JPH08155624A - Forming method using special core for forming - Google Patents

Abstract

PURPOSE: To prevent the deformation and the breakage of a formed product by using a core formed to uneven thickness at a part of the thickness, forming a formed mold and pressure-pouring molten metal in the mold. CONSTITUTION: In the hollow resin core 1, the thickness of a thin forming part N is thinner than the other part. The resin core 1 is arranged between an upper mold 2 and a lower mold 3 to form the mold 4 having a cavity 5. The molten metal is poured into the cavity 5 while applying the pressure to the molten metal. Even if the resin core 1 is brought into contact with the molten metal, this core is not immediately melted, but the shape at the initial stage is held, and the cast product 6 having the shape corresponding to the shape of the cavity 5 is cast. It is prevented that the cast product 6 is deformed or broken by deforming the thin forming part N when the cast product 6 cools and shrinks. The resin core 1 is melted by the preheat of the cast product 6, and made to be small and easily removed. The formation of the one having hollow shape and under-cut shape or complicate shape can be executed.

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 special molding core, and in particular, it is possible to prevent deformation or damage of a molded product due to the influence of a molding material such as molten metal. The present invention relates to a molding method using a molding special core that can obtain a cast product such as a die cast product having a shape or an undercut shape, or a molded product such as a plastic molded product or a ceramic molded product.

[0002]

2. Description of the Related Art In casting adopted as a part of machining, a hollow shape and an undercut shape are formed.
Non-disintegrating cores or disintegrating cores are used.

By the way, there is a metal core as the former (non-collapsible 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), there is a sand core in which a binder and a curing agent are mixed and fired, but it is difficult to mold and handle, and it easily collapses, and the pressure resistance during casting and the collapse after casting. Since it is difficult to combine with the property, it becomes glassy after casting and it is difficult to completely remove it.

Therefore, it has been proposed to apply a mold coating agent to the surface of the sand core, but there is a problem that defective products are generated due to the adverse effects such as the formation of porosity and shrinkage due to the permeation of the components, and the problem cannot be solved.

Further, in the die casting, the sand core cannot be used due to a defect such as insufficient strength. For example, it is impossible to form the hollow shape or the undercut shape of the intake manifold or the exhaust manifold of the engine by the die casting. There was a problem.

The sand core is difficult to mold and easily collapses.
It has many drawbacks such as difficulty in handling, and it is difficult to meet the contradictory conditions of pressure resistance during casting and disintegration after casting.Therefore, multiple steps are required from the factor of increasing the number of steps due to sand core characteristics, It had the drawback of being time consuming and expensive.

On the other hand, plastic molding and ceramic molding have various problems similar to the above casting.

For example, the molding core needs to be formed from a specific material having pressure resistance and heat resistance during molding, which causes problems such as difficulty in molding the core and high cost.

Therefore, in order to solve these problems, the present inventor first forms a hollow shape or an undercut shape into a cast product such as die casting, a molded product such as a plastic molded product or a ceramic molded product. In a molding core used for, a molding special core characterized by forming the molding core from a non-sand core, and a molding method using the molding special core, and A molded product molded using the special core has been proposed (Japanese Patent Application Nos. 4-339733 and 4-33).
9734, Japanese Patent Application No. 4-339735, etc.).

By the way, when the molding core is formed of a non-sand core to form a molding special core, and when a molding method using the molding core is used, the size and shape of the molded product are obtained. Depending on the type, there is a problem that deformation or damage may occur during molding.

[0012] After that, the present inventor continued further research,
Molding method using special core for molding that can solve problems such as relatively large things such as engine intake manifold and exhaust manifold, hollow shape of complex shape and undercut shape can be formed by die casting As for, the more appropriate one was investigated.

[0013]

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

That is, when a molten metal is pressurized and poured into a mold by molding with a specific molding special core, when the molten metal is cooled, die casting due to the influence of the molten metal or the like occurs. By preventing deformation or damage of the cast product, it is possible to obtain a cast product such as a die cast cast product having a target shape in which a hollow shape or an undercut shape is formed.

On the other hand, also in the case of plastic molding or ceramic molding, as in the casting such as the die casting, the molding such as the die casting casting is carried out by using the particular molding core and the particular molding method. As in the case of the method, after injecting the molding material into the molding die, when cooling the molding material, by preventing the deformation or damage of the molded product due to the influence of the molding material, etc., the hollow shape It is possible to obtain a molded product having a target shape in which the undercut shape and the like are formed.

[0016]

According to the present invention, a molding core is formed of a non-sand core, and a space is formed inside the molding core. Moreover, a molding special core in which a part or the whole of the wall thickness of the molding core is formed to have a non-uniform thickness is used, and the molding special core is made of an upper die and a lower die. It is arranged inside an outer mold such as a mold to form a mold having a hollow part in the shape of a molded product, a molding mold such as a plastic molding mold, a ceramic molding mold, and the like, and the molten metal is pressurized and poured into the molding mold. By injecting a molding material, etc., a molded product such as a die-cast molded product having a desired shape with a hollow shape or an undercut shape, or a molded product such as a plastic molded product or a ceramic molded product is formed. And a molding method using a special molding core.

[0017]

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

That is, according to the present invention, when the molding material is cooled, a part of the molding special core having the non-uniform thickness is deformed, so that the molding product is influenced by the molding material or the like. It is possible to prevent the deformation and damage of the above, and to mold it into a target shape having a hollow shape or an undercut shape.

That is, according to the present invention, it is possible to easily form a hollow shape or an undercut shape, which is impossible by conventional die casting, by forming a specific molding core using a specific molding method. Not only is it possible, but it is possible to cast all shapes and sizes regardless of shape and size. Moreover, when the molten metal is poured under pressure into the mold and then cooled, a thin wall is formed. By deforming the part and creating a gap between it and the die cast product,
It is possible to obtain a cast product such as a die cast cast product having a target shape in which a hollow shape, an undercut shape or the like is formed by preventing deformation or damage of the die cast cast product due to the influence of the molten metal or the like.

On the other hand, also in the case of plastic molding or ceramic molding, as in the case of casting such as die casting, the molding is carried out by a particular molding method using a particular molding core. As in the case of the casting method, it not only facilitates the formation of hollow shapes and undercut shapes, but also enables the molding of all shapes and sizes regardless of shape or size, and The purpose of forming a hollow shape or an undercut shape by preventing the deformation or breakage of the molded product due to the influence of the molding material or the like when the molding material is cooled after being injected into the A shaped molded article can be obtained.

