JPH033373Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to an extrusion die for inorganic products.

[Conventional technology]

Conventionally, extrusion molding of inorganic building materials made of fiber-reinforced cement and the like has been widely practiced.

In this extrusion molding, when giving the surface of the molded product a continuous uneven surface in the extrusion direction, a molding die D having a predetermined uneven cross-sectional shape is attached to the discharge port for extruding the cement slurry, as shown in FIG. Fifth
A molded product having a cross-sectional shape as shown in the figure is extruded.

[Problems with conventional technology]

However, when extruding a molded product with an irregular cross-sectional shape by the above-mentioned means, the molded product G immediately after being extruded from the molding die D has a so-called drum shape as shown in FIG. 6 due to the release of extrusion pressure. There was a problem in that the area (portion indicated by P in the figure) swelled and could not be formed into the desired shape.

[Problems solved by invention]

This invention was made in view of the above-mentioned problems, with the purpose of providing an extrusion molding die that does not undergo expansion deformation after extrusion.

[Technology to solve problems]

That is, in the extrusion molding die for inorganic products of this invention, a die having an uneven inner surface forming a cross section of the product is attached to the slurry discharge port, and the inner cross-sectional shape of the raw material flow path from the kneading extruder to the die is the same as that of the die. It is characterized by having a tapered diameter-reduced surface corresponding to the uneven surface, which gradually approximates the uneven inner surface shape of the uneven surface.

〔Example〕

Next, this invention will be explained using examples.

Figure 1 is a side sectional view of an embodiment of this invention;
The figure is a cross-sectional view taken along the - line in FIG. 1.

In the extrusion molding die 1 for inorganic products of this invention, a die 3 having uneven inner surfaces 3A and 3B forming a cross section of the product is attached to a discharge port 2 for extruding an inorganic kneaded material, for example, cement slurry, and a kneading extruder As shown in FIG. 2, the inner cross-sectional shape of the raw material flow path 5 from 4 to the mouthpiece 3 has uneven surfaces 3A, 3 that gradually approximate the shape of the uneven inner surfaces 3A, 3B of the mouthpiece 3.
The tapered diameter-reducing surfaces 5A and 5B corresponding to B are configured.

In addition, although the case of the base of a solid molded body was shown as the above-mentioned example, it can be carried out similarly in the case of a hollow molded body as shown in FIG. In addition, this embodiment has the same configuration as the previously described embodiments except that the hollow pins 6 . .

[Effect]

When an inorganic product is extruded using the inorganic product extrusion molding die 1 of this invention, the slurry S extruded from the extrusion screw 4A of the extruder gradually follows the uneven shape of the die 2 in the flow path 5 leading to the die 2. As the flow cross section changes, the pressure becomes uniform during this flow process.

Therefore, the slurry S that is finally extruded with its shape regulated by the nozzle 2 has a substantially uniform internal pressure, and does not swell or deform locally, and exactly follows the shape of the nozzle 2. It is considered a shape.

〔effect〕

As explained above, in this invention, the cross-section of the flow path of the raw material slurry leading to the forming die is gradually tapered to correspond to the shape of the discharge port as it approaches the forming die, so that there is no excessive lateral pressure on the extruded raw material. It has practical effects such as being able to mold a molded product without applying heat and making it easier to control the shape of the product.

[Brief explanation of drawings]

Figure 1 is a side sectional view of an embodiment of this invention;
1, FIG. 3 is a sectional view of another embodiment, and FIGS. 4, 5, and 6 are explanatory diagrams of a conventional example.

Claims (1)

[Scope of utility model registration request] A die having an uneven inner surface forming a product cross section is attached to the slurry discharge port, and the inner cross-sectional shape of the raw material flow path from the kneading extruder to the die is gradually approximated to the uneven inner surface shape of the die. An extrusion molding die for inorganic products characterized by having a corresponding tapered diameter reducing surface.