JP2976161B2 - Molding method using special core - Google Patents

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 core, and more particularly to a method of forming a special core by using a special core without using a conventionally used sand core. The present invention relates to a molding method such as casting, plastic molding, ceramic molding and the like using a special core capable of efficiently forming a molded product having a wide range of shapes without being restricted by the above-mentioned restrictions.

[0002]

2. Description of the Related Art Molding methods such as casting employed as part of machine work, injection molding employed as part of plastic molding, and injection molding employed as part of ceramic molding are not disclosed. Conventionally, a non-collapsible core or a collapsible core has been used to form a hollow portion or an undercut portion.

[0003] For example, in the above casting, as the former (non-collapseable core), there is a metal core, but it cannot be used for anything other than those that can be directly cut or deformed. Was restricted to things.

As the latter (collapseable core), a sand core is generally used, but it is difficult to mold,
Not only is it easy to disintegrate and handling is difficult, but also it is difficult to satisfy the reciprocal conditions of pressure resistance during molding and disintegration after molding.

In recent years, it has been proposed to apply a special coating to the surface of the sand core in the above casting, but it has not been possible to solve the problem because of the following problems. Was. (1) Coating is difficult, for example, it is necessary to form not only one layer but also a plurality of layers. Therefore, the coating is time-consuming and time-consuming, not only takes time and expense, but also takes time and cost. The initial purpose is also difficult to achieve. (2) Since it is difficult to completely remove the binder as a component of the coating layer and the sand core after molding, sand baking treatment for removing the coating layer and the binder is required. It takes time and money. (3) Since sand cores are difficult to mold, not only equipment and man-hours are required, but the molded sand cores are also fragile, difficult to handle, require man-hours, and have a low yield.
It takes time and money. (4) Since the sand core requires complicated pressure adjustment to prevent collapse during casting, and complete collapse after casting is difficult, a heat treatment process, a sand removal process, and a sand removal inspection are required. It takes man-hours and takes time and money. (5) Defective products are liable to occur, such as intrusion of molten metal between core sand particles during casting, and formation of cavities in the cast product due to penetration of components of the sand core into the cast product. The yield of casting is poor, and the productivity is poor. (6) It is difficult to completely remove the core sand after casting, and it adheres to a cast product, and causes problems such as wear and breakage of the product. (7) Since castings of complicated shapes and large castings are difficult or virtually impossible to cast, the applicable range is limited,
There is a problem in design and production. (8) When the sand of the sand core is reused after casting, since the coating layer and the binder are contained, it is difficult to completely remove the coating layer and the binder. And
It takes time and money. (9) Sand cores have many drawbacks such as molding difficulty, easy collapse, and handling difficulties, and it is difficult to satisfy the conflicting conditions of pressure resistance during casting and disintegration after casting. The following steps are required, the yield is low, and time and cost are required.

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

Further, in molding methods such as injection molding employed as part of plastic molding and injection molding etc. employed as part of ceramic molding,
There were various problems similarly to the above casting.

For example, the core must be formed from a specific material having pressure resistance and heat resistance at the time of molding, and it is difficult to mold the core and the cost is high. 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 the casting method of the above-mentioned molding methods, (1) the use of a special core relaxes the conditions such as pressure resistance and heat resistance required for the core, and the selection range of the core material. To enlarge. (2) The pressure resistance and heat resistance of the core are adjusted by adjusting the flow rate and fluid temperature of a fluid such as a gas or a liquid that flows continuously inside the core. (3) By using a hard-to-break special core as a core,
Easier molding and handling of the core, reducing man-hours and time and costs. (4) By using a special core that does not use a penetrating component such as a binder, the core component is prevented from penetrating into a casting, and the occurrence of defects such as the occurrence of a cavity is prevented. In addition, it prevents the occurrence of defective cast products, thereby contributing to improved yield and improved productivity. (5) By using a core that has the reciprocal conditions of the pressure resistance at the time of molding and the heat dissipation property after molding, it is possible to avoid problems such as insertion of molten metal during molding and pressure resistance (non-disintegration). And facilitates the heat dissipation of the core after molding and the complete removal of the core component, prevents adhesion to the molded product, and reduces the occurrence of molded product defects such as wear and breakage of the molded product. Block. (6) The use of a special core facilitates the formation of a hollow portion or an undercut portion.
Enables casting of all shapes and sizes without being restricted by shape and size, and expands the applicable range. (7) The special core does not contain any hard-to-remove components such as binders, making it easy to completely remove the core after casting, facilitating reuse, preventing pollution, and reducing man-hours. Reduce, save time and money.

