JPH0810902A - Formation using special core for forming - Google Patents

Abstract

PURPOSE:To efficiently obtain a formed product, such as a cast product, plastic formed product, ceramic formed product, having excellent quality and wide range of shape without limitation in shape. CONSTITUTION:A special core 1 for forming is composed of a core main body H formed of collapsible material of gravel, etc., in river, sea and mountain and an outer body G made of heat resistant material covering the surface of the core main body of a specific thickness. A forming mold 4 is formed by arranging the core for forming between an upper mold 2 and a lower mold 3, and in the inner part of the forming mold, a cavity having the shape corresponding to the shape of the formed product 6 is formed. The expected formed product can be obtd. by using the special core for forming and the selectable range of the core material is enlarged and also, the improvement of the productivity and the enlargement of the suitable range are realized and further, the forming cost can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding method using a molding special core, and particularly, by molding using a specific molding special core, the selection range of core materials is expanded, Obtaining molded products such as hollow products and undercut products such as cast products, plastic molded products, ceramic molded products, etc. that enable efficient molding of a wide range of molded products without being restricted by the shape. The present invention relates to a molding method using a special molding core capable of molding.

[0002]

2. Description of the Related Art In casting employed as a part of machining, a non-disintegrating core or a disintegrating core is used to form a hollow portion and an undercut portion.

As the former (non-disintegrating core), there is a metal core, but it cannot be used except for those that can be directly punched or deformed, and the range of use is limited to that of a specific shape.

As the latter (disintegrating core), a sand core using foundry sand is generally used. However, since the foundry sand is solidified and molded, a binder or a hardening agent is added to the foundry sand. Was mixed and fired to form a core, but in the conventional method, molding is difficult, and it easily collapses during transportation or molten metal, which is difficult to handle, and at the time of casting. It is difficult to satisfy the reciprocal conditions of pressure resistance and disintegration after casting, and it is difficult to disintegrate because it becomes glassy after casting. There was a problem that it was difficult to remove.

Therefore, in recent years, it has been proposed to apply a mold coating agent to the surface of the sand core. However, the components of the mold coating agent penetrate into the cast product, resulting in cavities and shrinkage in the cast product. In addition to the major problem that defective products are likely to occur due to the adverse effects such as the above-mentioned problems, and the following various defects, the problems could not be solved. (1) Since it is difficult to apply the coating agent, it is necessary to form not only one layer but also a plurality of layers. Therefore, it takes a lot of time and labor to apply the coating agent. Not only is it time consuming and costly, it is also difficult to achieve the initial purpose of applying the mold wash. (2) Since it is difficult to completely remove the binder and the curing agent, which are components of the mold coating agent and sand core, after the molding, the sand baking treatment removes the coating agent, the binder and the curing agent. It requires man-hours, time and cost. (3) Since the sand core is difficult to mold, it requires not only equipment and man-hours, but also the molded sand core is fragile and difficult to handle, and it requires man-hours and yield is poor.
It takes time and money. (4) Sand core requires complicated pressure adjustment to prevent collapse during casting, and complete collapse after casting is difficult. Therefore, heat treatment step, sand drop step, and sand drop inspection are necessary. Therefore, it requires man-hours, time and cost. (5) When casting, a molten metal is inserted between the sand particles of the core, and the components of the sand core permeate into the cast product, causing defective products such as cavities and shrinkage in the cast product. Easy,
Casting yield is poor and productivity is poor. (6) It is difficult to completely remove the core sand after casting, and even if a special operation such as vibration removal is performed, it may adhere to the cast product and cause defects such as wear and damage of the product. (7) Casting of complicated shapes and large castings are difficult or virtually impossible to cast, so the range of application is limited,
There is a problem in design and production. (8) When the sand of the sand core is reused after casting, since the mold coating agent, the binder and the curing agent are contained, the mold coating agent, the binder and the curing agent are completely removed. Is difficult and requires man-hours,
It takes time and money. (9) The sand core has many defects such as difficulty in molding, easy to collapse, and difficult to handle, and it is difficult to satisfy the conflicting conditions of pressure resistance during casting and disintegration after casting. It requires many steps as described below, the yield is low, and it takes time and cost.

That is, the conventional casting method using a sand core requires the following steps. (1) Core molding → (2) Core coating mold → (3) Core drying → (4) Mold formation → (5) Casting by pouring molten metal →
(6) Casting sand removal → (7) Casting sand heat treatment (sand baking) → (8) Casting sand removal inspection → (9) Casting deburring → (10) Finished product.

Further, in a molding method such as injection molding adopted as a part of plastic molding or a molding method such as injection molding adopted as a part of ceramic molding,
Similar to the above casting, there were various problems.

For example, the core must be formed of a specific material having pressure resistance and heat resistance during molding, which makes core molding difficult and costly. There was a problem.

Therefore, in order to solve these problems, the present inventor first used the hollow shape and the undercut shape to form a molded product such as a cast product, a plastic molded product or a ceramic molded product. Forming core, wherein the forming core is formed of a non-sand core, a forming method using the forming core, and the forming core We have proposed a molded product molded using
-064213, Japanese Patent Application No. 4-248503, Japanese Patent Application No. 4-339733, Japanese Patent Application No. 4-339734, Japanese Patent Application No. 4-339735, Japanese Patent Application No. 4-339736, Japanese Patent Application No. 5-47247. Japanese Patent Application No. 5-108857, Japanese Patent Application No. 5-108858, Japanese Patent Application No. 5-200002,
Japanese Patent Application No. 5-208842, Japanese Patent Application No. 5-208843
And Japanese Patent Application No. 5-208844).

[0010] After that, the present inventor continued further research,
A more suitable molding method using a special molding core has been clarified.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems by adopting the following constitution.

