JPH05230937A - Light tile and production thereof - Google Patents

Abstract

PURPOSE:To provide a light tile which prevents damages from the periphery of the tile body to provide the practical strength, gives a uniform compression density to keep away a superficial hollow and further, forming a sintered layer at the ribs on the rear of tile body in order to increase the strength. CONSTITUTION:The thickness of a tile is made thin except the periphery around the tile body 3 and a groove is formed in the lateral direction of the tile body 3. And ribs 26 constituted of the first recession are formed in the tile body 3. The surface is shaped uneven in correspondence with hollows due to uneven compression density. The thickness of the tile body 3 is made thin and a sintered layer is formed by a specially combined glaze 33.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightweight roof tile for reducing the weight of clay roof tile and a method for manufacturing the lightweight roof tile.

[0002]

2. Description of the Related Art Conventionally, it has been desired in recent years to reduce the weight of clay roof tiles due to the problems of resource depletion, fuel consumption, freight, and workability.
Conventionally, the wall thickness of the same base material is simply thinned to reduce the weight, but with this clay tile, cracks, chips, etc. easily occur from the periphery, and the whole is damaged. Besides, it has a drawback that the bending strength, which is the standard value of clay roof tiles, cannot be satisfied.

Further, as a means for reducing the weight by forming a large number of concave portions on the back surface of the clay roof tile by providing honeycomb-shaped ribs, etc., as shown in FIG. Since the end surface c is flat, a depression g is generated on the surface f of the base material e facing the concave portion d of the mold a during press molding, which has a drawback that the commercial value as a roof tile is reduced. There is.

Further, according to this manufacturing means, in the clay tile made of non-uniform compression density at the time of press molding, that is, a clay having a low plasticity, although the density at the lower end surface c of the protrusion b is high, Since the density in the recessed part d flowing into the recessed part is low, the rib h, which is a thin portion filled in the recessed part d, may be cracked or chipped by a slight impact. Although it is possible to reduce the weight in terms of structural mechanics, the clay roof tile has a drawback in that it cannot be reduced in weight because strength cannot be expected according to the theoretical value and strength is reduced.

[0005]

DISCLOSURE OF THE INVENTION The present invention prevents damage from around the roof tile body, has sufficient practical strength, makes the compression density uniform at the time of press molding, and causes the occurrence of surface depressions. Loss of product value is prevented, and the depressions that occur on the surface during molding are made inconspicuous to prevent a decrease in product value.
Further, it is possible to obtain the strength as the theoretical value by advancing the firing degree of the surface layer portion such as the ribs formed by the back surface of the roof tile body and the concave portion of the back surface from the base layer portion to form a sintered layer having a predetermined thickness. At the same time, it is intended to provide a lightweight roof tile and a method for manufacturing the lightweight roof tile, which are formed by increasing the apparent wall thickness to make the roof tile lighter than the conventional products in terms of strength.

[0006]

SUMMARY OF THE INVENTION In view of the problems such as insufficient strength, dents formed on the surface, and uneven compression density, the present invention is based on the above-mentioned prior art. Second, a groove is formed in the lateral direction of the roof tile main body, and the shape of the groove is formed to have a uniform compression density during press molding. Thirdly, the groove is formed in the roof tile main body. The uniform compression density of the honeycomb-shaped ribs composed of a large number of the first concave portions, and the fourth, the surface pattern due to the uneven compression density of the honeycomb-shaped ribs composed of a large number of the second concave portions is inconspicuous. Fifthly, the above drawbacks should be solved by providing a lightweight roof tile and a method for manufacturing a lightweight roof tile, which is characterized in that the decrease in strength due to the thin wall of the roof tile body is compensated by a glaze with a special composition. It was done.

First, in the lightweight roof tile of claim 1, the peripheral portion of the back surface of the roof tile body is left with a predetermined width to form a recessed portion having a predetermined depth.

Next, in the lightweight roof tile of claim 2, a large number of groove portions having a V-shaped cross section are provided in parallel in the lateral direction inward of the peripheral portion on the back surface of the roof tile body having the peaks and valleys. ..

Next, in the lightweight roof tile of claim 3, a honeycomb-shaped rib is formed inside the peripheral portion on the back surface of the roof tile main body, and the bottom side of the rib is formed in a cone shape. A large number of first recesses are formed by engraving.

Next, with respect to the lightweight roof tile of claim 4, a honeycomb-shaped rib or the like is formed inside the peripheral portion on the back surface of the roof tile main body, and the rib has a flat bottom side. A large number of second recesses are formed by engraving, and an uneven pattern is appropriately formed on the surface.

Next, in the lightweight roof tile of claim 5, a honeycomb-shaped rib or the like is formed inside the peripheral portion of the back surface of the roof tile body, and the rib has a flat bottom side. A large number of second concave portions are formed by engraving, and a glaze containing a mixture of granular alumina, silica sand, etc. is applied on one surface, and then firing is performed at a temperature at which alumina, silica sand, etc. are not dissolved.

Next, in the method for manufacturing a lightweight roof tile according to claim 6, a part of the back surface of the roof tile body is formed to have a thin wall thickness, and then a glaze having a melting point lower than that of the roof tile body is applied to at least a part of the back surface. Then, it is fired at 950 ° C. to 1300 ° C. to promote the degree of sintering of the surface layer portion of the base material from the base layer portion.

