JPH06182480A - Double solid object and production of resin mold - Google Patents

Abstract

PURPOSE:To provide the double solid objects which can be pulled by low force without cutting cores and the process for production of the resin mold formed by using these double solid objects. CONSTITUTION:Each of the double solid objects 10 is constituted of the core 4 and a sheath 5 and a film consisting of a lubricating material is provided between the sheath and the core. The resin mold having vent holes is produced by inserting many pieces of the double solid objects into a molding surface 9 formed of a shielding film 8 and a granular material 14, then pouring a resin 11 into the mold consisting of the molding surface and curing the resin. The cores 4 of the double solid objects 10 in the resin mold removed from the molding surface after curing of the resin are removed, by which the vent holes are formed in the resin mold. The pulling of the cores 4 is easily and rapidly executed by the small force as the film consisting of the lubricating film is provided between the sheaths 5 and the cores 4. The double solid objects 10 are formed by immersing the double solid objects 10 consisting of the cores and the sheaths into a soln. mixture composed of the lubricating material and a volatile material and penetrating the lubricating material between the cores and the sheaths.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double solid object used for forming a ventilation hole in a resin mold and a method for manufacturing a resin mold using the same, and more particularly, to a vacuum molding method and a general method. The present invention relates to a method for producing a resin mold having a double solid object and a ventilation hole, which is suitable for use in making products using a mold such as casting, synthetic resin mold, and silicone rubber mold.

[0002]

2. Description of the Related Art Generally, as a casting method for casting a product by using a die such as a vacuum molding method, an original die such as a wooden die is used to form a so-called sand die made of particulate matter, and a resin is produced by this die. A method is known in which, after a mold is created, a sand mold is created again using this resin mold, and a final product is cast using this sand mold.

In this method, one surface of a master such as a wooden mold is covered with a shielding film, and the shielding film is suctioned under reduced pressure through a ventilation hole provided in the master, thereby bringing the shielding film into close contact with the master. Then, a predetermined amount of the particulate matter is packed on the shielding film in the frame surrounding the periphery of the shielding film in close contact with the prototype, and then the upper part of the frame, that is, the packed particulate object is further separated. After that, the vacuum suction for the shielding film in the state of being in close contact with the prototype is returned to normal pressure to release the adhesion of the shielding film to the prototype, and further, the inside of the particulate matter is decompressed to be in that state. In this state, the mold is demolded from the particulate matter, and the molding surface is turned upward by reversing the frame filled with the particulate matter that has been demolded to form the molding surface. Inject resin into the molding surface of the object to form a resin mold, Use resin type to form a molding surface of the particulate matter in the same manner as described above steps, by using this forming surface, it is to cast the final product.

In the above-mentioned conventional technique, a plurality of resin molds are formed from one original mold, and these plural resin molds are used to
Since the molding surface of the particulate object for casting the final product can be created, the production efficiency of the product can be improved.

In the above, when the molding surface of the particulate object is formed by using the resin mold, it is necessary to cover the resin mold with a shielding film and suction the resin film under reduced pressure as described above. It is necessary to provide a large number of ventilation holes inside the.

A method of forming a vent hole in a resin mold according to the prior art will be described below with reference to the drawings.

FIG. 5 is a cross-sectional view for explaining the structure of a double solid object forming a vent hole, and FIG. 6 is a view for explaining a method for producing a resin mold. 5 and 6, 4 is a core, 5 is a jacket,
8 is a shielding film, 9 is a forming surface, 10 is a double solid object, 11 is a resin, 12 is a sealing film, 13 is a frame, and 14 is a particulate object.

The molding surface 9 formed on the particulate matter 14 such as silica sand by the shielding film 8 shown in FIG. 6 is prepared by using a prototype such as the above-mentioned wooden mold, and the particulate matter within the frame 13 is formed. 14
Is sealed by the shielding film 8 and the sealing film 12, and the inside of the particulate matter 14 is decompressed and its shape is maintained. Then, for example, a resin 11 such as an epoxy resin is poured into the molding surface 9 and cured to form a resin mold. In order to form the molding surface by the shielding film using this resin mold, the resin mold is formed. It is necessary to form a large number of ventilation holes inside the.

Therefore, normally, a large number of double solid objects 10 formed by the core 4 and the outer jacket 5 as shown in FIG. 5 are planted in the particulate object 14 from the molding surface 9 of FIG. After that, the resin 11 is poured and cured, and by curing the resin 11, the outer surface of the jacket 5 of the double solid object and the resin 11 are joined and integrated, and then the core 4 is pulled out to form a ventilation hole in the resin mold. I am producing.