Further, by doing so, it is possible to improve the productivity and expand the range of application, and it is possible to efficiently obtain a molded product of a desired shape with excellent quality.

[0022]

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, according to the present invention, the molding core is formed of a non-sand core, a space is formed inside the molding core, and the wall thickness of the molding core is one. A molding special core whose parts or all are formed to have non-uniform thickness is used, and the molding special core is provided inside an outer mold such as a mold including an upper mold and a lower mold. By forming a mold having a cavity having a shape of a molded product, a molding mold such as a plastic molding mold or a ceramic molding mold, and pouring a molding material such as pressurizing molten metal into the molding mold, a hollow shape or A molding method using a special molding core, which is characterized in that a molded product such as a die-cast molded product having a desired shape with an undercut shape or the like, or a molded product such as a plastic molded product or a ceramic molded product is molded. is there.

Therefore, the non-sand core used in the present invention is
Both conditions of non-disintegration during molding (heat resistance and pressure resistance) and disintegration after molding (heat disintegration, solvent disintegration, etc.) are required. Further, the non-sand 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.

Here, a case where a core made of synthetic resin (plastic) is used as the non-sand core will be described. A core (synthetic resin core or plastic core) made of a synthetic resin (plastic) as a non-sand core that is the molding special core (hereinafter referred to as "resin core") 1
Is made of synthetic resin (plastic).

The resin core 1 is made of synthetic resin (plastic) by a synthetic resin molding method (plastic molding method) such as injection molding, as well shown in FIGS. 4 and 5. It is formed in a hollow shape having a hollow portion S.

Then, using the molding special core 1,
Molded products such as cast products, plastic molded products and ceramic molded products can be 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 resin core 1, as shown in FIG. It is possible to form the molding die 4 which is disposed between the mold 2 and the lower mold 3 and has the hollow portion 5 having a shape corresponding to the shape of the molded product 6 to be molded.

In the present embodiment, by using the above-mentioned non-sand core, casting products such as die cast products having a desired shape in which a hollow shape or an undercut shape is formed, plastic molded products, ceramic molded products, etc. Among the molding methods using a special core, which is characterized by molding a molded product, a casting method using a special core for molding a cast product will be described.

Here, a case of performing die-casting with high productivity as one of casting methods and a case of using a synthetic resin core as a non-sand core will be described.

That is, in this embodiment, casting is performed in the following steps.

First Step First, although not shown, in the same manner as described above, a polycarbonate synthetic resin (polycarbonate plastic) having excellent heat resistance and moldability is used among the synthetic resins (plastics), as shown in FIG. And as best shown in FIG.
The hollow resin core 1 having the hollow portion S formed therein is molded.

The resin core 1 is formed such that a part of its wall thickness is non-uniform.

The resin core 1 has a non-uniform thickness portion,
It is formed in the locally formed thin portion N. Further, the resin core 1 is formed by forming the local thin-wall forming portion N to have a predetermined length L and a substantially uniform thickness.

For example, in the hollow resin core 1 having the hollow portion S formed therein, the thickness T of the non-thin portion is 5 mm.
When, the wall thickness t of the thin wall forming portion N is 2 mm. Further, the local thin-walled forming portions N are formed at two locations on the same circumferential surface of the resin core 1.

As described above, the resin core 1 is formed in a hollow shape having the hollow portion S therein, and is formed on the same circumferential surface.
The wall thickness of the portion is formed in a local thin-wall forming portion N with a predetermined length over a predetermined width.

Second Step Subsequently, as shown well in FIG. 1, the resin core 1 is disposed between the upper mold 2 and the lower mold 3 so that a hollow shape or an undercut shape is formed. A mold 4 having a cavity 5 corresponding to the shape of the formed die-cast product is formed.

Third Step Next, as best shown in FIGS. 1 and 2, a pressure is applied to the molten metal such as aluminum molten metal in the cavity 5 formed in the mold 4 depending on the material of the cast product. Pouring while adding.

At this time, since the resin core 1 has a large heat capacity, it has high heat resistance to the molten metal and high pressure resistance. The initial shape can be retained without deformation. Further, the temperature of the molten metal is about the initial temperature (for example, about 6% for aluminum molten metal) before reaching the cavity 5 of the mold 4.
Since the temperature decreases compared to 60 degrees C), the resin core 1
Due to its own temperature and heat capacity, the initial shape can be maintained without immediate melting even when the molten metal acts.

Therefore, the casting 6 having a shape corresponding to the shape of the cavity 5 is cast in a state where the resin core 1 is maintained in its original shape without being deformed.

Fourth Step Subsequently, as shown in FIGS. 2 and 3, the high-pressure molten metal poured as described above is cooled to form a hollow shape or an undercut shape. A die cast product 6 having a shape is formed. The cooling includes natural cooling and forced cooling, but in the present embodiment, natural cooling is performed.

At this time, as shown in FIGS. 4 and 5, the resin core 1 is formed such that a part of its hollow wall thickness is nonuniform. Further, the resin core 1 has a non-uniform thickness portion formed in a local thin-wall forming portion N, and the thin-wall forming portion N is formed by thinning a predetermined length L into a substantially uniform thickness. Has been done. For example, when the thickness T of the non-thin portion of the resin core 1 is 5 mm, the thickness t of the thin portion N is 2 mm.

The thin-wall forming portion N is formed at two locations on the same peripheral surface of the main body G.

As described above, the resin core 1 is formed in the local thin-walled forming portion N with a predetermined thickness over a predetermined width such that the thicknesses of the two locations on the same peripheral surface are predetermined.

Furthermore, when the molten metal is pressurized and poured into the mold 4 and then the molten metal is cooled, the thin-walled forming portion N formed to have a substantially uniform thickness is deformed. That is, as well shown in FIG. 6, the arcuate thin-walled forming portion N forming a part of the cylindrical shape is deformed into a substantially M shape (substantially mountain shape), and a cast product 6 that is a molded product is obtained. A gap is created between the two.

In this way, the arc-shaped thin-walled forming portion N, which is a part of the resin core 1, is deformed into a substantially M-shape, so that the cast product 6 due to the influence of the molten aluminum, which is the casting material, or the like.
Since it is possible to prevent defects such as deformation and damage of the
As well shown in FIG. 3, a cast product 6 having a desired shape in which a hollow shape C, an undercut shape U and the like are formed can be cast.