[0013]

According to claim 1 of the present invention, damage from the periphery of the roof tile main body is prevented and the strength is maintained, and in claims 2 and 3, the compression density is made uniform. , Maintain the strength.

Next, in the fourth and fifth aspects, the pattern formed on the surface and the convex portion 32 formed of insoluble alumina, silica sand or the like appear on the surface generated at the time of molding in the second concave portion. It covers the depression.

Next, in claim 6, the degree of firing of the back surface of the roof tile body and the surface layer portion such as ribs formed by the recesses of the back surface is advanced from the base layer portion to form a sintered layer having a predetermined thickness. Let them do it.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. First, as to the lightweight roof tile W1a according to claim 1, as shown in FIG. 1 to FIG. A roof tile body 3 of a Japanese type having a wall thickness of about 16 mm on average is formed by curving upwardly toward the other side from the peak portion 1 to form a valley portion 2. A bottom notch 4 is formed at the corner of the tail side, and a head notch 5 is formed at the corner of the head side.

A pair of left and right hooks 7 and 7a are provided on the rear side of the rear surface 6, a stabilizing piece 8 is provided, and a jetty 10 is continuously provided on the rear side and the insertion side of the front surface 9. , A fitting portion into which the stable piece 8 is fitted in the jetty 10 at the time of stacking and stacking
11 are provided.

A peripheral portion 12 on the back surface 6 of the roof tile body 3
Recessed part with a predetermined width and the average depth is about 8 mm
Forming thirteen.

The periphery of the depression 13 is formed in a taper shape.

A lightweight roof tile W according to another embodiment of claim 1
As for 1b, as shown in FIGS. 9 to 16, a ridge portion 1 is formed so as to bulge on one side, and a valley portion 2 is formed by gently bending upward from the ridge portion 1 toward the other side. The roof tile 3 has a wall thickness of about 16 mm on average, and a bottom notch 4 is formed at the corner of the roof side and a head notch 5 is formed at the corner of the head side.

At the corners of the tail notch 4, a bottom projection piece 14 having a rectangular shape in plan view is formed in a step shape from the front surface 9, that is, the bottom projection piece 14 has a thickness smaller than that of the roof tile body 3, and the back surface 6 is formed. The butt projections 15 are formed so as to be flush with each other, and the butt projections 15 are formed laterally at the butt side end portions of the butt projection pieces 14 to form the butt fitting portions 16.

At the corners of the head notch 5, a head projection piece 17 having a rectangular shape in plan view is formed in a paragraph shape from the front surface 9, that is, the wall thickness of the head projection piece 17 is made thinner than that of the roof tile body 3, and the back surface 6 is formed. The head projection piece 17 is formed so as to be flush with the outside, and the head projection strip 18 is provided at the insertion side end portion of the head projection piece 17 in the vertical direction to form a head fitting portion 19.

Further, on the back surface 6 of the roof tile body 3, when the tail notch 4 and the head notch 5 are butted against each other, the tail fitting portion 16 is provided.
A head-fitting recess 20 that is slightly larger than the hip-fitting portion 16 is formed in a portion where the head-fitting concave portion 20 overlaps with the tail fitting portion.

Further, in the rear surface 6 of the roof tile body 3, a tail fitting recess 21 which is slightly larger than the head fitting portion 19 is engraved in a portion overlapping the head fitting portion 19 in the same manner as described above. is doing.

Further, a jetty 10 is continuously provided on the butt side and the insertion side of the surface 9 of the roof tile body 3, and the jetty 10 on the butt side is provided.
Is formed in the valley portion 2 in the front of the step 2 through a step portion, and the valley portion 2 in front of the jetty 10 on the insertion side is formed.
A two-step insertion water baffle 23 is formed through the stepped portion.

A pair of left and right hooks 7 and 7a are provided on the rear side of the back surface 6.

In addition, the peripheral portion 12 on the back surface 6 of the roof tile body 3
Recessed part with a predetermined width and the average depth is about 8 mm
Forming thirteen.

Next, as to the lightweight roof tile W2a according to the second aspect, as shown in FIGS. 17 to 24, the ridge portion 1 is formed so as to bulge out to one side, and the ridge portion 1 is directed toward the other side. The roof tile 3 is a Japanese-style roof tile body 3 having an average thickness of about 16 mm by gently bending upward to form a trough portion 2, and the tail side corner portion of the roof tile body 3 has a bottom notch 4 and a head side corner. A head cut 5 is formed in the portion.

A pair of left and right hooks 7 and 7a are provided on the rear side of the back surface 6, a stabilizing piece 8 is provided, and a jetty 10 is continuously provided on the rear side and the insertion side of the front surface 9. , A fitting portion into which the stable piece 8 is fitted in the jetty 10 at the time of stacking and stacking
11 are provided.

Further, the peripheral portion 12 on the back surface 6 of the roof tile body 3
To a predetermined width, and inwardly of the peripheral portion 12, groove portions 24, 24a having a V-shaped cross section extending laterally from one side to the other side.
A large number of ... are provided in parallel.

