JPH08174143A - Forming method using special forming core - Google Patents

Abstract

PURPOSE: To improve the heat resistance and pressure resistance of a special forming core, to improve the productivity, to reduce the cost, and to improve the quality of a formed article by achieving the pressurized pouring of the molten metal in a forming die while flowing the fluid in a core body. CONSTITUTION: An inlet 7 provided in an upper die 2 is matched with the inlet side of a tube P provided in a special forming core 1. An outlet provided in a lower die 3 is matched with the outlet side of the tube P provided in the special forming core 1. The special forming core 1 is arranged between the upper die 2 and the lower die 3 to form a die 4 having a hollow part 5. The molten metal such as the molten aluminum is poured into the hollow part 5 formed in the mold 4 by applying the pressure according to the material of the casting while continuously flowing the fluid in the tube P. Because the special forming core 1 is forcibly cooled by the continuous flowing of the fluid in the tube P, the heat resistance and pressure resistance against the molten metal are remarkably improved to eliminate the thermal deformation or pressure deformation.

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, by molding a special molding core using a specific molding method, the shape is not restricted. Obtaining cast products such as die-cast casting products with hollow shapes and undercut shapes, and plastic molded products and ceramic molded products, which enable efficient molding of a wide range of molded products. 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.

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, and there is a problem that the hollow portion and the undercut portion cannot be formed by the die casting.

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.

That is, the conventional casting using the sand core is
(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 10 steps is necessary.

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, or 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.).

[0012] After that, the present inventor continued further research,
A more suitable molding method using a special molding core has been clarified.

[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, by molding using a specific molding special core using a specific molding method, it is possible to easily form a hollow portion or an undercut portion, which has not been possible by conventional die casting, and further, the shape and size thereof can be formed. Regardless of the type, it is possible to cast all shapes and sizes, dramatically expand the range of application and dramatically improve productivity, and die cast casting that can dramatically improve quality by preventing adverse effects on cast products, etc. The casting method of

On the other hand, also in the case of plastic molding or ceramic molding, by molding by a specific molding method using a specific molding special core as in the above, the same as in the case of the casting method such as die casting In addition, it is possible to improve the productivity and expand the range of application, and to efficiently obtain a molded product having a desired shape with excellent quality.

[0016]

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.
When injecting a molding material into a molding die provided with the molding special core, a fluid such as a gas or a liquid is caused to flow through the core body, and a casting product such as a die cast casting product is produced by using the molding die. Molding molded products such as plastic molded products and ceramic molded products,
The present invention is achieved by providing 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, it is possible to easily form a hollow portion or an undercut portion, which is impossible by the conventional die-casting, by forming a specific molding core using a specific molding method. It is possible and can cast all shapes and sizes regardless of shape and size, greatly expands the range of application, dramatically improves productivity, and prevents adverse effects on cast products. It is possible to provide a casting method such as die casting, which can dramatically improve the casting temperature.

On the other hand, also in the case of plastic molding or ceramic molding, as in the case of the above-mentioned casting method such as die casting, the molding is performed by using a specific molding special core in the same manner as described above. In addition, it is possible to improve productivity and expand the range of application, and it is possible to efficiently obtain a molded product having a desired shape with excellent quality.

Moreover, according to the present invention, when the molding material is poured into the molding die, the molding product is molded while flowing the fluid such as gas or liquid into the core body. Since it is cooled and the heat resistance and pressure resistance to the molten metal are significantly improved, it is possible to maintain the initial shape without heat deformation or pressure deformation against high temperature and high pressure during molding, etc.Die cast with a hollow part and an undercut part The applicable range of cast products such as cast products and other molded products can be expanded, and the applicable range can be expanded to casting such as die-cast casting of all shapes and sizes, plastic molding, ceramic molding and other molding methods.

[0021]

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 relates to 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. Using a special core for molding, the core consists of a core body made of collapsible material such as river, sea, or mountain gravel, and an outer body that covers the surface (outer surface) of the core body. When forming a molding die such as a mold, a plastic molding die, or a ceramic molding die, and injecting a molding material into the molding die in which the molding special core is provided, a gas, a liquid, or the like is injected into the core body. A molding method using a special molding core, characterized in that a fluid is caused to flow and a molding product such as a die-cast casting product or a plastic molding product or a ceramic molding product is molded using the molding die. .

Then, the core is forcibly cooled, the pressure resistance at the time of injecting the molding material is improved, the pressure deformation is prevented to maintain the original shape of the core, and the heat resistance to the molding material is improved. As a result, thermal deformation can be prevented and the initial shape of the core can be maintained.

The molding special core used when molding the molded product such as the cast product, the plastic molded product or the ceramic molded product has non-disintegrating property (heat resistance and pressure resistance) at the time of molding and disintegration after molding. It is required to combine both conditions of heat resistance (heat disintegration property, solvent disintegration property, etc.).

