JPH071079A - Special molding core - Google Patents

Abstract

PURPOSE:To provide a special molding core capable of efficiently obtaining a molded product having excellent quality and comprehensive shape without being restricted by the shape by using the special core. CONSTITUTION:After forming the special molding core 1 having a flow passage S in the inner part, the special molding core 1 is arranged between an upper die 2 and a lower die 3 to form a die 4 being one of the molding dies. Then while continuously charging fluid such as gas or liquid into the flow passage S, molten metal such as molten aluminum is poured into a cavity part formed in the die 4 in accordance with the material of a cast product 6. Successively, after molding the cast product 6 having the shape corresponding to the shape of the cavity part, the cast product 6 is taken out from the die 4. By removing the unnecessary part such as casting flash of the cast product 6, the molded product having excellent quality and comprehensive shape is efficiently obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a special core for molding, and in particular, by using a special core without using a sand core which has been conventionally generally used as a core, Expanded selection range and enabled efficient formation of molded products in a wide range of shapes without being restricted by shape. Hollow shapes and undercut shapes etc. are cast products, plastic molded products and ceramic molded products. The present invention relates to a special molding core used for forming a molded product such as.

[0002]

2. Description of the Related Art Molding by molding methods such as casting adopted as a part of machine work, injection molding adopted as a part of plastic molding, and injection molding adopted as a part of ceramic molding In order to form a hollow portion or an undercut portion, a product has heretofore been molded using a non-disintegrating core or a disintegrating core to obtain the molded product.

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

As the latter (disintegratable core), a sand core is generally used in casting for obtaining a cast product among the above-mentioned molded products, but it is difficult to mold and easily disintegrates. Not only is it difficult to handle, but it is also difficult to meet the conflicting conditions of pressure resistance during casting and disintegration after casting.

Therefore, in recent years, in the casting, it has been proposed to obtain a cast product by casting using a core having a special coating on the surface of the sand core. However, I could not solve the problem. (1) The coating is difficult because it is difficult to form not only one layer but also a plurality of layers. Therefore, not only the coating is time-consuming and labor-intensive, but also time and cost are required. It is difficult to achieve the initial purpose. (2) Since it is difficult to completely remove the binder that is a component of the coating layer and the sand core after molding, it is necessary to perform a sand baking treatment to remove the coating layer and the binder. It is time-consuming and costly. (3) Since the sand core is difficult to mold, it requires not only equipment and man-hours, but also the molded sand core is fragile and difficult to handle, and it requires man-hours and yield is poor.
It takes time and money. (4) Sand core requires complicated pressure adjustment to prevent collapse during casting, and complete collapse after casting is difficult. Therefore, heat treatment step, sand drop step, and sand drop inspection are necessary. Therefore, it requires man-hours, time and cost. (5) It is easy to generate defective products such as a molten metal being inserted between sand particles of a core during casting, and a component of the sand core penetrating into a cast product to cause a cavity in the cast product, Casting yield is poor and productivity is poor. (6) It is difficult to completely remove the core sand after casting, and it adheres to the cast product, causing problems such as wear and damage of the product. (7) Casting of complicated shapes and large castings are difficult or virtually impossible to cast, so the range of application is limited,
There is a problem in design and production. (8) When the sand of the sand core is reused after casting, it is difficult to completely remove the coating layer and the binder because the coating layer and the binder are contained in the sand core. Then
It takes time and money. (9) The sand core has many defects such as difficulty in molding, easy to collapse, and difficult to handle, and it is difficult to satisfy the conflicting conditions of pressure resistance during casting and disintegration after casting. It requires many steps as described below, the yield is low, and it takes time and cost.

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

[0007] Further, in the same way as the above-mentioned casting, various molded articles can be molded by a molding method such as injection molding adopted as a part of plastic molding or a molding method such as injection molding adopted as a part of ceramic molding. There was a problem.

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

[0009]

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

That is, for example, in casting for obtaining a cast product among the above-mentioned molded products, (1) by using a special core, the conditions such as pressure resistance and heat resistance required for the core are alleviated. , Expand the selection range of core materials. (2) The pressure resistance and heat resistance of the core are adjusted by adjusting the flow rate and the fluid temperature of a fluid such as gas or liquid that is continuously flown into the core. (3) By using a special core that is not easily broken,
The core is easy to mold and handle, reducing man-hours and time and cost. (4) By using a special core that does not use a penetrating component such as a binder, it is possible to prevent the core component from penetrating into the cast product, thereby preventing the occurrence of defects such as porosity. , It is possible to prevent the generation of defective cast products, which contributes to the improvement of yield and the improvement of productivity. (5) By using a core that has the conflicting conditions of pressure resistance during molding and heat dissipation after molding, problems such as molten metal insertion during molding can be avoided and pressure resistance (non-collapse) The heat dissipation of the core after molding and the complete removal of core components are facilitated, and adhesion to the molded product is prevented, resulting in the occurrence of molded product defects such as wear and damage of the molded product. Block. (6) The use of a special core facilitates the formation of hollow parts and undercut parts, and improves core strength,
Expanding the range of application by enabling casting of all shapes and sizes without being bound by shapes and sizes. (7) The special core does not contain binders and other difficult-to-remove components, which facilitates complete collapse and removal of the core after casting, simplifies reuse, prevents pollution, and reduces man-hours. Save time and money.