Regarding the depth of the grooves 24, 24a, ..., The deepest portion is an average of about 8 mm from the back surface 6 (about 1/2 of the wall thickness), and the opening angle .theta. Of each groove 24, 24a. It is 90 degrees.

The opening angle θ of the grooves 24, 24a ... Is not limited at all.

Further, as a lightweight roof tile W2b which is another embodiment of the lightweight roof tile W2a, as shown in FIG.
Leave the peripheral part 12 in the specified width for a specified width and make the average depth 4
A recessed portion 13 having a size of about mm is provided, and the groove portions 24, 24a ... Are provided in parallel in the recessed portion 13.

A lightweight roof tile W according to another embodiment of claim 2
As for 2c, as shown in FIGS. 26 to 33, a ridge portion 1 is formed so as to bulge on one side, and a valley portion 2 is formed by gently bending upward from the ridge portion 1 toward the other side. The roof tile 3 has a wall thickness of about 16 mm on average, and a bottom notch 4 is formed at the corner of the roof side and a head notch 5 is formed at the corner of the head side.

At the corners of the tail notch 4, a bottom projection piece 14 having a rectangular shape in plan view is formed in a step shape from the front surface 9, that is, the bottom projection piece 14 has a thickness smaller than that of the roof tile body 3, and the rear surface 6 is formed. The butt projections 15 are formed so as to be flush with each other, and the butt projections 15 are formed laterally at the butt side end portions of the butt projection pieces 14 to form the butt fitting portions 16.

At the corners of the head notch 5, a head projection piece 17 having a rectangular shape in plan view is formed in a paragraph shape from the front surface 9, that is, the wall thickness of the head projection piece 17 is made smaller than that of the roof tile body 3, and the back surface 6 is formed. The head projection piece 17 is formed so as to be flush with the outside, and the head projection strip 18 is provided at the insertion side end portion of the head projection piece 17 in the vertical direction to form a head fitting portion 19.

Further, on the back surface 6 of the roof tile body 3, when the tail notch 4 and the head notch 5 are butted against each other, the tail fitting portion 16 is provided.
A head-fitting recess 20 that is slightly larger than the hip-fitting portion 16 is formed in a portion where the head-fitting concave portion 20 overlaps with the tail fitting portion.

Further, on the rear surface 6 of the roof tile body 3, a tail fitting recess 21 which is slightly larger than the head fitting portion 19 is engraved in a portion overlapping the head fitting portion 19 in the same manner as described above. is doing.

Further, a jetty 10 is continuously provided on the rear side and the insertion side of the surface 9 of the roof tile body 3, and the jetty 10 on the rear side is provided.
Is formed in the valley portion 2 in the front of the step 2 through a step portion, and the valley portion 2 in front of the jetty 10 on the insertion side is formed.
A two-step insertion water baffle 23 is formed through the stepped portion.

A pair of left and right hooks 7 and 7a are provided on the rear side of the rear surface 6.

In addition, the peripheral portion 12 on the back surface 6 of the roof tile body 3
To a predetermined width, and inwardly of the peripheral portion 12, groove portions 24, 24a having a V-shaped cross section extending laterally from one side to the other side.
A large number of ... are provided in parallel.

Regarding the depth of the groove portions 24, 24a, ..., The deepest portion is an average of about 8 mm from the back surface 6 (about 1/2 of the wall thickness), and the opening angle θ of each groove portion 24, 24a. It is 90 degrees.

The opening angle θ of the groove portions 24, 24a ... Is not limited at all.

Further, as a lightweight roof tile W2d which is another embodiment of the lightweight roof tile W2c, as shown in FIG.
The peripheral part 12 (not shown) in
The recessed portion 13 having a depth of about 4 mm on average is provided, and the recessed portion 13
A large number of the above-mentioned groove portions 24, 24a are provided in the inside.

Next, as to the lightweight roof tile W3a according to claim 3, as shown in FIGS. 35 to 42, the mountain portion 1 is formed so as to bulge out to one side, and the mountain portion 1 is directed to the other side. The roof tile 3 is a Japanese-style roof tile body 3 having an average thickness of about 16 mm by gently bending upward to form a trough portion 2, and the tail side corner portion of the roof tile body 3 has a bottom notch 4 and a head side corner. A head cut 5 is formed in the portion.

A pair of left and right hooks 7 and 7a are provided on the rear side of the rear surface 6, a stabilizing piece 8 is provided, and a jetty 10 is continuously provided on the rear side and the insertion side of the front surface 9. , A fitting portion into which the stable piece 8 is fitted in the jetty 10 at the time of stacking and stacking
11 are provided.

In addition, the peripheral portion 12 on the back surface 6 of the roof tile body 3
To a predetermined width, and inside the peripheral portion 12, the first concave portion is formed.
Many ribs 25, 25a, ... Are engraved to form ribs 26 having a honeycomb shape or the like.

The shape of the first recesses 25, 25a ... Has a hexagonal shape, a square shape, a triangular shape, a circular shape or the like in plan view, and is carved at a depth of about 1/2 of the wall thickness of the roof tile body 3. And each first recess 25, 25a
A flat surface is not formed on the bottom of.

