JPH08197191A - Casting mold forming machine - Google Patents

Abstract

PURPOSE: To form a small-cored hollow core by providing the space part of a head which comes into tight contact with an opening communicating with a die cavity and communicates with the opening with a compressed air supply mechanism and a gas suction mechanism and sucking away uncured molding sand. CONSTITUTION: An upper die 1a and a lower die 1b are set to form the cavity C and a valve 5a is closed by a cylinder 7. A nozzle 5 is pressed to the space part 2c by a cylinder 6 and the molding sand in a metering cup 10a is discharged into the space part 2c'. The circumference of the opening 3 is hermetically closed with a contact piece 2a by a cylinder 4 and a compressed air supply pipe 15a is lowered and is pressed to the hole 8. The molding sand is entrained in the compressed air to pack the cavity when the compressed air is supplied from the nozzle 5 and the compressed air supply pipes 9, 15a. The uncured molding sand in the cavity C is sucked away and the small-cored hollow core is formed when the compressed air is supplied to an ejector 12 by advancing the nozzle 5 and the valve 5a and opening the valve 11b by the cylinders 6, 7 after curing the molding sand on the wall surfaces of the cavity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding machine, and more particularly to a molding machine suitable for producing a hollow core.

[0002]

2. Description of the Related Art Conventionally, in order to manufacture a shell core with a molding machine of this kind, for example, a mixture of sand and a coating agent containing phenol resin as a binder and hexamethylenetetramine as a curing agent has been obtained. The molding sand is filled in the cavity of the heated mold including the upper mold and the lower mold.

Further, in order to manufacture a hollow shell core,
Before the center portion of the core is hardened, the mold is inverted to discharge the uncured molding sand, or the uncured molding sand is sucked and removed.

[0004]

However, in the above conventional mold making machine, when forming a hollow in the mold,
There is the trouble of having to reverse the mold and replace the casting sand supply head with a suction head, and in the case of a relatively small mold, for example, a core of a small core, reverse the mold or replace the head. In the meantime, the center has hardened,
There is a problem that a hollow core cannot be obtained.

Therefore, the present invention has been made in order to solve the above-mentioned drawbacks, and an object of the present invention is to provide a mold making machine in which a hollow core can be easily obtained.

[0006]

In order to achieve the above object, the mold making machine according to the present invention blows molding sand into a cavity provided in a heated mold to form a hardened layer. After that, in a mold making machine for producing a hollow core by discharging uncured molding sand, a space provided with an opening that is hermetically abutted around the opening leading to the cavity provided in the mold A head having a portion, a head moving mechanism for moving an opening of the head in a direction of abutting the opening, and a head moving mechanism for moving the opening away from the opening, and a molding sand for supplying molding sand to the space of the head. A supply mechanism and a compressed air supply mechanism that supplies compressed air to the space of the head when the opening of the head is in contact with the opening, and the opening of the head is in contact with the opening. And To, is characterized by having a suction mechanism for sucking a gas in the space portion of the head. Further, the cavity is characterized by being provided horizontally. Further, the cavity is provided vertically, and the head is brought into contact with the lower portion of the cavity.

[0007]

In the above structure, when compressed air is supplied to the space of the head through the compressed air supply mechanism when the head is in contact with the opening of the mold by the head moving mechanism,
The foundry sand in the space is supplied into the cavity to form a hardened layer. Then, when the gas in the space of the head is sucked by the suction mechanism, the uncured molding sand in the cavity is sucked and removed to manufacture the hollow core.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of a mold making machine according to an embodiment.

The mold 1 is composed of an upper mold 1a and a lower mold 1b, like a well-known mold for manufacturing a shell core, and has an outer shape of the core on the mating surfaces of the two molds 1a and 1b. A cavity C is formed.

The upper mold 1a and the lower mold 1b are provided with burners (not shown), and have a predetermined temperature, that is, a predetermined temperature necessary for hardening the molding sand, for example, 250-2.
It is heated to 90 ° C. Further, the upper mold 1a is provided with a cylinder (not shown), and is configured so that it can be moved up and down as shown by an arrow while being guided by the guide rods R, R ...

The head 2 is constructed so as to come into close contact with the periphery of an opening 3 communicating with a cavity C provided in the mold 1. That is, the head 2 has a space that is open on the side of the opening 3 and is movably provided in the left and right (horizontal) directions by a cylinder 4 that is driven by air or hydraulic pressure, as will be described later, and has moved to the left. At times, it is configured so as to contact the periphery of the opening 3 in a sealed manner.