As the double solid body 10 described above, since an electric wire or the like coated with resin or the like is usually used, the core 4 and the outer cover 5 are in close contact with each other and have friction with each other. ing. This friction increases in proportion to the length of the double solid object 10, and the pulling force of the core 4 also requires a large force. Further, the hole diameter of the vent hole, when the shielding film is adsorbed to the resin mold, if the hole diameter of the contact portion with the shielding film is too large, the shielding film is sucked into the vent hole, causing molding failure,
It is set to 0.8 mmφ to 1.0 mmφ.

As a conventional technique relating to this type of reduced pressure casting method, for example, a technique described in Japanese Patent Laid-Open No. 55-24715 is known.

[0012]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In order to create a through hole that will be a vacuum vent in the resin mold,
After providing a plurality of double solid objects on the molding surface of the resin mold and curing the resin, the core of the double solid object is pulled out. However, this conventional technique has a frictional force because the outer cover of the double solid object is in close contact with the core, and requires a large force in proportion to the length of the double solid object to pull out the core, There is a problem that the labor for this is increased.

This labor increases as the thickness of the resin mold increases and the number of double solid objects increases, and when the above-mentioned frictional force exceeds the cutting limit value of the core, the core is cut off and the core is cut off. There is a problem in that the pores cannot be formed, and it is necessary to open the vent holes by hand.

The object of the present invention is to solve the above-mentioned problems of the prior art, to provide a double solid object which can be pulled out with a low force without cutting the core, and uses the double solid object. It is to provide a method of manufacturing a resin mold.

[0015]

According to the present invention, the above object is to form a double solid object by forming a slippery material on the entire surface around the core between the core and the outer cover. This is achieved by reducing the friction between the two and by embedding such a double solid object in the resin during the making of the resin mold.

According to the present invention, one molding surface of the master mold is covered with a shielding film, and the shielding film is suctioned under reduced pressure to form a molding surface of the shielding film for producing the resin mold, and the resin mold is used. Then, a molding surface for making a final product is created. This resin mold requires a vent hole for suction to bring the shielding film into close contact with the resin mold, and this vent hole forms a double solid object consisting of a core and an outer cover when the resin mold is produced. It is created by embedding it inside.

A large number of the double solid objects are planted on a molding surface for forming a resin mold, and the resin is injected and cured there, so that the solid objects are injected into the molding surface. It is preferable that the core and the outer cover are in close contact with each other so that the resin does not permeate, and the core and the outer cover are in close contact and the core is easily removed. Therefore, the double solid object according to the present invention Is
A film made of a slippery material is formed on the entire surface around the core between the core and the outer cover, and friction between the core and the outer cover is reduced.

[0018]

The air holes of the resin mold are formed at the same time when the resin mold is prepared by providing a double solid object on the molding surface forming the resin mold and pouring the resin into the molding surface. The double solid object has a coating of a lubricant on the entire surface between the core and the outer cover, and the outer cover is adhered by the injected resin and embedded integrally in the resin mold. After that, the core of the double solid object is pulled out, but the frictional resistance between the core and the outer cover can be minimized by the sliding material on the entire surface between the core and the outer cover. It can be easily pulled out without cutting, and the vent hole can be easily formed with less labor and time.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a double solid object and a resin mold using the same according to the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a diagram for explaining a method for producing a double solid object according to an embodiment of the present invention, FIG. 2 is a sectional view showing the structure of a double solid object according to the present invention, and FIGS. It is a figure explaining the formation method of a resin type. In Drawing 1-Drawing 4, 1 is a container, 2 is a container lid, 3 is a mixed solution, 6 is a gap, 7 is a lubricous substance coating, and other symbols are. This is the same as the case of FIGS.

First, a method for producing a double solid object according to an embodiment of the present invention will be described with reference to FIG.

As shown in FIG. 1, a mixed solution 3 of a slippery substance and a volatile solvent for swelling the outer cover of a double solid body is prepared in a container 1, and the slippery substance is volatile in the container. Stir to diffuse mix in solvent. Then, in this stirred mixed solution 3
The double solid object 10 cut into a certain length is immersed in the. This double solid object 10 is formed by a core 4 made of a metal wire or the like and an outer jacket 5 made of a resin or the like that swells with a volatile solvent, and a resin-coated electric wire can be used.

Double solid body 10 immersed in mixed solution 3
Means that the core 5 is not attacked by the solution, and the jacket 5 of the double solid object 10 swells with the lapse of time and the core 4 and the jacket 5 are
A gap 6 is formed between the gap 6 and the gap 6, and the mixed solution 3 containing the slippery substance penetrates into the gap 6.

After the mixed solution 3 has penetrated into the inside of the double solid body 10, the double solid body 10 is taken out from the mixed solution 3 and the solvent is volatilized. As shown in FIG. A coating 7 of a slippery substance is formed on the outer surface of the outer cover 5, and the outer cover 5 contracts due to the evaporation of the solvent and adheres to the core.