That is, the molding surface of the mold 27 during press molding
The tip side of the molding protrusions 29, 29a, etc. provided on the 28 is formed into a hexagonal pyramid shape with a spherical shape at the tip portion if the hexagonal columnar molding protrusion 29 is formed. Formed in the shape of a quadrangular pyramid, and shaped like a triangular prism 29b
If it is, the tip portion is formed into a triangular pyramid shape that is spherical, and if it is a cylindrical shaped projection 29c, the tip portion is formed into a cone shape that is spherical, or as another embodiment, the whole is a hexagonal pyramid, Formed in the shape of a quadrangular pyramid, a triangular pyramid, and a cone, and the shaped protrusions 29, 29a.
The first recesses 25, 25a are engraved by.

Further, the interval between the first recesses 25, 25a, ... Is set to about 1/2 of the wall thickness of the roof tile body 3, and the back surface 6 is provided with a uniform distribution density (not shown). ), And the depths of the first recesses 25, 25a ... Are deepened as the depth of the central portion of the back surface 6 shifts to the peripheral portion, and the mutual spacing is reduced to increase the distribution density (not shown). ) Etc. can be changed as appropriate.

A lightweight roof tile W according to another embodiment of claim 3
As for 3b, as shown in FIGS. 43 to 50, a ridge portion 1 is formed so as to bulge out to one side, and a valley portion 2 is formed by gently bending upward from the ridge portion 1 toward the other side. The roof tile 3 has a wall thickness of about 16 mm on average, and a bottom notch 4 is formed at the corner of the roof side and a head notch 5 is formed at the corner of the head side.

At the corners of the tail notch 4, a bottom projection piece 14 having a rectangular shape in plan view is formed in a paragraph shape from the front surface 9, that is, the bottom projection piece 14 has a thickness smaller than that of the roof tile body 3, and the back surface 6 is formed. The butt projections 15 are formed so as to be flush with each other, and the butt projections 15 are formed laterally at the butt side end portions of the butt projection pieces 14 to form the butt fitting portions 16.

At the corners of the head notch 5, a head projection piece 17 having a rectangular shape in plan view is formed in a paragraph shape from the front surface 9, that is, the wall thickness of the head projection piece 17 is made thinner than that of the roof tile body 3, and the back surface 6 is formed. The head projection piece 17 is formed so as to be flush with the outside, and the head projection strip 18 is provided at the insertion side end portion of the head projection piece 17 in the vertical direction to form a head fitting portion 19.

Further, on the back surface 6 of the roof tile main body 3, when the tail notch 4 and the head notch 5 are butted against each other, the tail fitting portion 16 is provided.
A head-fitting recess 20 that is slightly larger than the hip-fitting portion 16 is formed in a portion where the head-fitting concave portion 20 overlaps with the tail fitting portion.

Further, on the back surface 6 of the roof tile main body 3, a tail fitting concave portion 21 which is slightly larger than the head fitting portion 19 is formed in a portion overlapping the head fitting portion 19 in the same manner as described above. is doing.

Further, a jetty 10 is continuously provided on the butt side and the insertion side of the surface 9 of the roof tile body 3, and the jetty 10 on the butt side is provided.
Is formed in the valley portion 2 in the front of the step 2 through a step portion, and the valley portion 2 in front of the jetty 10 on the insertion side is formed.
A two-step insertion water baffle 23 is formed through the stepped portion.

A pair of left and right hooks 7 and 7a are provided on the rear side of the back surface 6.

Further, the peripheral portion 12 on the rear surface 6 of the roof tile body 3
Is left for a predetermined width, and inside the peripheral part 12, a lightweight roof tile W
Similar to 3a, a large number of first recesses 25, 25a ... Are engraved to form ribs 26 of honeycomb shape or the like.

Next, as to the lightweight roof tile W3c according to another embodiment of the third aspect, as shown in FIGS. 51 to 58, the mountain portion 1 is formed so as to bulge out to one side and the mountain portion 1 The roof tile 3 is formed into a Japanese type roof tile body 3 having an average thickness of about 16 mm by gently curving upward toward the other side to form a valley portion 2, and the roof tile body 3 is provided with a skirt at a corner on the butt side. 4 notches, 5 notches on the head side
Is formed.

Further, a jetty 10 is continuously provided on the rear side and the insertion side of the surface 9 of the roof tile body 3, and the jetty 10 on the rear side is provided.
Is formed in the valley portion 2 in the front of the step 2 through a step portion, and the valley portion 2 in front of the jetty 10 on the insertion side is formed.
A two-step insertion water baffle 23 is formed through the stepped portion.

A pair of left and right hooks 7 and 7a are provided on the rear side of the back surface 6.

Further, the peripheral portion 12 on the back surface 6 of the roof tile body 3
Is left for a predetermined width, and the bottom notch 4 and the head notch 4 on the inner side of the peripheral portion 12 extend laterally from one side to the other between the widths of the notch length of the head notch 5. Section V
A large number of V-shaped groove portions 24, 24a are provided in parallel, and these groove portions are further provided.
Grooves 24, 24a, each having a rectangular shape in plan view, are successively and concentrically formed between the grooves 24, 24a.