In addition, various molding methods such as injection molding adopted as a part of plastic molding and molding methods adopted such as an injection molding adopted as part of ceramic molding can be used. The problem can be solved.

[0012] For example, the core is formed by continuously flowing a fluid such as a gas or a liquid into the core to obtain a desired molded product, thereby significantly expanding the range of material selection. Therefore, the core molding becomes easy, the cost can be reduced, and the like, so that the various problems described above can be solved.

[0013]

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 cast product, a plastic molded product or a ceramic molded product. A molding core for forming the molding core from a non-sand core, and for molding while continuously flowing a fluid such as a gas or a liquid inside the molding core. This is achieved by providing a special molding core, characterized in that it is provided with a flow channel.

[0014]

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

That is, according to the present invention, by using a special core as the core, it is possible to improve the productivity and expand the range of application, and to efficiently obtain a molded product of excellent quality. , For example, in the case of a molding special core for casting to obtain a casting among the molding special cores used to form the molded product such as the above-mentioned cast product, plastic molded product or ceramic molded product, (1) Since the molded product is manufactured while continuously flowing a fluid such as gas or liquid inside the core, the core is pressure-resistant with the fluid such as gas or liquid continuously flowing 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 relaxed, and the selection range of the core material can be expanded. (2) The pressure resistance and heat resistance of the core can be adjusted by adjusting the flow rate and the fluid temperature of a fluid such as gas or liquid that is continuously flown into the core. (3) By using a special core as the core, molding of the core is facilitated, molding equipment is simplified, the number of steps is reduced, and time and cost can be reduced. (4) Since a special core is used as the core, it does not break even if dropped or thrown, so handling is easy, and man-hours such as easy transportation and storage are reduced, and time and cost can be reduced. it can. (5) Since the special core used does not contain a permeation component such as a binder, the core component is prevented from permeating into the molded product, which prevents defects such as porosity from occurring. The generation of defective products can be prevented, and the yield and productivity can be improved. (6) By using a special core as the core, it becomes easy to form the hollow part and the undercut part, and the core strength is improved. It is possible to mold the ridge and expand the range of application. (7) By using a core that has the conflicting conditions of pressure resistance during molding and heat dissipation after molding, problems such as molten metal insertion during molding can be avoided and pressure resistance (non-collapse) The heat dissipation of the core after molding and the easy removal of core components are prevented, and the adhesion to the molded product is prevented, and the occurrence of molded product defects such as wear and damage of the molded product is prevented. Can be achieved. (8) Since the special core does not contain components such as a binder that are difficult to remove and has heat dissipation after molding,
Complete removal of the core is facilitated, the occurrence of pollution can be prevented, the number of steps is reduced, and the time and cost can be reduced.

Further, even when a molded product is obtained by a molding method such as injection molding adopted as a part of plastic molding or a molding method such as injection molding adopted as a part of ceramic molding, the above-mentioned molding special core is used. By using, the intended molded product can be obtained, and a molded product having excellent quality can be efficiently obtained.

According to the above construction, the productivity can be improved and the range of application can be increased. By using the special molding core as in the above casting, the molding of the core becomes easy. , Simplification of molding equipment, reduction of process steps, reduction of time and cost, easy handling, easy transportation and storage, and no need for pressure adjustment during molding. There are various actions such as reduction of man-hours and reduction of time and cost.

[0018]

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

1 to 4 show a first embodiment of a special molding core of the present invention.

That is, the present invention does not use a sand core, which is generally widely used as a core, and is generally considered to be difficult or unusable. It is a special molding core characterized by forming a hollow shape or an undercut shape into a molded product such as a cast product, a plastic molded product or a ceramic molded product by using a core.

In the present invention, a non-sand core is used as the molding special core to form a molding die such as a mold, a plastic molding die or a ceramic molding die, and the molding die is used. A molded product is manufactured.

