JPS6334777Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement in a molding device such as a surface plate and a model used in the molding of a vacuum mold.

Conventionally, the structure of the surface plate or model used for the production of vacuum molds is as shown in Fig. 1 or Figs. 3 and 4.
b', 1c') are formed into a so-called decompression box with a large decompression space A' that communicates throughout and the necessary reinforcing ribs 2 erected, and the decompression space A' and the model mounting surface. B or the model surface C, ventilation holes 3 are normally opened in an appropriate distribution, and the model 4 or model forming plate 5 placed on the support stand (1a' or 1b', 1c') When applying the film 6, the entire area of the decompression space A' inside the support is brought to negative pressure via the pressure reduction pipe 7' connected to the support (1a' or 1b', 1c') from the decompression device. The pressure is reduced and the film 6 is brought into close contact with the model mounting surface B or the model forming plate 5 by suction from the vent holes 3.

However, when using such a conventional molding method using a vacuum box, it is necessary to uniformly reduce the pressure in the entire large vacuum space A' inside the support base (1a' or 1b', 1c'). This not only requires large equipment for the decompression device, but also a strong negative pressure of up to 1 kg/cm ² acts on the inner surface of the support, so when depressurizing, the support must be configured as shown in the broken line in Figure 2. A problem arises in that the frame body is bent and deformed.
In order to deal with this problem, it is possible to strengthen the structure of the support base by reinforcing the reinforcing ribs 2, but on the other hand, in this case, the manufacturing cost increases,
This also brings about the problem of lack of ease of handling.

In addition, in the case of the above-mentioned molding method using a vacuum box, the volume of the vacuum space A′ is quite large, so it takes time to reduce the pressure to the required negative pressure level, and for this reason, a pressure reduction device is required. In addition to consuming extra power, the heated film tends to lose its plasticity due to a drop in temperature, and especially when the model has a complex shape, the surface film does not adhere completely and there is a large risk of mold defects. It was done.

The present invention was developed in view of these problems, and its purpose is to improve the structure of model supports used for surface plates, models, etc., and to reduce the pressure reduction space with a small amount of space. This is intended to prevent bending and deformation of this type of molding apparatus and shorten the depressurization time.

Hereinafter, the vacuum mold making apparatus according to the present invention will be described with reference to the illustrated embodiments. First, FIGS. 5 and 6 show an example of a surface plate shown in comparison with the conventional structure shown in FIGS. 1 and 2. Here, 1a is a model support base according to the present invention, 2 is a reinforcing rib thereof, 8 is a model mounting plate with ventilation holes 3 appropriately distributed and placed on the support base 1a, and 4 is a model mounting plate 8 that is placed on the support base 1a. The model is placed as the mounting surface B, and 6 indicates a film that is applied to the model. Therefore, in the case of the present design plate, a mesh body 9, such as a plain weave material, is interposed between the support base 1a and the model mounting plate 8 as a support member having air permeability.
This mesh body 9 forms a decompression space A between the two, and a decompression pipe 7 connected to a decompression device (not shown) is directly connected to the decompression space A by opening on the upper surface of the support base 1a. . That is, in the case of the present planning board, the support base 1a is not formed into a decompression box, but an appropriate support member having air permeability is used between the support base 1a and the model mounting plate 8 placed thereon. A depressurizing pipe 7 is inserted directly into the space created by this support member to form a necessary depressurizing space A in this portion.

Next, FIGS. 7 and 8 show examples of convex or concave models in contrast to the conventional structures shown in FIGS. 3 and 4. Here, 1b and 1c are model support stands according to the present invention, 2 is a reinforcing rib thereof, and 5 is a model forming plate (5) having ventilation holes 3 appropriately distributed as in the conventional example and placed on the support stands 1b and 1c. The film stretched over the surface C is not shown. However, in the case of the proposed model, a support member such as a breathable net 9 is interposed between the support stands 1b, 1c and each model forming plate 5, as in the case of the surface plate. A decompression space A is formed between the two by this support member, and the decompression pipe 7 is directly communicated with the support tables 1b and 1c.
support stands 1b, 1c without forming them into a decompression box.
A necessary depressurized space A is formed between the model forming plate 5 and each model forming plate 5.

As mentioned above, the model support stand (1a or 1
b, 1c) and the model mounting plate 8 placed thereon.
Alternatively, in a molding apparatus configured by interposing a support member between the model forming plate 5 to form a decompression space A, and having a decompression pipe 7 directly connected to the decompression space A, a large Decompression space
There is no need to provide A′ and form the entire support base into a decompression box, which eliminates the problem of deflection and deformation due to negative pressure applied inside the support base, and at the same time, the structure of the support base can be simplified and reduced in weight. . In addition, since the decompression space A requires only a small space due to the support member, the decompression time can be shortened (for example, from 5 seconds to 3 seconds), thereby ensuring the usable life of the heated film. Film tensioning can be completed,
The risk of mold defects is also eliminated. and,
Especially in the case of a surface plate, when the model 4 is changed, the mounting plate 8 is also replaced, and the ventilation holes 3 are changed according to the model 4.
It is sufficient to use the one that has been established, which has the advantage of being convenient for responding to changes in Model 4.

As described above, the proposed device has a simple structure, excellent durability and decompression performance as a vacuum mold making device, is inexpensive to manufacture, and is highly practical as it is convenient for handling such as attaching and detaching the model. In particular, if used in molding operations for high-mix, low-volume production, it will greatly contribute to improving productivity and reducing costs.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing the structure of a conventional decompression surface plate.
FIG. 2 is an enlarged view of the main part thereof, and FIGS. 3 and 4 are sectional views showing the structure of a conventional decompression box for a convex or concave model. Fig. 5 is a sectional view showing the structure of the decompression surface plate according to the present invention, Fig. 6 is an enlarged view of the main parts thereof, and Figs. 7 and 8 are the structures of the convex or concave decompression model according to the present invention. FIG. 1a, 1b, 1c...Model support stand, 2...Reinforcement rib, 3...Vent hole, 4...Model, 5...Model forming plate, 6...Film, 7...Reducing pressure tube, 8...Model Mounting plate, 9... Support member, A... Decompression space, B
...Model mounting surface, C...Model surface.

Claims (1)

[Scope of utility model registration request] A net is interposed between the model support stand and the model mounting plate or model forming plate placed thereon to form a decompression space, and a decompression pipe is directly connected to the decompression space. Features of vacuum mold manufacturing equipment.