JPH0626803B2 - Molding method for tiles with legs - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for forming a tiled tile formed with a pair of legs protruding from the back surface of a flat plate-shaped tile body.

(Problems to be Solved by Prior Art and Invention) Conventionally, it has been practiced to mount a ferrite-based molded body on a wall of a building such as a high-rise building to absorb radio waves. This is to prevent radio waves from TVs, radios, etc. from being reflected by skyscrapers and causing radio interference to surrounding private houses.

However, in this case, the ferrite-based compact may be separated from the concrete forming the wall of the building due to expansion and contraction due to temperature changes and the like. Therefore, the applicant of the present invention, in the previous patent application (Japanese Patent Application No. 60-284372),
It was proposed to mount the ferrite-based compact on the wall of the building using tiles with legs. According to the present invention, a ferrite-based molded body is fixed on the back surface between the legs of the tile, and in that state, the tile and the concrete are integrated by placing concrete from the back side of the tile, thereby making it possible to absorb electromagnetic waves. It is designed to form a wall.

By doing this, the legs of the tile are digging into the concrete, the tile is firmly fixed to the concrete, and the ferrite molded body is held between the legs of the tile and the legs, It will be embedded inside the wall, and the ferrite molded body will not come off even when the temperature changes. Along with this, the legs of the tiles act as spacers to keep the distance between the reinforced mesh inside the concrete and the ferrite molded body constant, so that the radio waves reflected by this reinforced mesh are well absorbed by the ferrite molded body. become.

By the way, if this tile with legs is formed by a usual method, a protrusion is formed on the back surface between the legs, which causes a difficult problem that the function as the tile for the electromagnetic wave absorbing wall is deteriorated.

In order to explain the reason, a normal forming method of the tile with seed legs will be described with reference to FIGS. 5 to 8.

In these figures, 100 is an extruder, 102,
Reference numeral 104 is a cylinder attached to the tip of the cylinder, and 106 is a molding die, which is attached to the tip of the cylinder 104 by a frame 108 and bolts 110. In addition, 107 in FIGS. 5 and 7 is a middle die forming a part of the molding die 106. As shown in FIG. 6, the molding die 106 has a space in which two legged tiles are combined on the back side. That is, the molding die 106 has two cavities 112, 112 corresponding to the flat plate-shaped tile body and two cavities 114, 114, 114, 11 corresponding to each pair of legs.
4 and also a joining cavity 116 for joining these two tiles. Then, when the base material from the extruder 100 is extruded through the empty space of the molding die 106, a molded body in a form in which two tiles with legs are combined is obtained.
After that, the molded body is cut into a predetermined length, and after firing, as shown in FIG.
They are forcibly separated from each other at the notch 122 formed at the base portion of 20.

At this time, as shown in FIG. 9, on the back surface of the tile, the burrs 15 in which the joints 120 are forcibly removed have irregular projections 15 are formed.
The protrusion-shaped burr 150 becomes 0 and remains as an obstacle when the ferrite-based compact is fixed to the back surface of the tile. That is, due to the presence of the burr 150, the ferrite-based compact is not firmly adhered to the back surface of the tile, so that the distance between the ferrite-based compact and the rebar mesh is not constant, and the electromagnetic absorption of the ferrite-based compact is absent. The function deteriorates.

(Means for Solving Problems) The tile forming method of the present invention has been devised to solve such problems, and the gist thereof is a flat plate-shaped tile main body and the tile main body. Is a method of forming a legged tile having a pair of legs projecting on the back surface in the vicinity of both ends of the base material, wherein the base material passes through a single space having a shape corresponding to the tile body, A pair of legs correspond to each of them, and each of them has a space which is longer than the legs by a certain amount, and a molding die having a molding surface having a shape corresponding to one of the legged tiles. Attached to the extrusion die, and extruding the base material from the extruder through the cavity of the molding die, and extruded from the die by a thin wire stretched across the cavity corresponding to the leg of the molding die. The leg tips of It is to excise a certain amount.

(Operation) The present invention is characterized in that a pair of legs with a pair of legs protruding from the back surface of a flat plate-shaped tile body is formed as a single unit, not in the conventional two-layered tile.

A difficult problem in single-molding such a legged tile is that when a base material is extrusion-molded through a cavity of a molding die, the molded body warps toward the leg.

