JPH1015951A - Production of mold and production of packing material using mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with the use of a wood mold and to reduce the number of processes, by forming a mold model from a foamed resin decomposed by heat to disappear and introducing this mold model and molding sand into a casting frame to inject a molten metal. SOLUTION: When a molten aluminum 8 is injected from a gate 18, a mold model 15 made of foamed styrol coming into contact with molten aluminum 8 is scattered through a gas vent hole 19 and the gate 18. The mold model disappears by the injection of molten aluminum and the part of the mold model 15 embedded in molding sand 16 is replaced with molten aluminum 18. After cooling, a projected previous product 21 is taken out of the casting frame to be subjected to simple processing such as removing aluminum of an unnecessary part to complete a projected mold 3. In the case of a recessed mold 2, when molten aluminum is injected from the gate, the mold model 22 made of foamed styrol coming into contact with molten aluminum is decomposed to carbon dioxide and water to disappear and the part of the mold model 22 embedded in molding sand is substituted with molten aluminum and, after moling, aluminum is taken out of the casting frame to complete the recessed mold 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a mold required for manufacturing a shock absorbing packing material and a method of manufacturing a packing material using the mold.

[0002]

2. Description of the Related Art When packing various products into a packaging box, a packing material for shock absorption is interposed between the product and the packaging box. Specifically, as shown in FIG. 4 (a), a left-side packing material 1L having a concave portion 1a is fitted to the left side of the product according to the shape of the left side of the product, and is similarly shaped into the right side of the product. Accordingly, the right packing material 1R formed with the concave portion 1b is fitted to the right side of the product, and the product having the packing materials 1L and 1R attached to the left and right is packed in a packaging box.

A styrene resin is used as a raw material for a packing material. For manufacturing the packing materials 1L and 1R, two casting molds are required respectively. Since the same applies to any packing material, the case of the packing material 1L will be described here.

[0004] As shown in FIG.
And a convex mold 3 were prepared, beads of styrene foam 5 were put between the concave mold 2 and the convex mold 3, and steam 4 was blown into the mold.
As shown in (c) of FIG.

[0005] Packing material 1L or packing material 1R
In order to manufacture the concave mold 2 and the convex mold 3 made of the casting necessary for the production of the above, two wooden molds need to be produced as shown in FIGS.
FIG. 5 shows a manufacturing process of the convex mold 3.

[0006] In order to produce the casting-shaped convex mold 3 shown in FIG. 5D, a first sand mold 6 and a second sand mold 7 made of molding sand are used as shown in FIG. 5C. Then, a molten aluminum 8 is poured between the first and second sand molds 6 and 7.

[0007] To manufacture the first sand mold 6, as shown in FIG. 5 (a), a first wooden mold 9 having a recess 9 a formed along the shape of the first sand mold 6 and a second sand mold. The second wooden mold 10 in which the convex portion 10a is formed along the shape of FIG.
As shown in FIG. 1B, sand molds 6 and 7 are manufactured using the first mold 9 and the second mold 10.

FIG. 6 shows a manufacturing process of the concave mold 2. In the case of the concave mold 2, similarly to the case of the convex mold 3, third and fourth wooden molds 11 and 12 are produced as shown in FIG. 6A, and then as shown in FIG. Sand molds 13 and 14 are prepared using the third and fourth wooden molds 11 and 12, and a molten aluminum 8 is injected between the sand molds 13 and 14 as shown in FIG. A concave mold 2 is obtained as shown in FIG.

[0009]

In order to obtain one packing material as shown in FIG. 4A corresponding to the shape of the object to be packed, conventionally, four wooden molds 9, 10, 11, and 10 are used.
12 molding steps are required.

[0010] In addition, the sand mold 6,7,1
3 and 14 are required, and the injection of the molten metal 8 also requires two operations of FIG. 5 (c) and FIG. 6 (c). The present invention provides a mold manufacturing method that does not require the manufacture of a wooden mold requiring skill in the manufacture, and provides a mold required for manufacturing a packing material having a desired shape in fewer steps than before. Aim.

[0011]

According to the method of manufacturing a mold of the present invention, a mold model is produced from a foamed resin which is decomposed by heat and disappears, and the mold model and molding sand are placed in a casting flask to form a molten metal. To obtain a mold product having a desired shape.