That is, for example, in the casting method for obtaining a cast product among the above-mentioned molding methods, (1) the outer body enclosing the core body prevents the components of the core body from penetrating into the molded article. By so doing, it is possible to prevent the cast product from being adversely affected, to prevent the occurrence of defects such as the formation of cavities in the cast product, and to prevent the occurrence of defective cast products, thereby improving the yield and improving the productivity. (2) By avoiding the insertion of molten metal during molding, a molded product is obtained by molding using a special molding core having a smooth surface and excellent strength as compared with a conventional sand core made of foundry sand. ,
To prevent defects such as porosity and shrinkage in a cast product, prevent cast product defects, and enable smooth surface finishing without post-treatment such as machining to improve quality. (3) By obtaining a molded product using a special molding core, it is possible to make the wall thickness thinner than the conventional sand core made of foundry sand, thereby reducing the weight and the cost. (4) By obtaining a molded product using a special molding core, the dimensional accuracy is improved compared to the conventional sand core made of foundry sand, and post-treatment such as machining is unnecessary, and the number of steps is reduced. Try. (5) By using the special molding core, conditions such as pressure resistance and heat resistance required for the core are relaxed, and the selection range of the core material is expanded. (6) By using a special molding core, the material and the amount thereof are selected, and the pressure resistance and heat resistance of the core are adjusted. (7) By using a molding-resistant special core as the core, the molding and handling of the core are facilitated, the man-hours are reduced, and the time and cost are reduced. (8) By using a special molding core that does not use a penetrating component such as a mold coating agent, a binder, a curing agent, etc., it is possible to prevent the core component from penetrating into the cast product. Prevents the occurrence of defects such as shrinkage and shrinkage, and the occurrence of defective cast products, which contributes to improved yield and improved productivity. (9) By using a core that has the conflicting conditions of non-disintegration during molding (heat resistance and pressure resistance) and disintegration after molding (heat disintegration property, solvent disintegration property, etc.), Avoids the occurrence of problems such as molten metal insertion, maintains non-disintegration properties, facilitates heat extinction and discharge after molding, and facilitates the removal of components, prevents adhesion to molded products, and prevents wear of molded products. Prevents the occurrence of problems such as damage and damage. (10) The use of a special molding core facilitates the formation of hollow parts and undercut parts, and by improving the strength of the core, it is possible to cast all shapes and sizes without being restricted by the shape or size. If possible, expand the scope of application. (11) The molding special core does not contain components that are difficult to remove, such as a mold coating agent, a binder, and a curing agent, so that it is easy to disintegrate and remove the core after casting to prevent the occurrence of pollution and to reduce the number of steps. To save time and money. (12) In the molding core, the core body is discharged to the outside of the molded product by melting the outer body, and the collapsible material such as the inorganic material, which is the core body material, is used as the core body material. It is reused by reworking to reduce the material cost.

Further, in the case of a molding method such as injection molding adopted as a part of plastic molding or a molding method using a special molding core such as injection molding adopted as a part of ceramic molding, the above molding is performed. By using the special core for use, a desired molded product can be obtained, and a molded product excellent in quality can be efficiently obtained.

According to the molding method using the above-mentioned molding core, the productivity and the applicable range can be improved even in the case of plastic molding or ceramic molding. As in the case, by using a special molding core, molding of the core is facilitated, molding equipment is simplified, the process is reduced, time and cost can be reduced, and handling Therefore, it is easy to carry and store, and it is possible to solve the conventional problems such as reduction of man-hours such as no need for pressure adjustment during molding and reduction of time and cost.

[0015]

According to the present invention, such an object is used for forming a hollow shape, an undercut shape or the like into a molded product such as a molded product, a plastic molded product or a ceramic molded product. A core for molding which is formed of a collapsible material such as gravel of a river, sea or mountain, and an outer surface for covering the surface (outer surface) of the core. By using a special core for molding consisting of a body and a mold, a mold such as a mold, a plastic mold, or a ceramic mold is formed.
The present invention is achieved by providing a molding method using a special molding core, which is characterized in that a molded product such as a cast product, a plastic molded product, or a ceramic molded product is molded using the molding die.

[0016]

According to the present invention as described above, there are the following actions.

That is, according to the present invention, by using the molding special core as the core, the molding method using the molding special core allows moldings having a wide range of shapes without being restricted in shape. It is possible to efficiently form, and to improve productivity and expand the scope of application, and to improve the quality of molded products. For example, the above-mentioned cast products, plastic molded products, ceramic molded products, etc. Among the molding methods using the molding special core for forming the molded product, the molding method using the molding special core for casting to obtain a cast product has the following effects. (1) The outer body that wraps the core body inside prevents the components of the core body from penetrating into the molded product, thereby preventing adverse effects on the cast product and causing defects such as cavities in the cast product. It is possible to prevent the occurrence of defective products and prevent the production of defective cast products, thereby improving the yield and improving the productivity. (2) By avoiding the insertion of molten metal during molding, a molded product is obtained by molding using a special molding core having a smooth surface and excellent strength as compared with a conventional sand core made of foundry sand. ,
Prevents defects such as porosity and shrinkage in castings, prevents defective castings, and enables smooth surface finish without post-treatment such as machining, thus improving quality. . (3) By obtaining a molded product by using a special molding core, it is possible to make the wall thickness thinner than a conventional sand core made of foundry sand, thereby reducing the weight and the cost. You can (4) By obtaining a molded product using a special molding core, the dimensional accuracy is improved compared to the conventional sand core made of foundry sand, and post-treatment such as machining is unnecessary, and the number of steps is reduced. Can be planned. (5) By using the special molding core, conditions such as pressure resistance and heat resistance required for the core can be relaxed and the selection range of the core material can be expanded. (6) By using a special molding core, the material and the amount thereof can be selected and the pressure resistance and heat resistance of the core can be adjusted. (7) By using the special molding core, molding of the core is facilitated, molding equipment is simplified, the number of steps is reduced, and time and cost can be reduced. (8) Since a special molding core is used, it does not break even if dropped or thrown, so handling is easy, and man-hours such as easy transportation and storage are reduced, and time and cost can be reduced. . (9) Since the molding special core does not contain a penetrating component such as a mold coating agent, a binder, a curing agent, etc., it is possible to prevent the core component from penetrating into the molded product, etc. The occurrence of defects can be prevented, the occurrence of defective products can be prevented, and the yield and productivity can be improved. (10) By using a special molding core, the hollow portion and the undercut portion can be easily formed, and the strength of the core is improved, so that the entire shape and size can be achieved without being restricted by the shape or size. Can be molded, and the range of application can be expanded. (11) By using a core that has the conflicting conditions of non-disintegrating property (heat resistance and pressure resistance) during molding and disintegrating property after molding (heat disintegrating property, solvent disintegrating property, etc.), Avoids problems such as molten metal insertion, maintains non-disintegration properties, facilitates disintegration properties and component removal after molding, prevents adhesion to molded products, and causes defects such as wear and damage to molded products. Occurrence can be prevented. (12) The molding special core does not contain components that are difficult to remove, such as a mold coating agent, a binder, and a curing agent, and has disintegration properties (heat disintegration property, solvent disintegration property, etc.) after molding. As a result, the core can be easily removed, the occurrence of pollution can be prevented, the man-hours can be reduced, and time and cost can be reduced. (13) In the molding core, a collapsible material such as an inorganic material that is a material of the core body that is discharged to the outside of the molded product by melting the outer body is reprocessed as the material of the core body. It can be reused and the material cost can be reduced.

Further, in the case of a molding method such as injection molding adopted as a part of plastic molding, or a molding method such as injection molding adopted as a part of ceramic molding, the special core for molding is used. By using a molding method for molding a molded product, a desired molded product can be obtained, and a molded product excellent in quality can be efficiently obtained.

According to the molding method using the special molding core, productivity can be improved and the range of application can be increased even in the case of plastic molding or ceramic molding. As in the case, by using a special molding core, molding of the core is facilitated, molding equipment is simplified, the process is reduced, time and cost can be reduced, and handling In addition to facilitating transportation and storage, there are various effects such as reduction of man-hours such as no need for pressure adjustment during molding and reduction of time and cost.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings.

1 to 3 show a first embodiment of a molding method using the special molding core of the present invention.