Fifth Step Subsequently, as shown in FIG. 2 and FIG. 3, a die-cast casting 6 having a target shape having the hollow shape C and the undercut shape U formed as described above is formed. Mold 4
Take out from.

Sixth Step Next, although not shown, the casting is completed by removing the resin core 1 remaining inside the casting 6.

At this time, the resin core 1 contributes to the formation of a desired casting 6 by maintaining its shape during casting, and after casting, by the residual heat or heating of the casting 6. Melt and cast alone or in combination with drawing 6
It is removed from and eliminated so that no residue remains.

In this case, in this embodiment, the resin core 1 is removed by removing the residual heat alone or by using the residual heat and the extraction together, or by using the residual heat and the heating together, or the residual heat and the heating and extraction. Are used together, or both heating and drawing are performed together, or only heating is performed.

Further, the resin core 1 can be removed by using a solvent, particularly an organic solvent, without being limited thereto, and the solvent removal can be carried out in combination with residual heat or withdrawal as in the above. And heating, or residual heat, heating and drawing, or heating and drawing, or the solvent alone.

As described above, in the case of die casting, which is the first embodiment of the molding method using the special molding core of the present invention, the resin core 1 retains its shape during casting. In addition to contributing to the formation of the intended cast product 6, after casting, the cast product 6 is melted and removed by residual heat or heating of the cast product 6 and can be removed without leaving a residue.

Seventh step Further, although not shown in the drawing, unnecessary parts such as burrs of the cast product 6 are removed to form a finished product such as a hollow shape C and an undercut shape U. You can get a product that is

At this time, the resin core 1 is removed and disappears from the molded product, but depending on the shape and size, the whole or a part can be extracted and reused as the material of the resin core 1, thus reducing the material cost. Can be planned.

As described above, according to the first embodiment, by molding with a specific molding method using a specific molding special core, a hollow shape and an undercut which cannot be obtained by conventional die casting are obtained. Not only is it easy to form shapes, but it is also possible to form relatively large parts such as engine intake manifolds and exhaust manifolds, hollow shapes with complicated shapes, and undercut shapes by die casting. Regardless of the shape or size of the die, it is possible to cast the molten metal into the mold and then cool the molten metal. By preventing the generation, it is possible to obtain a cast product such as a die-cast cast product having a target shape in which a hollow shape or an undercut shape is formed. Therefore, as compared with the conventional sand core casting method, (1) core coating mold, (2) core drying, (3)
Sand removal of castings, (4) sand heat treatment (sand baking) of castings,
(5) The number of man-hours can be reduced by eliminating the need for the five steps of sand drop inspection of cast products.

Next, the operation of this embodiment will be described.

As described above, the molding method using the special molding core of this embodiment has the following effects.

That is, according to the present embodiment, after pouring molten metal into the cavity 5 formed in the mold 4 while applying pressure to molten metal such as aluminum molten metal according to the material of the cast product, the high pressure is poured. When the molten metal is cooled, the cast product 6 having the target shape is formed. When the molding material is cooled, a part of the special molding core having the nonuniform thickness is deformed. The molded product is prevented from being deformed or damaged due to the influence of the molding material or the like, and is molded into a target shape having a hollow shape C, an undercut shape U, or the like.

In this case, when the molten metal that has been poured under pressure is cooled, the thin-walled forming portion N formed to have a substantially uniform thickness is deformed into a substantially M-shape, and a gap is formed between the thin-walled formed portion 6 and the cast product 6. In this state, the cast product 6 is prevented from being deformed or damaged due to the influence of the aluminum melt, which is the casting material, and the cast product 6 having the target shape in which the hollow shape C, the undercut shape U, etc. are formed. It can contribute to casting.

As described above, according to this embodiment, by forming a specific molding core using a specific molding method, it is possible to form a hollow shape or an undercut shape, which is impossible by conventional die casting. Not only is it easy to perform, but also relatively large things such as engine intake manifolds and exhaust manifolds, hollow shapes with complicated shapes and undercut shapes can be formed by die casting, regardless of shape and size, All shapes and sizes can be cast, and when the molten metal is pressurized and poured into the mold, when the molten metal is cooled, defects such as deformation and damage of the die cast product due to the influence of the molten metal etc. occur. It is possible to obtain a cast product such as a die cast cast product having a target shape in which a hollow shape or an undercut shape is formed.

Further, by doing so, it is possible to improve the productivity and expand the range of application, and it is possible to efficiently obtain a molded product of a desired shape with excellent quality.

The special molding core used in the method of the present invention is not limited to the above-mentioned embodiment, but many modifications are conceivable, and different structures, shapes and sizes can be adopted. Of course.

For example, FIG. 7 is a cross-sectional view showing a second embodiment of a special molding core used in the method of the present invention. The hollow resin core 1 has a small size and is therefore substantially uniform. Only one local thin thickness forming portion N is formed on the same circumferential surface of the resin core 1.

FIG. 8 is a cross-sectional view showing a third embodiment of a molding special core used in the method of the present invention. Since the hollow resin core 1 has a large size, The local thin-walled portions N having a substantially uniform thickness are formed at four locations on the same circumferential surface of the resin core 1.

Furthermore, FIG. 9 is a cross-sectional view showing a fourth embodiment of a special molding core used in the method of the present invention. The hollow resin core 1 is formed to have a non-uniform thickness throughout. As described above, the thin-wall forming portion N is formed by gradually forming the entire wall thickness to be non-uniform.

According to the present embodiment, as well shown in FIG. 10, when the molten metal is cooled, the thin-walled forming portion N is deformed into a substantially M shape (generally mountain shape), and a cast product which is a molded product. A gap is formed between the die cast casting 6 and the die 6, so that the die casting 6 can be prevented from being deformed or damaged, and the die cast casting 6 having the desired shape in which the hollow shape C, the undercut shape U and the like are formed can be cast. FIG. 11 is a cross-sectional view showing a fifth embodiment of the molding special core used in the method of the present invention, in which the local thin-walled forming portion N of the hollow resin core 1 has a substantially uniform thickness, The resin core 1 is formed at two locations on the same circumferential surface facing each other.