[0010] Further, in a molding method such as injection molding adopted as a part of plastic molding and a molding method such as injection molding adopted as a part of ceramic molding,
Various problems can be solved similarly to the casting.

For example, the core can be formed by molding a molded product while continuously flowing a fluid such as a gas or a liquid therein, so that the range of material selection can be greatly expanded. The various problems described above can be solved by facilitating molding and reducing costs.

[0012]

SUMMARY OF THE INVENTION According to the present invention, a mold is formed by using a non-sand core as a core, and a fluid such as gas or liquid is formed inside the core. Is achieved by providing a molding method using a special core, characterized in that a molded article is molded using the molding die while continuously flowing.

[0013]

According to the present invention, the following effects are obtained.

That is, according to the present invention, a molding die is formed by using a non-sand core as a core, and the molding die is formed while a fluid such as a gas or a liquid is continuously flowed inside the core. By using a molding method using a special core characterized by molding a molded product using, the idea is to improve the productivity and expand the applicable range, for example, among the molding method, In casting, (1) Since a molded article is formed while continuously flowing a fluid such as gas or liquid into the core, the core continuously flows a fluid such as gas or liquid into the core. In such a state, conditions such as pressure resistance and heat resistance may be satisfied, so that conditions such as pressure resistance and 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 fluid temperature of a fluid such as a gas or a liquid that flows continuously inside the core. (3) By using a special core as the core, the molding of the core is facilitated, the molding equipment is simplified, the number of steps is reduced, and the time and cost can be reduced. (4) Since a special core is used as the core, it is easy to handle because it does not break when dropped or thrown, making it easier to transport and store, reducing man-hours, and reducing time and costs. it can. (5) Since the special core used does not contain a penetrating component such as a binder, the core component is prevented from penetrating into the molded product, thereby preventing the occurrence of troubles such as the occurrence of voids and forming. The occurrence of defective products is prevented, and the yield and the productivity can be improved. (6) By using a special core as the core, it is easy to form a hollow portion or an undercut portion, and the core strength is improved. In this way, it is possible to expand the applicable range. (7) By using a core that has the reciprocal conditions of the pressure resistance during molding and the heat dissipation property after molding, it is possible to avoid problems such as insertion of a molten metal during molding and to achieve pressure resistance (non-disintegration). And facilitates the heat dissipation of the core after molding and the complete removal of the core component, preventing adhesion to the molded product and preventing the occurrence of molded product defects such as abrasion and breakage of the molded product. Can be achieved. (8) The special core does not contain components that are difficult to remove, such as a binder, and has heat dissipation properties after molding.
The complete removal of the core is facilitated, and the occurrence of pollution can be prevented. In addition, the number of steps can be reduced, and the time and cost can be reduced.

Further, in a molding method such as injection molding employed as a part of plastic molding and a molding method such as injection molding employed as a part of ceramic molding,
By adopting the above configuration, productivity can be improved and the applicable range can be expanded. As in the case of the above-described casting, by using a special core, the molding of the core becomes easy, and the molding equipment is simplified. In addition, the number of processes is reduced, the time and cost can be reduced, handling becomes easier, transport and storage become easier, and man-hours such as pressure adjustment during molding become unnecessary. In addition, there are various functions such as reduction in cost.

[0016]

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail with reference to the accompanying drawings, in which: FIG.

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

That is, the present invention uses a non-sand core as a core to form a mold such as a mold, a plastic molding die, or a ceramic molding die, and allows a fluid such as a gas or a liquid to flow inside the core. This is a molding method using a special core, characterized in that a molded product such as a cast product, a plastic molded product, or a ceramic molded product is molded using the molding die while continuously flowing.

The non-sand core used in the present invention comprises:
When molding a molded product while continuously flowing a fluid such as a gas or a liquid therein, the molded product has pressure resistance, and after the molding, has a heat dissipation property (complete removal) in which the molded product is completely removed and lost by residual heat. ) Is required.