That is, the present invention does not use a sand core made of foundry sand which is generally widely used as a core, and is generally considered to be difficult or unusable for rivers, seas and mountains. , A plastic molding die, or a ceramic by using a molding core made of a core body made of a collapsible material such as, and an outer body that covers the surface (outer surface) of the core body. A molding method using a special molding core, characterized in that a molding die such as a molding die is formed, and a molding product such as a casting, a plastic molding, or a ceramic molding is molded using the molding die. is there.

In the present invention, the special molding core is used to form a mold such as a mold, a plastic mold, or a ceramic mold, and the desired mold is formed using the mold. This is a molding method using a special molding core for obtaining a product.

Then, a molded product using the molding special core is used to mold a molded product such as a cast product, a plastic molded product, or a ceramic molded product.

Therefore, the molding special core used in the present invention has a non-disintegrating property (heat resistance and pressure resistance) at the time of molding and a disintegrating property after molding (heat disintegrating property, solvent disintegrating property, etc.). It is required to meet both conditions.

That is, the special molding core used in the present invention has non-disintegration properties such as heat resistance and pressure resistance during molding of a molded product, and the residual heat of the molded product after molding. Alone or in combination with residual heat and heating, or by heating alone, or by an organic solvent such as normal alkylbenzene (trade name "Nonion" etc.) or other solvent,
It is required to dissolve and remove the outer body so that the core body is in an unrestrained state (free state) and has a disintegrating property so that it can be discharged to the outside of the molded product.

Further, the special molding core is required to have a condition that does not exert a bad influence on the molded product such as generation of a large amount of gas during the molding.

As a result of continued research, the applicant of the present invention, as the molding special core, a core body formed of a collapsible material such as gravel of river, sea or mountain, and the surface of the core body. Since it was determined that a special molding core consisting of an outer body covering the (outer surface) is suitable, here, the core body made of a collapsible material is a gravel, etc. of a river, sea, or mountain. For molding, the outer body has both the non-disintegrating property (heat resistance) during molding and the disintegrating property after molding (heat disintegrating property, solvent disintegrating property, etc.). A molding method using a special core will be described.

That is, the molded special core 1 can be used to form a molded product such as a cast product, a plastic molded product, or a ceramic molded product.

In this embodiment, the desired molded product is obtained by molding in the following steps.

First Step In this embodiment, first, as shown in FIGS. 4 to 6, first, a core body H made of a collapsible material is used.
Is made of shirasu, which is mountain gravel, and the outer body G that covers the surface (outer surface) of the core body H is made of polycarbonate synthetic resin (polycarbonate plastic) that is a thermoplastic synthetic resin. A special core 1 for casting which is a core is constructed.

Second step Then, the special molding core 1 is arranged between the upper mold 2 and the lower mold 3 as shown in FIG. 4 is formed.

For example, when a molded product such as a cast product, a plastic molded product or a ceramic molded product is molded using the molding special core 1, as shown in FIG. The molding special core 1 can be arranged between the upper mold 2 and the lower mold 3 to form the molding die 4 having the cavity 5 in the shape of a molded product.

At this time, as shown in FIGS. 1 and 2, a molding special core including a core body H and an outer body G covering the surface (outer surface) of the core body H. By using 1, it is possible to maintain the pressure resistance when pouring the molding material such as molten metal, to prevent the deformation and maintain the original shape, and to heat the molding material when pouring. It is possible to improve the property and contribute to the molding.

Third Step Next, as best shown in FIGS. 1 and 2, a material corresponding to the material of the molded product is injected into the cavity 5 formed in the molding die 4 under pressure. .

At this time, since the molding special core 1 has a large heat capacity, it has high heat resistance against injection of a molding material such as molten metal, and also has high pressure resistance. Even by the injection, the initial shape can be maintained without thermal deformation or pressure deformation.

Further, the injection temperature of the molding material such as molten metal is
Before reaching the cavity 5 of the molding die 4 such as the above-mentioned mold, the initial temperature (for example, in the case of aluminum melt, about 66
Since the temperature is considerably lower than that of 0 ° C.), the special core 1 for molding, due to its own temperature and heat capacity, has a reflection effect and a temperature even if a high temperature due to injection of a molding material such as the molten metal acts. By the action, the initial shape can be maintained without immediate melting.

Therefore, the molded product 6 such as a cast product having a shape corresponding to the shape of the hollow portion 5 is molded in a state where the original shape is maintained without deforming the special molding core 1. . At this time, in this embodiment, since the heat-resistant outer body G having particularly excellent heat resistance is integrally formed on the surface (outer surface) of the core body H, the molding core 1 during pouring is performed. It has an excellent shape-retaining function, and more reliably holds the initial shape without melting in the molten metal, which can contribute to the molding of the molded product 6 having high dimensional accuracy and excellent quality.

Fourth Step Subsequently, as well shown in FIGS. 2 and 3, the molded product 6 formed as described above is taken out from the molding die 4, thereby completing the molding.

Fifth Step Next, after the molding is completed, the molded product 6 is taken out from the molding die 4, and
With the outer body G melted and removed, the core body H in the unrestrained state (free state) is discharged from the molded product 6 and completely removed, thereby completing the molding.

At this time, the removal of the outer body G1 is basically melted by residual heat of the molded product 6 such as a cast product to be removed and disappeared without leaving a residue, but the shape of the core and the molding of the cast product or the like. Depending on the shape of the product, it melts due to the residual heat of the molded product 6,
Alternatively, it can be dissolved and removed by a solvent, particularly an organic solvent.

That is, the special core 1 for molding is removed,
When the removal of the outer body G by residual heat is insufficient or difficult or impossible, the outer body G can be removed by heating.

In this case, in the present embodiment, the removal of the outer body G can be carried out by the residual heat alone or by using the residual heat and the heating together or by the heating alone.

Further, depending on the shape of the molding special core 1 and the shape of a molded product such as a cast product, in addition to the above-mentioned residual heat or heating, a solvent, particularly an organic solvent, may be used together with residual heat or heating, or may be used alone. It is possible to dissolve and remove the outer body G, particularly the outer body G made of a synthetic resin.

Next, although not shown, the molded product 6
By removing unnecessary portions such as burrs, the finished product 6 can be obtained as well shown in FIG.

In this way, the special molding core 1 can be used to form the desired molded product 6.

At this time, the molding special core 1 contributes to the formation of the intended molded product 6 by maintaining the shape due to its non-disintegrating property (heat resistance and pressure resistance) during molding. After molding, it disintegrates due to its disintegration property (heat disintegration property, solvent disintegration property, etc.) and is removed and eliminated, so that no residue remains and contributes to the molding of molded products with excellent quality such as inner surface smoothing. Can be done.

In the molded product 6 thus formed, the special molding core 1 has a non-disintegrating property (heat resistance and pressure resistance) during molding and a disintegrating property after molding (heat disintegrating property or solvent disintegrating property). Etc.) and is formed from a material that has both conditions,
Moreover, the surface of the molding special core 1 is smoother than the rough surface of the conventional sand core made of foundry sand.
The inner surface such as the hollow portion and the undercut portion formed by the special molding core 1 is formed into a smooth surface without any rough surface.

For this reason, secondary processing such as mechanical processing for smoothing the inner surface is not necessary, and it is possible to prevent the occurrence of defects in the molded product such as wear and damage of the molded product. It is possible to improve the performance of the product using the product.