Further, in the present invention, a flow path for molding while continuously flowing a fluid such as gas or liquid is provided inside the molding special core.

Then, by molding with the molding die while continuously flowing a fluid such as gas or liquid in the flow path of the special molding core, a casting product, a plastic molding product, a ceramic molding product, etc. can be obtained. The molded product is molded.

Therefore, the non-sand core used in the present invention is
When molding a molded product while continuously flowing a fluid such as gas or liquid inside, it has pressure resistance (non-disintegration) and, after molding, heat that is completely removed by the residual heat of the molded product. It is required to have disappearance (complete removability).

Further, the non-sand core is required to have a condition that does not adversely affect the molded product such as generation of a large amount of gas during the molding.

In the present embodiment, among the molding cores used for molding various molded products such as the above-mentioned cast products, plastic molded products and ceramic molded products, the casting used for casting the cast products. The molding core will be described with reference to the molding core.

Here, in the case of obtaining a cast product by the casting, and as one of them, a special molding core as a die casting casting core used when obtaining a cast product by die casting is The case of using a synthetic resin core as the sand core will be described.

A core (synthetic resin core or plastic core) made of a synthetic resin (plastic) as a non-sand core which is the special molding core (hereinafter referred to as "resin core").
1 is made of synthetic resin (plastic).

The resin core 1 is made of a synthetic resin (plastic) by a synthetic resin molding method (plastic molding method) such as injection molding, as shown in FIG. Is formed into a hollow shape having a flow path S having an inlet S1 and an outlet S2 for continuously flowing a fluid such as the above.

Further, as best shown in FIG. 1, the resin core 1 is introduced into the inflow hole 7 and the outflow hole 8 provided in the lower mold 3 of the casting mold 4 and the inflow port S1 and the inflow hole S1. The resin core 1 is disposed between the upper mold 2 and the lower mold 3 so as to match the outlet S2, and the mold 4 having the cavity 5 is formed.

Thus, as shown in FIG. 1, the resin core 1 is disposed between the upper mold 2 and the lower mold 3 so that the inside of the mold 4 is molded. The cavity 5 having a shape corresponding to the shape of the cast product 6 can be formed.

Next, the case of performing die casting, which is one of the casting methods using the non-sand core as the special molding core of the present invention, will be described.

First, although not shown, the resin core 1 is molded from a synthetic resin (plastic) by a synthetic resin molding method (plastic molding method) such as injection molding.

Then, as shown in FIG. 1, the inflow port S1 and the outflow port S2 are aligned with the inflow hole 7 and the outflow hole 8 provided in the lower mold 3 of the mold 4. hand,
The resin core 1 is disposed between the upper mold 2 and the lower mold 3 to form a mold 4 having a cavity 5 having a shape corresponding to the shape of the cast product 6 to be molded.

Next, as shown in FIGS. 1 and 2, a fluid such as a gas or a liquid (in this embodiment, compressed air compressed by a compressor) is introduced into the inflow hole 7 and the inflow port. The resin core 1 is forcibly cooled by flowing the fluid from S1 through the flow path S and outflowing from the outflow hole 8 and the outflow port S2 so that the resin core 1 is forcibly cooled. It is possible to maintain the pressure resistance when pouring the molten metal, prevent deformation, and maintain the original shape.

Subsequently, as well shown in FIGS. 1 and 2, while the fluid (compressed air in this embodiment) such as gas or liquid is continuously flowed through the flow path S, the mold 4 is used. By pouring the molten metal such as an aluminum molten metal into the hollow portion 5 formed inside while applying pressure according to the material of the cast product,
A cast product 6 having a shape corresponding to the shape of the cavity 5 is cast and formed.

Further, as best shown in FIG.
Since the casting is completed by removing the cast product 6 formed as described above from the mold 4, unnecessary parts such as burrs of the cast product 6 are removed, and the cast product 6 which is a desired final product. Is formed.

The cast product 6 thus formed has excellent appearance quality and functional quality since defects such as a blowhole are prevented from occurring.

Therefore, compared with the case where a casting product is obtained by casting using a sand core which is generally widely used as a conventional core, the man-hours are greatly reduced, and a casting product of excellent quality is efficiently produced. You will get better.

As a result, the resin core 1 contributes to the formation of the intended casting 6 by maintaining its shape during casting, and the residual heat of the casting 6 is applied after casting. Since it is dissolved and removed, no residue remains.

That is, since the resin core 1 is forcibly cooled and heat-exchanged by continuously flowing a fluid such as gas or liquid in the flow path S, the heat resistance to the molten metal is remarkably improved, and Since the pressure resistance is remarkably improved, the initial shape can be maintained without thermal deformation or pressure deformation even when pouring the high-pressure molten metal during molding.