As described above, since the resin core 1 is formed in a hollow shape having the hollow portion S therein and is formed in the thin-walled forming portion N with a predetermined length over a predetermined width, the molten metal is formed. At the time of cooling, the thin-walled forming portion N is deformed to create a gap between the thin product forming portion N and the cast product 6, whereby defects such as deformation and damage of the cast product 6 can be prevented, and a hollow shape C, an undercut shape U, etc. are formed. It is possible to cast a die-cast casting 6 having a desired shape and excellent quality.

At this time, the molding special core used in the present invention is not limited to the above-mentioned embodiment, but various shapes, sizes and forming positions of the thin wall forming portion N, and the core itself. It can be applied to various shapes using various molding special cores, such as having various shapes and sizes, can improve the quality of molded products, and is not limited to the above-mentioned examples.
Many variations are possible.

For example, the number of the thin-walled forming portions N is not limited to one, two or four in the above-mentioned embodiment, and it is needless to say that the number may be three, five or more, which is the other number. Is. The shape of the thin-walled forming portion N is not limited to the shape having the uniform thickness in the above-described embodiment, and it is needless to say that the thin-wall forming portion N can be formed in the shape having other non-uniform thickness. further,
The shape of the thin-wall forming portion N is not limited to the shape in which a part of the wall thickness of the above-described embodiment is formed to be substantially uniform, and it goes without saying that a part of the wall thickness can be formed to have a non-uniform thickness.

Next, a second embodiment of the present invention will be described with reference to the drawings.

That is, FIGS. 3 and 12 to 14 show a second embodiment of the present invention, in which a special molding core is used.
Of the molding methods for molding a molded product such as a molded product having a hollow shape C or an undercut U shape, or a molded product such as a plastic molded product or a ceramic molded product, the case of performing die casting will be described.

In this case, the resin core 1 having the hollow portion S is used in the first embodiment, but the following non-sand core is used in the second embodiment. Cast.

As shown in FIG. 13 and FIG. 14, the casting special core 1 which is the non-sand core has a hollow main body G in which a filling space S which is a hollow portion is formed. The filling body H is filled in the filling space S. The hollow main body G having the filling space S is formed of a polycarbonate synthetic resin which is a thermoplastic synthetic resin. In addition, the filling body H is formed of shirasu, which is a gravel of a mountain, which is a collapsible material, and is filled in the filling space S of the main body G.

Then, in the same manner as the casting method such as the die casting method of the first embodiment, the casting method such as the die casting casting method can be carried out by using the casting special core 1. The same effect as that of the embodiment can be obtained.

In this case, as well shown in FIG. 12, the high-pressure molten metal that has been poured is cooled to form the cast product 6 having the target shape shown in FIG.

The cooling includes natural cooling and forced cooling. In the present embodiment, natural cooling is used.

At this time, as shown in FIGS. 13 and 14, the casting special core 1 as the molding special core has a hollow shape in which the filling space S is filled with the filling body H. Two wall thicknesses on the same peripheral surface of the main body G are formed in a local thin-wall forming portion N over a predetermined width.
Is formed by forming a thin wall having a predetermined length L substantially uniformly (for example, when the wall thickness T of the non-thin wall forming portion of the hollow main body G is 5 mm, the wall thickness t of the thin wall forming portion N). Is 2 mm
Like).

Then, after the molten metal is poured into the mold 4 under pressure, when the molten metal is cooled, the thin-walled forming portion N formed to have a substantially uniform thickness is deformed. That is, as well shown in FIG. 6, the arcuate thin-walled forming portion N forming a part of the cylindrical shape is deformed into a substantially M shape (substantially mountain shape), and a cast product 6 that is a molded product is obtained. A gap is created between the two.

In this way, the arc-shaped thin-walled forming portion N, which is a part of the casting special core 1, is deformed into a substantially M-shape,
As shown in FIG. 3, the hollow shape C and the undercut shape U are prevented by preventing defects such as deformation and damage of the cast product 6 due to the influence of the aluminum melt, which is the casting material.
It is possible to contribute to the casting of the cast product 6 which is excellent in the quality of the target shape in which the like and the like are formed.

The method of the present invention as described above is not limited to the die casting in each of the first and second embodiments, but may be a sand type gravity casting method, a die gravity casting method, a low pressure casting method or a low pressure casting method. It can be applied to precision casting methods and other casting methods, and can obtain the same excellent effects as the above-mentioned respective examples, and also can be applied to plastic molding, ceramic molding and other molding methods, and the same excellent effects as the above-mentioned respective examples It is possible to efficiently obtain a molded product having a desired shape with excellent quality.

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

Next, the operation of the second embodiment will be described.

Also in the case of this embodiment, similarly to the first embodiment, after the aluminum melt or the like is pressurized and poured into the cavity 5 formed in the mold 4 according to the material of the cast product, the melt is cooled. As a result, the casting 6 having the desired shape is formed, but when the molten metal is cooled, the thin-walled forming portion N is deformed into a substantially M shape, and a gap is created between the casting 6 and the casting 6. It is possible to prevent defects such as deformation and damage of the cast product 6 due to the influence of molten metal and the like, and contribute to casting of the cast product 6 having the target shape in which the hollow shape C, the undercut shape U, and the like are formed.

In addition to the above, according to the above-described embodiment, the following remarkable effects are further provided.

That is, according to the second embodiment, since the casting special core 1 uses the core filled with the filling body, the core has pressure resistance and heat resistance with the filling body filled. Since it is sufficient to satisfy the conditions such as the heat resistance and the like, the conditions such as pressure resistance and heat resistance required for the core can be relaxed, the selection range of the core material can be expanded, and the filler and the amount can be selected. By doing so, the pressure resistance and heat resistance of the core can be adjusted.
Further, since the heat-resistant main body G is integrally formed on the surface of the filling body H, the heat capacity is large, and the heat resistance and pressure resistance are high,
The initial shape can be maintained without thermal deformation or pressure deformation. Further, since the main body G is completely removed and disappeared due to residual heat of the cast product 6 and only the filling body H remains, it is easy to discharge the filling body H from the casting product 6 and the special core 1 for casting from the casting product 6 is obtained.
Can be completely removed, defects such as wear and damage of products can be prevented, the quality and yield of cast products can be improved, time and cost can be saved, and productivity can be improved.

Therefore, the cast product 6 having a shape corresponding to the shape of the hollow portion 5 is efficiently cast.