The non-sand core is required to satisfy conditions that do not adversely affect the molded product, such as generating a large amount of gas during the molding.

In the present embodiment, there is provided a molding method using a special core, which comprises molding a molded product such as a cast product, a plastic molded product, or a ceramic molded product using the non-sand core. A casting method using a special core for forming a casting will be described.

Here, a description will be given of a case where die casting is performed as one of the cases where the casting is performed, and a case where a synthetic resin core is used as the non-sand core.

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

First Step First, although not shown in the drawings, a synthetic resin (plastic) is used by a synthetic resin molding method (plastic molding method) such as injection molding, as shown in FIG. Core (plastic core) (hereinafter referred to as a plastic core) made of a synthetic resin formed in a hollow shape having a flow passage S provided therein with an inlet S1 and an outlet S2 for continuously flowing a fluid such as fluid or a liquid. (Referred to as “resin core”) 1 is formed.

Second Step Subsequently, as shown in FIG. 1, the inflow port S1 is inserted into the inflow hole 7 and the outflow hole 8 provided in the lower die 3.
The resin core 1 is disposed between the upper mold 2 and the lower mold 3 by matching the outlet S2 and the mold 4 having the cavity 5.

Third Step 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. The fluid flows continuously through the flow path S by flowing through the flow path S through the flow path S and flowing out from the outflow hole 8 and the flow outlet S2.

Thus, the resin core 1 is forcibly cooled, the pressure resistance when the molten metal is poured is maintained, deformation is prevented, and the original shape is maintained.

Fourth Step Next, as shown in FIGS. 1 and 2, while continuously flowing a fluid such as gas or liquid (in this embodiment, compressed air) through the flow path S, Cavity 5 formed in mold 4
The molten metal such as aluminum is poured while applying pressure depending on the material of the casting.

Thus, the resin core 1 is connected to the flow path S
Forcibly cools and heat exchanges by continuously flowing a fluid such as gas or liquid into the furnace, which significantly improves the heat resistance and the pressure resistance of the molten metal. Even with hot water, without thermal deformation or pressure deformation,
The initial shape can be maintained.

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

For this reason, a casting 6 having a shape corresponding to the shape of the cavity 5 is cast while maintaining the original shape without deforming the resin core 1.

The resin core 1 retains its shape at the time of casting, thereby contributing to the formation of the desired cast product 6 and, after casting, is melted by the residual heat of the cast product 6. As it is completely removed and eliminated, no residue remains.

Subsequently, as shown in FIG. 2 and FIG. 3, the casting 6 is removed from the mold 4 to complete the casting.

Fourth Step Further, although not shown, a finished product can be obtained by removing unnecessary portions such as burrs of the cast product 6.

Therefore, compared to the conventional casting method requiring the following ten steps, only four steps are required, and six steps are omitted.

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

As described above, when performing die casting as one of the casting methods using a resin core, which is the first embodiment of the molding method using the special core of the present invention, the resin core is used. 1 contributes to the formation of an intended cast product 6 by maintaining its shape during casting,
After casting, the casting 6 is melted and completely removed and lost by the residual heat, so that no residue remains and the core is easily removed completely after casting, preventing problems such as wear and breakage of the product. In addition, the yield can be improved, time and cost can be saved, and productivity can be improved.

The resin core of the present embodiment has pressure resistance when molding a molded product while continuously flowing a fluid such as a gas or a liquid therein, and after molding,
It is required to have a heat dissipation property (complete removal property) that is completely removed and lost by the residual heat of the molded article, and that it does not give an adverse effect on the cast article such as generating a large amount of gas during casting. The following are examples of the synthetic resin (plastic) as the core material satisfying this condition.

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

The most suitable thermoplastic synthetic resin is a fluororesin (polyfluoroethylene resin) such as an ethylene tetrafluoride resin, a polyimide resin, a polyamideimide resin, or a polysulfone resin. And a cast product satisfying the initial purpose can be obtained.

Further, next to this, there are polyamide resin (nylon resin) and polypropylene resin, which satisfy both of the above conditions, and can provide a cast product satisfying the initial purpose.

Other examples include a polyethylene resin, a polyester resin (tetron resin) and a polysulfone sun resin, and a cast product satisfying both of the above conditions and satisfying the initial purpose is obtained. be able to.

