JP2001047417A - Manufacture of flat plate tile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To moderate the difference in density between raw materials near an interface between the tile body part of a molding blank and its underlap part, without generating a significant variation of orientation in clay particles and inhibit a distortion or fissures generated near the interface between the tile body part and the underlap part during drying or baking. SOLUTION: This flat plate tile is manufactured by extrusion-molding a clay raw material into a platelike extrusion molding 10, then pressure-molding the platelike extrusion molding 10 into a molding blank 30 and forming a connected part between the tile body part 32 of the molding blank 30 and its underlap part 34 through pressure-molding the extrusion molding 10. The connected part 36 is inclined 30-60 deg. from the underlap part 34 to the tile body part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing flat tiles, and more particularly to a method for manufacturing flat tiles which suppresses distortion and cracks which tend to occur during drying and firing.

[0002]

2. Description of the Related Art Among clay tiles, flat tiles (F-type clay, Japanese Industrial Standard 5208A) have been increasing in demand in recent years with the spread of Western style houses. For example, as shown in FIG. 7, a general flat roof tile H has a plate-like form, and is mainly composed of a roof tile main part A, an underlap part B, an overlap part C, and a connection part D.

The underlap portion B is provided on one side of the tile body A in the length direction, and at the boundary between the tile body A and the underlap B, the underlap portion B is perpendicular to the tile body A. Since the provided connection portion D is interposed, the underlap portion B has a stepped shape with respect to the tile main body portion A. on the other hand,
The overlap portion C is provided in the length direction on the other side of the roof tile body portion A (see FIG. 7).

When the flat tile H is laid on the roof, the underlap portion B of the flat tile H is located below the overlap portion C of another flat tile H adjacent to one side. Is located above the underlap portion B of yet another flat tile H adjacent to the other side, and the surface of the tile main body A has the same height as the surface of the tile main body A of the flat tile H adjacent to both sides. A flat continuous surface is formed in the width direction.

The flat roof tile H is formed by continuously extruding a clay raw material containing water in the same manner as a normal Japanese roof tile (J-type clay tile), and pressing an extruded body E cut to a predetermined size. (See FIG. 8).

[0006] Then, the molding base H obtained by pressure molding (the same sign as the finished flat roof tile H because of the similar shape) is subjected to processing such as drying, glaze and firing. Thus, a flat tile H as a finished product is obtained.

However, since the flat roof tile H is substantially plate-shaped, the cut extruded body E is pressure-formed by a press machine equipped with a molding die G corresponding to the flat roof tile H. (See FIG. 9).

[0008] However, the boundary between the tile body A and the underlap portion B is formed into a step shape by pressure molding in the state of the plate-like extruded body E, but the molding base obtained by the pressure molding is formed. In the vicinity of the boundary between the tile body portion A and the underlap portion B in H, since the shape is substantially perpendicular to the horizontal direction and again in the horizontal direction, the molding base H
The raw material is more susceptible to the resistance of the molding pressure by the molding die G than the other parts, and there is a possibility that the raw material does not sufficiently reach the molding die G inside the molding die G.

In particular, in the vicinity of the connection portion D near the boundary between the tile body portion A and the underlap portion B in the molding base H, entrainment P of the raw material or insufficient filling Q occurs, and the flat tile becomes defective in appearance. In addition to reducing the commercial value, there is a problem that the strength of the product is insufficient (see FIG. 9).

Further, in the vicinity of the connection portion D in the molding base H, a difference occurs due to a difference in the density of the raw materials due to the step-like form at the time of the pressure molding. This causes distortion and cracks near the boundary between the tile body A and the underlap B during firing.

In addition, since the boundary between the tile body A and the underlap B is formed in a stepped shape, the connecting portion D at the boundary between the two A and B is press-formed compared with other portions of the forming base H. , The orientation of the raw clay particles is significantly different. As a result, the remarkable difference in the orientation of the clay particles in the molding base H caused distortion and cracks near the boundary between the tile body A and the underlap B during drying and firing.