Further, the temperature of the molten metal is considerably lower than the initial temperature (for example, in the case of aluminum molten metal, about 660 ° C.) by the time it reaches the cavity 5 of the mold 4, so that Even if the molten metal acts due to its own temperature and latent heat, the resin core 1 can maintain the initial shape without being immediately melted due to the reflecting action and the temperature action.

The resin core 1 is melted and removed by the residual heat of the casting 6 after the molten metal has cooled and solidified for a predetermined time after pouring the molten metal into the hollow portion 5. Of.

Therefore, by casting the resin core 1 in its original shape without deformation, a cast product 6 having a shape corresponding to the shape of the cavity 5 can be obtained.

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

Therefore, by casting using a sand core which is generally widely used as a conventional core, the man-hours are greatly reduced as compared with the case of obtaining a cast product, and a cast product of excellent quality is obtained. You will be able to obtain it efficiently.

As described above, when die casting is performed using the die casting core which is the first embodiment of the molding special core of the present invention, the resin core 1 has a shape which is obtained during casting. By holding the above, while contributing to the formation of the desired casting product 6, after casting, since it is melted by the residual heat of the casting product 6 and completely removed and disappeared, there is no residual residue, It is easy to completely remove the core afterwards, and it is possible to prevent defects such as wear and breakage of the product, improve yield, save time and cost, and improve productivity. it can.

The resin core of this embodiment has pressure resistance when molding a molded product while continuously flowing a fluid such as gas or liquid inside, and after molding,
It is required to have heat extinction (complete removability) that completely removes and disappears due to residual heat of the molded product, and does not adversely affect the cast product such as generating a large amount of gas during casting, Synthetic resins (plastics) as core materials satisfying this condition include the following.

That is, as a synthetic resin (plastic) as a core material having all of the above conditions, for example,
There is a thermoplastic synthetic resin, which satisfies all of the above conditions, and a cast product that sufficiently satisfies the initial purpose can be obtained.

The most suitable of these thermoplastic synthetic resins are fluororesins (polyfluoroethylene resins) such as tetrafluoroethylene resin, polyimide resins, polyamideimide resins and polysulfone resins, and any of the above conditions is used. Also, it is possible to obtain a cast product that satisfies the initial purpose.

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

Other examples include polyethylene resin, polyester resin (tetoron resin) and polysulfone sun resin, which meet all of the above conditions and obtain a cast product satisfying the initial purpose. be able to.

Further, as the core made of synthetic resin (plastic) used for the special core for casting of this embodiment,
Not limited to the above synthetic resin (plastic), it has pressure resistance at the time of molding when molding a molded product while continuously flowing a fluid such as gas or liquid inside, and after molding, residual heat of the molded product If it does not have a bad effect on the cast product such as generation of a large amount of gas at the time of casting as well as heat extinction property (complete removal property) that is completely removed by the synthetic resin other than the above examples ( Needless to say, plastic) can also be used, and the same effects as those of the above-mentioned embodiment can be obtained.

Next, FIG. 5 shows a second embodiment of the molding special core of the present invention, and the molding special core made of rubber (hereinafter referred to as "rubber core") will be described.

That is, the rubber core 1 which is the molding special core is made of natural rubber, synthetic rubber, silicon rubber, fluorine rubber or the like, and is made of gas or liquid as well shown in FIG. Inlet S1 and outlet S for continuously flowing fluid such as
2 is molded into a hollow shape having a flow path S formed therein.

Further, as best shown in FIG. 1, the rubber core 1 is provided with an inflow hole 7 and an outflow hole 8 provided in the lower mold 3 of the casting mold 4 and the inflow port S1 and the inflow hole S1. The rubber core 1 can be arranged between the upper mold 2 and the lower mold 3 so that the outlet S2 is aligned with the outlet S2 to form the mold 4 having the cavity 5.

As shown in FIG. 1, the rubber core 1 is arranged between the upper mold 2 and the lower mold 3,
After the mold 4 having the cavity 5 is formed, as shown in FIGS. 1 and 2, in the flow path S formed in the rubber core 1, a fluid such as gas or liquid (this embodiment is used). In the example,
While continuously flowing compressed air (compressed by a compressor), a molten metal such as an aluminum molten metal is poured into the cavity 5 formed in the mold 4 in accordance with the material of the cast product, whereby the rubber core 1 The cast product 6 having a shape corresponding to the shape of the cavity 5 while maintaining the original shape without deforming the
Is cast.

