JPH09254196A - Manufacture of plastic injection molding die - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a mold having long service life at low cost with which delivery time can be shortened and no defective shapes are produced. SOLUTION: A prototype model 1 is manufactured, an ultra-plastic material 2 is preheated, the prototype model 1 and the ultra-plastic material 2 are set in a formwork 4 so as to change the ultra-plastic material 2 to the shape of the prototype model. A rear face space of the ultra-plastic material having the shape of the prototype model is filled with a filler 6 and unnecessary parts are eliminated. Thereafter, after-workings such as hole making, polishing, surface modifying are performed.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a mold used in a plastic injection molding machine.

[0002]

2. Description of the Related Art High-grade molds and long-life molds are made of steel (S55
With C material, NAK55 material, etc.), each mold part is machined, electric discharge machined (electrode machined), polished, heat treated, etc. to assemble, but the machining process is multiple and the delivery time is long,
Expensive. For simplicity, there is a mold that makes a prototype model, molds it with a resin containing metal powder, and adds some processing to assemble it, but its strength is weak (especially shear) and its life is short.

[0003]

The above-mentioned conventional steel mold has a problem that the number of processing steps is long, the delivery time is long and the cost is high, and the simple mold has insufficient strength. However, there is a problem that the life is short.

[0004]

In order to solve the above-mentioned problems, the method of the present invention produces an original model 1, preheats a superplastic material 2, and forms the original model 1 and the superplastic material 2 into a mold 4. After setting, the superplastic material 2 is deformed into the original model shape, the back space portion of the original superplastic material having the original model shape is filled with the filler 6, and unnecessary portions are removed, and then the hole machining, polishing, and surface modification are performed. It is characterized by post-processing such as quality.

[0005]

1 (A) to 1 (G) are explanatory views showing the constitution of one embodiment of the method of the present invention. In this embodiment, a prototype model 1 having a product shape as shown in FIG. 1 (A) is manufactured by machining, and a superplastic material 2 as a surface of a mold forming portion is heated as a heater as shown in FIG. 1 (B). 25 by 3
Preheat to 0-270 ° C. As shown in FIG. 1 (C), the original model 1 and the superplastic material 2 are set in a mold 4 and
As shown in (D), the air 5 is blown in to obtain a pressure of 1 to 10MP.
a is added for 2 to 10 minutes to deform the superplastic material 2 into the original model shape. Then, as shown in FIG. 1 (E), the filler 6 is placed in the space behind the superplastic material 2 having the original model shape.
1C is poured and cured, and as shown in FIG. 1 (F), unnecessary portions of the mold are removed by machining or the like.
As shown in (G), post processing such as hole processing, polishing processing, and surface modification is performed. Then, it is incorporated into the die set. The superplastic material exhibits an elongation of about 1500% and can be precision processed. FIG. 2 is an explanatory view of a plastic injection molding die using a superplastic material, 7 is a die of the present invention composed of a superplastic material 2 having an original model shape and a filler 6, and 8 is a molded product.

[0006]

As described above, according to the present invention, the cost can be reduced as compared with the steel mold. The life can be extended compared to a resin mold containing metal powder. It is a reproduction of the original model and there are no shape defects. Compared with steel molds, there are fewer machining processes, the polishing process can be greatly shortened, and the product model can be used as it is.

[Brief description of drawings]

1 (A) to 1 (G) are explanatory views showing the configuration of one embodiment of a method of the present invention.

FIG. 2 is an explanatory view of a plastic injection mold using a superplastic material.

[Explanation of symbols]

 1 original model 2 superplastic material 3 heater 4 mold 5 air 6 filler 7 mold of the present invention 8 molded product

Claims (2)

[Claims] 1. A method of manufacturing a plastic injection molding die, which is characterized by forming a die using a superplastic material by using an original model. 2. A prototype model is produced, the superplastic material is preheated, the prototype model and the superplastic material are set in a mold to deform the superplastic material into the prototype model shape, and the superplastic material having the prototype model shape. A method for manufacturing a plastic injection mold, which comprises filling a back space with a filler, removing unnecessary portions, and then performing post-processing such as hole processing, polishing processing, and surface modification.