As described above, according to the present embodiment, by using a specific molding special core for molding by a specific molding method, a hollow shape or an undercut shape U shape which cannot be obtained by conventional die casting. Not only is it easy to form, but also relatively large parts such as engine intake manifolds and exhaust manifolds, hollow shapes with complicated shapes, and undercut shapes can be formed by die casting, regardless of shape and size. Instead, it is possible to perform casting such as die-cast casting of all shapes and sizes.

Therefore, since the surface of the special molding core used is smoother than the rough surface of the conventional sand core, the molded product molded according to the above-mentioned embodiment has a hollow shape or an undercut shape. The inner surface is formed as a smooth surface without a rough surface, eliminating the need for secondary processing such as machining for inner surface smoothing, and preventing defects in the molded product such as wear and damage to the molded product. It is possible to improve the performance of the product using the product.

Although all of the above-mentioned examples have been described with respect to die casting, the molding method using the special molding core of the present invention is not limited to die casting, and sand sand gravity casting, metal die gravity casting, and low die casting. Of course, it can be applied to a pressure casting method, a precision casting method, and other casting methods. Further, the molding method using the molding special core of the present invention is not limited to the above-mentioned casting method, but can be applied to other molding methods such as plastic molding and ceramic molding, and is as excellent as the above-mentioned die-cast casting and other casting methods. The effect can be obtained, and a molded product having a desired shape and excellent quality can be efficiently obtained.

As described above, according to the method of the present invention, it is possible to efficiently form a wide variety of molded articles without being subject to shape restrictions, and cast articles, plastic molded articles and ceramics having a hollow shape or an undercut shape are formed. It is possible to obtain molded products such as molded products.

Moreover, molding of all shapes and sizes is possible without being restricted by the shape and size, the range of application is greatly expanded, the degree of freedom in design is improved, and the product performance is improved.
Further, the productivity can be improved and the cost can be reduced by reducing the weight.

Next, with reference to the attached drawings, a method of forming the special molding core used in the second embodiment will be described.

13 and 14 show a method of forming a special molding core for use in the second embodiment of the present invention. The special molding core 1 can be formed by various methods.

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

First, a first embodiment of a method of forming the molding special core 1 used in the method of the present invention will be described with reference to the drawings. That is, FIGS. 13 and 14 show a first embodiment of a method for forming a molding special core used in the second embodiment of the present invention.

First, shirasu, which is mountain gravel as an inorganic material, is hardened with glue to obtain a filling body H having a predetermined shape. Subsequently, a polycarbonate synthetic resin, which is a heat-resistant synthetic resin, is formed on the surface of the filling body H with a predetermined thickness to form a main body G made of a heat-resistant main body. In this way, the molding special core 1 having a predetermined shape in which the heat-resistant main body G is formed on the surface of the filling body H can be formed.

When the special molding core 1 is used for molding, the strength is improved, it is less likely to be broken, and it is easy to handle. Therefore, molding is possible regardless of shape or size, expanding the range of application and improving productivity. Therefore, it is possible to efficiently obtain a molded product having excellent quality.

Next, a second embodiment of the method for forming the special molding core 1 used in the method of the present invention will be described with reference to the drawings. That is, FIG. 13 and FIG. 14 show a second embodiment of the method for forming the molding special core used in the second embodiment of the present invention.

First, a filling space S is formed inside by forming a polycarbonate synthetic resin into a predetermined shape with a predetermined thickness.
The main body G is formed of a heat-resistant main body having a hollow shape. Next, the filling space S of the main body G is filled with shirasu, which is a mountain gravel, and hardened with glue to form a filling body H having a predetermined shape. In this way, it is possible to form the special molding core 1 having a predetermined shape in which the filling body H is filled and formed in the filling space S of the body G.

When the special core 1 for molding is used for molding, the strength is improved, it is hard to break and it is easy to handle, so that molding is possible regardless of the shape or size, and the range of application is expanded and the productivity is improved. Therefore, it is possible to efficiently obtain a molded product having excellent quality.

FIG. 15 shows a special core for molding of the seventh embodiment used in the method of the present invention and an engine intake manifold which is a molded product. The intake manifold I of the engine has a hollow shape C and an undercut shape U of complicated shapes and is relatively large.
Conventionally, there is a problem that deformation or damage may occur during molding, but the special core for molding of the present invention solves these problems, and a relatively large or complicated hollow shape C It is possible to solve the problems such as the formation of an intake manifold of an engine, which is a die-cast product having an undercut shape U formed therein.

FIG. 16 shows the special core for molding of the eighth embodiment used in the method of the present invention and the exhaust manifold of the engine which is the molded product. In the exhaust manifold E of the engine, the hollow shape C and the undercut shape U having a complicated shape are formed as in the above embodiment, and
Although it is relatively large, there is a problem that deformation and damage may occur during molding conventionally, but the special core for molding of the present invention eliminates these problems and enables die casting. It is possible to solve the problems such as

The special molding core, the filling body, and the main body used in the method of the present invention are not limited to the examples, but can be applied to various materials, shapes, and sizes, and many variations are possible. ,
It is possible to obtain the same effect as that of each of the above embodiments.

Further, the molding using the special molding core of the present invention is not limited to the molding method of the embodiment, but can be applied to molded products of various materials, shapes and sizes. To improve the quality of molded products by adding specific processes, etc.
The present invention is not limited to the molding method of the embodiment, and many modifications can be considered.

Further, the filling body forming the special molding core is required to have non-disintegrating property while the surface is covered with the main body at the time of molding and disintegrating property after molding.

Fillers satisfying the above conditions include, for example, fillers made of a collapsible material such as an inorganic material such as gravel of river, sea or mountain. Among them, as the inorganic material, there are river gravel, sea gravel, and mountain gravel, as well as raw foundry sand itself that does not contain a binder, a hardening agent, etc., or a powdery, granular, or lumpy ceramic ( There are new ceramics and old ceramics). Further, the filling body may be made of gravel, foundry sand, ceramics or the like alone, or may be a mixture thereof with a powdery, granular or lumpy metal. Examples of the metal include iron such as iron oxide, aluminum such as aluminum oxide, and other metals.

The main body may be formed on the entire surface of the filling body as in the embodiment, or may be formed on most (or part) of the surface of the filling body depending on the shape of the molded product.

