JPH06320252A - Manufacture of forming die having heating and cooling water line - Google Patents

Abstract

PURPOSE:To form a heating and cooling water line having the roughness of collapsible sand in a forming die by pouring the molten metal into the cavity part of the die to cast in the metallic tube by melting, and collapsing and removing the collapsible residual sand only after the molten metal poured into the cavity part is solidified. CONSTITUTION:A metallic tube of the prescribed shape where collapsible sand 16 is packed is provided at the prescribed position within the cavity part 28 of a die. When the molten metal is poured into the cavity part 28 for the product, the temperature of the metallic tube reaches the melting point and is fused in the molten metal. Which means, the metallic tube is melted into the molten metal to be cast in, and integrated therewith. When the poured metal is cooled for the prescribed period of time, the molten metal in the cavity part 28 for the product is solidified to make the die 28 for the product. When the molten metal is poured into the cavity part 28 for the product, the collapsible sand 16 packed in the die 28 for the product loses the caking property by the heat of the molten metal, and falls down to make the casting die having the heating and cooling water pipe 34 in the die 28.

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 or resin molding die.

[0002]

2. Description of the Related Art FIGS. 4 and 5 show sectional views of a conventional mold. Figure 4 shows a mold 1 manufactured by machining or casting,
The holes 2 for heating or cooling medium passages have been formed at desired locations using a drilling tool such as a drill. Further, FIG. 5 shows that a metal tube 5 having a good thermal conductivity is integrally cast in the vicinity of the surface of the mold by the cast-in-hole casting method, and the heating or cooling medium passage hole 3 is formed.
Had formed.

[0003]

However, in the case of manufacturing the molding die described above, first, when the heating or cooling medium passage hole 2 is formed in the die 1 as shown in FIG. 4, Since the heating or cooling medium passage hole 2 can be processed only in a straight line, uneven heating or cooling occurs in the uneven portion of the die molding surface. As a result, molding surface defects, deformation, seizure, and other molding defects occur. Since the heating or cooling medium passage hole 2 cannot be arranged along the mold forming surface in the vicinity of the surface of the mold forming surface, it takes time to heat and cool the mold forming surface, and the molding support ( 2) The ukule becomes longer. When the die molding surface has a complicated shape, machining is extremely difficult and the processing cost is high.

Next, as shown in FIG. 5, when the heating or cooling medium passage hole 3 is formed in the mold 1 by the cast-in-girth method, for example, a cast-in alloy with good thermal conductivity such as a copper pipe is used. Since the metal pipe 5 causes an alloying reaction with the molten metal injected during casting (aluminum of the molten metal reacts with the copper pipe to melt the copper pipe) and melts instantaneously, the heating or cooling medium passage hole 3 is formed. It is extremely difficult to form. Therefore, a melting loss prevention treatment step of forming a heat-resistant coating layer or the like on the surface of the cast metal pipe 5 in advance is required, and the die manufacturing process becomes complicated. Further, since the melt damage prevention treatment is performed, the heat resistant coating layer remains in the minute gap between the cast metal pipe 5 and the mold 1, and as a result, it takes time to heat and cool the mold molding surface.
Longer molding cycle. There was such a problem.

In the present invention, focusing on the above-mentioned conventional problems, a molten metal is poured into a cavity portion and completely melted with a cast metal pipe, and heating is performed in a molding die with roughness of collapsible sand. -The purpose is to form cooling passage holes.

[0006]

In order to achieve the above object, a method for manufacturing a molding die having heating / cooling passage holes according to the present invention is a metal pipe having a predetermined shape filled with collapsible sand. Installed in a predetermined position in the cavity of the mold, the molten metal is injected into the cavity of the mold to cast the metal pipe by melting, and only the collapsible sand remaining after solidification of the molten metal injected into the cavity is collapsed and removed. Thereby, the heating or cooling medium passage hole is formed.

Page (3)

The metal pipe which is deformed into a predetermined shape and is filled with collapsible sand is placed in the cavity of the mold. Then, the molten metal is poured into the cavity portion to completely melt the cast metal and the cast metal to form a seamless integral mold. By doing so, efficient heating and cooling can be performed without using a metal pipe as in the conventional case.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A concrete embodiment of a method for manufacturing a molding die having heating / cooling passage holes according to the present invention will be described below with reference to the drawings.