Further, by using the special molding core of the present invention, a molded product having a hollow portion or undercut, which cannot be conventionally die cast, or a large-sized product, can be obtained. Since die casting has become possible, the degree of freedom in design is improved, so that the performance of the product can be improved, and the cost can be significantly reduced by reducing the weight and improving the productivity.

Further, by preventing adverse effects on the molded product by preventing adverse effects on the molded product and improving dimensional accuracy, it is possible to improve the yield and efficiently obtain a molded product of excellent quality.

The molding special core 1 used in the molding method using the molding special core is as follows.

That is, the molding special core 1 used in the present invention comprises a core body H formed of a collapsible material such as gravel of a river, sea or mountain, and a surface (outer surface) of the core body H. ), And an outer body G that covers Then, the molding special core 1
Is used to form a mold, and the molded product is produced using the mold.

The molding special core 1 used in the present invention has a non-disintegrating property (heat resistance and pressure resistance) at the time of molding and a disintegrating property (heat disintegrating property, solvent disintegrating property, etc.) after molding. It is required to combine both conditions.

Further, the molding special core 1 is required to have a condition that does not exert a bad influence on a molded product such as generation of a large amount of gas during molding.

Further, the outer body G retains its original shape without melting due to the high temperature at the time of molding, wraps the core body H inside to protect it, and the core body H is made of an organic synthetic resin. Even if the core body H generates gas due to the inclusion, etc., it is possible to completely prevent the generation of gas from the special molding core 1 and give adverse effects to the molded product such as generating a large amount of gas during molding. Something that is not done is required.

Therefore, the outer body G satisfies both the above-mentioned conditions and has both the non-disintegration property (heat resistance) at the time of molding and the disintegration property (heat disintegration property, solvent disintegration property, etc.) after molding. It is necessary to be something to do.

As the outer body G which meets this condition, there is a heat resistant outer body made of a heat resistant synthetic resin (heat resistant plastic) or the like. For example, as the heat resistant synthetic resin, a polycarbonate synthetic resin (polycarbonate plastic) or the like is used. There is a thermoplastic synthetic resin (thermoplastic).

In addition to these, heat resistant rubber such as silicone rubber can be used, and any condition is satisfied.

The core body H made of the above-mentioned collapsible material is, for example, an inorganic material such as gravel of river, sea or mountain.

Further, as the core body H satisfying the above conditions, there is a raw molding sand itself containing no binder or hardening agent, or ceramic (new ceramic or old ceramic).

Further, the core body H may be made of a mixture of powdery, granular or lumpy metal. Examples of the metal include iron such as iron oxide and aluminum such as aluminum oxide.

In this embodiment, as shown in FIGS. 4 to 6, the core body H made of a collapsible material is made of shirasu, which is gravel of a mountain.
An outer body G that covers the surface (outer surface) of the core body H is made of a polycarbonate synthetic resin (polycarbonate plastic) that is a thermoplastic synthetic resin, and constitutes a special molding core 1.

Next, a method for forming the molding special core 1 used in the present invention will be described with reference to the accompanying drawings.

4 to 6 show an embodiment of a special molding core used in the present invention.

The molding special core 1 can be formed by various methods.

That is, the first is a method of forming the core body H first, and then the outer body G is formed on the surface (outer surface) of the core body H, and the second is the method of forming the outer body G first. After the formation, the outer body G is formed by filling the inside of the outer body G with a collapsible material such as gravel of river, sea or mountain.

First, a first embodiment of the method for forming the molding special core 1 of the present invention will be described with reference to the drawings.

That is, FIGS. 4 and 5 show a first embodiment of a method for forming the molding special core 1 used in the present invention.

First, as shown well in FIG. 4, shirasu, which is mountain gravel, is used as an inorganic material, and the shirasu is hardened with glue to form a core body H having a predetermined shape.

Next, as shown in FIG. 5, heat resistance is improved by forming a polycarbonate synthetic resin, which is a heat-resistant synthetic resin, with a predetermined thickness on the surface (outer surface) of the core body H. An outer body G composed of a sex outer body is formed.

In this way, it is possible to form the molding special core 1 having a predetermined shape in which the outer body G having heat resistance is formed on the surface (outer surface) of the core body H.

According to the molding special core 1 thus formed, the strength is improved and it becomes difficult to break,
Combined with the ease of handling, it is possible to form regardless of shape and size, expand the range of application, improve productivity, and obtain molded products with excellent quality. It can be obtained efficiently.

Next, a second embodiment of the method for forming the special molding core 1 of the present invention will be described with reference to the drawings.

That is, FIGS. 5 and 6 show a second embodiment of the method for forming the molding special core 1 used in the present invention.

First, as shown in FIG. 6, a polycarbonate synthetic resin, which is a heat-resistant synthetic resin, is formed in a predetermined shape with a predetermined thickness, so that the filling space S is formed in a hollow shape inside. An outer body G made of the heat-resistant outer body is formed.

Next, as well shown in FIG. 5, the filling space S of the outer body G is filled with shirasu, which is gravel of a mountain, as an inorganic material.

In this way, it is possible to form the molding special core 1 having a predetermined shape in which the outer body G having heat resistance is formed on the surface (outer surface) of the core body H.

Further, according to the molding special core 1 formed in this way, similarly to the first embodiment, the strength is improved, the breakage is less likely to occur, and the handling is easy. , It can be formed regardless of shape and size, and it is possible to expand the range of application and improve productivity.
It is possible to efficiently obtain a molded product with excellent quality.

The outer body G is formed on the entire surface of the core body H so as to enclose the core body H as in the above-mentioned embodiment, and although not shown, depending on the shape of the molded product. hand,
It can also be formed on most (or part) of the surface of the core body H.

Further, the molding special core of the present invention is not limited to the above-mentioned embodiment, but can be applied to various shapes using various molding special cores, and the quality of molded products can be improved. The present invention is not limited to the above embodiment,
Many variations are possible.

Further, the molding using the special molding core of the present invention is not limited to the molding method of the above-mentioned embodiment, and specific steps may be added to further improve the quality of the molded product. However, the present invention is not limited to the molding method of the above embodiment, and many modified examples are possible.

Further, the molding special core of the present invention is not limited to the materials and shapes of the above-mentioned embodiments, but can be applied to various shapes using various materials to improve the quality of molded products. You can

That is, the molding special core of this embodiment is
A molded product that has both conditions of non-disintegration during molding (heat resistance and pressure resistance) and disintegration after molding (thermal disintegration property, solvent disintegration property, etc.) and that generates a large amount of gas during molding. However, the outer body used to satisfy this condition may be as follows.

This outer body satisfies the above conditions,
It is necessary that both conditions of non-disintegration during molding (heat resistance) and disintegration after molding (heat disintegration property, solvent disintegration property, etc.) are satisfied, and the core body H is organic. Even if the core body H generates gas due to the inclusion of a synthetic resin, the generation of gas from the special molding core 1 can be completely prevented, and a large amount of gas is generated during molding. It is required that it does not have an adverse effect on the product.