The main body has non-disintegration properties (heat resistance and pressure resistance) at the time of molding, and disintegration properties (heat disintegration property, solvent disintegration property, etc.) after molding, and the filler is enclosed inside. It is required to protect and further completely prevent gas generation from the molding special core even if gas is generated in the filling body, and not to adversely affect the molded product. A material similar to the resin core as the sand core is suitable.

The resin core as the non-sand core, which is the special molding core used in the method of the present invention, and the material of the main body that constitutes the non-sand core are non-disintegrating (heat resistant) during molding. Properties and pressure resistance) and disintegration property after molding (heat disintegration property, solvent disintegration property, etc.) are required, and it is required not to give adverse effects to the molded product such as gas generation during molding. .

Materials satisfying the conditions include synthetic resins (plastics) and other materials. Among them, the synthetic resins include the following.

That is, the synthetic resin includes, for example, a thermosetting synthetic resin (thermosetting plastic) and a thermoplastic synthetic resin (thermoplastic), and both of the above conditions are satisfied. It is possible to obtain a molded product that sufficiently satisfies

Further, the most suitable one of the thermoplastic synthetic resins is the polycarbonate synthetic resin of the embodiment, which satisfies the above conditions and sufficiently satisfies the intended purpose. Casting products and other molded products. Can be obtained. Next to this, there are fluororesins (polyfluorethylene resins) such as tetrafluoroethylene resin, polyimide resins, polyamideimide resins and polysulfone resins,
Since all of the above conditions are satisfied, 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 can provide a molded product satisfying the initial purpose.

Further, it is a matter of course that, as the synthetic resin, any thermoplastic synthetic resin, thermosetting synthetic resin or other synthetic resin other than those in the examples and the above list can be used as long as they satisfy the above conditions. The same effect as that of the embodiment can be obtained.

Further, it goes without saying that other materials can be used as well as the synthetic resin material as long as the above conditions are satisfied.

Other materials satisfying the above conditions include heat-resistant synthetic rubber, silicon rubber, fluorine rubber and the like, for example, heat-resistant rubber such as silicon rubber, and any of the above conditions can be satisfied. However, it is possible to obtain the same effect as that of the above embodiment.

Further, as the material, other than the above synthetic resins and rubbers, low melting metals such as tin, lead and antimony and ceramics, as long as they satisfy the above conditions,
In addition to other single materials, FRR (fiber reinforced rubber), FRP (fiber reinforced plastic) and GFR
P (glass fiber reinforced plastic) and other composite materials can be used, various materials can be used, and the same effects as those in the above-described embodiment can be obtained.

The resin core as a non-sand core, which is a special molding core for satisfying the disintegration property (heat disintegration property, solvent disintegration property, etc.) after molding, and the main body constituting the non-sand core Basically, it is dissolved and removed by residual heat of the molded product, but depending on the size and shape of the core and the molded product, it is difficult to dissolve and remove with only the residual heat of the molded product. And can be removed from a molded product such as a cast product.

In this case, the removal of the resin core and the main body is not limited to the method of completely dissolving and removing the resin core inside the molded product, but if the resin core or the like can be removed from the molded product, the surface of the resin core or the like is dissolved. It is possible to take out from the molded product in the state of being melted, or in a state in which a part or most of the resin core or the like is melted or in a state of semi-molten.

At this time, the remaining portion of the extracted resin core or the like can be reused without discarding, the cost can be reduced, and the pollution problem can be solved.

When the special core for molding or the main body is insufficiently or difficultly or impossiblely removed by residual heat or extraction, heating alone or heating in combination with residual heat or extraction can be performed. At this time, as a heating removal method, heating by a burner,
Heating in a heating tank, heating with high-temperature and high-pressure steam, heating with shot blasting to blast (jet) other shots such as metal powder such as alumina powder, heating with microwaves or electromagnetic induction heating,
There are other heating methods, and in any case, the non-sand core after molding can be completely removed by heating.

Further, depending on the shape of the molding special core or the shape of the molded product, in addition to residual heat, heating or drawing, a solvent, particularly an organic solvent, may be used alone or in combination with residual heat, heating or drawing. The special core or body can be removed from the molded product. This solvent removal method, there is a solvent spray removal or removal by immersion in a solvent tank, or removal by using a microwave immersed in a solvent tank, other solvent removal methods, in any case after molding The non-sand core can be completely removed by the solvent. As the solvent, when the molding special core or the main body is a polycarbonate synthetic resin, normal alkylbenzene (trade name "Nonion" or the like) is sufficiently satisfactory in terms of function and cost, and there is no problem in actual use. In addition to these, as the solvent of the polycarbonate synthetic resin, there are 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 examples as long as it can dissolve the molding special core and the main body, and it is needless to say that various solvents can be used. Alternatively, the same effect as that of the embodiment can be exhibited by performing it independently.

Further, the removal of the molding special core or the main body of the present invention is performed by using the residual heat alone or the combination of the residual heat and the heating of the embodiment, or by the heating alone or by the solvent such as the organic solvent. Not limited to those, if it is possible to effectively remove the molding special core or the main body, it goes without saying that other removal methods can be used, and many modified examples are possible,
The same effect as that of each embodiment can be obtained.

The molding method using the molding special core of the present invention is not limited to the die casting casting of the above-mentioned embodiment, and it is possible to further improve the quality of the cast product by adding a specific step to the die casting casting. The present invention is not limited to the embodiment, and many modifications can be considered.

Further, the present invention is not limited to the die casting of the above-mentioned embodiment, but can be applied to the sand type gravity casting method, the die gravity casting method, the low pressure casting method and the precision casting method, and other casting methods. Many modifications are conceivable, and the same effect as the above embodiment can be obtained.

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

That is, in the gravity casting method, since the molten metal residence time is long, the core-to-molten metal contact time is long, and the molten metal temperature is relatively high, the core must have both pressure resistance and heat resistance. However, by using the molding special core of the present invention, the heat capacity becomes large as compared with the conventional sand core and the synthetic resin core etc. of the present inventors' prior application. The core temperature rise is small, the heat resistance and pressure resistance are improved, the initial shape is retained without thermal deformation or pressure deformation, and it can contribute to the formation of desired molded products of a wide range of excellent quality.

That is, even when a cast product is obtained by the gravity casting method using the special molding core of the present invention, the intended cast product can be obtained in the same manner as in the above-mentioned embodiment.