The core made of a synthetic resin (plastic) used for the special core for casting of the present embodiment is not limited to the above-mentioned synthetic resin (plastic), and a fluid such as a gas or a liquid is contained therein. It has pressure resistance at the time of molding to form a molded product while flowing continuously, and also has a heat dissipation property (complete removal property) that completely removes and disappears due to residual heat of the molded product after molding. As long as it does not adversely affect the cast product, such as generating a large amount of gas, it goes without saying that a synthetic resin (plastic) other than the above embodiment can be used, and the same effects as those of the above embodiment can be obtained. Can be.

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

That is, the special rubber core 1
Is a flow path provided with an inlet S1 and an outlet S2 for continuously flowing a fluid such as a gas or a liquid as shown in FIG. 5 using a rubber such as a natural rubber or a synthetic rubber. S is formed into a hollow shape formed inside.

Then, as shown in FIG. 1, the rubber core 1 is disposed 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, a fluid such as a gas or a liquid (the present embodiment) is inserted into a flow path S formed in the rubber core 1. 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, so that the rubber core 1 In the state where the original shape is maintained without deforming
Is cast.

Subsequently, as shown in FIGS. 2 and 3, the casting 6 formed as described above is taken out of the mold 4 to terminate the casting, and to remove the burrs of the casting 6. Unnecessary parts can be removed to obtain a finished product.

In this case, since the temperature of the molten metal is considerably lower than the initial temperature before reaching the cavity 5 of the mold 4, the temperature of the rubber core 1 is reduced by the forced cooling by the fluid. When the molten metal acts due to its own temperature and latent heat, together with the reduction and the improvement of the pressure resistance, the initial shape is maintained without being immediately melted by the reflection action and the temperature action even if the molten metal acts. be able to.

FIG. 6 shows a third embodiment of the special core used in the present invention, in which a special core made of a fibrous material such as paper (hereinafter referred to as "paper core") is used. Will be described.

That is, the special core paper core 1 is
Using a fibrous material such as paper, an inlet S1 for continuously flowing a fluid such as a gas or a liquid as well shown in FIG.
And a flow path S having an outlet S2 is formed into a hollow shape formed inside.

Then, as shown in FIG. 1, 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. 1 and FIG. 2, a fluid such as a gas or a liquid (in this embodiment, While continuously flowing air), a molten metal such as an aluminum molten metal is poured into the cavity 5 formed in the mold 4 according to the material of the casting,
While maintaining the original shape without deforming the paper core 1, a casting 6 having a shape corresponding to the shape of the cavity 5 is cast.

Subsequently, as shown in FIGS. 2 and 3, the casting 6 formed as described above is removed from the mold 4 to terminate the casting, and to remove burrs and the like of the casting 6. Unnecessary parts can be removed to obtain a finished product.

In this case, since the temperature of the molten metal is considerably lower than the initial temperature before reaching the cavity 5 of the mold 4, the temperature of the paper core 1 is reduced by the forced cooling by the fluid. When the molten metal acts due to its own temperature and latent heat, together with the reduction and the improvement of the pressure resistance, the initial shape is maintained without being immediately melted by the reflection action and the temperature action even if the molten metal acts. be able to.

The special core used in the present invention is not limited to the materials and shapes of the above embodiments, but can be applied to various shapes using various special cores. The present invention is not limited to the resin core shown in the above embodiment, a rubber core such as natural rubber or synthetic rubber, or a paper core made of a fibrous material such as paper. By molding a molded product while continuously flowing a fluid such as a gas or a liquid therein, a core having both reciprocal conditions of pressure resistance during molding and heat dissipation after molding may be used. Many kinds of core materials and core shapes can be considered, such as a low melting metal such as tin, lead, antimony or the like, and the same effect as in the above embodiment can be obtained.