A contact piece 2a containing a water-cooling pipe (not shown) is provided on the side of the head 2 facing the opening 3, and the contact piece 2a has a position facing the opening 3. And the opening 2b having the same size is provided. Therefore, when the contact piece 2a is brought into contact with the periphery of the opening 3 by the cylinder 4, the space 2c provided inside the head 2 and the cavity C can be airtightly connected to each other. It is possible to effectively prevent the molding sand from closing the opening 2b by being heated when the mold 2 comes into contact with the mold 1.

The capacity of the space portion 2c is determined so as to be compatible with a large number of cores in order to accommodate various kinds of cores. The opening 2 is provided in the space 2c.
A baffle plate 2d is provided, which faces downward on the b side and has a lower end opened. In addition, in the space 2c,
A nozzle 5 directed toward the center of the opening 2b is provided. The nozzle 5 is provided so as to penetrate the baffle plate 2d, and the space 6 on the side opposite to the opening 2b is formed by the cylinder 6.
The nozzle 5 is configured to be movable so that it can be sealed, and a valve 5a that is controlled to open and close by a cylinder 7 is provided in the nozzle 5.

A hole 8 is provided in the upper part of one space 2c 'on the side of the opening 2b divided by the baffle 2d.
A metering mechanism and a compressed air supply pipe, which will be described later, are connected to each other, and a compressed air supply pipe 9 having a valve V1 is connected to the other space 2c ".

The measuring mechanism 10 is composed of a measuring cup 10a having upper and lower portions, which are determined corresponding to the capacity of the cavity C, and a cylinder 10b for horizontally moving the measuring cup 10a. Measuring cup 10a
Is determined to be almost equal to the capacity of the cavity C.

As shown in FIG. 1, when the measuring cup 10a is moved to the right by the cylinder 10b and positioned,
The lower opening H'of the hopper H of the foundry sand and the upper opening 10a 'of the measuring cup 10a are aligned so that the foundry sand in the hopper H can be filled in the measuring cup 10a. Further, this measuring cup 10a, as shown in FIG.
When the cylinder 10b is moved to the left and positioned, the lower opening 10a ″ of the measuring cup 10a coincides with the hole 8 so that the molding sand in the measuring cup 10a can be discharged into the space 2b of the head 2. The lower opening H'of the hopper H can be closed at this position.

A suction pipe 11 having a valve 11b controlled by a cylinder 11a is provided below the space 2c of the head 2.
The suction pipe 11 is connected to the suction side of the ejector 12. Compressed air for driving the ejector 12 is supplied to the ejector 12, and the exhaust side of the ejector 12 is connected to a return sand hopper Ha provided in the hopper H. ing. This return sand hopper H
A discharge pipe 13 having a valve 13b controlled by a cylinder 13a is provided in the lower part of a. The lower end of the discharge pipe 13 is directed to the lower opening H ′ of the hopper H. Therefore, by controlling the opening / closing of the valve 13b, the return sand can be mixed with the new casting sand in the hopper H in a predetermined amount.

Reference numeral 14 in the drawing is a compressed air supply mechanism, which has a cylinder 15 in which the center of the drive shaft is formed hollow to form a compressed air supply pipe 15a. The axial direction of the compressed air supply pipe (driving shaft) 15a is provided vertically, and a lower end of the compressed air supply pipe 15a is provided with an abutting piece 15a 'that abuts around the hole 8. . A valve V2 is provided in the compressed air supply pipe 15a on the side opposite to the side where the contact piece 15a 'is provided, so that compressed air is supplied. Although not shown, the contact piece 15a 'is provided with an adjusting plate for adjusting the aperture ratio.

In order to manufacture a hollow core in the mold making machine having the above-described structure according to this embodiment, first, as shown in FIG. 1, the upper mold 1a and the lower mold 1b are set as shown in FIG. Then, the cavity C is formed. Then, in a state where the head 2 is separated from the mold 1 as shown in FIG. 1, the molding sand is measured by the measuring cup 10a as described above.

Next, as shown in FIG. 3, the cylinder 5 closes the valve 5a and the cylinder 6 brings the nozzle 5 into contact with the space 2c.
By driving b, the molding sand in the measuring cup 10a is discharged through the hole 8 into one space 2c 'of the space 2c. Then, after the contact piece 2a of the head 2 seals the periphery of the opening 3 by driving the cylinder 4 (see the state of FIG. 3), as shown in FIG. 4, the cylinders 6, 7 are driven to drive the valve 5a. , The nozzle 5 is retracted. Further, the cylinder 15 is driven to lower the compressed air supply pipe 15a so that the contact piece 1 is attached to the periphery of the hole 8.
5a 'is brought into contact and sealed, and in this state, compressed air is supplied from the nozzle 5 and the compressed air supply pipes 9 and 15a. As a result, the foundry sand in the space 2c is entrained in the compressed air and filled in the cavity C.