Materials that satisfy this condition include synthetic resins (plastics) and other materials. Among them, the synthetic resins (plastics) include the following.

That is, as a synthetic resin as a material satisfying both of the above conditions, there is, for example, a thermoplastic synthetic resin, which satisfies all of the above conditions, and obtains a molded article which sufficiently satisfies the initial purpose. You can

Further, the most suitable of the thermoplastic synthetic resins (thermoplastics) is the polycarbonate synthetic resin (polycarbonate plastic) of the above-mentioned embodiment, which satisfies all the above conditions. It is possible to obtain a cast product or other molded product that sufficiently satisfies the purpose of the period.

Next to this, there are fluororesins (polyfluoroethylene resins) such as tetrafluoroethylene resin, polyimide resins, polyamide-imide resins and polysulfone resins, which satisfy all the above conditions. ,
It is possible to obtain a cast product or other molded product that satisfies the intended purpose.

Next to this, there are polyamide resin (nylon resin) and polypropylene resin,
Since all of the above conditions are fulfilled, a molded product satisfying the initial purpose can be obtained.

Further, other examples include polyethylene resin and polyester resin (Tetron resin), which have both of the above conditions, and a molded product satisfying the initial purpose can be obtained.

Furthermore, the synthetic resin used for the outer body of the molding special core of this embodiment is not limited to the above-mentioned synthetic resins, and is non-disintegrating (heat resistance) during molding and disintegrating after molding. In addition to satisfying both conditions (heat disintegrating property, solvent disintegrating property, etc.), even if the core body H contains an organic synthetic resin and the core body H generates gas, it is special for molding. As long as it can completely prevent the generation of gas from the core 1 and does not give a bad influence to the molded product such as generating a large amount of gas at the time of molding, a thermoplastic synthetic resin or a thermosetting resin other than those in the above examples Naturally, a synthetic resin and other synthetic resins (plastics) can also be used, and the same effects as those of the above-mentioned embodiment can be obtained.

Further, the material used for the outer body of the molding special core of this embodiment is not limited to the above synthetic resin,
In addition to satisfying both conditions of non-disintegration during molding (heat resistance) and disintegration after molding (heat disintegration, solvent disintegration, etc.), the core body H contains an organic synthetic resin, etc. Even if the core body H generates gas due to the
As long as it can completely prevent the generation of gas from the product and does not adversely affect the molded product such as generating a large amount of gas during molding, heat-resistant synthetic rubber, silicon rubber, fluorine rubber, or other rubber. Needless to say, it is also possible to use heat-resistant rubber such as silicone rubber, and the same effects as those in the above-mentioned embodiment can be obtained.

Further, the material used for the outer body of the molding special core of this embodiment is not limited to the above synthetic resin (plastic) or rubber as long as it satisfies the above conditions, and tin,
Low melting metals such as lead and antimony, ceramics, and other single materials can be used, as well as FRR (fiber reinforced rubber), FRP (fiber reinforced plastic), GFRP (glass fiber reinforced plastic) and other composite materials. The outer body using various materials is conceivable, and the same effect as that of the above-mentioned embodiment can be obtained.

Further, the molding special core used in the present invention is not limited to the materials and shapes of the above-mentioned embodiments, but can be applied to various shapes using various materials,
It is possible to improve the quality of molded products such as castings,
Many modifications are conceivable, and the same effect as each of the above embodiments can be obtained.

The removal of the outer body G1 is basically dissolved and removed by the residual heat of the molded product 6 such as a cast product.
Depending on the shape of the core or the shape of a molded product such as a cast product, it can be dissolved by the residual heat of the molded product 6, or can be dissolved and removed by heating or a solvent, particularly an organic solvent.

That is, the special core 1 for molding is removed,
When the removal of the outer body G by residual heat is insufficient or difficult or impossible, the outer body G can be removed by heating.

In this case, in the present embodiment, the removal of the outer body G can be performed by the residual heat alone, the residual heat and the heating in combination, or the heating alone.

Further, depending on the shape of the molding special core 1 or the shape of a molded product such as a cast product, in addition to the above-mentioned residual heat or heating, a solvent, particularly an organic solvent, may be used in combination with the residual heat or heating, or independently. It is possible to dissolve and remove the outer body G, particularly the outer body G made of a synthetic resin.

As the solvent, when the outer body G is a polycarbonate synthetic resin (polycarbonate plastic) among thermoplastic synthetic resins (thermoplastics), normal alkylbenzene (trade name "Nonion") is used.
Etc.) was sufficiently satisfactory in terms of function and cost, and there was no problem in actual use.

In addition to the above, examples of the polycarbonate synthetic resin solvent include the following.

For example, tetrachloroethane, methylene chloride, chloroform, 1,1,2 trichloroethane, etc. were able to obtain the same effect.

The solvent of the present invention is not limited to the solvent of the above-mentioned examples as long as it can dissolve the external body, and it is needless to say that various solvents can be used, and with the residual heat or heating, If it is carried out independently, the same effect as in the above embodiment can be exhibited.

Next, a molding method using the molding special core of the present invention, that is, a method of molding a molded product such as a cast product, a plastic molded product or a ceramic molded product using the molding special core of the present invention. Among them, a casting method for casting a cast product using a special casting core that is a special molding core will be described.

Here, there will be described a case where the casting is carried out and one of the cases is the die casting.

That is, in the present embodiment, the intended cast product is obtained by casting in the following steps.

First Step In this example, first, as shown in FIGS. 4 to 6, the core body H made of a collapsible material.
Is made of shirasu, which is mountain gravel, and the outer body G that covers the surface (outer surface) of the core body H is made of polycarbonate synthetic resin (polycarbonate plastic) that is a thermoplastic synthetic resin. A special core 1 for casting which is a core is constructed.

Second Step Then, the casting special core 1 is arranged between the upper mold 2 and the lower mold 3 to form the mold 4 as well shown in FIG. .

At this time, as best shown in FIGS. 1 and 2, a special core for casting comprising a core body H and an outer body G covering the surface (outer surface) of the core body H. By using 1, it is possible to maintain the pressure resistance when pouring the molten metal, prevent deformation and maintain the original shape, and improve the heat resistance when pouring the molten metal. It can contribute to casting.

Third Step Next, as best shown in FIGS. 1 and 2, a molten metal such as an aluminum molten metal is poured into the cavity 5 formed in the mold 4 in accordance with the die cast product. .

At this time, since the molding special core 1 has a large heat capacity, it has a high heat resistance to the molten metal and a high pressure resistance. The initial shape can be retained without doing so.

Furthermore, since the temperature of the molten metal injected is considerably lower than the initial temperature (for example, about 660 ° C. for aluminum molten metal) by the time it reaches the cavity 5 of the mold 4, the special core 1 for molding is used. Depends on its own temperature and heat capacity
Even if the high temperature of the molten metal acts, the initial shape can be maintained without immediate melting due to the reflection effect and the temperature effect.
Therefore, the casting 6 having a shape corresponding to the shape of the cavity 5 is cast in a state where the original shape is maintained without deforming the special molding core 1.

