JP2630168B2 - Extrusion molding method of tile - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for extruding a tile, and more particularly, to a method for easily and surely producing a warp-free tile by extrusion.

[0002]

2. Description of the Related Art As one of the methods for forming ceramic tiles,
There is an extrusion molding method in which a kneaded material is extruded by a wet method.
In the case of the extrusion molding method, usually, the kneaded material is extruded into a long molded body, cut into a predetermined size, and then dried, fired, and the like to form a product tile.

[0003] In the extrusion molding of tiles and the like, although no warpage is observed at the stage immediately after extrusion molding,
In many cases, the molded product (tile) warps in the process of drying and firing. This is due to the density of the material in the molded body immediately after extrusion, and as a result, the degree of shrinkage when the molded body shrinks through the drying and firing steps becomes uneven between the high density part and the low density part, which warps the tile. It is thought to be the cause of this.

[0004] By the way, the reason why the density of the material is varied during the extrusion molding is that the extruded material, that is, the kneaded material is not uniform at each part when the extruded material passes through the forming die at the tip of the extruder. Despite the substantial difference in extrusion speed, the extruded product is extruded as an integral long product, that is, the side with the higher extrusion speed pulls the side with the lower extrusion speed to assist the extrusion. Can be

For example, as shown in FIG. 2 (A), when the extrusion speed at the left end of the molded body 100 is high and the extrusion speed at the right end is low, the extrusion speed immediately after extrusion depends on the difference in extrusion speed. The molded body 100 tends to deform, but after being extruded to a certain length as shown in FIG. 2 (B), deformation resistance based on the guide of rollers, belts and the like is added, and the molded body 100 is deformed. It cannot be easily deformed by warping.In this case, the side with the higher extrusion speed on the left end works to pull out the side with the lower extrusion speed on the right end. Both the left and right edges are extruded at the same speed. As a result, as shown in FIG.
This is considered to be a cause of warpage after firing.

The above is an example of side warpage (see FIG. 3A). If there is a substantial difference in the extrusion speed between the upper side and the lower side of the molded body 100, FIG. In the case where the surface warpage as shown in FIG. 3A occurs and there is a substantial difference in the extrusion speed between the left and right end portions and the central portion, the cut surface warpage as shown in FIG. A deformation occurs such that the central portion in the width direction of the portion bulges or dents in the extrusion direction.

Therefore, in order to prevent such a warp, the extruded molded body is conventionally taken out of a forming line, and after drying, signs of the warp are determined, and the warp is eliminated according to the presence or absence and the direction of the sign. As described above, by controlling the flow resistance (extrusion resistance) of the kneaded material inside the die at the end of the extruder, a surface perpendicular to the extrusion direction of the extrusion port (hereinafter sometimes referred to as an extrusion cross section).
The extrusion speed in the inside is adjusted so as to prevent the compact from becoming dense and compact.

[0008] Conventionally, drying of the tile molded body extracted from the molding line has been performed by a hot air dryer.

[0009]

However, in drying with a hot air drier, unevenness in drying is likely to occur due to the condition of the hot air, and there is a possibility that warpage due to the unevenness in drying may occur. There is a disadvantage that the warpage caused by the above cannot be obtained accurately. In addition, insufficient reproducibility of the dry state has also been a cause of inaccurate determination of warpage.

[0010] Moreover, in the drying with a hot air dryer, it takes 3 to 4 hours to dry. Therefore, it takes a long time to determine the warpage of the tile molded body extracted from the forming line, and it is necessary to eliminate the warpage. Immediately adjust the extrusion speed of
There is also a disadvantage that it cannot be dealt with promptly.

The present invention solves the above-mentioned conventional problems, and extracts a tile molded product from a molding line for extruding a kneaded material from a die extrusion port at the tip of an extruder to obtain a tile molded product, and drying and extracting the tile molded product. Measure the warp, and in order to eliminate this warp, in a method of extruding a tile in which the extrusion speed distribution of the kneaded material from the extrusion port in a plane perpendicular to the extrusion direction was adjusted, the tile was extracted from the molding line. It is an object of the present invention to provide a method for drying a tile formed body uniformly and quickly, with good reproducibility, and for reliably preventing warpage due to an imbalance in extrusion speed.

[0012]

According to the method for extruding a tile of the present invention, a kneaded material is extruded from an extrusion opening of a die at the tip of an extruder, and then cut into a predetermined length to form a tile molded product. Extruding a tile formed body from a molding line, drying and measuring warpage, and kneading from the extrusion port in a plane orthogonal to the extrusion direction so as to eliminate the warpage. In a method of extruding a tile in which the extrusion speed distribution of a product is adjusted, the tile molded body extracted from the molding line is dried by a vacuum dryer, and the warpage is measured.

[0013]

According to the vacuum dryer, uniform drying can be performed quickly and with good reproducibility. Incidentally, while the conventional hot air dryer required 3 to 4 hours to dry the tile molded body, the vacuum dryer according to the present invention can be dried in a short time of 1 to 1.5 hours. .

Accordingly, the time lag from the measurement of drying and warpage of the tile molded body extracted from the forming line to the adjustment of the extrusion speed distribution for eliminating warpage is reduced.
It is possible to prevent warpage due to uneven drying and accurately measure warpage due to imbalance in extrusion speed.Adjust the optimum extrusion speed distribution to obtain good product tiles without warpage at high yield. It is possible to obtain.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The method for extruding a tile according to the present invention will be described in detail below.

