JPS6016889B2 - Molding device for molded bodies with uneven cross sections - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a molding apparatus for molding a molded article having an uneven cross section, such as a roof tile.

Traditionally, hydraulic compositions such as cement have been molded using cast molding methods, in which a material mixed with water is injected into a predetermined mold and hardened, and press molding methods, in which the material is compression molded in a predetermined mold. However, all of these methods have the disadvantage of being inefficient because they are intermittent molding methods.

Furthermore, since a considerable amount of water is used, the alkali in the cement often dissolves and causes white spots on the surface of the resulting product, a so-called efflorescence phenomenon. In order to overcome these drawbacks, the material is extruded from a molding die using a screw or the like. A so-called extrusion molding method was developed, but with this method only a molded product with unevenness can be obtained in the cross section perpendicular to the extrusion direction, and in the case of a wide molded product, distortion is likely to occur due to uneven pressure. There was a drawback. This invention improves these shortcomings of the conventional molding method, makes it possible to efficiently mold a molded product that is less prone to distortion even when the uneven cross section is wider, and also makes it possible to efficiently mold a molded product that is less prone to distortion.
It is an object of the present invention to provide an apparatus capable of molding a molded body having a shape in which irregularities also appear on one of the surfaces in a cross section along the direction of movement of the lower die. This will be explained below. The apparatus for molding a molded article having an uneven cross section according to the present invention includes a lower mold that has a molding surface corresponding to the lower surface shape of the molded object and is moved by a conveyor, and a cross section that is located above the lower mold and that is perpendicular to the direction of movement of the lower mold. A forming roll having a processed surface with a shape corresponding to the upper surface shape of the formed article, located in front of the forming roll, with a lower end having a shape similar to the lower end shape of the forming roll, and above the lower end of the forming roll. It is characterized by consisting of a leveling plate located at the top and a material feeding impeller disposed in front of the leveling plate.

To explain this based on an example, Fig. 1 is a configuration diagram of this molding apparatus. In this figure, a bottom surface (forming A plurality of lower molds 2 each having a surface) are placed thereon. In this case, the bottom surface shape of the lower die may be such that unevenness appears along the direction of movement. A forming roll 3 rotating in the direction of arrow B is provided above the lower die. The forming roll 3 has a processed surface (outer circumferential surface) having a shape corresponding to the top surface shape of the molded article in a cross section perpendicular to the direction of movement of the lower die. Immediately before the forming roll, a leveling plate 4 is provided to level the upper surface of the molding material 7 fed into the forming roll. The lower end of this leveling plate 4 has a shape similar to that of the lower end of the forming roll, and is located above the lower end of the forming roll. Leveling board 4
In front of the is a material feeding impeller 5 rotating in the direction of arrow C.
is installed. The impeller 5 is made up of a plurality of vanes placed around a rotating shaft, and is disposed only in areas where the material fed into the forming rolls is likely to be interrupted. In such a configuration, the molding material 7 such as a cement-based kneaded material supplied onto the lower mold in front of the leveling plate advances in the direction of arrow A as the conveyor moves, and the upper surface is flattened by the leveling plate 4. After being smoothed into the shape of the processed surface of the forming roll, it is fed into the forming roll 3, and is pressure-formed into the desired molded body between the forming roll and the lower die. In this case impeller 5
serves to prevent the molding material fed into the molding rolls from being interrupted. Next, a case in which a molded body having a cross section as shown in FIG. 2 is molded will be explained in more detail by way of example.
The forming roll used in this case has a shape as shown in FIG. FIG. 3 is a front view, and an uneven shape corresponding to the upper surface shape of the molded article shown in FIG. 2 appears at the lower end of the processed surface of the forming roll. FIG. 4 shows the relationship between the forming roll 3, the lower die 2, and the leveling plate 4. In other words, the space formed by the forming roll 3 and the lower die 2 forms the cross-sectional shape of the formed body, and the lower end of the leveling plate 4 becomes a convex part relative to the convex part of the forming roll, and the space formed by the forming roll 3 forms a convex part relative to the concave part of the forming roll. There is a recess. With this leveling plate, the molding material on the lower die is leveled to approximately the shape of the processed surface of the forming roll.
By shaping the molding material in advance into a shape that approximately conforms to the shape of the machined surface of the forming roll, a molded body with a uniform density distribution and less distortion can be obtained. The difference between the lower end of the leveling plate and the lower end of the forming roll is a compression margin for pressure forming. In this case, the difference t between the lower end of the forming roll at the concave portion of the forming roll and the lower end of the leveling plate is larger than the difference between the convex portions of the forming roll. This is because the outer diameter of the convex part of the forming roll is large, so the circumferential speed is high, and it is easier to roll in more molding material than the concave part, which has a small circumferential speed. This is to keep it to a minimum. If the amount of the molding material involved differs locally, there is a risk that the resulting molded product will be distorted. FIG. 5 shows the external appearance of the leveling board used. If the distance between the leveling plate and the forming roll is too large, the material tends to break off between them, so it is better to make this distance as small as possible. Also, for the same reason, it is not preferable to make the thickness of the leveling board too large. Normally, it is appropriate to set this thickness to 3 skins or less. FIG. 6 is an external view of the impeller 5, which is made up of a plurality of plates 52 placed around a rotating shaft 51 that is forcibly rotated. The number of blades to be used as blades should be selected appropriately depending on the properties of the molding material, the number of rotations and the molding speed. Figure 7 shows the positional relationship with respect to the forming rolls when this impeller is installed. As you can see from this figure, the impeller is placed on the convex part of the forming roll where the leveling plate reduces the amount of forming material compared to the other parts.The purpose of providing the impeller is as described above. The goal is to ensure that the molding material is not completely added to the roll. In the case shown in the figure, the amount of molding material is reduced by the leveling plate. Discontinuation of the molding material occurs at the center (convex part) of the roll. Therefore, an impeller is placed in this area to forcibly feed the molding material.The distance between the impeller and the leveling plate can be selected appropriately depending on the properties of the molding material, molding speed, etc. Due to the function of the leveling plate and the impeller, it is possible to mold a molded product with a complex uneven shape with a uniform density distribution.
A forming die is provided as necessary to make the surface of the obtained molded product smoother and to prevent the molded product from lifting off from the lower die.