After that, when the outer cover 5 contracts and comes into close contact with the core 4, cleaning is performed to remove the slippery substances adhering to the surface of the outer cover 5 of the double solid object 10.

The permeation of the mixed solution 3 containing the slippery substance into the above-mentioned gap 6 depends on the length of the double solid object 10 and the mixing ratio of the slippery substance and the volatile solution for swelling the outer cover. Although depending on the situation, the double solid body 10 may be taken out of the mixed solution 3 and allowed to stand after the mixed solution has sufficiently penetrated into the gap between the core 4 and the jacket 5.

As a result, the volatile solution contained in the jacket 5 of the double solid object 10 evaporates and the jacket 5 contracts,
A slippery substance remains around the core 4 to form the coating 7.

The subsequent cleaning is carried out when the resin mold is prepared.
In consideration of the adhesion between the resin and the jacket 5, this is carried out to remove the slippery material on the outer surface of the double solid object 10, and is to be washed with a new solvent in a short time.

Silicon oil or the like is preferably used as the slippery substance to be contained in the above-mentioned mixed solution, but other petroleum oils, vegetable oils or the like may be used as long as they have lubricity. Good.

Further, in the above description, the slippery substance is permeated between the core and the outer cover of the double solid object which is formed in advance by the core and the outer cover. When creating a real object, a film made of a slippery material may be directly formed between the core and the outer cover. In this case, carbon powder or the like can be used as the slippery material.

Next, a method for producing a resin mold using the above-mentioned double solid object will be described with reference to FIGS.

A resin molding die having a molding surface 9 formed by the particulate matter 14 and the shielding film 8 prepared in the same manner as the prior art described with reference to FIG. 6 is prepared, and as shown in FIG. The outer jacket 5 at the tip of the double solid object 10 described above is peeled off by 4 to 5 mm on the surface 9, and an adhesive is attached to the tip to secure the same from above the shielding film 8. Double solid object 10
The adhesive is attached to the front end of the double solid object 10 for the purpose of fixing and preventing resin penetration.

Then, the resin 11 is injected into the molding surface 9 and cured as shown in FIG. As the resin 11 hardens, the outer surface of the double solid object 10 is adhered to the resin and becomes integral.

Next, the cured resin is removed from the molding surface 9,
The core 4 of the double solid object 10 is pulled out. This core is pulled out
Since a film made of a slippery material is formed on the entire surface between the outer cover 5 and the core 4, the friction is minimized, so that it can be easily performed with a small force without cutting the core 4.

As described above, the resin mold having the ventilation holes is produced.

[0036]

As described above, according to the present invention, when a core of a double solid object is pulled out in order to form a vent hole in a resin mold, friction between the core and the outer cover is reduced. Therefore, it is possible to provide a double solid object that can pull out the core in a short time with a small amount of force, and without using the double solid object, cutting the core and labor. It is possible to reduce the number of the resin molds and to form the resin mold having the vent holes.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a method of creating a double solid object according to an embodiment of the present invention.

FIG. 2 is a sectional view showing the structure of a double solid object according to the present invention.

FIG. 3 is a diagram illustrating a method for forming a resin mold.

FIG. 4 is a diagram illustrating a method for forming a resin mold.

FIG. 5 is a cross-sectional view illustrating the configuration of a prior art double solid object forming a vent.

FIG. 6 is a diagram illustrating a method of producing a resin mold according to a conventional technique.

[Explanation of symbols]

 1 Container 2 Container Lid 3 Mixed Solution 4 Core 5 Outer Cover 6 Gap 7 Lubricant Film 8 Shielding Film 9 Molding Surface 10 Double Solid Object 11 Resin 12 Sealing Film 13 Frame 14 Particle Object

Claims (3)

[Claims] 1. A double solid object used to create a resin-type vent, wherein the double solid object is composed of a core and a jacket, and between the core and the jacket. A double solid object, characterized in that it is provided with a coating made of a slippery material. 2. In a mixed solution of a volatile solvent and a lubricant,
After immersing a double solid object composed of a core and a jacket, swelling the jacket and allowing the mixed solution to penetrate between the core and the jacket, the double solid object from the mixed solution The double solid object is characterized in that a coating made of a slippery material is provided between the core and the outer cover by removing the volatile solvent to remove the volatile solvent. 3. A plurality of the double solid objects according to claim 1 or 2 are planted on a molding surface formed by a shielding film and a particulate matter, and then a resin is molded by the molding surface. After the resin is poured into the mold and the resin is cured, the core of the double solid object integrated with the resin mold removed from the molding surface is pulled out to form a vent hole in the resin mold. Production method.