Next, the operation of the various lightweight roof tiles according to claims 1 to 3 will be described. First, with respect to the lightweight roof tile W1a, since the peripheral portion 12 of the roof tile body 3 is left as it is, Damage such as chipping and scratches in the part is prevented in advance, and the strength does not decrease simply in proportion to the weight reduction rate, so that a certain strength can be maintained.

Next, with respect to the lightweight roof tile W1b, the strength can be maintained in the same manner as described above, and as shown in FIG. 66, when the tail notch 4 and the head notch 5 are butted against each other, the tail fitting portion is
Since 16 and the head fitting recess 20 and the head fitting portion 19 and the buttocks fitting recess 21 are fitted respectively, the head side of the upper lightweight roof tile W1b is pressed by the bottom side of the lower lightweight roof tile W1b, and The head side of the upper lightweight roof tile W1b presses the bottom side of the lower lightweight roof tile W1b, so that the lifting of the head side due to the wind blown from the head side is restricted.

Further, since the tail fitting portion 16 is provided with the tail protrusions 15, the downward displacement (flow direction) of the lightweight roof tile W1b can be restricted, and the head fitting portion 19 can be head-projected. Since the strip 18 is provided, the positional deviation of the lightweight roof tile W1b in the lateral direction (column direction) is restricted.

Next, regarding the lightweight roof tiles W2a and W2c, the pressure is reduced by pressing the molding projections 29d provided on the molding surface 28 of the mold 27 at the tip angle of 90 degrees as shown in FIG. Since it is added as shown by the arrow A, the compression density can be made uniform and the strength can be maintained similarly to the lightweight roof tile W1a.

Next, with respect to the lightweight roof tiles W2b and W2d, the lifting of the head side is restricted similarly to the lightweight roof tile W1b, and the compression density is made uniform like the lightweight roof tiles W2a and W2c.

Next, regarding the lightweight roof tiles W3a, W3b, W3c, as in the lightweight roof tiles W2a, W2c, the compression density is made uniform by the shapes of the groove portions 24, 24a, ... At the same time, the reduction in strength is maintained.

As for the lightweight roof tile W3b, like the lightweight roof tile W1b, lifting on the head side, positional deviation in the lateral direction (column direction), and downward position (flow direction) are restricted.

Next, the experimental results of the bending strength of various lightweight roof tiles according to claims 1 to 3 are shown below. The lightweight roof tile W1a has a weight reduction rate of about 43% and a bending strength of 17%.
The 6 kgf / s lightweight roof tile W1b has a weight reduction rate of about 43% and a bending strength of 17%.
The 5kgf / s lightweight roof tile W2a has a weight reduction rate of about 20% and a bending strength of 20.
The 9kgf / s lightweight roof tile W2b has a weight reduction rate of about 20% and a bending strength of 20.
The 6kgf / s lightweight roof tile W2c has a weight reduction rate of about 20% and a bending strength of 20.
8kgf / s lightweight roof tile W2d has a weight reduction rate of about 20% and a bending strength of 20.
7kgf / s lightweight roof tile W3a has a weight reduction rate of about 15% and a bending strength of 20.
The 2kgf / s lightweight roof tile W3b has a weight reduction rate of about 15% and a bending strength of 20.
The 3kgf / s lightweight roof tile W3c has a weight reduction rate of about 15% and a bending strength of 20.
3 kgf / s On the other hand, regarding the bending strength of the conventional product having a wall thickness of 16 mm and the conventional lightweight product having a wall thickness of 8 mm, the bending strength of the conventional product is 219 kgf / s. Conventional lightweight products have a weight reduction rate of about 50% and a bending strength of 110 kg.
It was f / s.

As the original soil, Mikawa clay (clay collected in Mikawa district of Aichi prefecture) was used for all specimens, and general high silver glaze was glazed on the surface and fired under the same conditions and bent. The strength test was performed based on JIS-A5208.

The composition of Mikawa Clay is that SiO ₂ is 67.1.
Parts by weight, AlO ₃ 19 parts by weight, Fe ₂ O ₃ 4 parts by weight, CaO 0.5 parts by weight, MgO 0.5 parts by weight, Na ₂
O is 0.95 parts by weight, K ₂ O is 2.8 parts by weight, and the others are 4.9 parts by weight.
5 parts by weight, and the composition of the high silver glaze is 46 parts by weight of borosilicate frit, 28 parts by weight of feldspar, 5 parts by weight of silica stone, 8 parts by weight of wollastonite, 12.3 parts by weight of pigment, Bentonite is 0.3 parts by weight and CMC is 0.4 parts by weight.

Next, as shown in FIGS. 60 and 61, for the lightweight roof tile W4 according to the fourth aspect, the peripheral portion 12 on the back surface 6 of the roof tile body 3 having an average wall thickness of about 16 mm is left with a predetermined width. A large number of second recesses 30, 30a ... Are engraved inside the peripheral portion 12 to form a honeycomb-like rib 26.

The shape of the second recesses 30, 30a ...
It has a hexagonal shape, a square shape, a triangular shape, a circular shape or the like in a plan view, and is carved at a depth of about half the wall thickness of the roof tile body 3, and each second recess 30,
A flat surface is formed on the bottom of 30a.