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

As described above, the present invention is based on the idea of improving the productivity and expanding the applicable range by using a molding method using a special core, and has the following effects. (1) Since a molded article is formed while a fluid such as a gas or a liquid is continuously flowed into the core, the core is pressurized in a state where a fluid such as a gas or liquid is continuously flown therein. As long as conditions such as heat resistance and heat resistance are satisfied, conditions such as pressure resistance and 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 fluid temperature of a fluid such as a gas or a liquid that flows continuously inside the core. (3) By using a special core as the core, the molding of the core is facilitated, the molding equipment is simplified, the number of steps is reduced, and the time and cost can be reduced. (4) Since a special core is used as the core, it is easy to handle because it does not break when dropped or thrown, making it easier to transport and store, reducing man-hours, and reducing time and costs. it can. (5) Since the special core used does not contain a penetrating component such as a binder, the core component is prevented from penetrating into the molded product, thereby preventing the occurrence of troubles such as the occurrence of voids and forming. The occurrence of defective products is prevented, and the yield and the productivity can be improved. (6) By using a special core as the core, it is easy to form a hollow portion or an undercut portion, and the core strength is improved. In this way, it is possible to expand the applicable range. (7) By using a core that has the reciprocal conditions of the pressure resistance during molding and the heat dissipation property after molding, it is possible to avoid problems such as insertion of a molten metal during molding and to achieve pressure resistance (non-disintegration). And facilitates the heat dissipation of the core after molding and the complete removal of the core component, preventing adhesion to the molded product and preventing the occurrence of molded product defects such as abrasion and breakage of the molded product. Can be achieved. (8) The special core does not contain components that are difficult to remove, such as a binder, and has heat dissipation properties after molding.
The complete removal of the core is facilitated, and the occurrence of pollution can be prevented. In addition, the number of steps can be reduced, and the time and cost can be reduced.

The special core used in the present invention is not limited to the materials and shapes of the above embodiments, but can be applied to various shapes using various special cores. The present invention is not limited to the resin core, the rubber core, and the paper core shown in the above embodiment. By molding the molded article, it is sufficient if the core has the reciprocal condition of the pressure resistance at the time of molding and the heat dissipation property after molding, and many modifications can be considered. Obtainable.

The molding method using the special core of the present invention is not limited to the die casting method as one of the casting methods described in the above embodiments, but may be obtained by adding a specific process to the die casting method. Further, it is possible to improve the quality of the cast product and the like. The present invention is not limited to the casting method of the above-described embodiment, and many variations can be considered, and the same effects as those of the above-described embodiment can be obtained.

Further, in the above embodiment, the case of performing die casting as one of the casting methods has been described.
The molding method using the special core of the present invention is not limited to the die casting, but can be applied to a sand casting gravity casting method, a mold gravity casting method, a low pressure casting method, a precision casting method, and other casting methods. Needless to say, excellent effects similar to those of the above 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, since the residence time of the molten metal during casting is longer than that of other casting methods, the contact time of the molten metal with 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. However, the special core 1 is used to form a molded article while continuously flowing a gas or liquid into the core. By doing so, heat exchange is performed by forcibly cooling the core, so that the heat resistance of the molten metal is significantly improved and the pressure resistance can also be significantly improved. Can maintain the initial shape without thermal deformation and contribute to the formation of the intended cast product 6.

At this time, a gravity casting method which is a fourth embodiment of the molding method using the special core of the present invention will be described with reference to FIGS.

That is, in the present embodiment, when a casting method of casting a casting by gravity casting using a special core is performed, one of them is to use a synthetic resin core as the special core. The case will be described.

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

First Step First, although not shown, a fluid such as a gas or a liquid as shown in FIG. 4 is continuously produced by using a synthetic resin by a synthetic resin molding method such as injection molding. A resin core 1 having a hollow shape in which a flow path S having an inlet S1 and an outlet S2 for flowing is formed is formed.

In the second step, as shown in FIG. 1, the inflow port S1 and the inflow port 7 provided in the lower
The resin core 1 is disposed between the upper mold 2 and the lower mold 3 by matching the outlet S2 and the mold 4 having the cavity 5.

Third Step 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 supplied to the inflow hole 7. The fluid flows continuously through the flow path S by flowing through the flow path S through the flow path S and flowing out from the outflow hole 8 and the flow outlet S2.

Thus, the resin core 1 is forcibly cooled, the pressure resistance when the molten metal is poured is maintained, deformation is prevented, and the original shape is maintained.

Fourth Step Next, as shown in FIGS. 1 and 2, while a fluid such as a gas or a liquid (in this embodiment, compressed air) is continuously passed through the flow path S, A molten metal such as an aluminum molten metal is poured into the cavity 5 formed in the mold 4 according to the material of the casting.