Further, in order that the outer body constituting the molding core may satisfy the above conditions, non-disintegration property (heat resistance and pressure resistance) at the time of molding and disintegration property after molding (heat disintegration property or It is required to be a special molding core that has both conditions (solvent disintegration property, etc.).

Further, the core body constituting the special molding core is non-disintegrating (heat resistance and pressure resistance) with the outer surface of the outer surface covered during molding so as to satisfy the above conditions. ), And disintegrating property (heat disintegrating property, solvent disintegrating property, etc.) after molding is required.

Then, as shown in FIGS. 1 to 3, a special molding core is used to mold a molded product such as a cast product, a plastic molded product or a ceramic molded product.

Among the molding methods, the case where casting is carried out and the case where die casting is carried out will be explained as one of them.

That is, in this embodiment, die casting is performed 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 formed.
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 molding special core 1 which is a core is configured.

Inside the core body H, a pipe P is provided for cooling the molding special core 1 by flowing a fluid such as gas or liquid.

In the pipe P, the introduction side and the discharge side are formed substantially parallel to each other, and the introduction side and the discharge side are connected to each other at a substantially right angle, and the pipe P is integrally formed in a substantially U shape as a whole. ,
The fluid introduced from the introduction side flows through the pipe P and is discharged from the discharge side.

Second Step Next, as best shown in FIG. 1, the inlet side of the upper die 2 and the inlet side of the pipe P provided in the molding core 1 are introduced. The outlet hole 8 provided in the lower mold 3 and the discharge side of the pipe P provided in the special molding core 1 are matched to each other, and the special molding core 1 is moved to the upper mold 2 and the lower mold. 3 to form a mold 4 having a cavity 5.

Third Step Next, as shown in FIG. 1 and FIG. 2, while continuously flowing a fluid such as gas or liquid (compressed air in this embodiment) through the pipe P, the mold A molten metal such as an aluminum molten metal is poured into a hollow portion 5 formed inside the molten metal while pressure is applied depending on the material of the cast product.

At this time, as shown in FIG. 1 and FIG. 2, the fluid is introduced from the inflow hole 7 and the inflow side of the pipe P, is passed through the pipe P, and is discharged from the pipe P. By flowing out from the side and the outflow hole 8, the fluid is continuously flowed in the pipe P.

As a result, since the molding special core 1 is forcibly cooled by continuously flowing the fluid through the pipe P, the heat resistance and pressure resistance to the molten metal are remarkably improved. Also can retain the initial shape of the core without thermal or pressure deformation.

At this time, since the heat-resistant outer body G having excellent heat resistance is integrally formed on the surface of the core body H, the shape-maintaining function of the molding core 1 at the time of pouring is excellent and it is suitable for molten metal. The initial shape can be reliably retained without melting, and it can contribute to the molding of the molded product 6 having high dimensional accuracy and excellent quality.

Further, the injection temperature of the molding material such as molten metal is
By the time it reaches the cavity 5, the temperature drops considerably compared to the initial temperature (for example, about 660 degrees C for molten aluminum),
In addition, since the molding special core 1 has a large heat capacity and high heat resistance and pressure resistance, even if a high temperature due to the injection of the molding material acts, the core does not immediately melt and the initial shape of the core can be retained.

Therefore, the casting 6 having a shape corresponding to the shape of the cavity 5 is cast in a state in which the original shape is maintained without deforming the special molding core 1.

Fourth Step Subsequently, as best shown in FIGS. 2 and 3, the casting 6 formed as described above is taken out of the mold 4 to finish the casting.

The molding special core 1 contributes to the formation of the intended casting 6 by maintaining the shape during casting, and melts the outer body G by residual heat or heating of the casting 6 after casting. When the core body H is removed, the core body H becomes in an unrestrained state (free state), and the core body H can be discharged and removed to the outside of the cast product, and the special core 1 for molding in the cast product can be prevented from remaining.

In other words, when the special core 1 for molding is extracted or the outer body G is not removed sufficiently or is difficult or impossible due to residual heat, 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 or the shape of the molded product, in addition to residual heat and heating, a solvent, particularly an organic solvent, may be used together with residual heat or heating, or independently, from the outer body G, particularly synthetic resin. The outer body G can be dissolved and removed.

The pipe P which remains without being collapsed is
It can be taken out from the die cast casting 6 and reused.

Fifth Step Further, although illustration is omitted, a finished product can be obtained by removing unnecessary parts such as burrs of the cast product 6.

Therefore, as compared with the conventional casting method using sand cores, (1) core coating mold, (2) core drying, (3) sand removal of cast products, (4) sand of cast products Heat treatment (sand baking),
(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 the present invention will be described.