That is, the molding surface of the mold 27 during press molding
The second recesses 30, 30a ... Are engraved with the tip end side of the molding projection 29e provided on the 28 as a flat surface.

Further, an uneven pattern 31 is appropriately formed on the surface 9 of the roof tile body 3.

Next, as a lightweight roof tile W5 according to a fifth aspect, as shown in FIG. 62, the surface of the roof tile body 3 forming the honeycomb-shaped ribs 26 including the second recesses 30, 30a ... A glaze mixed with large-grained alumina, silica sand, etc. is applied to 9 and then baked at a temperature at which alumina, silica sand, etc. are not dissolved to form innumerable convex portions 32 on the surface.

Next, as a method for manufacturing the lightweight roof tile W6 according to claim 6, as shown in FIGS. 63 and 64, the average wall thickness is 16 mm.
A peripheral portion 12 on the back surface 6 of the roof tile body 3 having a certain extent is left for a predetermined width, and a large number of second concave portions 30, 30a ... Are engraved inside the peripheral portion 12 in the same manner as described above to form a honeycomb-shaped rib. 26
And then dried, a glaze 33 having a lower melting point than that of the roof tile body 3 is applied to the central portion 34 which is a part of the back surface 6, the entire back surface 6, or the front and back surfaces. , If it is to be further colored, the surface of the glaze 33 is dried to some extent, and the glaze is appropriately colored (not shown)
Is applied.

In another embodiment, the average wall thickness is 16
The overall thickness of the roof tile body (not shown) having a size of about mm is thinly formed to 8 mm, and glazed in the same manner as above.

The firing degree of the surface layer portion 35 (the portion where the base material of the roof tile body 3 and the glaze 33 are fused and sintered) by firing at 950 ° C. to 1300 ° C. is measured from the base layer portion 36 (inside the base material). By advancing, the sintered layer 37 having a predetermined thickness is formed.

Here, the glaze 33 having a melting point lower than that of the base material naturally varies depending on the fire resistance and firing temperature of the base material, but if the difference in melting point is too small compared to the base material, the progress of sintering of the surface layer portion 35 cannot be achieved. If the melting point is too low, sintering proceeds too far to the center of the substrate and vitrifies, causing twisting, distortion, etc. and abnormal deformation or firing cracking. Therefore, use the firing conditions and glaze concentration (adhesion amount) as a standard. And an appropriate glaze composition.

Further, it is preferable that the glaze composition has a small difference in thermal expansion coefficient from that of the base material, and the composition used in this example is 57.5 parts by weight of SiO ₂ and 3.6 parts of Al ₂ O ₃ .
Parts by weight, 4.3 parts by weight of CaO, 5.2 parts by weight of Na ₂ O,
14 parts by weight of B ₂ O ₃ , 14 parts by weight of ZrO ₂ , PbO
Was performed at 1.4 parts by weight.

The glaze method may be any of pouring, dipping, spraying, etc., but uniform glaze is preferred.

Next, the operation of the various lightweight roof tiles according to claims 4 to 6 will be described below. First, regarding the lightweight roof tile W4 of claim 4, the uneven pattern 31 formed on the surface 9 is described.
By this, the depression g generated during molding is covered.

Next, regarding the lightweight roof tile W5 of claim 5,
Even after glazeing and firing, alumina, silica sand, etc. mixed in the glaze do not dissolve, so that the convex portion 32 is formed on the surface 9,
The hollow g generated during molding is covered.

Next, regarding the lightweight roof tile W6 of claim 6,
The sintering degree of the surface layer portion 35 such as the honeycomb-shaped ribs 26 formed by the back surface 6 of the roof tile body 3 and the second recesses 30, 30a of the back surface 6 is advanced from the base layer portion 36 to a sintered layer 37 of a predetermined thickness. Is formed.

Next, the experimental results of the manufacturing method of claim 6 are shown below. Example 1 A large number of second recesses 30, 30a ... Are engraved on the back surface 6 of the roof tile body 3 having an average wall thickness of about 16 mm. And honeycomb ribs
26, and then dried to apply the glaze 33 to the central portion 34, which is a part of the back surface 6, and then MAX 1120.
Calcination was performed at 13 ° C. for 13 hours to obtain a sample 1.

Example 2 A tile main body 3 similar to the sample 1 was molded and dried, and then baked at MAX 1120 ° C. for 13 hours to obtain a sample 2.

Example 3 A tile main body having an average wall thickness of about 8 mm was formed and dried, and then a glaze 33 was formed on a central portion 34 which is a part of the back surface 6.
And then baked at MAX 1120 ° C. for 13 hours to obtain a sample 3.

Example 4 A roof tile body 3 similar to that of Example 1 was molded and dried, and then fired at MAX 1120 ° C. for 13 hours to obtain a sample 4.

Then, the conventional test piece 5 in which only the above-mentioned test pieces 1 to 4 and the surface were glazed with the same high silver glaze as above was subjected to a bending strength test according to JIS-A5208. Results were obtained.