Subsequently, as well shown in FIGS. 2 and 3, the casting 6 formed as described above is taken out from the mold 4, whereby the casting is completed and burrs and the like of the casting 6 are removed. The unnecessary portion is removed to form a casting 6 as a desired finished product.

The cast product 6 formed in this manner is a cast product in which the occurrence of defects such as cavities is prevented and the appearance quality and functional quality are excellent.

Therefore, by casting using a sand core which is generally widely used as a conventional core, the man-hours are greatly reduced as compared with the case of obtaining a cast product, and a cast product of excellent quality is obtained. You will be able to obtain it efficiently.

In this case, since the temperature of the molten metal is considerably lower than the initial temperature by the time it reaches the cavity 5 of the mold 4, the temperature of the rubber core 1 is lowered by the forced cooling by the fluid. Combined with the decrease and the improvement of pressure resistance, even if the molten metal acts due to its own temperature and latent heat, the initial shape is maintained without immediate melting due to the reflecting action and the temperature action. be able to.

Further, FIG. 6 shows a third embodiment of a molding core according to the present invention, and a molding core made of a fibrous material such as paper (hereinafter referred to as "paper core") will be described. .

That is, the paper core 1 which is the molding special core is made of a fibrous material such as paper, synthetic paper, non-woven fabric, fiber, etc., and gas, liquid, etc. as well shown in FIG. Is formed into a hollow shape having a flow path S having an inlet S1 and an outlet S2 for continuously flowing the fluid.

Further, as best shown in FIG. 1, the paper core 1 has an inflow hole 7 provided in the lower mold 3 of the mold 4.
The inflow port S1 and the outflow port S2 are aligned with the outflow hole 8 and the outflow hole 8, the paper core 1 is disposed between the upper mold 2 and the lower mold 3, and the mold 4 having the cavity 5 is provided. Can be formed.

After the paper core 1 is disposed between the upper mold 2 and the lower mold 3 to form a mold 4 having a cavity 5 as shown in FIG. As shown in FIGS. 1 and 2, in the flow path S formed in the paper core 1, a fluid such as gas or liquid (compressed by a compressor in the present embodiment is compressed). While continuously flowing air), by pouring a molten metal such as an aluminum molten metal into the hollow portion 5 formed in the mold 4 depending on the material of the cast product,
A cast product 6 having a shape corresponding to the shape of the hollow portion 5 is cast in a state where the original shape is maintained without deforming the paper core 1.

Subsequently, as well shown in FIGS. 2 and 3, the casting 6 formed as described above is taken out from the mold 4, whereby the casting is completed and burrs and the like of the casting 6 are removed. The unnecessary portion is removed to form a casting 6 as a desired finished product.

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

Therefore, by casting using a sand core which is generally widely used as a conventional core, the man-hours are greatly reduced as compared with the case of obtaining a cast product, and a cast product of excellent quality is obtained. You will be able to obtain it efficiently.

In this case, since the temperature of the molten metal is considerably lower than the initial temperature by the time it reaches the cavity 5 of the mold 4, the temperature of the paper core 1 is lowered by the forced cooling by the fluid. Combined with the decrease and the improvement of pressure resistance, even if the molten metal acts due to its own temperature and latent heat, the initial shape is maintained without immediate melting due to the reflecting action and the temperature action. be able to.

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

That is, as the material of the molding special core of the present invention, the resin core shown in the above embodiment, the rubber core such as natural rubber or synthetic rubber, and the paper core made of fibrous material such as paper. However, by producing a molded product while continuously flowing a fluid such as gas or liquid inside the core, it is possible to combine the conflicting conditions of pressure resistance during molding and heat dissipation after molding. As long as it is a child, it can be a low melting metal such as tin, lead, antimony, ceramics, or other single material, and also FRR (fiber reinforced rubber), FRP (fiber reinforced plastic), CFRP (carbon fiber reinforced). Plastic), GFRP (glass fiber reinforced plastic) and other composite materials can be used, and special molding cores using various materials are conceivable, and the same effects as those of the above-described embodiments can be obtained.

That is, the special molding core used in the present invention is not limited to the materials and shapes of the above-mentioned embodiments, but can be applied to various shapes using various materials, and cast products It is possible to improve the quality of the resin core, the rubber core, and the paper core shown in the above-mentioned embodiment, while continuously flowing a fluid such as gas or liquid inside the core. By manufacturing a molded product, it is sufficient as long as it is a core having a reciprocal condition of pressure resistance at the time of molding and heat dissipation after molding, and many modifications are conceivable. Obtainable.

Further, the special molding core of the present invention is not limited to die casting as one of the casting methods shown in the above-mentioned embodiment, but a specific step is added to the die casting method to obtain a cast product. The quality can be improved and the like is not limited to the above-described embodiment, and many modifications can be considered.