In the method for extruding a tile according to the present invention, the kneaded material is extruded from an extrusion opening of a die at the tip of the extrusion, and then cut into a predetermined length to form a tile molded body. The molded body was extracted, dried and measured for warpage, and in order to eliminate the warpage, in adjusting the extrusion speed distribution of the kneaded product from the extrusion port in a plane perpendicular to the extrusion direction, the molded body was extracted from the molding line. Drying of the tile compact is performed by a vacuum dryer.

There are no particular restrictions on the drying conditions of this vacuum dryer, and they are appropriately determined according to the size, thickness, etc., of the extracted tile molded body.

If no warpage is detected by measuring the warpage after drying, it is not necessary to adjust the extrusion speed.
If warpage is detected, the extrusion speed distribution is adjusted so as to eliminate the warpage.

Hereinafter, a method of adjusting the extrusion speed will be described. As a mechanism for giving extrusion resistance to a material, there is a mechanism described in Japanese Patent Application No. 1-287701 (see Japanese Patent Application Laid-Open No. 3-147806, particularly FIG. 3). This mechanism will be described with reference to FIG.

The forming die 12 is provided with an extrusion port 14 for a product.
And an extruding port 16 for separating discarded portions (ears) at both ends separated by a partition plate, so that the extruded product is extruded and the ears at both ends are separated at the same time.
It should be noted that two pairs of resistors 18 and 20 are provided on the inner side (rear side) of the extruder of the forming die 12 so as to be able to advance and retreat in the direction of approaching / separating (approaching / separating) from the extrusion ports 14 and 16. I have. These resistors 18 and 20 are moved forward and backward by bolts 22 and 24. That is, the resistors 18 and 20 are fixed to the tips of the support shafts 26 and 28, and the rear ends of the support shafts 26 and 28 extend to the outside of the forming die 12, and the connecting plate 30 is attached to the rear end. , 32 are fixed. The bolts 22,
The connection plates 30, 32, the support shafts 26, 28, and the resistors 18, 20 are advanced and retracted by screwing the bolts 22, 24.

The resistors 18 and 20 are composed of main pieces 18a and 20a along the back surface of the forming die 12 and a main piece 18a.
a and 20a are provided with upstanding pieces 18b and 20b that rise from the tip sides of the extrusion ports 14 and 16 to the inside of the extruder. The upright pieces 18b and 20b are arc-shaped plate-like ones as shown in FIG.

As shown in FIG. 1, the extrusion port 14 has a flat rectangular shape in the extrusion section, and the resistor 20 extends along two long sides in the extrusion section direction of the extrusion port 14. Are arranged one by one.

In such an extruder, the resistor 1
Operate 8,18,20,20 to adjust the extrusion speed. That is, specifically, the resistor 18 with the lower extrusion speed is pulled in from the current position, or the resistor 18 with the faster extrusion speed is extruded deeper than the current position. To be. By doing so, the substantial extrusion speed of both sides of the tile molded body becomes uniform, so that even if the molded body is subsequently dried and fired, no side warpage occurs. In addition, the resistance 2
The extrusion speed of the molded body is adjusted to an appropriate speed by pushing 0, 20 deeper or by pulling in the resistor 18 on both the left and right sides. Thereby, it is also possible to prevent the cut surface warpage due to the density of the materials at the center and both sides of the product tile.

The adjustment of the extrusion speed distribution is not limited to the adjustment of the positions of the resistors 18 and 20 shown in FIG. 1, and other methods can be adopted according to the mode of the extruder. Needless to say.

[0025]

As described above in detail, according to the method for extruding a tile of the present invention, the kneaded material is extruded from the extrusion port of the die at the tip of the extruder, and then cut into a predetermined length. A method of extruding a tile to be a tile molded body, wherein the tile molded body is extracted from a molding line, dried and measured for warpage, and the pressing in a plane perpendicular to the extrusion direction is performed so as to eliminate the warpage. In the method of extruding a tile in which the extrusion speed distribution of the kneaded material from the outlet is adjusted, it is possible to accurately and quickly measure the warpage due to the imbalance in the extrusion speed distribution, and to adjust the optimum extrusion speed distribution. To obtain a good product tile without warpage at a high yield.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an extrusion molding machine.

FIG. 2 is an explanatory diagram showing an extruded state.

FIG. 3 is an explanatory diagram showing warpage of a molded body.

[Explanation of symbols]

 Reference Signs List 12 forming die 18, 20 resistor 18a, 20a main piece 18b, 20b upstanding piece 22, 24 bolt 100 formed body

Continuation of the front page (56) References JP-A-3-147806 (JP, A) JP-A-62-113512 (JP, A) JP-A-49-36708 (JP, A)

Claims (1)

(57) [Claims] 1. A method for extruding a kneaded material from an extrusion opening of a die at an end of an extruder, and then cutting the kneaded material into a predetermined length to form a tile molded body, comprising: Is extruded from the molding line and dried to measure the warp, and in order to eliminate the warp, extrusion of a tile in which the extrusion speed distribution of the kneaded material from the extrusion port is adjusted in a plane orthogonal to the extrusion direction. In the forming method, a tile formed body extracted from the forming line is dried by a vacuum drier, and the warpage is measured.