The bending strength of the test piece 1 was 253 kgf / s, the bending strength of the test piece 2 was 190 kgf / s, the bending strength of the test piece 3 was 177 kgf / s, and the bending strength of the test piece 4 was 110 kgf / s. Bending strength of 219kgf / s becomes glaze like this
33 was found to increase strength.

[0093]

In summary, according to the present invention, since the peripheral portion 12 on the back surface 6 of the roof tile body 3 is left with a predetermined width to form the depression 13, it is possible to prevent damage from the periphery of the roof tile body 3. The bending strength can be maintained at a strength reduction rate smaller than the weight reduction rate, and sufficient practical strength can be provided.

Further, the peripheral portion 12 on the back surface 6 of the roof tile body 3 having the peak portion 1 and the valley portion 2 is left with a predetermined width, and a groove portion having a V-shaped cross section is formed inward of the peripheral portion 12 in the lateral direction. twenty four,
Since a large number of parallel grooves 24a are provided, the groove portions 24, 24a have a V-shaped cross section, so that the compression density during press molding becomes uniform, and the surface 9 has a conventional depression g. Without lowering the commercial value, it is possible to maintain a strength reduction rate that is smaller than the weight reduction rate and to have sufficient practical strength.

In addition, the peripheral portion 12 on the back surface 6 of the roof tile body 3
Is left for a predetermined width, and a large number of first concave portions 25, 25a having a pyramidal bottom portion are engraved inside the peripheral portion 12 to form a honeycomb-shaped rib 26. 25, 25a ...
Since the bottom side of the has a pyramidal shape, the compression density during press molding becomes uniform, so that it is possible to prevent a decrease in commercial value in the same way as above, and to maintain a strength reduction rate that is smaller than the weight reduction rate. The strength of the honeycomb-shaped ribs 26 can be obtained according to the theoretical value, and thus sufficient practical strength can be provided.

Further, the peripheral portion 12 on the back surface 6 of the roof tile body 3
To a predetermined width, and inside the peripheral portion 12, a large number of second recesses 30, 30a having a flat bottom portion are formed by engraving to form ribs 26 of honeycomb shape or the like on one surface 9. Since the concave and convex pattern 31 is appropriately formed, a depression g is generated on the surface 9 at the time of molding due to the second concave portions 30, 30a, ... However, since the depression 31 is covered with the pattern 31, the reduction of the commercial value is prevented. Can be done.

In addition, the peripheral portion 12 on the back surface 6 of the roof tile body 3
To a predetermined width, and inside the peripheral portion 12, a large number of second recesses 30, 30a having a flat bottom side are formed by engraving to form ribs 26 of honeycomb shape and the like, and one surface of which is granular. Since a glaze containing a mixture of alumina, silica sand, etc. was applied and then baked at a temperature at which alumina, silica sand, etc. did not dissolve, a pit g is generated on the surface 9 during molding in the same manner as above, but the pit g Is a convex part made of granular alumina, silica sand, etc.
Since it is covered by 32, it is possible to prevent a decrease in product value.

Also, a part of the back surface 6 of the roof tile body 3 is formed to have a small thickness, and after that, a glaze 33 having a lower melting point than that of the roof tile body 3 is applied to at least a part of the back surface 950 ° C. to 1300 ° C.
Since the degree of sintering of the surface layer portion 35 of the base material was made to progress from the base layer portion 36 by firing at ℃, even if the shape such as cracks, cracks and the like inevitably occur, the surface layer portion 35 and the glaze 33 By fusing and sintering to form a sintered layer 37 having a predetermined thickness, the glaze 33 penetrates into the cracks and cracks and acts as a binder so that there is no reduction in strength due to cracks or cracks. In addition to achieving theoretical strength and increasing the apparent thickness of the sintered layer 37, the roof tiles should be lighter in weight and comparable in strength to conventional products. The practical effect is extremely great.

[Brief description of drawings]

FIG. 1 is a front view of a lightweight roof tile according to claim 1 of the present invention.

FIG. 2 is a rear view of the same lightweight roof tile.

FIG. 3 is a left side view of the same lightweight roof tile.

FIG. 4 is a right side view of the same lightweight roof tile.

FIG. 5 is a bottom view of the same lightweight roof tile.

FIG. 6 is a plan view of the same lightweight roof tile.

7 is a cross-sectional view taken along the line AA of FIG.

8 is a sectional view taken along line BB in FIG.

FIG. 9 is a front view of a lightweight roof tile according to another embodiment of claim 1 of the present invention.

FIG. 10 is a rear view of the same lightweight roof tile.

FIG. 11 is a left side view of the same lightweight roof tile.

FIG. 12 is a right side view of the same lightweight roof tile.

FIG. 13 is a bottom view of the same lightweight roof tile.

FIG. 14 is a plan view of the same lightweight roof tile.

15 is a sectional view taken along line CC of FIG.

16 is a cross-sectional view taken along line DD of FIG.

FIG. 17 is a front view of the lightweight roof tile of claim 2 according to the present invention.

FIG. 18 is a rear view of the same lightweight roof tile.

FIG. 19 is a left side view of the same lightweight roof tile.

FIG. 20 is a right side view of the same lightweight roof tile.

FIG. 21 is a bottom view of the above lightweight roof tile.

FIG. 22 is a plan view of the above lightweight roof tile.