Thus, the resin core 1 is connected to the flow path S
Since the heat exchange is performed by forcibly 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 by pouring, 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 molten aluminum) until the temperature reaches the cavity 5 of the mold 4. The resin core 1 reduces its temperature due to the forced cooling by the fluid and improves the pressure resistance, so that even if the molten metal acts due to its own temperature and latent heat, the resin core 1 has a reflection function and a temperature. By the action, the initial shape can be maintained without immediately melting.

For this reason, a casting 6 having a shape corresponding to the shape of the hollow portion 5 is cast while maintaining the original shape without deforming the resin core 1.

The resin core 1 retains its shape at the time of casting, thereby contributing to the formation of the desired cast product 6 and, after casting, is melted by the residual heat of the cast product 6. As it is completely removed and eliminated, no residue remains.

Subsequently, as shown in FIGS. 2 and 3, the casting 6 formed above is removed from the mold 4 to complete the casting.

As described above, even in the gravity casting method, the special core 1 maintains its shape at the time of casting, thereby contributing to the formation of an intended cast product 6 and at the same time after casting. Since the cast product 6 is melted and removed by the residual heat to be eliminated, there is no residue left, the core can be completely removed after casting, and problems such as wear and breakage of the product can be prevented. And time and money 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 mixture of gas and liquid.
The pressure resistance and heat resistance of the core can be adjusted by adjusting the flow rate and the fluid temperature.

Further, even when the casting method as one of the molding methods using the special core of the present invention is performed, the special core of the above embodiment, the die casting method or the gravity casting method of the above embodiment may be used. The present invention is not limited to each embodiment of the present invention, but can be applied to low pressure casting, precision casting, and other casting methods. be able to.

The molding method using the special core of the present invention is not limited to the casting described in each of the above embodiments, but can be applied to molding methods other than the casting.

That is, according to the present invention, a special mold is used as a core to form a molding die such as a plastic molding die or a ceramic molding die, and a gas or gas is formed in a flow path formed inside the special core. While continuously flowing a fluid such as a liquid, a molded product such as a plastic molded product or a ceramic molded product can be molded using the molding die.

The special core 1 retains its shape at the time of molding, thereby contributing to the formation of the desired molded product. After molding, the special core 1 is melted by the residual heat of the molded product. Since it is removed and eliminated, there is no residue left, and the complete removal of the core of the molded product is easy, preventing problems such as abrasion and breakage of the product, improving the yield, and further increasing the time and cost. This can save money and improve productivity.

Further, the molding method using the special core of the present invention is not limited to each of the molding methods described above, and it is possible to further improve the quality of a molded article by adding a specific step. The present invention is not limited to the method, and many modifications can be considered.

[0082]

As described above, the present invention is based on the idea that a molding method using a special core is intended to improve the productivity and expand the applicable range and to obtain a molded product excellent in quality. It has the following excellent effects. (1) Since a molded article is formed while a fluid such as a gas or a liquid is continuously flowed into the core, the core is pressurized in a state where a fluid such as a gas or liquid is continuously flown therein. Since conditions such as heat resistance and heat resistance may be satisfied, conditions such as pressure resistance and heat resistance required for the core are relaxed, 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 fluid temperature of a fluid such as a gas or a liquid that flows continuously inside the core. (3) By using a special core as the core, the molding of the core is facilitated, the molding equipment is simplified, the number of steps is reduced, and the time and cost can be reduced. (4) Since a special core is used as the core, it is easy to handle because it does not break when dropped or thrown, making it easier to transport and store, reducing man-hours, and reducing time and costs. There are advantages that can be done. (5) Since the special core used does not contain a penetrating component such as a binder, the core component is prevented from penetrating into the molded product, thereby preventing the occurrence of troubles such as the occurrence of voids and forming. There is an advantage that the occurrence of defective products can be prevented and the yield and the productivity can be improved. (6) By using a special core as the core, it is easy to form a hollow portion or an undercut portion, and the core strength is improved. This has the advantage that the shape can be formed and the applicable range can be expanded. (7) By using a core that has the reciprocal conditions of the pressure resistance during molding and the heat dissipation property after molding, it is possible to avoid problems such as insertion of a molten metal during molding and to achieve pressure resistance (non-disintegration). And facilitates the heat dissipation of the core after molding and the complete removal of the core component, preventing adhesion to the molded product and preventing the occurrence of molded product defects such as abrasion and breakage of the molded product. There is an advantage that can be achieved. (8) The special core does not contain components that are difficult to remove, such as a binder, and has heat dissipation properties after molding.
There is an advantage that the core can be completely removed easily, pollution can be prevented, the number of steps can be reduced, and time and cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a method of forming a mold using a resin core among molding methods using a special core according to one embodiment of the present invention.