This forming die 6 has a processing surface corresponding to the upper surface shape of the molded object, and the forming surface is usually 1'1000 to 20 mm.
The outlet side is narrower than the inlet with a gradient of /I00, and if this is provided immediately after the forming roll (preferably in contact with the forming roll), the surface of the formed product will be finished extremely smooth, and Unnecessary deformation and damage can be prevented by holding down the uncured molded product, which tends to separate from the lower mold and float up. FIG. 8 is an external view of the forming die seen from the inlet side. Reference numeral 8 in FIG. 1 is the obtained molded product, which is later cut into a predetermined size and taken out from the lower mold.
As can be seen from the above structure, this molding method is extremely efficient as it is a continuous molding method, and even when using a molding material made by kneading a cementitious composition with water, it does not require much fluidity, so water can be appropriately reduced, so that the white fist phenomenon is less likely to occur in the molded article. Also,
The surface formed by the lower die may have unevenness along the direction of movement. As explained above, the apparatus for molding a molded article having an uneven cross section according to the present invention has a molding surface corresponding to the lower surface shape of the molded article and is located above the lower mold, which is moved by a conveyor, and is positioned above the lower mold as the lower mold advances. A forming roll having a processed surface having a shape corresponding to the upper surface shape of the formed object in a cross section perpendicular to the direction, the forming roll being located in front of the forming roll, and having a lower end having a shape similar to the lower end shape of the forming roll. The feature is that it consists of a leveling plate located above the lower end and a material feeding impeller placed in front of the leveling plate, so even if it is a wide molded product with an uneven cross section, it will not be distorted. It is now possible to efficiently mold a molded product that is difficult to form, and it is also possible to form a molded product with a shape that has unevenness on either the front or back surface in the cross section along the direction of movement of the lower mold. can also be molded).

[Brief explanation of the drawing]

Figure 1 is a configuration diagram of the molding device, Figure 2 is a sectional view of the molded body,
Figure 3 is a front sectional view of the forming roll, Figure 4 is an explanatory diagram of the positional relationship of the forming roll, lower die, and leveling plate, Figure 5 is an external view of the leveling plate, and Figure 6 is the external appearance of the impeller. FIG. 7 is an explanatory diagram of the positional relationship of the impeller, and FIG. 8 is an external view of the forming die. All figures represent examples. 1... Conveyor, 2... Lower die, 3... Forming roll,
4... leveling board, 5... impeller, 6...
...Forming die. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] 1. A lower mold that is moved by a conveyor and has a molding surface that corresponds to the shape of the lower surface of the molded object, and that is located above the lower mold and corresponds to the shape of the upper surface of the molded object in a cross section perpendicular to the direction of movement of the lower mold. a forming roll having a processing surface shaped like this, a leveling plate located in front of the forming roll, the lower end of which has a shape similar to the lower end shape of the forming roll, and which is above the lower end of the forming roll; A device for forming a molded body with an uneven cross section, consisting of an impeller for feeding material placed in front of a leveling plate. 2. An apparatus for forming a molded body having an uneven cross section according to claim 1, characterized in that a forming die having a processing surface corresponding to the upper surface shape of the molded body is disposed behind the forming roll. .