JPH08142060A - Production of core, core and mold - Google Patents

Abstract

PURPOSE: To easily produce a core within a short time while simply detaching a hollow molded product by putting a small particulate solid material such as sand in a freely deformable bag, a molded object or a core molding jig to mold the same and to mold the hollow molded product high in a completion degree by a mold having a simple structure. CONSTITUTION: A small particulate solid material 2 such as sand is put in a freely deformable bag or molded object to be molded under vibration and vacuum to produce a core 5. Or, a sticking agent is mixed with the solid material 2 to produce the core 5. Further, a mold in which the core 5 is provided is constituted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a core used for processing hollow molded articles of synthetic resin, a method for producing the same, and a molding die.

[0002]

2. Description of the Related Art Conventionally, a molding die in which a core material of a low melting point alloy and a core material of a soluble resin are held in front by a core casting machine, and the formed core is injection molded. The inside of the cavity is filled with molten resin, the cavity is filled with molten resin, and after solidification, it is taken out together with the inside core, and the core inside the core melter is later melted and taken out, and the cleaning process Then, a method for producing a hollow molded article of synthetic resin is carried out.

[0003]

However, in the above low melting point alloy core, a high temperature of 150 ° C. or higher is required to melt the low melting point alloy, and the surrounding environmental pollution is caused by the generation of heavy metal vapor during melting. Becomes Alternatively, even in the core of the soluble resin, the resin must be dissolved by pumping the heated aqueous solution, which requires a large amount of equipment and working time.

[0004]

As a means therefor, a small granular solid body such as sand is put in a deformable bag or a molded body to produce a core by vibrating and vacuuming. Alternatively, a core is manufactured by mixing an adhesive agent into a solid body. Further, it is configured by a molding die in which the core is installed.

[0005]

EXAMPLES Examples of the present invention will be described in detail below. First, in the method of manufacturing a core in the first embodiment, a bag 1 that conforms to the outer dimensions of the core 5 is formed by a film of deformable synthetic rubber or soft vinyl chloride, and several hundreds are contained in the bag 1. A solid body 2 made of dry sand of a mesh is put. Next, the valve 4 is attached to the pulling port 1a of the bag 1, the valve 4a is opened while being placed on the upper surface of the vibrating device 3 while being vibrated, and the solid body 2 is sequentially condensed from below by vacuuming.
After that, the handle 4a of the valve 4 is tightened to form the core 5.

In the core manufacturing method according to the second embodiment, a bag 21 similar to the above is put in a metal core molding tool 6 which is divided into right and left, and then air is sent into the bag 21 to mold the core. It is brought into close contact with the inner surface of the tool 6. Next, put a small granular solid body 22 such as sand in the bag 21, attach the valve 24 to the inlet 21a of the bag 21, and place the valve 24 on the upper surface of the vibrating device 23 to open the valve 24a while applying vibration to evacuate. Due to the solid body 22
Are sequentially condensed from below. After that, the handle 24a of the valve 24 is tightened, the core molding tool 6 is opened to the left and right, and the core 25 is formed.

Next, in the method of manufacturing the core in the third embodiment, a synthetic resin material (blow molded product) having appropriate rigidity is used.
The valve 34 is attached to the outlet 31a of the molded body 31 having the same shape as the core 35, and the solid body 32 similar to the above is put in the internal space, and the highly airtight stopper 31b is inserted into the upper end. Subsequently, the molded body 31 is placed on the upper surface of the vibration device 33, the handle 34a is opened while applying vibration, and the handle 34a is tightened when the solid body 32 and the pillar 31b are sucked downward and condensed by vacuuming. The child 35 is formed.

In the method of manufacturing the core in the fourth embodiment, the molded body 41 provided with the outlet 41a having the same function as described above.
The solid body 42 similar to the above is put in the internal space of the above, and the highly airtight stopper 41b is inserted into the upper end. Subsequently, the molded body 41 is inserted into the core molding tool 46 in which the valve 44 provided with the handle 44a on one of the left and right sides is projected so that the inlet 41a and the valve 44 fit together. After that, the core molding tool 46 is placed on the upper surface of the vibrating device 43, and the handle 44 is vibrated.
a is opened and a vacuum is applied to the solid body 42 and the plug 4
1b is sucked downward and condensed. Finally, handle 4
4a is tightened and the core forming tool 46 is opened to form the core 45.

In the core manufacturing method of the fifth embodiment, a solid core 52 similar to the above is placed in a metal core molding tool 56, which is divided into upper and lower parts and has a lower opening 56a to which a valve 54 is attached. Mix the adhesive in and add. Next, the solid body 52 similar to the above is put into the core molding tool 56 from above, placed on the upper surface of the vibration device 53, the handle 54a is opened while applying vibration, and the solid body 52 is condensed and hardened by vacuuming. Let After that, the handle 54a is closed, the core molding tool 56 is divided into upper and lower parts, and the solid body 52 that has been condensed and hardened is taken out. Then, a synthetic resin paint is applied to the surface of the solid body 52 to form the film 7 and form the core 51.

