JPS62196120A - Molding method - Google Patents

Abstract

PURPOSE:To obtain a high-quality molded item at good yield in manufacture by a method wherein a material to be molded is arranged between a mold and an elastic body, the position corresponding to the recess of the mold of which is constituting so as not to protrude beyond its peripheral part, and then pressure is applied to the elastic body. CONSTITUTION:An elastic body 3 is placed on a material to be molded 4, which is set on a mold 1. In the above-mentioned state, because the surface of the elastic body 3 is flat, the material to be molded 4 and the elastic body 3 come into uniform contact with each other regardless of the position at the recess 2 of the mold 1 and the remaining position excluding the position at the recess 2. Accordingly, after that, when a downward force is applied to the elastic body 3 by means of a pressing means, the force given by the pressing means acts nearly uniformly on the underside of the elastic body 3 at the start of the application of the force. Consequently, the material to be molded 4 is pressed at the periphery of the recess 2 by the top surface of the mold 1 and the elastic body 3. Thus, the material to be molded 4 is given deforming pressure by the elastic body 3. As a result, after the predetermined period of time, a projection corresponding to the recess 2 is formed on the material to be molded 4.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a molding method.

[Prior art and its problems]

For example, as a means for forming a convex part at a predetermined position of a plastic sheet, a plastic sheet 1~ is placed between a female mold having a concave part and a male mold having a convex part corresponding to the concave part, A pressing force is applied between the female mold and the male mold while heating if necessary. In other words, for membrane switches or Braille display boards for the blind, etc., not only are characters, symbols, etc. printed on the plastic sheet, but also protrusions may be provided on the plastic sheet to correspond to these characters or symbols. desired. In particular, for membrane switches, etc., it is strongly desired to provide the above-mentioned protrusions in order to concentrate the pressing force from the fingers on one point, and it is also essential for Braille display boards for the blind, etc. This is a requirement. However, in the conventional method of placing a plastic sheet between a female mold with a concave part and a male mold with a convex part, and forming a convex part at a predetermined position on the plastic sheet by press molding, the position of the convex part It has the disadvantage of poor delivery accuracy.

[Means to solve problems]

As a result of research into the above-mentioned problem, the inventor of the present invention found that the reason why the formation position of the convex part deviates somewhat from the predetermined position is that the tip of the convex part of the male die in which the convex part was formed is the object to be molded. We discovered that this is because when the plastic sheet comes into contact with the corresponding female recess, it begins to drag the plastic sheet.Based on this knowledge, we conducted further research. between a mold provided with a recess and an elastic body configured such that a position corresponding to the recess of the mold does not substantially protrude from its periphery;
The inventors have discovered that the above-mentioned problems can be solved by arranging the object to be molded and applying pressure to the elastic body to form the convex portion.

【Example】

1 and 2 are schematic illustrations of one embodiment of the molding method according to the present invention. In each figure, reference numeral 1 denotes a mold made of, for example, metal or other suitable hard material and provided with recesses 2 corresponding to positions where convex portions are to be formed on the object to be molded, which will be described later. Note that the upper surface around this recessed portion 2 is configured to be flat. Reference numeral 3 denotes an elastic flat plate made of an elastic material such as silicone rubber and having a thickness of about 5 mm, and is made flat at least at a peripheral position corresponding to the recess 2. 4 is a molded object such as a resin plate such as a plastic sheet or a metal plate such as aluminum foil. Note that characters, symbols, etc., are printed in advance on the surface of the molded article 4 by a predetermined printing means depending on the purpose of the molded article. In order to form a convex portion at a predetermined position on the object to be molded 4, first, as shown in FIG. Place 3. In this state, since the surface of the elastic body 3 is flat, the object to be molded 4 and the elastic body 3 are uniformly connected to each other regardless of the difference between the position of the recess 2 of the mold 1 and the position of other parts than the recess 2. are in contact. Therefore, if a predetermined press means (not shown) applies a force downward in the figure to the elastic body 3, the force from the press means will act almost uniformly on the lower surface of the elastic body 3 at the beginning of the force application. As a result, the object 4 to be molded is pressed against the upper surface of the mold 1 and the elastic body 3 around the recess 2, and the object 4 to be molded is firmly fixed in its position. Then, as the force from the pressing means increases on the elastic body 3, the elastic body 3 begins to deform at the corresponding position of the four parts 2, and as shown in FIG. regular,
In response, the object 4 receives deformation pressure from the elastic body 3, and after a predetermined period of time, a convex portion corresponding to the recess 2 is formed on the object 4. Although not specifically mentioned above, the object 4 may be heated as necessary during press molding. Further, in the above embodiment, the elastic body 3 is explained as a flat plate, but it may be something like a rubber roller. In other words, the mold 1 and the molded object 4 are polymerized between a plurality of rubber rollers. The molding may also be carried out by supplying the material. When the convex portion is formed as described above, the object to be molded 4 around the convex portion forming position is supported prior to forming the convex portion, so that the convex portion forming pressure is 1 or more when the convex portion is formed. The molded object 4 will not be misaligned even when used.
Therefore, the accuracy of the position of forming the convex portion is extremely high. For this reason, when manufacturing membrane switches or Braille display boards for the blind using this molding method, the position of the convex portions is extremely accurate, making it possible to provide high-quality products with a high manufacturing yield. Become. Furthermore, considering the process of forming a convex portion on the molded object 4, the force from the press means is transmitted to the molded object 4 via the elastic body 3, so the force is transmitted through the elasticity. The material deterioration of the molded object 4 around the convex formation position does not occur, and for example, the molded object 4 is torn or whitened around the convex formation position. It also becomes difficult.

【effect】

In the molding method according to the present invention, a molded object is placed between a mold provided with a concave portion and an elastic body configured such that positions corresponding to the four parts of the mold do not actually protrude from the surrounding area. However, since pressure is applied to the elastic body, the positional accuracy of forming the convex portions on the object to be molded is high, and since the pressure for forming the convex portions on the object to be formed is not applied abruptly, it is possible to It has the advantage of having little material deterioration and therefore being able to provide molded products of high quality and good manufacturing yield.

[Brief explanation of drawings]

FIGS. 1 and 2 are explanatory views showing one embodiment of the molding method according to the present invention. 1... Mold, 2... Concavity, 3... Elastic body, 4...
Object to be molded. Figure 1 Figure 2

Claims (1)

[Claims] A molded object is placed between a mold provided with a recess and an elastic body configured such that a position corresponding to the recess of the mold does not substantially protrude from the surrounding area, and pressure is applied to the elastic body. A molding method characterized by adding.