According to the present invention, a mold required for manufacturing a packing material having a desired shape can be obtained without using a wooden mold and using fewer steps than in the conventional case.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The method of manufacturing a mold according to the first aspect is as follows.
A mold model of the desired shape is molded with a foamed resin, the mold model and the molding sand made of the foamed resin are put into a casting frame, and the casting sand is formed with a gate that communicates with the embedded mold model, Inject the molten metal from the gate and decompose the mold model with the heat of the molten metal,
The mold product is taken out of the flask after cooling.

According to a second aspect of the present invention, a mold model is formed from a foamed resin, and a part made of a material different from the foamed resin is attached to a part of the mold model, and the mold is placed in a molding frame together with molding sand. Forming a gate that communicates with the mold model buried in the molding sand, injecting the molten metal from the gate to decompose the mold model by the heat of the molten metal, and after cooling, integrate with the component from the casting flask It is characterized by taking out the mold product which has become the above.

According to a third aspect of the present invention, there is provided a method of manufacturing a packing material, comprising molding a mold model with a foamed resin, attaching a printing plate of a material different from that of the foamed resin to a part of the mold model, and forming a molding frame together with molding sand. Into the casting sand, forming a gate communicating with the mold model buried in the molding sand, pouring the molten metal from the gate, decomposing the mold model by the heat of the molten metal, cooling, and then cooling the mold from the mold. It is characterized in that the mold product integrated with the plate is taken out.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a packing material, wherein a concave shape and a convex shape required for molding the packing material are respectively formed when manufacturing the packing material according to the shape of the packaging object. It is manufactured by the mold manufacturing method according to claim 2 or 3, and a foaming resin is put between the completed concave mold and the convex mold to foam the foamed resin to obtain a target packing material.

Hereinafter, the mold manufacturing method of the present invention will be described based on specific embodiments. (Embodiment 1) FIG. 1 shows a manufacturing process for manufacturing a concave mold 2 and a convex mold 3 necessary for manufacturing a packing material (Embodiment 1).

In manufacturing the convex 3, first, as shown in FIG. 1A, a block of a styrofoam resin is cut into a three-dimensional mold model 15 based on 3D-CAD data of the convex 3. .

Next, this styrofoam mold model 15 is used.
The casting sand 16 is buried in a casting frame 17 as shown in FIG. 1B, and a gate 18 and a gas vent 19 are formed in the casting sand 16 as shown in FIG. 1C.

Next, as shown in FIG. 1 (d), when the molten aluminum 8 is poured from the gate 18, the mold model 15 made of styrene foam in contact with the molten metal 8 is decomposed into carbon dioxide and water, and is indicated by an arrow 20. As shown, vent 19 and gate 1
8, the mold model 15 disappears with the pouring, and the portion of the mold model 15 embedded in the casting sand 16 finally reaches the molten metal 8 as shown in FIG. Is replaced by

After cooling, the convex pre-product 21 is taken out of the casting flask 17, and unnecessary portions (gate 18 and gas vent 19) are removed.
The projection 3 shown in FIG. 1 (f) is completed only by simple processing such as removing aluminum.

In the case of the concave mold 2 as well, as shown in FIG.
The three-dimensional mold model 22 is cut based on the CAD data, and then the styrofoam mold model 22 and the molding sand 16 are buried in the casting frame 17 as in FIG. A gate and a gas vent are formed in the casting sand 16 in the same manner as in FIG. 1C, and the molten aluminum is poured from the gate in the same manner as in FIGS. 1D and 1E. The mold model 22 is decomposed into carbon dioxide gas and water, and the mold model 22 disappears. The part of the mold model 22 embedded in the molding sand is replaced with molten metal. The concave mold 2 shown in (h) is completed.

The thus completed concave mold 2 and convex mold 3
Styrofoam beads are put in between, and steam 4 is blown in to foam as shown in FIG. 4 to form a desired shape.

According to this mold manufacturing method, the work for handling the molding sand is performed only once by putting the mold models 15 and 22 and the molding sand 16 into the casting frame 17 without producing a difficult wooden mold. The number of steps can be significantly reduced as compared with the conventional method that required molding four times with molding sand to produce the concave mold 2 and the convex mold 3, and the workability is very good. It is.