Further, in the above embodiment, the case of performing die casting as one of the casting methods has been described.
The molding special core of the present invention is not limited to the die casting, and is a cast product cast by a sand type gravity casting method, a die gravity casting method, a low pressure casting method, a precision casting method, or another casting method. Of course, the same excellent effects as those of the above-mentioned embodiment can be obtained.

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

That is, in the gravity casting method, the residence time of the molten metal during casting is longer than that of other casting methods, the time during which the molten metal contacts the core is long, and the temperature of the molten metal is relatively high. In particular, the core is required to have pressure resistance and heat resistance, but by using the molding special core 1 described above, a molded product can be obtained by continuously flowing a fluid such as gas or liquid inside the core. By molding, since the core is forcibly cooled to exchange heat, the heat resistance to the molten metal can be significantly improved and the pressure resistance can be significantly improved.
Even when the molten metal having a long residence time at the time of casting is poured, it is possible to maintain the initial shape without thermal deformation and contribute to the formation of the intended cast product 6.

At this time, referring to FIGS. 1 to 4, the special molding core will be described with respect to the special molding core used in the gravity casting method which is the fourth embodiment of the special molding core of the present invention.

That is, in this embodiment, when a casting product is obtained by a gravity casting method using a casting special core as a molding special core, one of them is the casting special core. The case of using a synthetic resin core will be described.

First, although illustration is omitted, synthetic resin is used in the same manner as described above, as shown in FIG.
As shown in FIG. 1, after molding the resin core 1 in which a flow path S having an inlet S1 and an outlet S2 for continuously flowing a fluid such as gas or liquid is formed. In addition, the inlet S and the outlet 8 provided in the lower mold 3 are connected to the inlet S
1 and the outlet S2 are aligned, and the resin core 1 is moved to the upper mold 2
And a lower mold 3 to form a mold 4 having a cavity 5.

Next, as shown in FIGS. 1 and 2, a fluid such as a gas or a liquid (in the present embodiment, compressed air compressed by a compressor) is fed into the inlet 7 and the inlet. The resin core 1 is forcibly cooled by flowing the fluid from S1 and then outflowing from the outflow hole 8 and the outflow port S2 through the flow path S to continuously flow through the flow path S, and at the same time, the molten metal is melted. It is possible to maintain the pressure resistance when pouring the molten metal, prevent deformation, and maintain the original shape.

Subsequently, as well shown in FIGS. 1 and 2, while continuously flowing a fluid such as gas or liquid (compressed air in this embodiment) through the flow path S, the mold 4 A molten metal such as an aluminum molten metal is poured into the hollow portion 5 formed inside depending on the material of the cast product.

As a result, the resin core 1 has the flow path S
Since heat exchange is performed by forced cooling by continuously flowing a fluid such as gas or liquid to the molten metal, the heat resistance to the molten metal is significantly improved and the pressure resistance is also significantly improved. Even when the molten metal is poured, the initial shape can be maintained without thermal deformation or pressure deformation.

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

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

In this way, the resin core 1 contributes to the formation of the intended casting 6 by maintaining its shape during casting, and after casting, the resin core 1 It is dissolved by residual heat and completely removed and disappeared, so no residue remains.

Subsequently, as well shown in FIG. 2 and FIG. 3, the casting product 6 formed as described above is taken out from the mold 4, whereby the casting is completed, and the initial intended casting product is obtained. Obtainable.

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

Therefore, by casting using a sand core which is generally widely used as a conventional core, the man-hours are greatly reduced as compared with the case where a cast product is obtained, and a cast product of excellent quality is obtained. You will be able to obtain it efficiently.

As described above, also in the gravity casting method, the molding special core 1 contributes to the formation of the desired casting 6 by holding its shape during casting, and after casting, Since the cast product 6 is melted and removed by residual heat, no residue remains, and the core after casting is easily removed completely, and defects such as wear and damage of the product can be prevented. In addition, the yield can be improved, time and cost can be saved, and productivity can be improved.

The fluid used in the present invention is not limited to the compressed air of the above embodiment, but may be a gas or liquid other than the compressed air or a mixed fluid of gas and liquid, and the flow rate is adjusted. By adjusting the fluid temperature
The pressure resistance and heat resistance of the core can be adjusted.

Even when the special casting core is used as the molding special core as one of the embodiments of the present invention, the die casting casting method and the gravity casting method of the above-described embodiments However, the present invention is not limited to the above, and can be applied to a low pressure casting method, a precision casting method, and other casting methods. Many modifications are conceivable, and the same effects as those of the above-described embodiment can be obtained.