[0012]

The problem to be solved by the present invention is that in the production of conventional flat roof tiles, at the time of pressure molding, the vicinity of the boundary between the tile body portion and the underlap portion of the green body is formed. In addition to the fact that the density of the raw material differs from the other parts of the forming base, distortion and cracks occur during drying and firing, as well as the formation near the boundary between the tile body part and the underlap part of the forming base A significant difference in the orientation of the clay particles in the base material compared to other parts is generated, which, together with the difference in the density of the raw materials, further promotes distortion and cracking during drying and firing.

An object of the present invention is to alleviate the difference in the density of the raw materials near the boundary between the tile body portion and the underlap portion of the molding base during the pressure molding of the flat roof tile, and to reduce the orientation of the clay particles. An object of the present invention is to provide a method of manufacturing a flat roof tile that does not cause a significant difference and suppresses distortion and cracks generated near the boundary between the roof main body portion and the underlap portion during drying or firing.

[0014]

In order to achieve the above object, a method for manufacturing a flat roof tile according to claim 1 is to extrude a clay raw material to obtain a plate-like extruded product. In the method of manufacturing a flat roof tile to obtain a molding base by press-molding a shaped extruded body, a connection portion is formed between the tile body portion and the underlap section of the formed base by press-molding the extruded body. In addition to the above, the connection portion is inclined at 30 to 60 degrees from the underlap portion to the tile body portion.

Therefore, in the method for manufacturing a flat tile according to the first aspect, a connection portion is provided between the tile main body portion and the underlap portion of the formed base by press-molding the extruded body, and the underlap is provided. 3 from the roof to the roof body
Since the connection portion inclined at 0 to 60 degrees is provided, the raw material in the pressure molding easily spreads in the molding die, and the density of the raw material in the connection portion which is the boundary between the main body portion and the underlap portion of the molding base is: The difference is reduced as compared with the other parts, and distortion and cracks, which are likely to occur in the connection part at the boundary between the main body part and the underlap part of the molded body during drying or firing, are suppressed.

Further, by press-molding the extruded body, the connecting portion, which is the boundary between the main body portion and the underlap portion of the molding base, is inclined at 30 to 60 degrees. Therefore, the orientation of the clay particles at the connection portion, which is the boundary between the main body portion and the underlap portion of the forming base, is suppressed from being different from other portions in conjunction with the mitigation of the difference in the density of the raw material, and the Strain and cracks, which are likely to occur near the boundary between the tile body and the underlap during firing, are further suppressed.

According to a second aspect of the present invention, there is provided a method of manufacturing a flat roof tile according to the first aspect, wherein the extruded body is provided with a tile body scheduled portion, an underlap scheduled portion and a connection scheduled portion. The cross-sectional shape of the molded body substantially corresponds to the cross-sectional shape in the width direction of the molding base from the planned underlap portion to the connection planned portion and the tile body planned portion.

Therefore, the method for manufacturing a flat roof tile according to the second aspect has the same effect as that of the drying method according to the first aspect. Along with the provision of the lap scheduled portion and the planned connection portion, the cross-sectional form of the extruded body substantially corresponds to the cross-sectional shape in the width direction of the molding base from the planned underlap portion to the planned connection portion and the tile body planned portion. The raw material in the pressure molding becomes easier to spread inside the molding die, and the density of the raw material at the connection part, which is the boundary between the tile body part and the underlap part of the molding base, is further reduced from the other parts. Thus, during drying or firing, distortion and cracks, which tend to occur at the connection portion, which is the boundary between the tile body portion and the underlap portion, of the forming base are drastically suppressed.