(Embodiment 2) FIG. 2 shows (Embodiment 2)
Is shown. In (Embodiment 1), the thin portion 3b of the convex 3 is also integrally formed when the mold model 15 is manufactured, but is the molten metal 8 sufficiently wrapped around the portion where the thin portion of the mold model 15 has disappeared? Anxiety remains, (Embodiment 2)
Has improved this point.

In (Embodiment 2), as shown in FIG. 2A, a block of styrofoam resin is formed on the basis of 3D-CAD data of the convex 3 except for a portion corresponding to the thin portion 3b. A typical die model 15a is cut, and then, as shown in FIG. 2B, a thin-walled part 23 made of aluminum of the same material as the finished convex die 3 is set on the die model 15a. As shown in FIG. 2 (c), the mold model 15a on which the thin-walled parts 23 are set and the molding sand 16 are placed in a casting frame 17 and buried to form a gate 18 and a gas vent 19, as shown in FIG. When the molten metal 8 of aluminum is poured as shown in d), the mold model 15a disappears, the part of the mold model 15a embedded in the casting sand 16 is replaced by the molten metal, and the thin part 23 is removed by the molten metal 8 And integrated into . After the cooling, the convex preform 21 is taken out of the casting frame 17 and the convex 3 is completed only by performing simple processing such as removing aluminum in unnecessary portions (gate 18 and gas vent 19).

By setting the thin part 23 made of the same material as the finished convex mold 3 in advance in the mold model 15a, the thin part 3b of the convex mold 3 can be formed very accurately.

In this (Embodiment 2), the method for manufacturing a mold in the case where the convex mold 3 has a thin portion has been described as an example. However, the same can be applied to the case of the concave mold 2 having a thin portion. Beads of styrofoam resin are introduced between the concave mold 2 and the convex mold 3 completed in this way, and steam 4 is blown into the foam to form into a desired shape.

(Embodiment 3) The outer peripheral surface or the inner peripheral surface of the packing material indicates a place where the packing material is to be mounted.
There are characters recorded as “left”, “right”, “LEFT”, “RIGHT”, and the signs “front”, “rear”, “→”, “←” indicating the mounting direction are concave or convex on the surface.

(Embodiment 1) (Embodiment 2)
In such a case, it is uneasy to record such characters or codes in a concave or convex shape on the surface. However, (Embodiment 3) improves this point.

FIG. 3 shows (Embodiment 3). In the third embodiment, as shown in FIG. 3A, the block of the styrofoam resin is formed in a convex shape 3 except for a portion corresponding to the thin portion 3b and a place where the characters and codes are recorded. Three-dimensional mold model 15a based on 3D-CAD data
Then, the thin-walled parts 23 and the printing plate 24 prepared in advance are set on the mold model 15a as shown in FIG. 2 (b).

Each of the thin-walled component 23 and the printing plate 24 is processed with aluminum of the same material as the finished convex mold 3, and the printing plate 24 has a printing surface on which projections and depressions are formed in accordance with characters and codes to be recorded. 25 is set on the mold model 15a so as to be on the lower side in this example.

The mold 15a and the molding sand 16 on which the thin-walled parts 23 and the printing plate 24 are set are put into a casting frame 17 as shown in FIG. When the molten aluminum 8 is poured as shown in FIG. 3D, the mold model 15a disappears and the mold model 15a embedded in the molding sand 16 is replaced with the molten metal. The thin part 23 and the printing plate 24 are melted into the molten metal 8 and integrated. After cooling, the convex pre-product 21 is taken out of the flask 17 and is removed from unnecessary portions (the gate 18,
The convex 3 is completed only by simple processing such as removing aluminum from the gas vent 19).

By setting the printing plate 24 made of the same material as that of the finished convex mold 3 in the mold model 15a in this manner, the printing plate surface 25 can be formed very accurately on the convex mold 3.

In this (Embodiment 3), the mold manufacturing method in the case where the convex mold 3 has the printing plate surface 25 has been described as an example. However, the same can be applied to the case where the concave mold 2 has the printing plate surface. . Necessary characters and codes were recorded by introducing beads of styrofoam resin between the concave mold 2 and the convex mold 3 completed in this way, blowing water vapor 4 and foaming to form a desired shape. The packing material can be manufactured reliably.