In this case, the temperature of the molten metal depends on the cavity 5 of the mold 4.
Until the temperature reaches the initial temperature (for example, about 750 degrees C for molten aluminum), the core has a large heat capacity in combination with improved heat resistance and pressure resistance. The temperature rise of the core at the time is relatively small, the initial shape can be maintained without melting without thermal deformation or pressure deformation, and it can contribute to the formation of a wide variety of high-quality molded products, and casting products can be obtained efficiently. To be

[0132] The cast product prevents defects such as porosity and shrinkage from occurring, significantly reduces man-hours as compared with the conventional sand core, and becomes a cast product excellent in appearance quality and functional quality.

Further, the molding special core used in the method of the present invention is not limited to the molding special core of the embodiment, and many modifications are conceivable. Furthermore, a molding method other than casting is a plastic molding method. It can also be applied to a molding special core used in a ceramic molding method, can solve various problems as in casting, and can exhibit the same excellent effects as in the embodiment.

Further, 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, and the quality of molded products can be improved. However, the present invention is not limited to the above-described embodiment, and many modifications can be considered.

[0135]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, by molding with a specific molding method using a specific molding special core, the productivity is improved and the applicable range is expanded, and the molding is excellent in quality. The idea is to obtain a product, and it has the following excellent effects.

That is, when a molding core is used in which a part or all of the wall thickness of the molding core is formed to have a non-uniform thickness, the thin wall of the molding core is used when the pressurizing material is cooled. By deforming the forming part, it is possible to prevent defects such as deformation and damage of the molded product due to the influence of the pressurizing material and to contribute to the molding of the molded product of the target shape with the hollow shape and the undercut shape. You can In the conventional molding method such as casting, there was a problem such as deformation and damage of the molded product due to the influence of the pressure material during molding, but according to the method of the present invention, the deformation and damage of the conventional molded product It is possible to prevent defects such as die casting, and it is possible to easily mold even those with hollow shapes and undercut shapes that were impossible to mold such as die-cast casting, large shapes and complicated shapes, etc. Molding of all shapes and sizes is possible, the range of application is greatly expanded, design flexibility is improved, product performance is improved, productivity can be dramatically improved, and weight reduction etc. can significantly reduce costs. It has the advantage that it can be downsized and the quality of the molded product can be significantly improved.

In addition to this, the following effects can be obtained in a casting method such as die casting. (1) The high-pressure molten metal poured into the cavity in the mold is cooled to form a cast product having a desired shape, such as a hollow shape or an undercut shape. When the molten metal cools, a thin wall is formed. By deforming the part and creating a gap between it and the cast product, defects such as deformation and damage of the cast product due to the influence of molten metal, etc. are prevented, and a hollow shape or undercut shape is formed. There is an advantage that it can contribute to the casting of shaped castings. (2) In addition to facilitating the formation of hollow shapes and undercut shapes that are not possible with conventional die casting, it is also possible to create relatively large hollow parts or undercut parts of engine intake manifolds and exhaust manifolds. Shape can be formed by die casting, regardless of shape and size, it is possible to cast all shapes and sizes, and moreover, when cooling the molten metal after pressure pouring There is an advantage that it is possible to obtain a cast product such as a die-cast cast product having a target shape such as a hollow shape or an undercut shape by preventing defects such as deformation and breakage from occurring. (3) The molding core has both the non-disintegrating property during molding and the disintegrating property after molding, and the surface of the molding core is not as rough as the conventional sand core. Since it is smooth, the inner surface such as hollow shape or undercut shape is formed into a smooth surface, so secondary processing such as machining for inner surface smoothing is not necessary, and molded product defects such as wear and damage of molded products occur It is possible to improve the performance of the product using the molded product by preventing the above. (4) By using a special core, core molding is facilitated, molding equipment is simplified, the number of processes is reduced, the core is not easily broken, and it is easy to handle. There is an advantage that it is possible to reduce time and cost. (5) The main components can be prevented from permeating into the molded product, and defective products can be prevented by preventing the occurrence of defects such as blowholes and shrinkage or molten metal insertion due to the adverse effect prevention, thereby improving yield and productivity. (6) The core used in the present invention can be reused by reworking, which has the effect of reducing material costs and preventing pollution. (7) When using a core filled with a filler inside, the core is required to have conditions such as pressure resistance and heat resistance with the inside filled with a filler. Conditions such as pressure resistance and heat resistance are relaxed, the selection range of the core material can be expanded, and there is an advantage that the pressure resistance and heat resistance of the core can be adjusted by selecting the filling body. (8) When using a core filled with a filler, the hollow body is removed and lost by residual heat or heating and only the filler remains, so that the filler can be easily discharged and the core can be completely removed. There is an advantage that defects such as wear and damage of the product can be prevented.

The molding method using the special core for molding of the present invention is not limited to the die casting of the above-mentioned embodiment, but can be applied to gravity casting and other casting methods, as well as plastic molding, ceramic molding and other molding. Can also be applied to methods
The same excellent effects as the above-mentioned die casting casting and other casting methods can be obtained, it is possible to mold all shapes and sizes without being restricted by shape, the range of application is greatly expanded, and the degree of freedom in design is improved A wide range of molded products can be efficiently molded, productivity can be dramatically improved, and significant cost reductions can be achieved by reducing the weight, etc. Excellent quality with hollow shapes and undercut shapes. It is possible to efficiently obtain a molded product having a target shape.

[Brief description of drawings]

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

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

FIG. 4 is a vertical sectional view showing a first embodiment of a molding special core used in the first embodiment of the method of the present invention.

FIG. 5 is a transverse sectional view showing the molding special core.

FIG. 6 is a cross-sectional view showing a deformed state of the special molding core during molding.

FIG. 7 is a cross-sectional view showing a second embodiment of a molding special core used in the method of the present invention.

FIG. 8 is a cross-sectional view showing a third embodiment of a molding special core used in the method of the present invention.

FIG. 9 is a transverse cross-sectional view showing a fourth embodiment of a special molding core used in the method of the present invention.

FIG. 10 is a cross-sectional view showing a deformed state of the special molding core during molding.

FIG. 11 is a transverse sectional view showing a fifth embodiment of a molding special core used in the method of the present invention.

FIG. 12 is a sectional view corresponding to FIG. 2 of the second embodiment of the method of the present invention.