In addition, at the time of pressure molding, the orientation of the clay particles in the connection portion, which is the boundary between the tile body portion and the underlap portion of the molding base, is further reduced from the difference between the other portions and the raw material. Combined with further alleviation of the difference in density, strains and cracks, which tend to occur near the boundary between the tile main body portion and the underlap portion during drying or firing, are further suppressed.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing a flat tile according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a molded body in a method of manufacturing a flat roof tile according to an embodiment of the present invention, as viewed from the front, FIG. 2 is a cross-sectional view of an extruded body before being subjected to pressure molding, and FIG. FIG. 4 is an enlarged view of a main portion showing the state of the density of the raw material of the molding base and the orientation of the clay particles, and FIG. 5 is a molding base of the flat roof tile according to this embodiment. , FIG. 6 is a cross-sectional view of an extruded body according to another embodiment as viewed from the front, FIG. 7 is a perspective view of a flat roof tile according to the related art, and FIG. 8 is an extruded body according to the related art. Perspective view, FIG. 9
FIG. 2 is a cross-sectional view of a main part showing the state of density and orientation of a green body at the time of pressure molding in a conventional technique.

(Regarding Extruded Molded Body) The extruded molded body 10 is obtained by an extruder, and is cut into a predetermined size for pressure molding in a later step. The extruded body 10 is substantially plate-shaped, and is composed of a planned tile body portion 12, a planned underlap portion 14, a planned connection portion 16, and a planned overlap portion 18 (see FIG. 2).
Then, the extruded body 10 is subjected to pressure molding to form a molding base 30 described later.

The tile main body scheduled portion 12 is a portion corresponding to the tile main body portion 32 in the molding base 30, and the extruded body 10
Accounts for most of the The scheduled tile body portion 12 is in a horizontal state, and is provided with a scheduled connection portion 16 that is inclined slightly downward from one side of the tile body scheduled portion 12 (see FIG. 2).

The connecting portion 16 is a connecting portion 3 of the molding base 30.
6, and the planned connection portion 16 in this embodiment is inclined downward by 35 degrees toward the planned underlap portion 14.

The planned underlap portion 14 is provided from one side of the planned connection portion 16 in the horizontal direction, and is a portion corresponding to the underlap portion 34 of the forming base 30. On the other hand, an expected overlap portion 18 is provided on the other side of the tile main body expected portion 12, and corresponds to the overlap portion 38 of the molding base 30.

Further, in this embodiment, the bulging portions 22 corresponding to the reinforcing ribs 42 provided on the back surface of the molding base 30 are provided at three locations in the tile body scheduled portion 12 at predetermined intervals. .

As described above, the extruded body 10 according to this embodiment has an underlap scheduled portion 14, a connection scheduled portion 16, a tile main body scheduled portion 12, and an overlap scheduled from one side to the other side in cross section. The unit 18 is configured in this order.

The portions in the horizontal state are the planned overlap portion 18, the planned tile body portion 12, and the planned underlap portion 14, and the planned connection portion 16 is inclined. In the cross section of the extruded body 10,
A line passing substantially through the center of the planned overlap portion 18 is defined as a center line M, a line passing substantially through the center of the planned underlap portion 14 is defined as a center line N, and a line passing substantially through the center of the planned connection portion 16 is defined as a center. Assuming that the line is Y, the center lines M and N are parallel to each other, and the acute angle formed by the center lines Y and N is 35 degrees.

The reason for inclining the connecting portion 16 of the extruded body 10 is that one side of the tile main body portion 32 in the forming base 30, the connecting portion 36, the connecting portion 36 and the underlap portion 34 are formed at the time of pressure forming described later. In other words, in the vicinity of the boundary between the tile body portion 32 and the underlap portion 34, a significant difference in the orientation of the clay particles due to the pressure molding is suppressed.

That is, the portion 18 to be overlapped, the majority of the portion 12 to be tiled, and the portion 14 to be underlap 14 in the extruded body 10 are in a horizontal state. Since the particles are in a horizontal state, the change in the orientation of the particles is small.