Fourth Step Subsequently, as well shown in FIG. 3, the cast product 6 formed as described above is taken out from the mold 4,
Finish die casting.

Fifth Step Further, as well shown in FIG.
Is removed from the mold 4, and in a state where the outer body G is dissolved and removed by residual heat or the like, the core body H in the unrestrained state (free state) is discharged from the casting 6 and completely removed. Thus, the casting is completed.

Further, although not shown, unnecessary parts such as burrs of the cast product 6 can be removed to obtain a finished product.

The casting 6 thus formed has excellent appearance quality and functional quality because defects such as cavities are prevented from occurring.

Therefore, compared with the conventional casting method which required the following 10 steps, only 5 steps are required and 5 steps are omitted.

That is, the conventional method using the sand core is as follows.
It looks like this: (1) Core molding → (2) Core coating mold → (3) Core drying → (4) Mold formation → (5) Casting by pouring molten metal →
(6) Casting sand removal → (7) Casting sand heat treatment (sand baking) → (8) Casting sand removal inspection → (9) Casting deburring → (10) Finished product.

As described above, by using the molding method using the special molding core of the present invention, it is possible to prevent defects such as wear and damage of the cast product 6 and to improve the quality. Since the occurrence of defects such as porosity is prevented and the appearance quality and functional quality are excellent, the yield is also improved, and the man-hours are greatly reduced to efficiently obtain a cast product 6 with excellent quality. Because you will be able to
You can save time and money and improve productivity.

The molding method using the special molding core of the present invention is not limited to die casting as one of the casting methods shown in the above embodiments, but a specific step is added to the die casting method. Therefore, the quality of the cast product can be further improved, and the present invention is not limited to the above-described embodiment, and many modified examples are possible.

Further, in the above embodiment, the case where a casting product is obtained by performing die casting casting as one of the casting methods using the casting special core which is the molding special core is described. The molding special core of the invention is not limited to the die-cast casting, but can be of course applied to a sand type gravity casting method, a die gravity casting method, a low pressure casting method or a precision casting method, and other casting methods. Therefore, it is possible to obtain the same excellent effect as that of the above-described embodiment.

In this case, the effect of the present invention is particularly great in the gravity casting method.

That is, in the gravity casting method, the residence time of the molten metal during casting is longer than in other casting methods,
Since the molten metal is in contact with the core for a long time and the temperature of the molten metal is relatively high, the core is required to have non-disintegrating property (heat resistance and pressure resistance). By molding a molded product using a core, a sand core using a conventional foundry sand or a special molding core made of only synthetic resin, which the present inventor previously invented and applied for, is used. Compared with the case, since the specific heat becomes large and the heat capacity becomes large, the temperature rise of the resin core 1 when pouring the molten metal becomes relatively small, the heat resistance to the molten metal is significantly improved, and the pressure resistance is also improved. Since it is remarkably improved, even when pouring a molten metal with a long residence time during casting, the initial shape can be maintained without thermal deformation or pressure deformation, and a wide range of excellent shape without restriction of shape. It is possible to contribute to the formation of the intended casting 6 which is the above-mentioned molded article.

At this time, referring to FIGS. 1 to 4, when a special casting core, which is the special molding core of the present invention, is used to obtain a casting product, a casting product is obtained by gravity casting. The case of obtaining will be described.

That is, in this embodiment, description will be given of a case where a casting product is obtained by a gravity casting method using a casting special core as a molding special core.

In this embodiment, as shown in FIGS. 4 to 6, the core body H made of a collapsible material is made of shirasu which is gravel of a mountain.
An outer body G that covers the surface (outer surface) of the core body H is made of a polycarbonate synthetic resin (polycarbonate plastic) that is a thermoplastic synthetic resin, and constitutes a special casting core 1 that is a special molding core. are doing.

Using the casting special core 1 which is the molding special core, a cast product can be formed by the gravity casting method.

For example, as best shown in FIG.
The casting special core 1 is disposed between the upper mold 2 and the lower mold 3 to form a mold 4 having a cavity 5.

Next, as best shown in FIGS. 1 and 2, a molten metal such as an aluminum molten metal is poured into the cavity 5 formed in the mold 4 depending on the material of the cast product.

At this time. Similar to the above-mentioned examples, the special core 1 for casting has a large specific heat and a large heat capacity, so that the temperature rise when pouring the molten metal is relatively small, and the heat resistance to the molten metal is significantly improved. Since the pressure resistance is remarkably improved, the initial shape can be maintained without being deformed by heat or pressure even when the molten metal having a long residence time during casting is poured, and the intended casting 6 is formed. Can contribute to.

That is, the temperature of the molten metal is considerably lower than the initial temperature (for example, about 750 ° C. in the case of aluminum molten metal) by the time it reaches the cavity 5 of the mold 4, so that the casting Even if the molten metal acts due to its own temperature and heat capacity, the special core 1 for use can retain its initial shape without being immediately melted due to the reflecting action and the temperature action.

Therefore, it is possible to obtain a cast product 6 having a shape corresponding to the shape of the cavity 5 while maintaining the original shape without deforming the special molding core 1.

Next, after the casting is completed, the cast product 6 is taken out from the mold 4, and the core body H in the unconstrained state (free state) is cast with the outer body G dissolved and removed. By discharging from 6 and completely removing it, casting is completed.

Further, as best shown in FIG.
Since the casting is completed by removing the casting 6 from the mold 4 and removing the special molding core 1, the unnecessary portion such as burrs of the casting 6 is removed, and the casting is a desired finished product. 6 is formed.

The cast product 6 thus formed is a cast product having excellent appearance quality and functional quality in which defects such as cavities and shrinkage are prevented.

Therefore, by casting using a sand core made of foundry sand that has been widely used as a conventional core, the man-hours are greatly reduced and the quality is improved as compared with the case of obtaining a cast product. An excellent cast product can be efficiently obtained.

As described above, even in the gravity casting method, the special molding core 1 contributes to the formation of the intended casting 6 by maintaining its shape during casting, and after the casting, The outer body G is melted and completely removed by the residual heat of 6 and the core body H in a non-restrained state (free state) in a state where the outer body G is melted and removed and disappeared is a cast product 6 Since it is possible to obtain a cast product that is a molded product by discharging it from the product and completely removing it, it is easy to completely remove it without leaving a residue, and it is possible to prevent defects such as wear and damage of the product and improve the quality of the cast product In addition to improving the yield, the yield can be improved, time and cost can be saved, and productivity can be improved.

Also in this embodiment, as long as the above-mentioned conditions are satisfied, as in the above-mentioned embodiment, thermoplastic synthetic resin such as polycarbonate synthetic resin (polycarbonate plastic) or heat resistance such as silicon rubber is used. The outer body G is composed of rubber and other materials, and inorganic materials such as gravel of rivers, seas and mountains, foundry sand itself and ceramics, or iron oxides and other metals in the form of powder, particles, lumps, etc. Needless to say, the core body H can be made of the above-mentioned materials or other materials.