After the molding sand on the wall surface of the cavity C hardens, the cylinders 6 and 7 are driven to move the nozzle 5 and the valve 5a forward to the position shown in FIG.
1a is driven to open the valve 11b, and further the ejector 1
Compressed air is supplied to 2 to start the suction operation. As a result, the interior of the space 2c is in a vacuum state, and the uncured molding sand in the cavity C is removed by suction to form a hollow core. The foundry sand removed by suction is sent to the return sand hopper Ha for reuse.

The hollow core in the cavity C is driven by driving the cylinder 4 to move the head 2 to the right and separating it from the mold 1, and then the upper mold 1a is moved upward and the cavity C is opened and taken out. To be done. Then, the cavity C is formed again, and the manufacturing process of the hollow core is started.

As described above, the mold making machine according to this embodiment can blow the molding sand through the head 2 and remove the uncured molding sand through the head 2, so that the uncured molding can be removed. Sand can be quickly removed, and it becomes possible to form a hollow core even with a core having a small core, and even a core having a diameter of about 5 mm can be formed sufficiently hollow.

In the above embodiment, the cavity C was kept horizontal, the molding sand was fed horizontally, and the uncured molding sand was removed horizontally. However, the casting sand was fed downward. Alternatively, the removal of the uncured molding sand may be directed upwards or downwards while being directed upwards. In particular, when the cavity C is vertical and the head 2 is directed upward so as to contact the lower portion of the cavity C, there is a feature that the thickness of the obtained hollow core can be made uniform. Moreover,
When facing upward as described above, it is possible to omit the measuring mechanism 10 required in the horizontal direction described above, simplify the compression supply mechanism, and further, to remove the uncured molding sand, a valve is provided on the molding sand supply side. There is a structural advantage of not having to provide.

[0025]

According to the mold making machine of the present invention, a head having a space portion having an opening which is hermetically abutted around an opening communicating with a cavity provided in a mold, and an opening of the head. While moving the part in the direction of contacting the opening, a head moving mechanism for moving the part away from the opening, a foundry sand supply mechanism for supplying foundry sand to the space of the head, and the opening of the head. A compressed air supply mechanism that supplies compressed air to the space of the head when the head is in contact with the opening, and a space of the head when the opening of the head is in contact with the opening. Since it is composed of a suction mechanism for sucking the gas, the uncured molding sand can be quickly removed, and in particular, a hollow core core can be formed. Also, when the cavity is horizontal,
The molding sand can be effectively filled and discharged. Furthermore, when the cavity has a vertical shape, the wall thickness of the hollow core can be made uniform.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a mold making machine according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating a moving state of a weighing mechanism portion.

FIG. 3 is an explanatory diagram illustrating a state in which a head is in contact with a mold.

FIG. 4 is an explanatory diagram illustrating a state in which a molding sand is filled in a cavity.

[Explanation of symbols]

1 Mold 1a Upper mold 1b Lower mold 2 Head 2a Abutting piece 2b Opening 2c Space 3 Opening 4, 6, 7, 10b, 11b, 13a, 15 Cylinder 5 Nozzle 8 Hole 9, 15a Compressed air supply pipe 10 Measuring Mechanism 10a Measuring cup 10a 'Upper opening 10a "Lower opening 11 Suction pipe 12 Ejector 13 Discharge pipe 14 Compressed air supply mechanism V1, V2 Valve H Hopper Ha Return sand hopper

Claims (3)

[Claims] 1. A molding sand is blown into a cavity provided in a heated mold to form a hardened layer,
In a mold making machine for producing a hollow core by discharging uncured molding sand, a space portion having an opening portion that is hermetically abutted around an opening leading to the cavity provided in the mold is provided. A head having, a head moving mechanism for moving an opening of the head in a direction of abutting the opening, and a head moving mechanism for moving the opening away from the opening, and a foundry sand supply mechanism for supplying foundry sand to a space portion of the head. A compressed air supply mechanism that supplies compressed air to the space of the head when the opening of the head is in contact with the opening; and the opening of the head is in contact with the opening. Sometimes, a suction mechanism for sucking gas in the space of the head, and a mold making machine. 2. The mold making machine according to claim 1, wherein the cavity is provided horizontally. 3. The mold making machine according to claim 1, wherein the cavity is provided in a vertical shape, and the head is in contact with a lower portion of the cavity.