As described above, according to the molding method using the special molding core of the present invention, when the molten aluminum or the like is pressurized and poured into the cavity 5 in the third step, the special molding core 1 is used. Since the fluid is forcibly cooled by continuously flowing the fluid through the pipe P, the heat resistance and pressure resistance to the molten metal are significantly improved. Therefore, even when pouring the high-pressure molten metal, the core is not deformed by heat or pressure. The initial shape can be reliably retained.

Further, since the heat-resistant outer body G is integrally molded on the surface of the core body H, the special core 1 for molding at the time of pouring molten metal 1
The shape retention function is excellent, the initial shape can be retained more reliably without melting in the molten metal, and it can contribute to the molding of the molded product 6 having high dimensional accuracy and excellent quality.

Since the molding special core 1 is composed of the core body H made of a collapsible material and the outer body G made of a heat-resistant material for covering the surface of the core body H, the heat capacity of the molding core 1 is high. Since it is large and has high heat resistance and pressure resistance against injection of a molding material such as molten metal, the initial shape can be maintained without thermal deformation or pressure deformation even when the high-pressure material is injected during molding.

Further, the injection temperature of the molding material such as molten metal is
By the time it reaches the cavity 5, the temperature is lower than the initial temperature (for example, about 660 ° C. in the case of molten aluminum), the molding special core 1 depends on its own temperature and heat capacity.
It is possible to retain the initial shape of the core without immediately melting it against the high temperature effect due to the injection of the molding material.

Therefore, the casting 6 having a shape corresponding to the shape of the hollow portion 5 is cast in a state in which the original shape is maintained without deforming the special molding core 1.

As described above, a molding method using the special molding core of the present invention, even for those having a hollow portion or undercut, which has heretofore been impossible to die-cast, and those having a large shape or a complicated shape. According to the method, die casting is possible and easy.

Moreover, by improving the strength of the core, die casting of all shapes and sizes is possible without being restricted by the shape and size, the range of application is greatly expanded, the design flexibility is improved, and the product is Performance can be improved,
Furthermore, productivity can be dramatically improved, and the cost can be significantly reduced by reducing the weight.

Furthermore, according to the method of the present invention, the yield and the quality of the cast product can be dramatically improved by preventing the defect of the cast product such as the occurrence of a blowhole by eliminating the adverse effect on the cast product and improving the dimensional accuracy. Therefore, it is possible to efficiently obtain a molded product having excellent quality.

In the molded product 6 thus formed, the special molding core 1 has both conditions of non-disintegration at the time of molding and disintegration after molding, and Since the surface is smoother than the rough surface such as the conventional sand core, the inner surface such as the hollow portion and the undercut portion formed by the special molding core 1 is formed as a smooth surface without the 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, and the like. It is possible to improve the performance of products using.

Further, the casting method such as die casting can be achieved by drastically reducing the time and cost by drastically reducing the steps and greatly improving the yield.

Further, the molding method using the special molding core of the present invention is not limited to die casting, but sand sand gravity casting, metal die gravity casting, low pressure casting, precision casting, and other castings. Can be applied not only to the method, but also to other molding methods such as plastic molding, ceramic molding, etc., and the same excellent effects as those in the above-described examples can be obtained, and a molded product of a desired shape with excellent quality can be efficiently obtained. I can.

At this time, the molding special core 1 retains its shape due to its non-disintegrating property during molding and contributes to the formation of a desired molded product, and is disintegrated and eliminated by the disintegrating property after molding. Since no residue remains, it can contribute to the molding of a molded product having excellent quality such as smoothing the inner surface.

As described above, according to the method of the present invention, molded products having a wide range of shapes can be efficiently molded without being restricted by the shape, and a cast product, a plastic molded product or a ceramic having a hollow shape or an undercut shape is formed. It is possible to obtain molded products such as molded products.

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

4 to 6 show a first embodiment of a method for forming a special molding core according to 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 in which the pipe P is arranged first, and then forming the outer body G on the surface (outer surface) of the core body H. The second is In this method, the outer body G is formed first, and then the pipe P is provided inside the outer body G and a collapsible material such as gravel of a river, sea or mountain is filled.

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, after a pipe P for flowing and cooling a fluid is first arranged, a shirasu, which is a mountain gravel as an inorganic material, is provided around the pipe P. Is hardened with glue to form a core body H having a predetermined shape.

At this time, the introduction side and the discharge side of the pipe P are formed substantially parallel to each other, and the introduction side and the discharge side are connected to each other at a substantially right angle, and the pipe P is formed in a substantially U-shape as a whole. The fluid introduced from the introduction side flows through the inside and is discharged from the discharge side.