On the other hand, the vicinity of the connection scheduled portion 16 of the extruded body 10, that is, the vicinity of the boundary between the tile body planned portion 12 and the underlap planned portion 14, is formed into a substantially right-angled step shape on the forming base 30 by pressure molding. Then, the change is large compared to the change in the shape of the planned tile main body portion 12, the planned underlap portion 14, and the planned overlap portion 18 in the horizontal state.
The orientation of the particles in the vicinity of the boundary changes significantly.

Therefore, a portion where the change in the orientation of the clay particles is large and a portion where the change is small occur in the forming base 30, and the orientation of the particles in the forming base 30 is significantly different depending on the portion. This remarkable difference in the orientation of the clay particles causes distortion or cracks in the molding base 30 during drying or firing, and tends to occur in a portion where the orientation of the clay particles greatly changes.

In this embodiment, the change in the orientation of the particles near the boundary between the planned tile body portion 12 and the planned underlap portion 14 during pressure molding is suppressed, and the orientation of the clay particles in the molding base 30 is suppressed. In order to prevent the properties from being significantly different from part to part, from the one side of the tile body scheduled part 12 of the extruded body 10, the connection scheduled part 16 and the underlap scheduled part 14 will be described. Connecting portion 36 and underlap portion 34 from one side
It substantially corresponds to the cross-sectional form reaching the boundary with.

In particular, in this embodiment, the angle of inclination of the connecting portion 16 of the extruded body 10 is about 35 degrees. The connecting portion 36 from 35 degrees of the scheduled portion 16
To 45 degrees, and the difference is 10 degrees (FIG. 1).
And FIG. 2).

According to the test of the inventor, if the change in the inclination angle of the connection scheduled portion 16 due to the pressure molding is within 20 degrees,
It has been confirmed that distortion and cracks during drying and firing are more effectively suppressed, and the difference in the orientation of the clay particles and the density of the raw material in the molding base 30 is nothing but the suppression.

Therefore, in the case of the present embodiment in which the inclination angle of the connecting portion 36 in the forming base 30 is 45 degrees, the inclination angle of the connecting portion 16 may be freely set in the range of 25 to 45 degrees.

When the angle of inclination of the connecting portion 36 in the molding base 30 is set in the range of 30 to 60 degrees, the angle of inclination of the connecting portion 16 in the extruded body 10 is set to be equal to that of the connecting portion 36 and the connecting portion 16. Since the angle difference may be within 20 degrees, the minimum is 10 degrees and the maximum is 50 degrees, which is in a range substantially corresponding to the cross-sectional shape of the forming base 30 in the width direction.

From one side of the tile body scheduled portion 12 to the connection scheduled portion 1
6. Extruded body 10 obtained by extrusion is provided by continuously providing planned underlap portions 14 and extruding so that the inclination angle of planned connection portion 16 is about 35 degrees.
Since the cross-sectional shape in the width direction substantially corresponds to the cross-sectional shape in the width direction of the molding base 30, the resistance of the raw material to the molding die in the pressure molding is reduced, and the raw material easily spreads sufficiently in the molding die.

Therefore, the density of the raw material in the vicinity of the boundary between the tile body 32 and the underlap portion 34 in the molding base 30 does not greatly differ from the other portions, and the orientation of the clay particles described above is not changed. Combined with the suppression of remarkable differences in properties, distortion and cracks during drying and firing due to differences in the density of the raw materials can be suppressed.

In this embodiment, in order to obtain a more preferable molding base 30 for suppressing distortion and cracks, the extruded molded body 10 is provided with the inclined connecting portion 16.
Even if a plate-shaped extruded body is simply employed without providing the inclined connection scheduled portion 16 as in the conventional case, the difference in the density and the orientation of the raw materials of the molding base obtained by the pressure molding is suppressed. Needless to say.

(Regarding the forming base) The forming base 30 according to this embodiment includes
4, connecting portion 36, overlapping portion 38, reinforcing rib 42
In terms of form, there is no difference from a flat tile as a product.

