JPH0216206B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for molding a model, particularly an elastic model with a complicated shape.

Usually, the above-mentioned model is molded by the following procedure. That is, a material (hereinafter referred to as mold material) to be used as a model mold (hereinafter simply referred to as a mold) is injected into a space formed by a mold and a model mold (hereinafter simply referred to as the master), and A mold is first obtained by curing the mold material. Thereafter, the mold is removed from the mold and the master mold located within the mold is removed. The material that will become the model (hereinafter referred to as model material) is injected into the space of the mold that has become a single member, that is, the part where the original was located, and the model material is cured to obtain the model. be. Note that the material to be the prototype will also be simply referred to as the prototype material hereinafter.

By the way, in conventional molding methods, materials that are liquid or plastic before hardening and exhibit elasticity after hardening are used as the master material, the mold material, and the model material. In other words, any material can be used as the original material and model material as long as it satisfies the above conditions. However, the type of material was changed for each material within the range of the above conditions.

However, this has caused various problems as described below. In other words, for the model,
Although an elastic model material is very advantageous, for the mold, on the other hand, the fact that the mold material is an elastic material leads to disadvantages. Specifically, since it is an elastic material, it is easily deformed, making it difficult to ensure the dimensional accuracy of the model, and furthermore, it is impossible to modify the model to change the design in the event of wear or chipping.

An object of the present invention is to solve the above-mentioned mold-related problems and obtain a highly accurate elastic model by providing a method for molding an elastic model with good workability.

The molding method of the present invention involves injecting a mold material that becomes relatively rigid with respect to the master mold after hardening into a space formed by a mold and a master mold fixed in the mold frame. After the mold material is hardened and the master mold is taken out to obtain a mold, a mold material that becomes elastic relative to the mold after hardening is injected into the space of the mold, and the mold material is hardened. It is characterized by allowing

That is, instead of using an elastic material as the mold material and the model material, the mold material used is a material that exhibits rigidity in the resulting mold, that is, a rigid material.

In this case, the rigid material may include various thermosetting resins, such as polyester resins, phenolic resins, melamine resins, silicone resins, epoxy resins, furan resins, alkyd resins, or urethane resins, or certain thermoplastic resins, For example, polyethylene resins, polystyrene resins or polyamide resins are used. These resins can be used alone or with various additives by conventional compounding techniques.

Note that the master material, mold material, and model material must exhibit the above-mentioned different characteristics after curing, but since they are in a liquid or plastic state before curing, no conditions are attached to them.

Embodiments of the present invention will be described below with reference to the drawings.

Figures 1 to 4 are supercharger impellers (products)
This figure shows the procedure for molding a model of the same shape as the figure, and the same reference numerals are given in the figure.

FIG. 1 shows the state when the mold material is injected. In this case, a predetermined shape (approximately the same as the model) obtained from the original mold material, for example, liquid rubber, is placed in the mold frame 1 of the bottomed cylinder. A mold material 4a, such as an adultite epoxy resin, is injected into the space 3 formed by the mold frame 1 and the mold shape 2 as shown in the figure, and the space is finally filled. 3 is filled with mold material 4a. Note that 2A indicates a part of the prototype 2, that is, a wing, but hatches are omitted for the sake of clarity. FIG. 2 shows a mold 4 obtained by curing the mold material 4a.
has been taken out from the formwork 1, and the master form 2 has also been removed. In other words, a mold 4 having a space 5 (a portion where the original mold was located) into which the model material is to be injected is obtained. Note that the dotted line portion indicates the groove 5A corresponding to the wing portion 2A. Figure 3 shows the above type 4
This figure shows the state after a model material 6a, for example, silicone rubber, has been injected into the space 5. Note that the dotted line portion indicates a wing portion 6A of the model corresponding to the wing portion 2A described above. Figure 4 shows the model 6 after hardening.
FIG. 4 is a state diagram when the model 6 is taken out from the mold 4, that is, a completed diagram of the model 6. In the figure, the curved thin object is the wing portion 6A.

In this way, in the example molding method for a supercharger blade wheel model, an elastic material, specifically liquid rubber, is used as the prototype material, a rigid material, specifically Arartite epoxy resin, is used as the mold material, and the model material is Since an elastic material, specifically silicone rubber, was used as the material, the above-mentioned model with a complicated shape could be obtained without using a mold release agent.

In this case, the molding time of the model can be further shortened by selecting various combinations of the original material and the mold material, or the combination of the mold material and the model material.

As described above, according to the model molding method of the present invention, since a rigid material is used as the mold material,
The problems mentioned above, such as easy deformation and difficulty in modification, are eliminated. In addition, since the mold material and the master material or model material are made of different materials, that is, the former is made of a rigid material and the latter is made of an elastic material, they do not separate from each other at each stage of molding. Very good. Furthermore, since there is no need to use a mold release agent, workability is improved and the uniformity of the surfaces of the master mold and mold can be maintained. This (no need to use a mold release agent), coupled with the fact that the mold material is a rigid material, leads to an improvement in the smoothness of the model surface, so the dimensional accuracy of the resulting model is extremely high. Become something.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention.
The figure is a cross-sectional view showing the state during injection of mold material, Fig. 2 is a cross-sectional view of the mold, Fig. 3 is a cross-sectional view showing the state after injection of model material, and Fig. 4 is a perspective view of the model. . 1... Formwork, 2... Prototype, 2A... Wing section, 3...
...Space, 4...Mold, 4a...Mold material, 5...Space, 5A...Groove, 6...Model, 6a...Model material.

Claims (1)

[Claims] 1. Injecting a mold material that becomes relatively rigid with respect to the mold after hardening into the space formed by the mold and the mold fixed in the mold, and curing the mold material. A model characterized in that, after the master model is taken out to obtain a mold, a model material that becomes elastic relative to the mold after hardening is injected into the space of the mold, and the model material is hardened. molding method.