First, as shown in FIG. 1 (1), the present inventors 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 attached to 0a, the blind plug 14 side is lowered to stand up, and the preliminarily prepared collapsible sand 16 is charged from the charging container 18 from the other end 10b in the open state (Fig. 1).
(2)). During the filling of the aluminum pipe 10 with the collapsible sand 16 or after completion of the filling, the aluminum pipe 10 is filled with vibration within a predetermined bulk density range while vibrating as necessary.

When the collapsible sand 16 is filled in 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. 2 (1)). Then, the solidified collapsible sand 16 in the aluminum pipe 10 is attached to the lower mold frame 20a as shown in FIG. 2 (2), and then the molten aluminum alloy 22 at 700 to 740 ° C. is pumped into the ladle 24, for example. Pour as shown in FIG. Here, reference numeral 20b is an upper mold frame, 26 is a ceramic portion, 28 is a product cavity portion, and 30 is 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 portion 12 is set to, for example, 10 to 30 mm, and a plurality of aluminum pages (4) aluminum pipes 10 are attached. 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 portion 28 as described above, the aluminum pipe 10 reaches the melting temperature and is fused to the molten aluminum alloy 22. That is, aluminum pipe 1
0 is melted in the molten aluminum alloy 22 and cast around,
It is integrated with this. (FIG. 3 (1)). In this way, 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 formed. After that, the feeder unit 32 is cut into the product mold 28 in FIG.

Disintegrating sand 1 filled inside the product mold 28
6 is the aluminum alloy melt 22 and the product cavity portion 28
When it is poured into the mold, it loses its caking property due to the heat of the molten metal, and when the product mold 28 is erected, the collapsible sand 16 collapses and falls, as shown in FIG. A casting mold 28 having a heating or cooling passage hole 34 is formed (FIG. 3 (3)). Collapsible sand 1 in the product mold 28 described above
When removing 6, the product mold 28 may be vibrated.

The various conditions of the embodiment shown in FIGS. 1 to 3 are as follows: cast gurney pipe outer 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; Phenolic resin addition amount 0.8 to 1 .8% Page (5) Disintegration aid; Addition amount of organic acid alkali metal salt (eg, Ca acetate, Zu acetate) 3% Curing conditions: Heating at 200 ° C. for 10 to 30 minutes. Disintegration condition: Disintegration is improved by heat of molten metal during injection of molten aluminum alloy.

In this embodiment, heating and cooling passage holes 34 are provided.
Although they are arranged at the same pitch, the pitch may be changed according to the complexity of the mold cavity portion 12. Further, the cast stuffed pipe is the aluminum pipe 10 having a small heat capacity, but the cast product material of the product mold part 28 is a material equivalent to SKD61, and the cast stuffed material at this time is a carbon steel pipe for JIS piping (SGP). Product mold 2 by the same method as this embodiment.
A heating / cooling passage hole 34 may be provided in the inside 8.

[0015]

As is apparent from the above description, in the present invention, a metal pipe having a predetermined shape filled with collapsible sand is installed at a predetermined position in the cavity of the mold, and the molten metal is poured into the cavity of the mold. By casting the metal pipe by melting the metal pipe, by collapsing and removing only the collapsible sand remaining after the solidification of the molten metal poured into the cavity, by heating or cooling medium passage holes are formed,
Since the molten metal and the metal pipe are completely melted and integrally formed, the thermal conductivity during heating or cooling is significantly improved. In addition, since the mold is forcibly cooled by flowing the heating / cooling medium through the heating / cooling passage hole provided at the predetermined position, the heat input / output to / from the mold can be effectively controlled and removed, and the life of the mold is extended. Not only can it raise the quality level of the products made by the mold.

[Brief description of 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 cross-sectional view of a conventional mold.

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

[Explanation of symbols]

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

Claims (1)

[Claims] 1. A metal pipe having a predetermined shape filled with collapsible sand is installed at a predetermined position in a cavity of a mold, and a molten metal is injected into the cavity of the mold to melt the metal pipe to form a cavity. Of a mold for heating and cooling passages, characterized in that the heating or cooling medium passage holes are formed by disintegrating and removing only the disintegrating sand remaining after solidification of the molten metal injected into the part Method.