The forming substrate 30 in this embodiment is:
It is obtained by press-molding the extruded body 10, and a specific means of the press-forming is a press mold and a mold comprising an upper mold 44 and a lower mold 46 attached to the press machine. (See FIGS. 2 and 3).

The forming substrate 30 in this embodiment is:
An overlap portion 38 is provided on the other side of the tile main body 32, while three reinforcing ribs 42 are provided on the back surface of the tile main body 32.
Are provided to improve the strength of the tile main body 32. The underlap portion 34 is provided via the connecting portion 36 so as to be stepped with respect to the tile main body 32. A connection portion 36 inclined at 45 degrees in the width direction is provided between the underlap portion 34 and the tile main body portion 32.

In the cross section of the forming base 30, a line passing substantially through the center of the tile body 32 and the overlap portion 38 is defined as a center line m, and a line passing through the center of the planned underlap portion 34 is defined as a center line n. Assuming that a line passing through the center of the connection scheduled portion 36 is a center line x, the center lines m and n are parallel to each other, and an acute angle formed by the center lines x and n is 4
5 degrees.

Since the connecting portion 36 is inclined differently from the conventional one, the orientation of the clay particles in the connecting portion 36 which has been subjected to pressure molding is different from that of the other portions (the tile main body portion 32, the underlap portion 34, There is no significant difference compared to the wrap portion 38).

That is, the roof tile main body portion 32, the underlap portion 34 and the overlap portion 38 are formed from the extruded body 10 into the forming base 30, but the horizontal state is basically maintained and the change in the form is small. .

However, in order to maintain the function as a flat tile, the underlap portion 34 and the tile main portion 32 must be provided in a stepped shape with respect to each other.

Then, the connection portion 36 is press-formed so as to be inclined at 45 degrees, but the connection portion 36 is inclined within a range where the function of the flat roof tile is maintained, and the connection portion 36 is moved from the extruded body 10 to the molding base 30. It is intended to suppress a change in the form of the connection portion 36 in the molding of the first embodiment. Since the change in the form of the connection portion 36 is suppressed, the change in the orientation of the clay particles in the connection portion 36 in the molding from the extruded body 10 to the molding base 30 is small, and the clay particles are smaller than the other portions. The remarkable difference in the orientation of the particles is suppressed (see FIG. 4).

Therefore, since there is no significant difference in the orientation of the clay particles depending on the position of the molding base 30, distortion and cracks during drying and firing are suppressed.

Further, by performing pressure molding so that the connecting portion 36 is inclined at 45 degrees, the resistance of the raw material to the molding die is reduced, and the raw material easily spreads sufficiently in the molding die. The density of the raw material in the vicinity of the boundary between the main body portion 32 and the underlap portion 34 does not greatly differ from other portions, and the above-mentioned point that the marked difference in the orientation of the clay particles is suppressed is suppressed. In addition, it is possible to suppress distortion and cracks during drying and firing due to the difference in density of the raw materials (see FIG. 4).

In this embodiment, as the most preferable example, the tile body scheduled portion 12 of the extruded body 10,
The connection planned portion 16 and the underlap planned portion 14 are provided, and the extrusion is performed so that the inclination angle of the connection planned portion 16 becomes 35 degrees, and the connection portion 36 between the tile body portion 32 of the forming base 30 and the underlap portion 34 is formed. This is an example in which the obtained extruded body 10 is pressure-formed so as to be inclined at 45 degrees in the width direction.

In this case, it is possible to obtain the extruded body 10 provided with the connection scheduled portion 16 described above,
Due to the synergistic effect of press-molding the extruded body 10 so that is inclined, distortion and cracks of the obtained molded body 30 during drying and firing are remarkably suppressed.

However, the advantages described above can be obtained without impairing the function of the flat roof tile if the connecting portion 36 of the molding base 30 has an inclination angle in the range of 30 to 60 degrees.