Next, the operation of the special molding core according to this embodiment will be described.

That is, according to the present invention, by using a special molding core as the core, the productivity is improved and the range of application is enhanced, and a molded product of excellent quality is efficiently obtained. For example, in the case of a molding special core for casting, which is used to form a molded product such as a cast product, a plastic molded product, a ceramic molded product, etc. , Has the following effects. (1) Since the molded product is manufactured while continuously flowing a fluid such as gas or liquid inside the core, the core is pressure-resistant with the fluid such as gas or liquid continuously flowing 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 relaxed, and the selection range of the core material can be expanded. (2) The pressure resistance and heat resistance of the core can be adjusted by adjusting the flow rate and the fluid temperature of a fluid such as gas or liquid that is continuously flown into the core. (3) By using a special molding core as the core, molding of the core is facilitated, molding equipment is simplified, the number of steps is reduced, and time and cost can be reduced. (4) Since a special molding core is used as the core, it does not break even if dropped or thrown, so handling is easy, and man-hours are reduced, such as easier transportation and storage, and time and cost are reduced. be able to. (5) Since the molding special core to be used does not contain a permeation component such as a binder, the core component is prevented from permeating into the molded product, so that the occurrence of defects such as porosity is prevented. In addition, it is possible to prevent defective products from being formed and to improve yield and productivity. (6) By using a special molding core as the core, it becomes easy to form a hollow portion or an undercut portion,
Moreover, since the strength of the core is improved, it is possible to mold all shapes and sizes without being restricted by the shape and size, and it is possible to expand the range of application. (7) By using a core that has the conflicting conditions of pressure resistance during molding and heat dissipation after molding, problems such as molten metal insertion during molding can be avoided and pressure resistance (non-disintegration) The heat dissipation of the core after molding and the easy removal of core components are prevented, and the adhesion to the molded product is prevented, and the occurrence of molded product defects such as wear and damage of the molded product is prevented. Can be achieved. (8) The special molding core does not contain components that are difficult to remove, such as a binder, and has heat dissipation properties after molding, so it is easy to completely remove the core and prevent pollution. In addition to the above, the number of steps can be reduced, and the time and cost can be reduced.

Incidentally, the special molding core of the present invention is not limited to the above-mentioned respective embodiments, and many modifications can be considered.

That is, the special core for molding of the present invention is not limited to the case of obtaining a cast product by the casting shown in each of the above-mentioned examples, and can be applied to a molded product formed by a molding method other than the casting. You can

For example, the special molding core of the present invention is used in various molding methods such as plastic molding and ceramic molding, which are molding methods other than the above-mentioned casting, to obtain a plastic molded article or ceramic molding of excellent quality. Various molded products such as molded products can be efficiently obtained, and at the same time, productivity can be improved and the range of application can be increased, and the cost of molded products can be significantly reduced.

The present invention uses a molding special core as a core, forms a molding die such as a plastic molding die or a ceramic molding die, and forms a hollow portion inside the molding special core. In addition, various moldings such as plastic moldings and ceramic moldings can be molded by using the molding die while continuously flowing a fluid such as gas or liquid.

During molding, the special molding core contributes to the formation of a desired molded product by maintaining its shape, and is melted by residual heat of the molded product after molding. Since it is removed and disappears, there is no residue,
It is easy to completely remove the core of a molded product, prevent defects such as wear and damage of the product, improve yield, save time and cost, and improve productivity. You will be able to

Further, the special molding core of the present invention is not limited to the case obtained by each of the above-mentioned molding methods,
It is possible to further improve the quality of the molded product by adding a specific step, and the present invention is not limited to the case obtained by the above-mentioned molding method, and many modified examples are possible.

Even when the special molding core of the present invention is used in various molding methods such as plastic molding and ceramic molding, which are molding methods other than the above-mentioned casting, the materials and shapes of the above-mentioned examples are used. The present invention is not limited to those described above, but can be applied to various shapes using composite materials and other materials other than those in the above-mentioned respective examples, and the quality of molded products can be improved.

That is, as the material of the molding special core of the present invention, the resin core shown in the above embodiment, the rubber core of natural rubber or synthetic rubber, the paper core made of fibrous material such as paper, etc. However, by producing a molded product while continuously flowing a fluid such as gas or liquid inside the core, it is possible to combine the conflicting conditions of pressure resistance during molding and heat dissipation after molding. As long as it is a child, it can be a low melting metal such as tin, lead, antimony, ceramics, or other single material, and also FRR (fiber reinforced rubber), FRP (fiber reinforced plastic), CFRP (carbon fiber reinforced). Plastic), GFRP (glass fiber reinforced plastic) and other composite materials can be used, and special molding cores using various materials are conceivable, and the same effects as those of the above-described embodiments can be obtained.