FIG. 13 is a vertical cross-sectional view showing a sixth embodiment of a special molding core for use in the second embodiment of the method of the present invention.

FIG. 14 is a cross-sectional view showing the molding special core.

FIG. 15 is a cross-sectional view showing a special molding core of a seventh embodiment used in the method of the present invention and an intake manifold which is a molded product.

FIG. 16 is a sectional view showing a special molding core and an exhaust manifold which is a molded product of an eighth embodiment used in the method of 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 (mold) (outer mold) 3 Lower mold (mold) (outer mold) ) 4 Mold (mold) (Plastic mold) (Ceramic mold) 5 Cavity (Casted product shape) (Plastic molded product shape) (Ceramic molded product shape) 6 Molded product (Casted product) (Plastic molded product) ( Ceramic molded product) S Hollow part (filling space) G Main body (heat resistant main body) H Filler N Local thin-wall forming part L Length of thin-wall forming part t Thickness of thin-wall forming part T Thickness of non-thin-wall forming part C Hollow shape U Undercut shape E Exhaust manifold I Intake manifold

Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location B28B 7/34 F B29C 33/54 9543-4F // B29C 33/14 9543-4F

Claims (24)

[Claims] 1. A molding core is formed of a non-sand core, a space is formed inside the molding core, and a part or all of the wall thickness of the molding core is formed. The shape of a molded product is obtained by using a special molding core having a non-uniform thickness and arranging the molding special core inside an outer mold such as a mold including an upper mold and a lower mold. By forming a mold having a hollow portion, a mold such as a plastic mold or a ceramic mold, and injecting a molding material such as pouring molten metal into the mold, a hollow shape or an undercut shape can be obtained. A molding method using a special molding core, which comprises molding a cast product such as a die cast product having a desired shape, or a molded product such as a plastic molded product or a ceramic molded product. 2. A molding material, etc., which is obtained by injecting a molding material into the molding die such as pouring molten metal under pressure, and then deforming a part of the molding special core when the molding material is cooled. A molding method using a special molding core according to claim 1, characterized in that the molding product is prevented from being deformed or damaged due to the influence of (1) and is molded into a target shape having a hollow shape or an undercut shape. . 3. A molded product such as a die cast product having a desired shape in which the hollow shape or the undercut shape is formed, or a molded product such as a plastic molded product or a ceramic molded product, and the molded product is then molded into the mold. 3. A molding core such as a plastic molding die, a plastic molding die, or a ceramic molding die, and the special core for molding is removed from the molded article by drawing, residual heat, heating, a solvent, or the like. Molding method using special core for molding. 4. The special molding core according to claim 3, wherein the special molding core is removed by drawing, residual heat, heating, solvent or the like alone or in combination thereof. Molding method. 5. A molding special core in which the entire thickness of the molding core is formed to have a non-uniform thickness, and molding is performed using the molding special core. Claim 1
A molding method using the special molding core according to claim 4. 6. A molding core, wherein a part or most of the wall thickness of the molding core is formed to have a non-uniform thickness,
A molding method using the special molding core according to any one of claims 1 to 4, wherein the molding is performed using the special molding core. 7. The molding core, wherein a part of the wall thickness of the molding core is a locally thin molding core, and molding is performed using the molding special core. A molding method using the special molding core according to claim 6. 8. The local thin-wall forming portion is a special molding core having a predetermined length that is thinly formed substantially uniformly, and molding is performed using the special molding core. A molding method using the special molding core according to claim 7. 9. The local thin-wall forming portion is a special molding core having a predetermined length that is nonuniformly thin, and molding is performed using the special molding core. A molding method using the special molding core according to claim 7. 10. The local thin-walled forming portion is a special molding core at one location, and the molding is performed using the special molding core. 9. A molding method using the molding special core according to any one of 9 above. 11. The local thin-walled forming portion is a special molding core at a plurality of locations, and molding is performed using the special molding core. 9. A molding method using the molding special core according to any one of 9 above. 12. The molding material comprising a non-sand core that satisfies both conditions of non-disintegration during molding (heat resistance) and disintegration after molding (heat disintegration property, solvent disintegration property, etc.). A special core, which is molded using the molding special core,
A molding method using the molding special core according to any one of claims 1 to 11. 13. The molding core according to claim 12, wherein the non-sand core is a molding special core made of a heat resistant material, and the molding is performed using the molding special core. Molding method using a special core. 14. The heat-resistant material is a molding special core made of heat-resistant rubber such as silicon rubber, and molding is performed using the molding special core.
A molding method using the described special molding core. 15. The molding according to claim 13, wherein the heat resistant material is a molding special core made of a synthetic resin (plastic), and the molding is performed using the molding special core. Molding method using a special core for use. 16. The synthetic resin (plastic) is a molding special core made of a thermosetting synthetic resin (thermosetting plastic), and molding is performed using the molding special core. A molding method using the molding special core according to claim 15. 17. The molding method according to claim 17, wherein the synthetic resin (plastic) is a special molding core made of a thermoplastic synthetic resin (thermoplastic), and the molding is performed using the special molding core. A molding method using the special molding core according to claim 15. 18. A molding special core made of a polycarbonate synthetic resin (polycarbonate plastic), wherein the thermoplastic synthetic resin (thermoplastic plastic) is molded by using the molding special core. A molding method using the special molding core according to claim 17. 19. The non-sand core is composed of a main body having a space formed therein and a filling body filled inside the main body, and moreover, a part or all of the thickness of the main body is Mold using a special molding core that has a non-uniform thickness,
A molding method using the molding special core according to any one of claims 1 to 18. 20. The molding core is made of a heat-resistant material such as powder, granules, or lumps, and the molding is performed using the molding special core. Item 19
A molding method using the described special molding core. 21. The heat-resistant material is a molding special core made of an inorganic material such as gravel of river, sea or mountain, and molding is performed using the molding special core. Claim 2
A molding method using the molding special core described in 0. 22. The molding special core according to claim 21, wherein the inorganic material is a molding special core made of ceramics, and the molding is performed using the molding special core. The molding method used. 23. The molding special core according to claim 21, wherein the inorganic material is a molding special core made of foundry sand, and molding is performed using the molding special core. Molding method using. 24. A molding special core in which the filling body is mixed with powdery, granular, or lumpy metal, and molding is performed using the molding special core. A molding method using the special molding core according to any one of claims 19 to 23.