JP3053042B2 - Manufacturing method of molding die having heating / cooling passage hole - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a metal mold or resin mold.

[0002]

2. Description of the Related Art FIGS. 4 and 5 show sectional views of a conventional mold. FIG. 4 shows a mold 1 manufactured by machining or casting.
The hole 2 for a heating or cooling medium passage is formed at a desired place using a drilling tool such as a drill. FIG. 5 shows a case where a metal tube 5 having good thermal conductivity is integrally cast in the vicinity of the surface of a mold by insert molding to form a heating or cooling medium passage hole 3.
Had formed.

[0003]

However, when manufacturing the above-described molding die, first, when a hole 2 for a heating or cooling medium passage is formed in the die 1 as shown in FIG. Since the heating or cooling medium passage hole 2 can be processed only linearly, unevenness in heating and cooling occurs at the concave and convex portions of the mold forming surface. As a result, molding defects such as poor surface properties of the molded product, deformation, and seizure occur. Since the heating or cooling medium passage hole 2 cannot be arranged near the surface of the mold molding surface along the mold molding surface, it takes time to heat and cool the mold molding surface, and the molding support ( 2) The cycle becomes longer. When the molding surface has a complicated shape, machining is extremely difficult and the machining cost is high.

Next, as shown in FIG. 5, when a hole 3 for a heating or cooling medium passage is formed in a mold 1 by a cast-in method, for example, a heat-conductive mold such as a copper pipe is used. Since the metal pipe 5 causes an alloying reaction with the molten metal injected during casting (the aluminum and the copper pipe of the molten metal react with each other to melt the copper pipe) and instantaneously melts, the heating or cooling medium passage hole 3 is formed. It is extremely difficult to form. Therefore, a erosion prevention process for forming a heat-resistant coating layer or the like on the surface of the metal pipe 5 is necessary in advance, which complicates the mold manufacturing process. Furthermore, due to the erosion prevention treatment, the heat-resistant coating layer remains in the minute gap between the metal pipe for casting 5 and the mold 1, and as a result, it takes time to heat and cool the molding surface of the mold.
The molding cycle becomes longer. There was such a problem.

The present invention focuses on the above-mentioned conventional problems, and injects a molten aluminum alloy into a cavity to form a casting.
An object of the present invention is to completely melt an aluminum pipe to form a heating / cooling passage hole having a roughness of collapsible sand in a molding die.

[0006]

To achieve the above object, according to the Invention The method for producing a mold having a heating and cooling passage holes according to the present invention, aluminum having a predetermined shape filled with disintegrating sand
The beam pipe was set at a predetermined position in the mold cavity, the melting point of the aluminum pipe into the cavity of the mold
Injecting a higher temperature aluminum alloy melt
Cast aluminum pipe, the aluminum alloy
The molten metal and the aluminum pipe are completely melted and integrally formed
Then, only the collapsible sand remaining after solidification of the aluminum alloy melt injected into the cavity is collapsed and removed to form the heating or cooling medium passage hole.

[0007]

An aluminum pipe deformed into a predetermined shape and filled with collapsible sand is placed in a cavity of a mold. Next, the aluminum pipe is inserted into the cavity.
Inject molten aluminum alloy at a temperature higher than the melting point
Casting is performed by complete melting with the aluminum pipe, and a seamless integrated mold is produced. By doing so, efficient heating and cooling can be performed without using a metal pipe as in the related art.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a specific embodiment of a method of manufacturing a molding die having a heating / cooling passage hole according to the present invention will be described with reference to the drawings.

First, as shown in FIG. 1A, the present inventors, for example, bend a pure aluminum pipe 10 (melting point: 650 ° C.) into a similar shape along the cavity 12 on the surface of the mold 1. One end 1 of the aluminum pipe 10
After the blind plug 14 is placed at 0a, the blind plug 14 is erected with the blind plug 14 side downward, and the disintegrable sand 16 prepared in advance is charged from the charging container 18 from the open end 10b (FIG. 1).
(2)). During or after the filling of the collapsible sand 16 into the aluminum pipe 10, the aluminum pipe 10 is filled within a predetermined bulk density range while vibrating as necessary.

When the collapsible sand 16 is filled with the aluminum pipe 10 and heated at a temperature of about 200 ° C. for 10 to 30 minutes, the collapsible sand 16 is solidified (FIG. 2A). Next, after the collapsible sand 16 solidified in the aluminum pipe 10 is attached to the lower mold frame 20a as shown in FIG. Pour in as shown in FIG. Here, reference numeral 20b denotes an upper mold frame, 26 denotes a ceramic portion, 28 denotes a product cavity portion, and 30 denotes a casting sand portion.
The aluminum pipe 10 in which the collapsible sand 16 is solidified
When the aluminum pipe 10 is attached to the lower mold frame 20a, the depth from the outer surface of the aluminum pipe 10 to the mold cavity 12 is, for example, 10 to 30 mm, and a plurality of aluminum pipes (4) If installed, aluminum pipe 1
The arrangement pitch of 0 is, for example, 25 mm.