The special molding core of the present invention is applied to various molding methods such as injection molding adopted as part of plastic molding and injection molding adopted as part of ceramic molding. Even in such a case, as in the case of the casting special core used for the casting, it has an excellent action, and the conventional problems can be solved.

That is, according to the molding special core of the present invention, by molding while continuously flowing a fluid such as a gas or a liquid inside, the shape is maintained at the time of molding, so that the desired shape can be obtained. In addition to contributing to the formation of the target molded product, after molding, it is melted and removed by the residual heat of the molded product, so there is no residue and the core of the molded product can be completely removed easily. The range of can be significantly expanded,
In addition to facilitating core molding and reducing costs,
It is possible to prevent defects such as wear and breakage of products, improve yield, save time and cost, and improve productivity.

[0104]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, by using the non-sand core as the molding special core as the core, the productivity is improved and the applicable range is expanded, and the molding having excellent quality is achieved. The idea is to obtain a cast product, for example, to obtain a cast product among the special molding cores used for forming a cast product, a plastic molded product, a ceramic molded product, or the like. In the case of a special molding core, there are the following excellent effects. (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) The use of a special molding core as the core facilitates molding of the core, simplifies molding equipment, reduces the number of steps, and has the advantage of reducing time and cost. is there. (4) Since a special molding core is used as the core, it does not break even if dropped or thrown, so handling is easy, and man-hours are reduced, such as easier transportation and storage, and time and cost are reduced. There is an advantage that can be. (5) Since the molding special core used does not contain a permeation component such as a binder, the core component is prevented from permeating into the molded product, so that the occurrence of defects such as porosity is prevented. In addition, there is an advantage that defective products of molded products can be prevented, yield can be improved, and productivity can be improved. (6) By using a special molding core as the core, it becomes easy to form a hollow portion or an undercut portion,
Moreover, since the strength of the core is improved, there is an advantage that it is possible to mold all shapes and sizes without being restricted by the shape and size, and to expand the applicable range. (7) By using a core that has the conflicting conditions of pressure resistance during molding and heat dissipation after molding, problems such as molten metal insertion during molding can be avoided and pressure resistance (non-disintegration) The heat dissipation of the core after molding and the easy removal of core components are prevented, and the adhesion to the molded product is prevented, and the occurrence of molded product defects such as wear and damage of the molded product is prevented. There is an advantage that can be achieved. (8) The special molding core does not contain components that are difficult to remove, such as a binder, and has heat dissipation properties after molding, so it is easy to completely remove the core and prevent pollution. In addition to the advantages, the man-hours can be reduced, and the time and cost can be reduced.

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

The productivity can be improved and the range of application can be increased. By using the special molding core, molding of the core is facilitated, molding equipment is simplified, and the number of steps is reduced. The time and cost can be reduced, handling is easy, transportation and storage are easy, and pressure adjustment at the time of molding is not required.
There are various excellent advantages such as reduction of time and cost.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a method of forming a mold by using a resin core of a molding special core according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a method for forming a cast product by pouring a molten metal out of a special molding core according to one embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a cast product taken out from the mold of the special molding core of one embodiment according to the present invention.

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

FIG. 5 is a cross-sectional view showing a second embodiment of the special molding core.

FIG. 6 is a sectional view showing a third embodiment of the special molding core.

[Explanation of symbols]

1 Special molding core (non-sand core) (resin core) (rubber core) (paper core) 2 Upper mold 3 Lower mold 4 Mold (plastic mold) (ceramic mold) 5 Cavity 6 Molded product (cast product) (Plastic molded product) (Ceramic molded product) 7 Inflow hole 8 Outflow hole S Flow path S1 Inlet S2 Outlet

Claims (5)

[Claims] 1. A molding core used for forming a hollow shape, an undercut shape, or the like into a molded product such as a cast product, a plastic molded product, or a ceramic molded product. A special molding core, which is formed from a sand core and is provided with a flow path for molding while continuously flowing a fluid such as gas or liquid inside the molding core. . 2. A special core for molding according to claim 1, wherein a core having a reciprocal condition of pressure resistance during molding and heat dissipation after molding is used as the non-sand core. Child. 3. The special molding core according to claim 1 or 2, wherein a core made of synthetic resin (plastic) is used as the non-sand core. 4. The molding special core according to claim 1 or 2, wherein a core made of rubber is used as the non-sand core. 5. The special molding core according to claim 1 or 2, wherein a core made of a fibrous material such as paper is used as the non-sand core.