Subsequently, as well shown in FIG. 5, a polycarbonate synthetic resin, which is a heat-resistant synthetic resin, is formed to a predetermined thickness on the surface of the core body H to form a heat-resistant outer body. The outer body G is formed.

In this way, it is possible to form the molding special core 1 having the predetermined shape in which the pipe P is arranged inside the core body H and the heat resistant outer body G is formed on the surface of the core body H.

When molding is performed by using the molding special core 1, the strength is improved, the breakage is prevented, and the handling is easy, and the molding is possible regardless of the shape or size. Therefore, the applicable range can be expanded and the productivity can be improved, and a molded product having excellent quality can be efficiently obtained.

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 well in FIG. 6, a polycarbonate synthetic resin is formed in a predetermined shape with a predetermined thickness to form a heat-resistant outer body having a hollow filling space S inside. The outer body G is formed.

Next, as well shown in FIG. 5, a pipe P having a predetermined shape is arranged in the filling space S of the outer body G, and a shirasu, which is a gravel of a mountain, is arranged around the pipe P. It is filled and hardened with glue to form a core body H having a predetermined shape.

At this time, the introduction side and the discharge side of the pipe P are formed substantially parallel to each other, and the introduction side and the discharge side are connected to each other at a substantially right angle, and the pipe P is formed in a substantially U shape as a whole. The fluid introduced from the side flows through the inside and is discharged from the discharge side.

In this way, the pipe P is disposed inside the core body H, and the heat-resistant outer body G is formed on the surface of the core body H to form the special molding core 1 having a predetermined shape.

When the molding and molding is performed by using the molding core 1, the strength is improved, the breakage is less likely to occur, and the handling is easy, as in the first embodiment. Molding is possible regardless of the shape or size, the application range can be expanded, productivity can be improved, and a molded product with excellent quality can be efficiently obtained.

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

Further, the special molding core of the present invention is not limited to the above-described embodiment, but can be applied to various shapes using various special molding cores to improve the quality of molded products. The present invention is not limited to the above embodiment, and many modified examples 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 of various materials, and the quality of molded products can be improved.

That is, the molding special core 1 of the present embodiment.
Has both the non-disintegrating property (heat resistance and pressure resistance) at the time of molding and the disintegrating property after molding (heat disintegrating property, solvent disintegrating property, etc.) and generates a large amount of gas at the time of molding. It is required to have no adverse effect on the molded product.

At the time of molding, the core body H which constitutes this molding special core 1 satisfies the above conditions.
It is necessary that the outer body G has the non-disintegration property while the surface is covered, and the disintegration property is provided after molding.

As the core body H satisfying this condition,
For example, there is a core body H formed from a collapsible material such as an inorganic material such as gravel of river, sea or mountain.

Among them, the inorganic materials include the river gravel, the sea gravel, and the mountain gravel.

Further, as the inorganic material satisfying the above-mentioned conditions, there are raw molding sand itself containing no binder, hardening agent, etc., and powdery, granular or lumpy ceramics (new ceramics or old ceramics). .

The core body H may be made of gravel, foundry sand, ceramics or the like, or may be mixed with powdery, granular or lumpy metal.

Examples of this metal include iron such as iron oxide, aluminum such as aluminum oxide, and other metals.

Furthermore, the core body H 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, and the quality of molded products such as cast products. Many modifications are conceivable, and the same effects as those of the above embodiments can be obtained.

On the other hand, the outer body G constituting this molding special core 1 maintains its original shape without melting at the high temperature at the time of molding so as to satisfy the above conditions, and the core body H is enclosed inside. It is required that the core body H be completely protected against gas generation from the special molding core 1 even if gas is generated in the core body H, and there is no adverse effect on the molded product such as generation of a large amount of gas during molding. It

Therefore, the outer body G is required to satisfy both the above-mentioned conditions and both the non-disintegration property during molding and the disintegration property after molding.

Examples of the outer body G that meets the conditions include synthetic resins (plastics) and other materials. Among them, the synthetic resins include the following.

That is, a synthetic resin as a material satisfying the above conditions is, for example, a thermoplastic synthetic resin (thermoplastic), which has both of the above conditions.
It is possible to obtain a molded product that sufficiently satisfies the initial purpose.

Further, among the thermoplastic synthetic resins, the most suitable one is the polycarbonate synthetic resin of the above-mentioned embodiment, which satisfies all the above conditions, and is a cast product which sufficiently satisfies the intended purpose. Other molded products can be obtained.

Next to this, there are fluororesins (polyfluoroethylene resins) such as tetrafluoroethylene resin, polyimide resins, polyamide-imide resins and polysulfone resins, which satisfy all of 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 (Tetoron resin), which have both of the above conditions, and a molded product satisfying the initial purpose can be obtained.

