JPS60118365A - Casting device - Google Patents

Abstract

PURPOSE:To reduce casting cycle time and the size of a device with a casting device which evacuates the inside of a casting mold and sucks a molten metal by simplifying the movement of the casting mold. CONSTITUTION:A molding board 5 is carried into a casting device by a conveyor 1. The molding board stops upon arriving of the rear end at top of rollers 4. When a piston rod 15a is extended, an airtight chamber 16 descends to cover a casting mold 6 and contacts with the board 5. The board is further depressed and a molding board rest 3 energized upward by a weight 12 descends by overcoming the energizing force until the rest stops when a sprue 6a is dipped into molten metal 20a in a melting furnace. When the inside of the chamber 16 is evacuated by a vacuum pump 19, the molten metal 20a is sucked and filled into the mold 6 by the air permeability of green sand. The pump 19 is stopped and the rod 15a is contracted upon solidifying of the molten metal, then the board 5 is moved upward by the energizing force of the weight 12 and stops at the height at which the uppermost part of the rollers 4 is approximately flush with the conveying plane 2. When the next board 5 is thereupon carried into the machine by the conveyor 1, the board 5 in the rest 3 is carried out.

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 molten metal distribution 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 mechanical strain may be placed on the mold. Therefore, there was naturally a limit to shortening the casting cycle time, that is, shortening the transportation time other than the casting time.

Moreover, they were structurally larger, leading to increased installation space, 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 conveyance 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;
A melting furnace provided below the transfer surface of the transfer device, and a surface plate that forms a part of the transfer surface and includes a surface plate mounting portion that is approximately the same height as the transfer surface and is provided to be movable up and down. Receiving and
an airtight chamber having an opening, and the opening surface of the opening can be brought into contact with the surface plate; By providing a driving means for lowering the chamber to a position where it is immersed in the molten metal in the airtight chamber, a biasing means for constantly biasing the surface plate support upward, and a pressure reducing means for reducing the pressure inside the airtight chamber, After the mold is carried into the surface plate holder by the conveyance device, the driving means is activated to bring it into contact with the surface plate which is an airtight chamber, and when the driving means continues to operate, the surface plate holder is lowered and the sprue is brought into contact with the molten metal. When the driving means is stopped and the pressure reducing means is activated, 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 solidifying, the decompression means is stopped and the drive means is activated to raise the airtight chamber. The surface plate support is raised by the biasing means, and the height of the bottom surface of the surface plate and the conveyance surface is increased. The surface plate holder will stop when the two are almost aligned, and the upper surface plate will be carried out by the brought-in surface plate and moved onto the conveyance surface.

(Embodiment) The present invention will be explained below with reference to the embodiment shown in the drawings. In FIGS. 1 and 2, l is a conveyance device such as a belt conveyor, and the conveyance surface 2 is connected to the carry-in side 2a. It is separated into an unloading side 2b. A surface plate support 3 is provided between the carry-in side 2a and the carry-out side 2b 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 comprising a plurality of rollers 4 rotatably attached to the lower part of the main body 3a. The roller 11. The upper portion is at approximately the same height as the conveying surface 2 of the conveying device 1, and therefore, as described later, the surface plate 5 conveyed by the conveying device 1 moves onto the rollers 4 while maintaining a nearly horizontal state. Then, it is placed on the roller 4.

A third
As shown in the figure, the mold 6 is placed thereon, and the surface plate 5 is formed with an opening 5a through which the sprue 6a of the mold 6 can be freely inserted, and furthermore, the surface plate 5 has The portion is provided with an airtight seal portion (not shown).

The receiver main body 3a of the surface plate receiver 3 is connected to a sliding member 7, and the sliding member 7 is slidably attached to a support 9 erected on a floor 8. At the tip of the pillar 9,
A pulley 10 is rotatably attached, a weight 12 is attached to one end of a cable 11 wound around the pulley 10, and a receiver at the other end is attached to the main body 3a. The cable portion between 10 and the other end of the cable 11 is wrapped 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 a top surface 18a of the airtight chamber 18 is attached to the tip of a piston rod 15a of the cylinder 15.

The airtight chamber 16 has an opening at a location facing the top surface tea, and an airtight seal 17 is attached to the periphery of the opening. The airtight seal 17 seals the surface plate 5 when the opening of the airtight chamber 18 comes into contact with the surface plate 5.
The airtightness of the airtight chamber 16 is further improved by cooperating with the airtight seal provided in the airtight chamber 16.