Furthermore, even when a molded product is obtained by using the special casting core (special molding core) of the present invention, the die casting casting method and the gravity casting method of the above-described embodiments are not limited to the embodiments. Not limited, it is of course applicable to low pressure casting method, precision casting method and other casting methods, and many modifications are conceivable.
It is possible to obtain the same effect as that of the above embodiment.

The special molding core used in the present invention is not limited to the special molding core used in the casting method of the above-described embodiment, and many modifications are conceivable. Injection molding and other molding methods adopted as part of plastic molding, which is a molding method other than the casting method, and plastic molding special cores and ceramic molding used for molding methods such as injection molding adopted as part of ceramic molding. It can also be applied to a special core for use, can solve various problems as in the case of the above casting, and has the same excellent effects as those of the above-mentioned embodiment.

That is, the special molding core contributes to the formation of a desired molded product by maintaining its shape during molding and, after molding, is removed by residual heat or heat of the molded product or a solvent. Since the body dissolves and is removed and disappears, and the core body is also easily discharged, it is easy to completely remove without leaving any residue, and it is possible to prevent problems such as wear and damage of the product, It is possible to efficiently form a wide variety of molded products without any restrictions, improve the quality of molded products, improve the yield, and save time and money. Can be improved.

The molding special core used in the present invention is not limited to the above-mentioned embodiment, but can be applied to various shapes using various molding special cores. The quality can be improved and the like is not limited to the above-described embodiment, and many modifications can be considered.

According to this embodiment as described above, there are the following effects.

That is, according to the present embodiment, by using the molding special core as the core, it is possible to efficiently form a wide variety of molded products without being restricted in the shape and to produce the core. The idea is to improve the quality of molded products while improving the quality and expanding the scope of application.
For example, a molding method using a molding special core for casting to obtain a casting out of molding special cores used to form a molded product such as the above-mentioned cast product, a plastic molded product, or a ceramic molded product, In the case of, there are the following effects. (1) The outer body that wraps the core body inside prevents the components of the core body from penetrating into the molded product, thereby preventing adverse effects on the cast product and causing defects such as cavities in the cast product. It is possible to prevent the occurrence of defective products and prevent the production of defective cast products, thereby improving the yield and improving the productivity. (2) By avoiding the insertion of molten metal during molding, a molded product is obtained by molding using a special molding core having a smooth surface and excellent strength as compared with a conventional sand core made of foundry sand. ,
Prevents defects such as porosity and shrinkage in castings, prevents defective castings, and enables smooth surface finish without post-treatment such as machining, thus improving quality. . (3) By obtaining a molded product by using a special molding core, it is possible to make the wall thickness thinner than a conventional sand core made of foundry sand, thereby reducing the weight and the cost. You can (4) By obtaining a molded product using a special molding core, the dimensional accuracy is improved compared to the conventional sand core made of foundry sand, and post-treatment such as machining is unnecessary, and the number of steps is reduced. Can be planned. (5) By using the special molding core, conditions such as pressure resistance and heat resistance required for the core can be relaxed and the selection range of the core material can be expanded. (6) By using a special molding core, the pressure resistance and heat resistance of the core can be adjusted by selecting the material and the amount thereof. (7) By using the special molding core, molding of the core is facilitated, molding equipment is simplified, the number of steps is reduced, and time and cost can be reduced. (8) Since a special molding core is used, it does not break even if dropped or thrown, so handling is easy, and man-hours such as easy transportation and storage are reduced, and time and cost can be reduced. . (9) Since the molding special core does not contain a penetrating component such as a mold coating agent, a binder, a curing agent, etc., it is possible to prevent the core component from penetrating into the molded product, etc. The occurrence of defects can be prevented, the occurrence of defective products can be prevented, and the yield and productivity can be improved. (10) By using a special molding core, the hollow portion and the undercut portion can be easily formed, and the strength of the core is improved, so that the entire shape and size can be achieved without being restricted by the shape or size. Can be molded, and the range of application can be expanded. (11) By using a core that has the conflicting conditions of non-disintegrating property (heat resistance and pressure resistance) during molding and disintegrating property after molding (heat disintegrating property, solvent disintegrating property, etc.), Avoids problems such as molten metal insertion, maintains non-disintegration properties, facilitates disintegration properties and component removal after molding, prevents adhesion to molded products, and causes defects such as wear and damage to molded products. Occurrence can be prevented. (12) The molding special core does not contain components that are difficult to remove, such as a mold coating agent, a binder, and a curing agent, and has disintegration properties (heat disintegration property, solvent disintegration property, etc.) after molding. As a result, the core can be easily removed, the occurrence of pollution can be prevented, the man-hours can be reduced, and time and cost can be reduced. (13) In the molding core, a collapsible material such as an inorganic material that is a material of the core body that is discharged to the outside of the molded product by melting the outer body is reprocessed as the material of the core body. It can be reused and the material cost can be reduced.

Furthermore, even when a molded product is obtained by a molding method such as injection molding adopted as a part of plastic molding or a molding method such as injection molding adopted as a part of ceramic molding, the molding special product of the present invention is used. By using the molding method using the core, it is possible to efficiently obtain a desired molded article having excellent quality.

According to the molding method using the special molding core, the productivity and the applicable range can be improved even in the case of plastic molding or ceramic molding. By using the core, molding of the core becomes easy, molding equipment is simplified, the number of processes is reduced, and time and cost can be reduced.
It has various effects such as easy handling, easy transportation and storage, reduced man-hours such as no need for pressure adjustment during molding, and time and cost reduction.

The molding method using the molding special core of the present invention is not limited to the above-mentioned embodiments, and many modifications are conceivable, and the same effects as the above-mentioned embodiments can be obtained. .

[0148]

The present invention as described above has the following effects.

