JPH0235138Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a key top molded from two-color resin materials.

[Prior art]

Generally, the bottom of the key top comes into contact with the switching element, so it needs to be machined with high precision.

Conventionally, this type of keytop has been the first choice because it is more durable and decorative than those with numbers displayed by hot stamping or printing.
As shown in the figure, a molded product consisting of a primary molded product 1 and a secondary molded product 2 is widely used.

However, even if the primary molded product 1 is formed into a block shape immediately after the primary molding, the entire product will move toward the center of the primary molded product 1 (in the direction of the arrow) after solidification, as shown in Figure 2. Since the molding is performed by shrinking (the shrinkage rate is small), during secondary molding, the secondary molding resin 3 is mixed with the contracted part of the primary molded product 1, that is, the primary molded product 1 and the mold as shown in FIG. 4, so-called fogs 6 are formed on the bottom surfaces of the primary and secondary molded products 1 and 2, as shown in FIG.
For this reason, the prior art has the disadvantage that additional processing must be performed after secondary molding.

[Summary of the idea]

The present invention was developed in view of these circumstances, and has an extremely simple structure in which a thin-walled flange is provided at the end of the primary molded product body on the side opposite to the protrusion.
This provides a key top that does not require additional processing after secondary molding. Hereinafter, the configuration and the like will be explained in detail by referring to embodiments shown in the drawings.

〔Example〕

FIG. 5 is a sectional view showing the key top according to the present invention. In the same figure, what is indicated by numeral 11 is 2
This key top is molded from a colored synthetic resin material, and includes a block-shaped primary molded product 14 having a protrusion 13 forming a display section on the upper surface 12, and a main molded product body 15 on the side opposite to the protrusion. The primary molded product 1 is shaped so that the end portion and the upper surface 12 of the protruding portion 13 are exposed.
4, and a secondary molded product 16 that covers 4.
Reference numeral 17 denotes a thin-walled collar that contacts the bottom surface 18 of the secondary molded product 16, and is integrally provided at the end of the primary molded product main body 15 on the side opposite to the protruding part, thereby preventing the secondary molded resin from being exposed. Infiltration to the bottom side of the primary molded product 14 is prevented.

In the key top 11 configured in this way, as shown in FIG.
Even if the primary molded product body 15 inside shrinks and a gap 21 is formed between the primary molded product body 15 and the mold 20,
Since the collar 17 is thin, it hardly contracts. Therefore, since the collar 17 and the mold 20 are in close contact with each other, the secondary molding resin fills the gap 21 during secondary molding.
There will be no inflow into the country.

[Effect of idea]

As explained above, according to the present invention, a thin-walled flange is provided at the end of the primary molded product body on the side opposite to the protrusion, so that it contacts the bottom surface of the secondary molded product. Fogging caused by resin entering between the primary molded product and the mold is eliminated. Therefore, it is possible to obtain a key top that does not require additional processing after secondary molding.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a conventional key top;
The figure is a cross-sectional view showing the primary molded product, Figure 3 is a cross-sectional view to explain the key top during molding, Figure 4 is a cross-sectional view showing the conventional key top, and Figure 5 is the key top according to the present invention. FIG. 6 is a cross-sectional view showing the molded state of the key top. 11...Key top, 12...Top surface, 13...
Projection, 14... Primary molded product, 15... Primary molded product body, 16... Secondary molded product, 17... Tsuba, 18
...Bottom surface.

Claims (1)

[Scope of utility model registration request] A block-shaped primary molded product having a protrusion forming a display portion on the upper surface, and a primary molded product such that the end of the main body of the primary molded product on the side opposite to the protrusion and the upper surface of the protrusion are exposed. It consists of a secondary molded product that covers the
At the end of the primary molded product body on the side opposite to the protrusion,
A key top characterized by having a thin-walled flange that is in contact with the bottom of the next molded product.