The airtight chamber 16 is evacuated by a vacuum pump 18 via a conduit 18.

A melting furnace 20 is installed below the surface plate support 3. The melting furnace 20 includes a crucible 2Qb containing molten metal 20a.
The melting furnace 20 has a heater 20C that heats the crucible 20b, and a power cable 20d that supplies power to the heater 20c, and a moving roller 21 is attached to the lower part of the melting furnace 20.

Next, the operation of the device having the above configuration will be described. The surface plate 5 that has been transported from the carry-in side 2a by the transport device 1 is
When the front end reaches the roller 4, the transport device 1 moves forward on the roller 4, and when the rear end reaches the roller 4, the transport device stops.

Next, the cylinder 15 is operated, and the piston rod 15a
When expanded, the airtight chamber 18 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 18 and the surface plate 5 are brought into closer contact with each other.

When the piston rod 15a further extends, the surface plate 5 receives a downward force via the airtight chamber 16, and as a result, the surface plate support 3 resists the biasing force exerted by the weight 12. At the same time, the sliding member 7 also descends along the support column 9. and,
When the sprue 6a is immersed in the molten metal, the operation of the cylinder 15 is stopped, and then the vacuum pump 18 is activated to evacuate the airtight chamber 18. Due to the air permeability of the mold 6 made of green sand, the inside of the cavity becomes under negative pressure. As a result, the molten metal 20a is sucked into the cavity via the sprue θa.

Note that the vacuum pump 18 may be activated 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 18 is stopped and the cylinder 15 is activated to withdraw the piston rod 15a, so that no pressing force is applied to the surface plate 5. The surface plate support 3 has a weight 1
When the sliding member 7 comes into contact with the limiting 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 if the surface plate support 3 stops rising in this way, the cylinder 1
5 continues to operate and therefore the airtight chamber 1B
continues to rise further and stops at a sufficient distance from the top surface of the mold 6.

Next, when the conveyance device 1 is operated, the surface plate 5 from the carry-in side 2a comes into contact with the rear end of the surface plate 5 in the surface plate receiver 3, and as a result, the surface plate 5 in the surface plate receiver 3 is moved forward from the carry-in side. It will be pushed out of the surface plate support 3 by the surface plate 5 that has been
The pushed out surface plate 5 reaches the unloading side 2b and is transported.

The weight of the weight 12 is determined by the degree of adhesion between the airtight chamber IB and the surface plate 5, but it is usually set to a surface pressure of about 1 kg/crn'. Set. 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 1B 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, which is characterized by having a plurality of melting furnaces. That is, a rotatable turntable 23 is installed below the conveyance surface 2, and a plurality of melting furnaces 24 are arranged on the table.
is heated by a power supply unit 25 located in the center.

According to this embodiment, molten metal is always present directly under the surface plate support 3, and therefore the time required for melting is omitted, and as a result, continuous casting is possible. In addition, processes such as charging materials, melting, and processing of molten metal can be performed outside the conveyance surface.

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

(Effects) As is clear from the above, the present invention allows the mold to be transported horizontally by the transport device, and further maintains an almost horizontal state even when transferred to the surface plate support used for lowering the mold. The moving path of the mold is simplified, and as a result, damage to the mold is not only prevented, but also the structure of the apparatus itself is 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 therefore it is possible to carry in and take out the mold before and after casting. can be done at the same time in the shortest possible time,
As a result, the number of castings per hour increases.

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 performed simultaneously 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 the drawing]

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. 1... Conveying device 2... Conveying surface 3... Surface plate support 4... Roller (surface plate mounting part) 5... Surface plate 6... Mold 6a... Sprue 1 12... Weight Li1G... Airtight chamber lθ... Vacuum pump (pressure reducing means) 20.24... Melting furnace 20a... Molten metal patent applicant Toyota Motor Corporation Representative 2

Claims (1)

[Claims] A conveying device for conveying a surface plate having an opening through which a mold can be freely stored and a sprue of the mold can be freely inserted, a melting furnace provided below the conveying surface of the conveying device, and a part of the conveying surface. a surface plate support that is provided with a surface plate mounting portion that is approximately the same height as the conveyance surface that forms the section and is movable up and down; an airtight chamber whose surface can be adjusted freely; 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; 1. A casting apparatus comprising: a biasing device that constantly biases the casting device upward; and a pressure reducing device that reduces the pressure inside the airtight chamber.