Further, the synthetic resin used for the outer body G of the present invention is not limited to the above-mentioned synthetic resin, and both conditions of non-disintegration at the time of molding and disintegration after molding are provided, and special synthetic molding Needless to say, thermoplastic synthetic resins, thermosetting synthetic resins, and other synthetic resins other than those in the above examples can be used as long as they can completely prevent gas generation from the child 1 and do not adversely affect the molded product. It is possible to obtain the same effect as in the above embodiment.

Further, it goes without saying that the material is not limited to the synthetic resin material, and other materials can be used as long as these conditions are satisfied.

Other materials satisfying the above conditions include heat-resistant synthetic rubbers, rubbers such as silicon rubbers and fluorine rubbers. For example, heat-resistant rubbers such as silicon rubbers can be mentioned, 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 of the outer body G, as long as the above conditions are satisfied, other than the above synthetic resins and rubbers, low melting metals such as tin, lead and antimony, ceramics, and other single materials can be used. In addition to the material, FRR
(Fiber reinforced rubber), FRP (fiber reinforced plastic), GFRP (glass fiber reinforced plastic) and other composite materials can be used, and external bodies made of various materials are conceivable. Obtainable.

Further, the molding special core used in the present invention is not limited to the materials and shapes of the above-mentioned embodiment, but can be applied to various shapes using various materials, such as cast products. It is possible to improve the quality of the molded product, and many modifications are conceivable, and it is possible to obtain the same effects as those of the above embodiments.

Further, the outer body G of the present invention is not limited to the materials and shapes of the above-mentioned embodiments, and many modifications can be considered, and the same effects as those of the above-mentioned embodiments can be obtained.

Furthermore, the molding special core of the present invention is not limited to the materials and shapes of the above-mentioned examples, but can be applied to various shapes using various materials, and can be used for moldings such as castings. It is possible to improve the quality and the like, and many modifications are conceivable, and the same effects as those of the above-described embodiments can be obtained.

The removal of the outer body G for satisfying the disintegration property after molding (heat disintegration property, solvent disintegration property, etc.) is basically dissolved and eliminated by the residual heat of the molded product 6, but Depending on the shape and shape of the molded product, it melts due to the residual heat of the molded product 6,
It can be dissolved and removed by heating or a solvent, especially an organic solvent.

That is, in the case where the special core 1 for molding is taken out or the outer body G is not removed due to residual heat or is 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 in combination or by 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 together with the residual heat or heating, or alone 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 among thermoplastic synthetic resins, normal alkylbenzene (trade name "Nonion" etc.) can be sufficiently satisfied from the viewpoint of function and cost, and in actual use, There was no problem.

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 goes without saying that various solvents can be used. If it is carried out independently, the same effect as in the above embodiment can be exhibited.

Further, the removal of the outer body G of the present invention is not limited to the removal of the residual heat of the above-mentioned embodiment alone or the combination of the residual heat and the heating, or the heating alone or the solvent such as the organic solvent. Of course, as long as the G can be effectively removed, it is needless to say that other removal methods can be used, and many modified examples are conceivable, and the same effects as those of the above-described respective embodiments can be obtained. .

The molding method using the special molding core of the present invention is not limited to the die casting casting of the above-mentioned embodiment, but 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 embodiments, 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 longer than other casting methods, the contact time with the molten metal is long, and the molten metal temperature is relatively high, the core has a non-disintegrating property during molding. However, by using the molding special core of the present invention, the specific heat is large as compared with the conventional sand core or the core made of the synthetic resin previously filed by the present inventor. Since the heat capacity becomes large, the temperature rise of the molding special core during pouring the molten metal is small, the heat resistance and pressure resistance are improved, the initial shape is retained without thermal deformation or pressure deformation, and the quality is excellent. It can contribute to the formation of a desired cast product that is a wide range of molded products.

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.

At this time, in the gravity casting method, the molten metal residence time is long, the contact time between the core and the molten metal is long, and the temperature of the molten metal is relatively high. Therefore, the core has both pressure resistance and heat resistance. It is necessary to use a special molding core 1, and the core is forcibly cooled by molding the molded product while continuously flowing a fluid inside the core, so that heat resistance and pressure resistance are achieved. It can be improved and the initial shape can be maintained without thermal deformation, which can contribute to the intended formation of a cast product.

In this case, the temperature of the molten metal depends on the cavity 5 of the mold 4.
By the time the temperature reaches, the temperature drops below the initial temperature (for example, about 750 degrees C for molten aluminum), the core
Combined with the decrease in temperature due to forced cooling with a fluid and the improvement in heat resistance and pressure resistance, the heat capacity increases, so the temperature rise of the core during pouring is relatively small and the core melts without thermal or pressure deformation. The initial shape can be maintained without being involved, and it is possible to contribute to the formation of a wide variety of molded products of excellent quality, and cast products can be obtained efficiently.