When the molten aluminum alloy 22 is injected into the product cavity 28 as described above, the aluminum pipe 10 reaches the melting temperature and is fused to the molten aluminum alloy 22. In other words, aluminum pipe 1
0 is melted and cast into the aluminum alloy melt 22,
It is integrated with this. (FIG. 3 (1)). Thus, when the injected aluminum alloy 22 is cooled for a predetermined time,
A so-called product mold 28 in which the molten metal 22 in the product cavity 28 is solidified is obtained. Thereafter, the feeder portion 32 is cut in FIG.

Disintegrable sand 1 filled inside the product mold 28
6 is a process in which the molten aluminum alloy 22 is supplied to the product cavity portion 28.
When the product is poured into the mold, the caking property is lost due to the heat of the molten metal, and as shown in FIG. 3 (2), when the product mold 28 is raised, the collapsible sand 16 collapses and falls, and falls into the mold 28. Thus, a casting mold 28 having a heating or cooling passage hole 34 is formed (FIG. 3 (3)). Collapseable sand 1 in the above-mentioned product mold 28
When removing 6, the product mold 28 may be vibrated.

Here, the conditions of the embodiment shown in FIGS. 1 to 3 are as follows: Cast-in pipe External shape: 10 to 16 mm (wall thickness: 1.0 to 2.0 mm) Material: Pure aluminum (melting point: 650 ° C.) Mold part Aluminum alloy (melting temperature; 700 to 740 ° C) Material: Aluminum alloy (AC4C) Composition of collapsible sand Filler; Resin-coated sand Average particle size 90 µm: 20 µm = 2: 3 binder; 0.8% Page (5) Disintegration aid; Organic acid alkali metal salt (for example, Ca acetate, Zu acetate) added 3% Curing condition: Heating at 200 ° C. for 10 to 30 minutes. Disintegration conditions: Disintegration is improved by the heat of the molten aluminum alloy during casting.

In the present embodiment, the heating and cooling passage holes 34
Are arranged at the same pitch, but the pitch may be changed according to the degree of complexity of the mold cavity 12.

[0015]

As is evident from the above description, in the present invention, aluminum of predetermined shape filled with collapsible sand is used.
The beam pipe was set at a predetermined position in the mold cavity, the melting point of the aluminum pipe into the cavity of the mold
Injecting a higher temperature aluminum alloy melt
Cast aluminum pipe, the aluminum alloy
The molten metal and the aluminum pipe are completely melted and integrated
Heating or cooling medium passage holes are formed by collapsing and removing only the collapsible sand remaining after solidification of the aluminum alloy melt injected into the cavity, so that the aluminum alloy melt and the aluminum pipe are completely melted. Since they are integrally formed, the thermal conductivity during heating or cooling is greatly improved. In addition, since the mold is forcibly cooled by flowing a heating / cooling medium through the heating / cooling passage hole provided at a predetermined position, it is possible to effectively control the flow of heat into and out of the mold, and to prolong the life of the mold. In addition, it can raise the quality level of products made with molds.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a method for manufacturing a molding die according to the present invention.

FIG. 2 is an explanatory view showing a method for manufacturing a molding die according to the present invention.

FIG. 3 is an explanatory view showing a method for manufacturing a molding die according to the present invention. Page (6)

FIG. 4 is a sectional view of a conventional mold.

FIG. 5 is a sectional view of a conventional mold.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Aluminum pipe 12 Cavity part 16 Collapseable sand 20 Mold frame 22 Aluminum alloy molten metal 26 Ceramic part 28 Product mold part 30 Casting sand part 34 Heating or cooling passage hole

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-60-3960 (JP, A) JP-A-60-133966 (JP, A) JP-A-4-197569 (JP, A) JP-A-3-3 142058 (JP, A) JP-A-3-142057 (JP, A) JP-A-60-184460 (JP, A) JP-A-3-60858 (JP, A) JP-A-4-305351 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) B22D 19/06 B22D 19/00

Claims (1)

(57) [Claims] 1. An aluminum having a predetermined shape filled with collapsible sand
The beam pipe was set at a predetermined position in the mold cavity, the melting point of the aluminum pipe into the cavity of the mold
Injecting a higher temperature aluminum alloy melt
Cast aluminum pipe, the aluminum alloy
The molten metal and the aluminum pipe are completely melted and integrally formed
The heating or cooling medium passage hole is formed by collapsing and removing only the collapsible sand remaining after the aluminum alloy melt solidified injected into the cavity, thereby forming a heating or cooling passage hole. Mold manufacturing method.