In the core manufacturing method according to the sixth embodiment, a metal core molding tool 66, which is divided into an upper part and a lower part, is provided with an inlet 66a having a valve 64 attached thereto and an upper part having a small diameter inlet 66b. First, a mold release agent is applied to the inner surface of, and a synthetic resin coating material is applied thereon to form a film 8. Next, the solid body 62 similar to the above is put into the core molding tool 66 from the small-diameter inlet 66b, placed on the upper surface of the vibration device 63, the handle 64a is opened while applying vibration, and the solid body 62 is evacuated. Is condensed and adheres to the film 8. After that, the handle 64a is closed and the core molding tool 66 is divided into upper and lower parts, and the core 61 is taken out. If necessary, in each of the above examples, a solid body may be mixed with an adhesive having an appropriate adhesive force.

Finally, the molding die 9 will be described. The molding die 9 is composed of a fixed die 11 and a movable die 13. A fixed mold 11 provided with a semi-circular fixing portion 11a is fixed to the injection molding machine fixing plate 10 of the injection molding machine so as to fix and tightly attach the core 35 thereto. Next, the movable mold 13 provided with the fixed portion 13a similar to the above is attached to the movable platen 12 of the injection molding machine, and the core 35 is placed on the fixed portion 13a. (See FIG. 7) The core 35 may be left in a vacuumed state. Subsequently, the fixed mold 11 and the movable mold 13 are closed, and the molten resin 1 is injected from the injection molding machine injection cylinder 14.
5 is injected to fill the peripheral space 16 with the molten resin 15.
(Refer to FIG. 8) When the peripheral space 16 is completely filled with the molten resin 15, it is cooled and cured. (See FIG. 9) After curing, the movable mold 13 is moved, and the hollow molded product 18 is taken out by the ejector pin 17. (Figs. 10 and 11
Reference) Handle 34 of core 35 taken out of hollow molded product 18
a is opened, the plug 31b is removed, and the solid body 32 therein is removed. (See FIGS. 12 and 13) Next, the upper and lower parts 3 of the molded body 31 of the hollow molded product 18
Unnecessary parts such as 1c and the sprue 19 are cut off to complete the hollow molded product 18. (See FIGS. 14 and 15) Note that the solid body is not limited to sand and may be any other body as long as it does not have a similar function.

[0012]

According to the present invention, a small granular solid such as sand is put into a deformable bag, a molded body or a core molding tool for molding, so that the core can be easily and surely manufactured. In addition to being carried out, the hollow molded product can be easily removed after processing. Further, the molding die has a simple structure and can form a hollow molded product having a high degree of completion.

[Brief description of drawings]

FIG. 1 is a process drawing of a core manufacturing method according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a forming process in a method for manufacturing a core according to a second embodiment of the present invention.

FIG. 3 is a view showing a forming process in a method for manufacturing a core according to a third embodiment of the present invention.

FIG. 4 is a process drawing of a core manufacturing method according to a fourth embodiment of the present invention.

FIG. 5 is a process drawing of a core manufacturing method according to a fifth embodiment of the present invention.

FIG. 6 is a view showing a forming process in a method for manufacturing a core according to a sixth embodiment of the present invention.

FIG. 7 is a state diagram in which a core is placed in the molding die of the present invention.

FIG. 8 is a diagram showing a state where a molding die of the present invention is filled with molten resin.

FIG. 9 is a state diagram of cooling the molding die of the present invention.

FIG. 10 is a state diagram in which the molding die of the present invention is opened.

FIG. 11 is a state diagram of a hollow molded product taken out of the molding die of the present invention.

FIG. 12 is a view showing a state where a core plug of the hollow molded article of the present invention is taken out.

FIG. 13 is a view showing a state in which a solid body in the core of the hollow molded article of the present invention is taken out.

FIG. 14 is a state diagram in which an unnecessary portion of the molded product of the present invention is removed.

FIG. 15 is a sectional view of the hollow molded article of the present invention.

[Description of sign]

 1 bag 2 solid body 3 vibrating device 4 valve 5 core 6 core molding tool 7 film 8 film 9 molding die

Claims (8)

[Claims] 1. A method of manufacturing a core and a core thereof, wherein a small granular solid such as sand is put in a deformable bag and the core is formed by vibration and vacuuming. 2. The deformable bag according to claim 1 is placed in a core molding tool, air is blown into the bag, and then small solid particles such as sand are placed therein, and vibration and vacuum are applied. A method for manufacturing a core, which comprises forming the core by pulling, and the core. 3. A core manufacturing method comprising filling a small granular solid body such as sand into an inner space of a molded body having the same shape as the core and forming the core by vibrating and vacuuming. And its core. 4. The core according to claim 3 is placed in a core molding tool, and then a small granular solid such as sand is placed in the molding to form a core by vibrating and vacuuming. The manufacturing method of the core and the core. 5. A small granular solid body such as sand is put in a core molding tool, and a film of synthetic resin or the like is formed on the outer periphery of the core formed by vibration and vacuum evacuation. Core manufacturing method and the core. 6. An inner surface of the core molding tool is formed with a film made of a synthetic resin or the like, and small solid particles such as sand are put therein,
A core manufacturing method and a core, wherein the core is formed by vibration and vacuuming. 7. The method for producing a core and the core thereof according to claim 1, wherein an adhesive is mixed in a small granular solid such as sand. 8. The core obtained in each of the above claims is internally provided,
A molding die having a fixing portion for fixing a part of the core in the die.