[0125] The cast product prevents defects such as porosity and shrinkage from occurring, significantly reduces man-hours as compared with the conventional sand core, and is a cast product excellent in appearance quality and functional quality.

As described above, even in the gravity casting method, the molding special core 1 contributes to the formation of a desired casting product by maintaining the shape during casting, and after casting, the outer body G is heated by residual heat or heating of the casting product. Melted and completely removed and disappeared, and the core body H that was in an unrestrained state (free state) due to the disappearance of the outer body was completely removed to form the cast product 6, which facilitates complete removal and wear of the product. It is possible to prevent defects such as damage and damage, improve the quality of cast products, improve yield, save time and money, and improve productivity.

Further, the special molding core used in the present invention is not limited to the special molding core used in the casting of the above-mentioned embodiment, and many modifications are conceivable. It can also be applied to a molding special core used in a plastic molding method or a ceramic molding method, which can solve various problems as in the case of the above-described casting, and can exhibit the same excellent effects as those in the above-mentioned examples. .

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.

The present invention as described above has the following effects.

As described above, according to the molding method using the molding special core of the present invention, the molding special core is forcibly cooled by continuously flowing the fluid such as gas or liquid through the pipe during molding. Therefore, the heat resistance and pressure resistance of the special molding core are significantly improved, so that the initial shape of the core can be retained without thermal deformation or pressure deformation, and hollow parts that were previously impossible to mold such as die casting. Even those with undercuts, large shapes, and complicated shapes can be easily molded by die casting, etc., the range of application is greatly expanded, design flexibility is improved, and product performance is improved. It is possible,
Further, the productivity can be dramatically improved, and further, the cost can be greatly reduced by reducing the weight, and the quality of the molded product can be improved.

Since the molding special core used in the method of the present invention is composed of the core body and the outer body, it has a large heat capacity and is resistant to heat and pressure against injection of a molding material such as molten metal. Therefore, the initial shape can be maintained without being deformed by heat or pressure when the high-pressure material is injected at the time of molding, and it is possible to contribute to the molding of a molded product having high dimensional accuracy and excellent quality.

Further, according to the method of the present invention, it is possible to improve the yield and improve the quality of the cast product by preventing the occurrence of defects in the cast product such as the occurrence of blowholes by eliminating the adverse effects on the cast product and improving the dimensional accuracy. It is possible to efficiently obtain molded products of excellent quality.

Since the molded product formed by the method of the present invention has a smooth core surface, the inner surface of the molded product, such as the hollow portion and the undercut portion, is formed into a smooth surface without a rough surface. Subsequent processing is unnecessary, occurrence of defects in the molded product such as wear and damage of the molded product can be prevented, and the performance of the product using the molded product can be improved.

Further, according to the method of the present invention, it is possible to improve the productivity and expand the range of application even in the case of plastic molding or ceramic molding, and efficiently obtain a desired molded article of excellent quality. be able to.

According to the method of the present invention, the core molding is easy, the molding equipment is simplified and the steps are reduced, and the time and cost are reduced and the handling is facilitated. Further, the transportation and storage are facilitated, and the molding process is easy. There are various effects such as reduction of man-hours such as unnecessary pressure adjustment.

The method 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.

FIG. 7 shows a second embodiment of the molding method using the special molding core of the present invention.

In this embodiment, similarly to the first embodiment, a pipe P for flowing a fluid such as gas or liquid is provided in the core body H. Unlike the example, the pipe P disposed in the core body H is an introduction pipe P1 having a tip opening for introducing a fluid, and the fluid introduced into the core body H is discharged to the outside of the core body H. And a discharge pipe P2 having an opening at the tip.

As a result, as in the first embodiment, when the molten metal such as the aluminum molten metal is poured under pressure into the hollow portion 5 in the mold 4, it is introduced into the introduction pipe P1, the discharge pipe P2 and the core body H. Forced cooling is performed by continuously flowing a fluid such as gas or liquid.

At this time, unlike the first embodiment, since the fluid not only flows through the pipe but also diffuses in the core body H,
Cooling effect is better, heat resistance and pressure resistance are also significantly improved,
Even when pouring high-pressure molten metal, the initial shape of the core can be maintained without thermal deformation or pressure deformation.

Therefore, the high-quality cast product 6 having a shape corresponding to the shape of the cavity 5 can be efficiently cast by die casting or the like in the original shape maintaining state without deforming the special molding core 1.

Further, the method of the present invention can be applied not only to die casting but also to sand type gravity casting method, die gravity casting method, low pressure casting method, precision casting method and other casting methods. In addition to obtaining the same excellent effects as the above example, it can also be applied to other molding methods such as plastic molding and ceramic molding, the same excellent effects as the above example can be obtained, and a molded product of the desired shape with excellent quality can be obtained. It can be obtained efficiently.

