.

Although a turntable is used in the above example, a plurality of melting furnaces may be arranged on a straight, curved, closed curved, or shuttle-type rail.

(Effects) As is clear from the above, the present invention has a mold that:
The transport device allows horizontal transport, and the mold remains almost horizontal when moving to the surface plate support used to lower the mold, which simplifies the mold movement path. Not only is damage to the mold prevented, but the structure of the device itself is also simplified.

Moreover, since the surface plate mounting part is configured to form a part of the conveyance surface, it is possible to push out the mold after casting by the mold before casting, and as a result, the mold can be carried in before and after casting.・Unloading can be done simultaneously in the shortest possible time, resulting in an increase in the number of castings per hour.

Furthermore, since the mold is raised using a biasing means, the capacity of the driving means can be reduced.

In addition, since the air-tightening of the mold and the start of the lowering operation are simultaneously carried out by the contact surface of the air-tight chamber with respect to the surface plate, the construction is simplified and wasted time is eliminated.

[Brief explanation of drawings]

FIG. 1 is a side view of an apparatus according to the invention, FIG. 2 is a front view of the apparatus, FIG. 3 is a sectional view of a mold, and FIG. 4 is a plan view showing another embodiment of the invention. DESCRIPTION OF SYMBOLS 1... Conveyance device, 2... Conveyance surface, 3... Surface plate support, 4... Roller (surface plate mounting part), 5... Surface plate,
6...Mold, 6a...Gate, 7...Sliding member, 1
0... Pulley (biasing means), 11... Cable, 1
2... Weight, 15... Cylinder, 15a... Piston rod (driving means), 16... Airtight chamber,
19... Vacuum pump (pressure reducing means), 20, 24...
...Melting furnace, 20a... Molten metal.

Claims (1)

[Claims] 1. A conveying device for conveying a surface plate having an opening on which a mold can be freely placed and through which a sprue of the mold can be inserted, a melting furnace provided below the conveying surface of the conveying device, and the conveying device. A surface plate support provided with a surface plate mounting portion located between the surface plate and substantially the same height as the conveyance surface that forms a part of the conveyance surface of the conveyance device and that is movable up and down, and an opening. and an airtight chamber whose opening surface can be brought into contact with the surface plate; the airtight chamber is moved up and down, and the surface plate support is immersed in the molten metal in the melting furnace through the sprue through the airtight chamber. A casting device comprising: a drive means for lowering the platen to a position; a biasing means for constantly biasing the surface plate support upward; and a pressure reduction means for reducing the pressure inside the airtight chamber. .