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

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

FIG. 4 is a sectional view showing a resin core used in a molding method using a special core according to one embodiment of the present invention.

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

FIG. 6 is a sectional view showing a third embodiment of the special core. Reference Signs List 1 special core (non-sand core) (resin core) (rubber core) (paper core) 2 upper die 3 lower die 4 molding die (mold) 5 cavity 6 molded product (cast product) 7 inflow hole 8 Outflow hole S Flow path S1 Inflow port S2 Outflow port

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI B29C 33/76 B29C 33/76 (56) References JP-A-4-189522 (JP, A) JP-A-7-1079 (JP) JP-A-61-293646 (JP, A) JP-A-4-66257 (JP, A) JP-A-63-101066 (JP, A) JP-A-6-87063 (JP, A) JP-A-6-87052 (JP, A) JP-A-3-99763 (JP, A) JP-A-2-142662 (JP, A) JP-A-63-260657 (JP, A) A) Japanese Patent Publication No. 51-41971 (JP, B2) Japanese Patent Publication No. 58-1299 (JP, B2) Japanese Patent Publication No. 3-37815 (JP, B2) (58) Fields surveyed (Int. Cl. ⁶ , DB name) ) B22D 17/22 B22C 9/04 B22C 9/10 B22D 23/00 B29C 33/12 B29C 33/76

Claims (8)

(57) [Claims] (1) The core has a melting point much lower than that of the molten metal.
Formed from sand material and completely different from the cast product which is completely removed and lost after casting
Comprising, forming a mold cast using Hisuna core, while flowing a fluid such as a gas or liquid at the time of casting the flow path of the tang having a flow path therein continuously, using the casting mold molding method using special core for molding a casting, it is characterized by Te. 2. The non-sand core has a pressure resistance by continuously flowing a fluid such as gas or liquid during casting.
To prevent deformation and deterioration during casting by improving heat resistance and heat resistance.
By molding while protecting the inner wall surface of the casting Te, the core having a reciprocal conditions of the heat fugitive after molding pressure resistance during molding, molded by using it, characterized in billing Item 6. A molding method using the special core according to Item 1. 3. The inner wall surface of a hollow portion such as a hollow shape or an undercut shape (cast
To protect the inner wall surface by covering the entire
Defective casting products such as molten metal insertion and casting cavities during casting
The special core according to claim 1 or 2 , wherein a casting having a cavity formed therein is formed by using a core for preventing generation.
Molding method using a child. 4. The high heat and high pressure of the molten metal during casting as a non-sand core.
Used for casting such as die casting
The casting according to any one of claims 1 to 3, wherein a casting having a hollow portion formed therein is formed using a core.
Molding method using special core. 5. A non-sand core, wherein the residence time of the molten metal at the time of casting becomes long, and
Casting the castings of gravity casting Hinto contact time is that a long with child
The core according to any one of claims 1 to 3, wherein the core is used to mold a casting having a cavity formed therein .
Molding method using special core. 6. The non-sand core does not deform even when high heat and high pressure of the molten metal at the time of casting act.
A core consisting of cormorants in inflexible and comprises synthetic resin (plastic), is molded by using, with a special core according to any one of claims 1 to 5, wherein the molding Method. 7. The non-sand core does not deform even when high heat and high pressure of the molten metal at the time of casting act.
A core consisting of rubber having a non-flexible in earthenware pots, formed using
Molding method using special core according to any one of claims 1 to 5 to form, it is characterized. 8. The non-sand core does not deform even when high heat and high pressure of the molten metal at the time of casting act.
A core made of a fibrous material such as paper having inflexibility ,
Molding method using special core according to any one of claims 1 to 5 for molding using, characterized in that.