Behavior of the base material inside the extruder, flow resistance when the base material passes through the molding die attached to the end of the extruder, when the base material is extruded continuously in a long shape and wet-formed into tiles, the base material It is a well-known fact that the factors such as the degree of compression have a significant influence on the deformation of the molded body or the uniformity of subsequent shrinkage such as drying and firing.

However, the behavior of the base material inside the extruder and the flow behavior of the base material when passing through the forming die are extremely complicated, and accurate control thereof is difficult.

Therefore, in general, when the tile is wet-extruded, it is a principle to extrude the tile so that the shape of the formed body is symmetrical to the left and right and up and down. When extrusion molding is performed in a symmetrical shape in the left-right direction and in the vertical direction, the flow resistance of the base material when passing through the forming surface of the forming die, the degree of compression with respect to the base material, and the like are equalized in the left-right direction and the top-bottom direction. Can be prevented.

It is based on such a circumstance that the legged tiles are formed in a combined state as shown in FIGS. 5 to 6.

However, as described above, when the two tiles with legs are formed in a combined state, there is a problem that the burr 150 is finally generated on the back surface.

Therefore, in the present invention, the legged tile is extruded by itself, and at that time, the leg is formed longer than the leg of the actual product, and at the same time as the forming, an extra length portion is formed with a thin wire. I decided to remove it. It has been confirmed that this makes it possible to prevent the warping deformation even when the legged tile is molded alone, and the reason is considered to be as follows.

That is, when the legged tile is molded by itself, a large amount of flow resistance is exerted on the base material when the base material comes into contact with and passes through the forming surface corresponding to the leg tip of the forming die. When passing through the die, it tends to be pulled relatively to the rear side, and the compressibility and flow behavior of the base material in the same part are greatly different from other parts, which causes the molded body to warp to the leg side. It is considered to cause the phenomenon.

However, if the legs are made longer than the product and the tips are cut off at the same time as molding with thin wires, the parts that cause warpage deformation are removed, and the thin wires during molding also cause the tips of the legs and other parts to be removed. It is considered that the edges are cut off to prevent the large flow resistance acting on the leg tips from propagating to other parts, and as a result, the legged tile is favorably molded.

At this time, that is, if a cutter that creates a large flow resistance when cutting off the leg tips is used, a large new flow is added to the tip of the remaining leg that has been cut, that is, the leg that is actually the product. This causes resistance, and also changes such as increasing the degree of compression of the base material of the same portion, so that the meaning of lengthening the leg and cutting off the tip portion is diminished.

This is the reason why the thin wire is used for cutting the leg tip portion in the present invention.

Now, when the legged tile is formed according to the method of the present invention,
No burrs remain on the backside between the tile legs. In this forming method, the tiles are not extruded together but extruded as a single piece. Therefore, the above-mentioned joining portion for joining each of the two-tile tiles is not necessary, and therefore the tiles are separated. There is no need to remove it, and no burr will occur after that.

Thus, since the back surface of the tile with legs molded in this way is smooth, if a radio wave absorber such as a ferrite molded body is fixed to the back surface between these legs, the radio wave absorption The body adheres well to the back. As a result, the distance between the radio wave absorber and the rebar mesh is kept constant, and the radio wave reflected by the rebar mesh is well absorbed by the radio wave absorber.

(Example) Next, the Example of this invention is described in detail based on drawing.

FIG. 2 shows an example of a legged tile formed according to the present invention. In the figure, reference numeral 12 denotes a flat plate-shaped tile main body in the legged tile 10, and a pair of legs 14, from a position slightly retracted inward from both longitudinal ends thereof,
14 projects to the back side. The back surface 16 between the legs 14 and 14 is a smooth surface without burrs.

FIG. 3 shows the structure in which a wall for absorbing radio waves is constructed using the tile 10 with legs. 18 in the figure
Is a ferrite type molded body as a radio wave absorber, and tile 1
Cement (mortar) 20 is attached to the back surface 16 between the legs 14 of the No. 0. And this tile 1
Since the back surface 16 of No. 0 is a smooth surface without burrs as described above, the entire ferrite-based compact 18 is attached to the back surface 16 of the tile 10 sufficiently closely.
The thickness of the ferrite-based compact 18 is 10 mm here.
~ 20mm, cement thickness is 2m
The height of the leg portion 14 of the tile 10 is 37 mm.