In the above embodiment, (Embodiment 2)
Although the case where the stamping plate 24 is attached to the die and the packing material is formed is described as an example, the stamping plate 24 is similarly attached to the completed mold as in (Embodiment 1) and the same. A packing material can also be formed.

In the above embodiment, styrene foam was used as an example of the foamed resin, but foamed polyethylene, foamed styrene, urethane foam, or the like can be used in the same manner.

[0038]

As described above, according to the present invention, a mold model having a desired shape is molded from a foamed resin, the mold model made of the foamed resin and molding sand are put into a casting frame, and a molten metal is injected. Since the mold product is manufactured by decomposing the mold model by the heat of the molten metal, it is possible to obtain the mold product without producing a wooden mold as in the related art and with fewer steps than in the related art.

Further, a mold model is molded with a foamed resin, a part made of a material different from that of the foamed resin is attached to a part of the mold model, put into a casting frame together with molding sand, and a molten metal is injected to mold the mold model. Is manufactured by decomposing with the heat of molten metal, it is possible to accurately form even a thin portion.

Further, a mold model is molded with a foamed resin, a printing plate made of a material different from that of the foamed resin is attached to a part of the mold model, and the mold is put into a casting frame together with molding sand. In the case where a sprue communicating with the mold model is formed, and the molten metal is poured from the sprue and the mold model is decomposed by the heat of the molten metal, it is possible to accurately form even the printing plate surface.

Further, the concave mold and the convex mold are manufactured by the mold manufacturing method according to claim 1, 2 or 3, respectively, and a foamed resin is put between the completed concave mold and the convex mold to uniformly foam. In the case where the packing material is manufactured by the method, the manufacturing process of the packing material that needs to be changed in shape according to the packaging object can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a process chart showing a mold forming process according to a first embodiment.

FIG. 2 is a process diagram showing a mold forming process according to a second embodiment.

FIG. 3 is a process diagram showing a main part of a mold forming process according to a third embodiment.

FIG. 4 is a process chart showing a molding process of the packing material.

FIG. 5 is a process diagram showing a conventional mold forming process.

FIG. 6 is a process diagram showing a conventional mold forming process.

[Explanation of symbols]

 2 Concave type 3 Convex type 3b Thin part of convex type 3 4 Steam 8 Melt 15, 15a Mold model made of foamed resin 16 Casting sand 17 Casting frame 18 Gate 19 Gas vent 21 Pre-convex product 22 Mold model 24, 25 Printing plate

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Seiichi Fujimoto 3-13-9 Nishitenma, Kita-ku, Osaka-shi, Osaka Nishitenma Park Building No.4 Dairyu Kasei Co., Ltd. In-house (72) Inventor Eimoto Yamamoto Kita, Osaka-shi, Osaka 3-13-9 Nishitenma-ku Nishitenma Park Building No.4 Dairyu Kasei Co., Ltd.

Claims (4)

[Claims] 1. A mold model having a desired shape is molded with a foamed resin, and the mold model made of the foamed resin and a molding sand are put into a casting frame, and communicated with a mold model buried in the molding sand. A mold manufacturing method for forming a gate, injecting the molten metal from the above-mentioned gate, decomposing the mold model by the heat of the molten metal, and removing the mold product from the casting frame after cooling. 2. A mold model is molded from a foamed resin, a part made of a material different from that of the foamed resin is attached to a part of the mold model, and is put into a casting frame together with molding sand. Forming a gate that communicates with the mold model that is present, injecting the molten metal from the gate, decomposing the mold model by the heat of the molten metal, and removing a mold product integrated with the component from the casting frame after cooling. Mold manufacturing method. 3. A mold model is molded from a foamed resin, a stamping plate of a material different from that of the foamed resin is attached to a part of the mold model, and the mold is placed in a molding frame together with molding sand. Forming a gate that communicates with the mold model that is being poured, injecting the molten metal from the gate to decompose the mold model by the heat of the molten metal, and cooling the mold product integrated with the stamping plate from the casting frame. Mold manufacturing method to take out. 4. A mold according to claim 1, 2 or 3, wherein a concave mold and a convex mold required for molding the packing material are manufactured when manufacturing the packing material according to the shape of the packaging object. A method for producing a packing material which is produced by a production method, and a foaming resin is put between a completed concave mold and a convex mold and foamed to obtain a target packing material.