FIG. 8 shows a third embodiment of the molding method using the special molding core of the present invention.

In this embodiment, similarly to the second embodiment, the introduction pipe P1 for continuously flowing the fluid into the core body H and the discharge of the introduced fluid to the outside of the core body H. The molding special core 1 is configured by arranging the discharge pipe P2 and the discharge pipe P2. However, unlike the second embodiment, the strainer F is provided at the open end of the discharge pipe P2. The fluid in the core body H is filtered by F and the discharge pipe P is used.
Introduce into 2 and discharge.

As a result, similar to the second embodiment, when the molten metal such as the aluminum molten metal is pressurized and poured into the cavity 5, the introduction pipe P1, the discharge pipe P2 and the core body H are filled with the gas or liquid. Forced cooling is achieved by continuously flowing a fluid.

Therefore, similarly to the second embodiment, the fluid not only flows through the pipe but also diffuses in the core body H, so that the cooling effect is further improved, and the heat resistance and pressure resistance are remarkably improved.
Even when pouring high-pressure molten metal, the initial shape of the core can be maintained without thermal deformation or pressure deformation.

At this time, unlike the second embodiment, the strainer F is provided at the opening end of the discharge pipe P2, and the strainer F
Since the fluid is filtered and introduced into and discharged from the discharge pipe P2, the clean fluid is more reliably introduced into the discharge pipe P2.

Therefore, it is possible to efficiently cast a high-quality 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.

Further, the method of the present invention is not limited to die casting, but can be applied to sand type gravity casting method, die gravity casting method, low pressure casting method, precision casting method, and other casting methods. In addition to obtaining the same excellent effects as the examples, it can be applied to plastic molding, ceramic molding, and other molding methods, and the same excellent effects as the above examples can be obtained, and molded products of the desired shape with excellent quality. Can be obtained efficiently.

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.

[0151]

As described above, according to the present invention, by molding by a specific molding method using a specific molding special core,
The idea is to improve the productivity and expand the range of application, and to obtain a molded product with excellent quality, which has the following excellent effects.

That is, since the molding special core is composed of the core body and the outer body, and the fluid is continuously flowed during the molding for forced cooling, the heat resistance and pressure resistance of the molding special core are improved. The core can retain its initial shape without being deformed by heat or pressure, and it has a hollow part or undercut that could not be molded by die casting, etc., or has a large shape or a complicated shape. In addition, molding can be performed easily, and all shapes and sizes can be molded, which greatly expands the range of application, improves design flexibility, improves product performance, and dramatically improves productivity. In addition, there is an advantage that the cost can be significantly reduced by reducing the weight and the quality of the molded product can be remarkably improved.

In addition to this, the following effects can be obtained in a casting method such as die casting. (1) Since the molded product is formed by continuously flowing a fluid such as gas or liquid inside the core, the core is pressure-resistant while continuously flowing a fluid such as gas or liquid inside. Since it is sufficient to satisfy the conditions such as the heat resistance and the heat resistance, the conditions such as the pressure resistance and the heat resistance required for the core are alleviated, and there is an advantage that the selection range of the core material can be expanded. (2) There is an advantage that the pressure resistance and heat resistance of the core can be adjusted by adjusting the flow rate and the fluid temperature of the fluid such as gas or liquid that is continuously flown inside the core. (3) By using a special core as the core, there are advantages that the molding of the core is facilitated, the molding equipment is simplified, the process is reduced, and the time and cost can be reduced. (4) There is an effect that the main body component is prevented from permeating the molded product with the outer body, and the defective product is prevented by preventing the occurrence of defects such as the occurrence of a porosity due to the adverse effect prevention, thereby improving the yield and the productivity. (5) Since it is molded with a special molding core that has a smoother surface and superior strength compared to conventional sand cores, defects such as porosity and shrinkage are prevented, casting defects are prevented, and machining is performed. Since no post-treatment is required, the surface can be smoothed and the quality can be improved. (6) By obtaining a molded product by this molding method, it is possible to make the wall thickness thinner than the conventional sand core, and it is possible to reduce the weight and the cost. (7) By obtaining a molded product by this molding method, the dimensional accuracy is improved as compared with the conventional sand core, post-treatment such as machining is unnecessary, and the number of steps can be reduced. (8) By obtaining a molded product by this molding method, it is possible to freely adjust the pressure resistance and heat resistance of the core by selecting the material and amount. (9) By obtaining a molded product by this molding method, the core is less likely to be broken, is easy to handle, and is easy to transport and store, thus reducing man-hours and time and cost. (10)
In the present molding method, a core having both the non-disintegrating property during molding and the disintegrating property after molding is used as a contradictory condition, and it is possible to prevent the occurrence of defects in the molded product such as molten metal insertion. (11) Since the core used in the present molding method does not contain a difficult-to-remove component and has a disintegrating property after molding, it can be easily removed and pollution can be prevented, and the time and cost can be reduced. (12) The core used in this molding method can be reused by reprocessing the core body discharged by melting the outer body,
This has the effect of reducing material costs.