23 is a sectional view taken along line EE in FIG.

FIG. 24 is a sectional view taken along line FF in FIG.

FIG. 25 is a sectional view of another embodiment of the above lightweight roof tile.

FIG. 26 is a front view of a lightweight roof tile according to another embodiment of claim 2 of the present invention.

FIG. 27 is a rear view of the above lightweight roof tile.

FIG. 28 is a left side view of the above lightweight roof tile.

FIG. 29 is a right side view of the above lightweight roof tile.

FIG. 30 is a bottom view of the above lightweight roof tile.

FIG. 31 is a plan view of the above lightweight roof tile.

32 is a sectional view taken along line GG of FIG.

FIG. 33 is a sectional view taken along line HH of FIG. 26.

FIG. 34 is a cross-sectional view of another embodiment of the same lightweight roof tile.

FIG. 35 is a front view of the lightweight roof tile of claim 3 according to the present invention.

FIG. 36 is a rear view of the above lightweight roof tile.

FIG. 37 is a left side view of the above lightweight roof tile.

FIG. 38 is a right side view of the above lightweight roof tile.

FIG. 39 is a bottom view of the above lightweight roof tile.

FIG. 40 is a plan view of the above lightweight roof tile.

41 is a cross-sectional view taken along the line I-I of FIG. 35.

42 is a sectional view taken along line JJ of FIG. 35.

43 is a front view of a lightweight roof tile according to another embodiment of claim 3 of the present invention. FIG.

FIG. 44 is a rear view of the above lightweight roof tile.

FIG. 45 is a left side view of the above lightweight roof tile.

FIG. 46 is a right side view of the above lightweight roof tile.

FIG. 47 is a bottom view of the above lightweight roof tile.

FIG. 48 is a plan view of the above lightweight roof tile.

FIG. 49 is a sectional view taken along the line KK in FIG. 43.

50 is a sectional view taken along line LL in FIG. 43.

FIG. 51 is a front view of a lightweight roof tile according to another embodiment of claim 3 of the present invention.

FIG. 52 is a rear view of the above lightweight roof tile.

FIG. 53 is a left side view of the above lightweight roof tile.

FIG. 54 is a right side view of the same lightweight roof tile.

FIG. 55 is a bottom view of the above lightweight roof tile.

FIG. 56 is a plan view of the above lightweight roof tile.

57 is a sectional view taken along line MM in FIG. 51.

FIG. 58 is a sectional view taken along line NN of FIG. 51.

FIG. 59 is a partial cross-sectional view of the lightweight roof tile according to claim 2 during press molding.

FIG. 60 is a rear view of the lightweight roof tile according to claim 4;

61 is an OO end view of FIG. 60. FIG.

62 is an end view of the lightweight roof tile according to claim 5; FIG.

FIG. 63 is a rear view of the lightweight roof tile according to claim 6;

FIG. 64 is a partial cross-sectional view of the same lightweight roof tile.

FIG. 65 is a partial cross-sectional view at the time of press molding when forming the first recess and the second recess.

FIG. 66 is a schematic plan view of a state in which a lightweight roof tile is installed.

FIG. 67 is a partial cross-sectional view showing a defect in the conventional lightweight roof tile.

[Explanation of symbols]

 1 mountain part 2 valley part 3 roof tile body 12 peripheral part 13 depression part 24, 24a… groove part 25, 25a… first recess 26 rib 30, 30a… second recess 31 pattern 33 glaze 35 surface layer 36 base layer

Claims (6)

[Claims] 1. A lightweight roof tile in which a peripheral portion of the back surface of the roof tile body is left with a predetermined width to form a recess. 2. A peripheral portion of the back surface of the roof tile body having a peak portion and a valley portion is left with a predetermined width, and the inside portion of the peripheral portion is
A lightweight roof tile having a large number of V-shaped groove portions provided in parallel across the lateral direction. 3. A honeycomb-shaped rib or the like is formed by leaving a peripheral portion on the back surface of the roof tile main body for a predetermined width, and engraving a plurality of first concave portions having a pyramidal bottom side inside the peripheral portion. A lightweight roof tile characterized by doing. 4. A rib of honeycomb shape or the like is formed by leaving a peripheral portion on the back surface of the roof tile main body for a predetermined width, and engraving a plurality of second concave portions having a flat bottom side inside the peripheral portion. On the other hand, a lightweight roof tile having an uneven pattern formed on one surface thereof. 5. A rib of honeycomb shape or the like is formed by leaving a peripheral portion on the back surface of the roof tile body with a predetermined width, and engraving a plurality of second concave portions having a flat bottom side inside the peripheral portion. On the other hand, the lightweight roof tile is characterized in that the surface thereof is coated with a glaze in which granular alumina, silica sand, etc. are mixed, and then baked at a temperature at which alumina, silica sand, etc. does not dissolve. 6. A roof layer is formed by forming a part of the back surface of the roof tile body with a thin wall thickness, and then applying a glaze having a melting point lower than that of the roof tile body to at least a part of the back surface and then firing at 950 ° C. to 1300 ° C. A method for manufacturing a lightweight roof tile, characterized in that the degree of sintering of the part is advanced from the base layer part.