That is, according to the present invention, by using the special molding core as the core, it is possible to efficiently form a wide variety of molded products without being restricted by the shape and to improve the productivity. The idea is to improve the quality of molded products as well as improve the quality of molded products, and to improve the quality of molded products. In the case of a molding method using a molding special core for casting to obtain a cast product among the special cores, the following excellent effects are obtained. (1) The outer body that wraps the core body inside prevents the components of the core body from penetrating into the molded product, thereby preventing adverse effects on the cast product and causing defects such as cavities in the cast product. This has the effect of preventing the occurrence of defective products and preventing the production of defective products as cast products, thereby improving yield and improving productivity. (2) By avoiding the insertion of molten metal during molding, a molded product is obtained by molding using a special molding core having a smooth surface and excellent strength as compared with a conventional sand core made of foundry sand. ,
Prevents defects such as porosity and shrinkage in cast products, prevents cast product defects, and enables smooth surface finish without post-processing such as machining to improve quality. effective. (3) By obtaining a molded product by using a special molding core, it is possible to make the wall thickness thinner than a conventional sand core made of foundry sand, thereby reducing the weight and the cost. There is an effect that can be. (4) By obtaining a molded product using a special molding core, the dimensional accuracy is improved compared to the conventional sand core made of foundry sand, and post-treatment such as machining is unnecessary, and the number of steps is reduced. There is an effect that can be achieved. (5) The use of the special molding core has the effects of relaxing conditions such as pressure resistance and heat resistance required for the core, and expanding the selection range of core materials. (6) By using a special molding core, the pressure resistance and heat resistance of the core can be adjusted by selecting the material and the amount thereof. (7) The use of the special molding core has the effects of facilitating the molding of the core, simplifying the molding equipment, reducing the number of steps, and reducing the time and cost. (8) Since a special molding core is used, it does not break even if dropped or thrown, so handling is easy, and man-hours such as easy transportation and storage are reduced, and time and cost can be reduced. effective. (9) Since the molding special core does not contain a penetrating component such as a mold coating agent, a binder, a curing agent, etc., it is possible to prevent the core component from penetrating into the molded product, etc. The occurrence of defects is prevented, the occurrence of defective products is prevented, and the yield and productivity can be improved. (10) The use of the special molding core facilitates the formation of the hollow portion and the undercut portion, and improves the core strength, so that the shape and size of all shapes and sizes can be maintained. This has the effect of enabling molding and expanding the range of applications. (11) By using a core that has the conflicting conditions of non-disintegration during molding (heat resistance and pressure resistance) and disintegration after molding (heat disintegration, solvent disintegration, etc.), Avoids problems such as molten metal insertion, maintains non-disintegration, facilitates disintegration and component removal after molding, prevents adhesion to molded products, and causes defects such as wear and damage of molded products This has the effect of preventing the occurrence. (12) The molding special core does not contain components that are difficult to remove, such as a mold coating agent, a binder and a curing agent, and has disintegration properties (heat disintegration property, solvent disintegration property, etc.) after molding. As a result, the cores can be easily removed, the occurrence of pollution can be prevented, and the man-hours can be reduced to reduce the time and cost. (13) In the molding core, a collapsible material such as an inorganic material that is a material of the core body that is discharged to the outside of the molded product by melting the outer body is reprocessed as the material of the core body. It has the effect of being able to be reused in the above and can reduce the material cost.

Further, even when a molded product is obtained by a molding method such as injection molding adopted as a part of plastic molding or a molding method such as injection molding adopted as a part of ceramic molding, the molding special product of the present invention is used. By using a molding method using a core, there is an effect that a desired molded product having excellent quality can be efficiently obtained.

According to the molding method using the above-mentioned molding core, the productivity and the range of application can be improved even in the case of plastic molding or ceramic molding. By using the core, molding of the core becomes easy, molding equipment is simplified, the number of processes is reduced, and time and cost can be reduced.
It has various excellent effects such as easy handling, easy transportation and storage, reduction of man-hours such as no need for pressure adjustment during molding, and reduction of time and cost.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a molding die formed using a molding special core in a molding method using a molding special core according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state in which a molded product is molded by injecting a molding material into a molding die in a molding method using a special molding core according to one embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a molded product obtained by a molding method using a special molding core according to one embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a core body forming a special molding core used in a molding method using a special molding core according to an embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a special molding core used in a molding method using a special molding core according to an embodiment of the present invention.

FIG. 6 is a cross-sectional view showing an outer body forming a molding special core used in a molding method using the molding special core of one embodiment according to the present invention.

[Explanation of symbols]

1 Special core for molding (special core for casting) (Special core for plastic molding) (Special core for ceramic molding) 2 Upper mold 3 Lower mold 4 Mold (mold) (plastic molding) (ceramic molding) ) 5 cavity (molded product shape) 6 molded product (cast product) (plastic molded product) (ceramic molded product) G outer body (heat resistant outer body) H core body S filling space

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[Procedure amendment]

[Submission date] October 24, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 12

[Correction method] Change

[Correction content]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location B22C 3/00 C B28B 7/34 M B29C 33/38 8823-4F 33/54 8823-4F // B22D 17/22 H B29C 45/44 7639-4F B29D 22/00 2126-4F

Claims (17)

[Claims] 1. A molding core used for forming a hollow shape or an undercut shape into a molded product such as a molded product, a plastic molded product or a ceramic molded product, wherein the molding core comprises: A mold is formed using a special core for molding which includes a core body formed of a collapsible material such as river, sea, or mountain gravel, and an outer body that covers the surface (outer surface) of the core body. Forming molds such as plastic molds and ceramic molds,
A molding method using a special molding core, comprising molding a molded product such as a cast product, a plastic molded product, or a ceramic molded product using the molding die. 2. A molding core is one which has both conditions of non-disintegration during molding (heat resistance and pressure resistance) and disintegration after molding (heat disintegration property, solvent disintegration property, etc.). The molding method using the molding special core according to claim 1, which is a molding special core and is molded using the molding special core. 3. A core body made of a collapsible material is a core body made of an inorganic material such as gravel of river, sea or mountain, and a special molding core made of the core body is used. A molding method using the special molding core according to claim 1 or 2, characterized in that the molding is performed by molding. 4. The molding material according to claim 3, wherein the inorganic material is a core body which is river gravel, and the molding is performed using a molding core made of the core body. Molding method using a special core. 5. The molding according to claim 3, wherein the inorganic material is a core body which is gravel of the sea, and is molded by using a molding special core made of the core body. Molding method using a special core. 6. The molding according to claim 3, wherein the inorganic material is a core main body which is gravel of a mountain, and is molded using a molding special core made of the core main body. Molding method using a special core. 7. The molding special according to claim 3, wherein the inorganic material is a core body made of foundry sand, and molding is performed using a molding special core made of the core body. Molding method using a core. 8. The molding special core according to claim 3, wherein the inorganic material is a core body made of ceramic, and the molding is performed using a molding special core made of the core body. Molding method using a child. 9. A molding core having a core body mixed with powdery, granular, or lumpy metal, and molding using the molding core. Claim 1
A molding method using the special molding core according to claim 8. 10. A molding special core in which the metal mixed in the core body is iron such as iron oxide, and molding is performed using the molding special core. Item 10. A molding method using the special molding core according to Item 9. 11. A molding special core comprising an outer body having both conditions of non-disintegration during molding (heat resistance) and disintegration after molding (heat disintegration property, solvent disintegration property, etc.). 3. The molding method using the special molding core according to claim 1 or 2, wherein the molding is performed using the special molding core. 12. The molding according to claim 1, wherein the outer body is a molding special core which is a heat resistant outer body, and the molding is performed using the molding special core. Item 11. A special molding core according to item 11. 13. The molding according to claim 12, wherein the heat-resistant outer body is a molding special core made of a heat-resistant synthetic resin, and the molding is performed using the molding special core. Molding method using a special core. 14. The molding according to claim 13, wherein the heat-resistant synthetic resin is a molding special core made of a thermoplastic synthetic resin, and the molding is performed using the molding special core. Molding method using a special core. 15. A molding special core, wherein the thermoplastic synthetic resin is a polycarbonate synthetic resin (polycarbonate plastic), and molding is performed using the molding special core. Molding method using special core for molding. 16. The molding special according to claim 12, wherein the heat resistant outer body is a molding special core made of heat resistant rubber, and the molding is performed using the molding special core. Molding method using a core. 17. A molding special core according to claim 16, wherein the heat-resistant rubber is a molding special core made of silicone rubber, and the molding is performed using the molding special core. Molding method using.