On the other hand, also in the case of plastic molding or ceramic molding, the method of the present invention has the effect of efficiently obtaining a desired molded article of excellent quality.

Further, according to the method of the present invention, even in the case of plastic molding or ceramic molding, the core molding is easy and the molding equipment is simplified. Since the cost can be reduced and the man-hours required for adjusting the pressure at the time of molding can be reduced, the productivity can be improved and the scope of application can be expanded.

[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 obtained by the molding method using the special molding core according to the first embodiment of the present invention.

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

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

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

FIG. 7 is a sectional view corresponding to FIG. 2 of the second embodiment of the present invention.

FIG. 8 is a sectional view of a third embodiment of the present invention, which corresponds to FIG.

[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 hollow part (shape of cast product) (shape of plastic molded product) (shape of ceramic molded product) 6 molded product (cast product) (plastic molded product) (ceramic molded product) 7 inflow hole 8 outflow hole P pipe P1 introduction pipe P2 Discharge pipe F Strainer G Outer body (heat resistant outer body) H Core body S Filling space

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location B22D 18/04 L 29/00 F B29C 33/52 9543-4F

Claims (19)

[Claims] 1. A molding core comprises a core body made of a collapsible material such as gravel of river, sea or mountain, and an outer body covering the surface (outer surface) of the core body. In addition, a mold, a plastic molding die, or a ceramic molding die is formed by using a molding special core in which a flow path for flowing a fluid such as gas or liquid is provided in the core body. When a molding material is formed into a molding die in which the molding special core is provided and the molding material is injected into the molding die, the molten metal is poured into the molding die while flowing a fluid such as gas or liquid into the core body. By injecting a molding material, such as by pouring molten metal under pressure, a molded product such as a die-cast molded product having a hollow shape or an undercut shape, or a molded product such as a plastic molded product or a ceramic molded product is molded. ,
A molding method using a special molding core. 2. A method of injecting a molding material such as pouring molten metal into the molding die, and then cooling the molding material,
The molding method using the special molding core according to claim 1, wherein the molding is performed to 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. 2. The molding core is removed from a molding die such as a plastic molding die or a plastic molding die, and then the special core for molding is removed from the molded article by drawing, residual heat, heating, a solvent, or the like. A molding method using the special molding core according to 2. 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 fluid such as a gas or a liquid is caused to flow through the core body by flowing the fluid through a flow path in a pipe arranged in the core body. A molding method using the special molding core according to any one of claims 1 to 4. 6. A fluid such as a gas or a liquid is caused to flow into the core body by introducing the fluid into the core body from a flow path of an introduction pipe provided in the core body and opening the core body. 5. The molding according to any one of claims 1 to 4, wherein the fluid in the main body is introduced and discharged into a channel of a discharge pipe opened in the core body. Molding method using a special core. 7. A strainer is provided at the opening end of the discharge pipe opened in the core body, and the strainer filters the fluid in the core body and introduces it into the flow path of the discharge pipe. 7. The molding method using the molding special core according to claim 6, wherein the molding core is discharged. 8. A molding core is provided with both conditions of non-disintegration during molding (heat resistance and pressure resistance) and disintegration after molding (heat disintegration, solvent disintegration, etc.). It is a special molding core, and it molds using this special molding core, The molding method using the special molding core according to any one of claims 1 to 7. 9. A core body made of a collapsible material is a core body made of an inorganic material such as gravel of a 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 any one of claims 1 to 7, wherein 10. The molding special according to claim 9, 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. 11. The molding special core according to claim 9, 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. 12. A molding special core having a core body mixed with a metal in the form of powder, granules, lumps or the like, and molding is performed using the molding special core. Claim 1
A molding method using the special molding core according to claim 11. 13. A molding comprising an outer body having both conditions of non-disintegration during molding (heat resistance and pressure 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 12. 14. The molding special core according to claim 13, 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. Molding method using a child. 15. The molding special core according to claim 14, wherein the heat resistant outer body is a molding special core made of a synthetic resin, and the molding is performed using the molding special core. Molding method using a child. 16. The molding special core according to claim 15, wherein the synthetic resin is a molding special core made of a thermosetting synthetic resin, and the molding is performed using the molding special core. Molding method using a core. 17. The molding special core according to claim 15, wherein the 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 child. 18. 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. 19. The heat-resistant outer body is a molding special core made of heat-resistant rubber such as silicone rubber, and the molding is performed using the molding special core. Molding method using special core for molding.