Next, an extruded product according to another embodiment will be described. The extruded body 50 of this embodiment substantially corresponds to the cross-sectional shape of the molding base 30 in the width direction, and is similar to the previously described embodiment.
2. It is provided with the planned underlap portion 54, the planned connection portion 56, the planned overlap portion 58, and the bulged portion 62, and the portion from the tile main body planned portion 50 to the planned underlap portion 54 through the planned connection portion 56 is formed. It has a mountain shape (see FIG. 6).

The mountain-shaped configuration is composed of a main body inclined portion 64 of the roof tile main body 52 and a connection inclined portion 66 of the expected connection portion 56. The inclination angle of the main body inclined portion 64 is 15
The inclination angle of the connection inclined portion 66 is 25 degrees (see FIG. 6).

In the cross section of the extruded body 50, the presumed tile main body portion 52 except for the main body inclined portion 64, the overlap portion 58.
A line passing substantially through the center of the planned underlap portion 54 is defined as a center line a, a line passing through the center of the planned connection portion 56 is defined as a center line b, and passes through the center of the main body inclined portion 64 in the tile main body planned portion 52. Assuming that the line is the center line c, the acute angle formed by the center lines a and b is 25 degrees, while the acute angle formed by the center lines b and c is 15 degrees.

By using the extruded body 50 of this embodiment, handling of the extruded body 50 on the conveying surface becomes easy, for example, the conveying device such as a conveyor is not complicated in conveying the extruded body 50. Has advantages.

Then, the extruded body 50 according to this embodiment is subjected to pressure molding, whereby the molding base 30 described in the previous embodiment is obtained. Needless to say, cracks and cracks are suppressed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a molding base in a method of manufacturing a flat roof tile according to an embodiment as viewed from the front.

FIG. 2 is a cross-sectional view of the extruded body before pressure molding as viewed from the front.

FIG. 3 is a cross-sectional view of a molding base after pressure molding as viewed from the front.

FIG. 4 is an enlarged view of a main part showing the state of the density of the raw material of the molding base and the orientation of the clay particles.

FIG. 5 is a perspective view of the flat roof tile according to the embodiment.

FIG. 6 is a cross-sectional view of an extruded body according to another embodiment as viewed from the front.

FIG. 7 is a perspective view of a flat tile according to the related art.

FIG. 8 is a perspective view of an extruded product according to a conventional technique.

FIG. 9 is a cross-sectional view of a main part showing the state of the density and the orientation of a green body at the time of pressure molding in the conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Extrusion molded body 12 Presumed part of a tile body 14 Underplanned underlap part 16 Planned connection part 18 Planned overlap part 22 Swelling part 30 Molding base 32 Tile body part 34 Underlap part 36 Connection part 38 Overlap part 42 Reinforcement rib 44 Above Mold 46 Lower mold 50 Extruded molded body 52 Tiled body scheduled part 54 Underlap scheduled part 56 Planned connection part 58 Planned overlap part 62 Swelling part 64 Body inclined part 66 Connection inclined part A Tiled body part B Underlap part C Overlap Part D Connection part E Extruded body G Mold H Flat roof tile (molded base) P Entrapment Q Insufficient filling

Claims (2)

[Claims] 1. A method for manufacturing a flat roof tile, wherein a plate-shaped extruded product is obtained by extruding a clay raw material, and the plate-shaped extruded product is pressure-formed to obtain a forming base. By press-forming, a connection portion is provided between the tile body portion and the underlap portion of the forming base, and the connection portion is moved from the underlap portion to the tile body portion.
A method for manufacturing a flat roof tile, characterized by being inclined at 0 to 60 degrees. 2. An extruded body is provided with a planned tile body portion, a planned underlap portion and a planned connection portion, and the cross-sectional form of the extruded body is formed from the planned underlap portion to the planned connection portion and the planned tile body portion. 2. The method for manufacturing a flat roof tile according to claim 1, wherein the cross-sectional shape substantially corresponds to the cross-sectional shape in the width direction.