In these tiles 10, the tip of each leg 14 has a rebar mesh 2
The tiles 10 are arranged in a state of being in contact with the tiles 2, and the concrete 24 is cast from the back side thereof,
The ferrite-based molded body 18, the rebar mesh 22, and the concrete 24 are configured as an integral radio wave absorbing wall 25. The radio wave absorbing wall 25 may be constructed by assembling on-site precast concrete plates, or the wall 25 may be constructed by directly pouring concrete on site without using such a method. It may be done.

In the radio wave absorption wall 25 configured as described above, the radio wave coming from the outside is first directly absorbed by the ferrite molded body 18, and the radio wave remaining without being absorbed at that time is reflected by the reinforcing bar mesh 22, It is subsequently absorbed by the ferrite compact 18. At this time, each leg 14 of the tile 10 functions as a spacer that keeps the distance between the ferrite-based molded body 18 and the rebar mesh 22 constant, and thereby enhances the electromagnetic wave absorption performance of the ferrite-based molded body 18. However, if there is a protrusion on the back surface 16 between the legs 14 of the tile 10, the ferrite-based molded body 18 does not adhere to the tile back surface 16, so the ferrite-based molded body 18 and the reinforcing bar mesh 2
The distance from 2 is not constant, and the electromagnetic wave absorption performance of the ferrite-based compact 18 is reduced.

On the other hand, if the back surface 16 between the legs 14 of the tile is made smooth, the ferrite-based molded body 18 as a whole closely adheres to the back surface without any gap, and such a problem does not occur.

Such a tiled tile 10 having a smooth back surface is formed as follows.

In FIG. 1 and FIG. 4, 28 is an extruder,
Reference numerals 0 and 31 denote cylinders attached to the tip thereof, and a molding die 38 is fixed to the cylinder 31 by a frame 32 and bolts 34.

As shown in FIG. 1, the molding die 38 has one cavity 40 whose cavity corresponds to the main body 12 of the tile 10 and the leg 1
It is composed of a pair of cavities 42, 42 respectively corresponding to 4, 4. That is, the molding die 38 is configured so that the tile 10 can be molded in a single state, not in a state where two tiles are combined.

The cavity 40 corresponding to the tile body 12 is formed longer than the tile body 12, and the cavity 42 corresponding to the leg 14 is also formed longer than the leg 14 by a predetermined length. Then, four piano wires (thin wires) 44 and 46 are stretched by pins while crossing the front openings of the cavities 40 and 42.

In this apparatus, when the base material is extruded from the extrusion 28, the base material is molded into a predetermined shape through the cavities 40 and 42 of the molding die 38. At this time, the tip ends of the legs 14 and the both ends of the tile body 12 are fixed by a certain amount.
It is cut by 6, 44 and molded into a molded product having the same size as the tile 10.

By the way, when the tile 10 is simply extruded by itself, a phenomenon occurs in which the tile 10 warps back toward the leg 14. This is because the extrusion speed on the tip side of the leg 14 becomes relatively slow based on the frictional resistance of the mold surface corresponding to the tip surface of the leg 14 of the molding die 38.

In the molding method of this example, in order to prevent this warpage, the void 42 corresponding to the leg 14 of the molding die 38 is lengthened by a certain amount, and the molding base extruded from the void 42 is moved by the piano wire 46. It is designed to cut out only that long amount. Therefore, the portion causing the warp is effectively removed, and the extruded molding base does not warp. In other words, by using such a method, it becomes possible to mold a single tile (if the two tiles are molded as described above, such a problem does not occur). ), Which results in the tile joint 1
No need for 20 and no burr remains on the tile after molding,
The back surface 16 becomes a smooth surface.

In addition, in this example, the tile body 1 is connected by the piano wire 44.
The two ends and the end of the leg 14 are cut off by the piano wire 46, but the purpose is different between the piano wires 44 and 46. That is, in the case of the method of this example, the piano wire 4 is used even though the molded body has a symmetrical shape.
The end of the tile body 12 is cut off at 4 when the end (ear) remains as it is in the drying and firing steps after the tile forming even if no deformation occurs in the forming stage. Since the raw material packing density at the end portion (ear portion) is coarse, the contraction at the same portion is larger than that at the other portion, resulting in variation in shape and size, and therefore this is cut off. The leg ends are cut off in order to prevent the legged tile molded body from warping and deforming during molding as described above. That is, the cutting off of the end portion 12 of the tile body by the piano wire 44 is not directly involved in the purpose of preventing the molded body from being warped and deformed toward the leg 14 when the tile with legs is molded.

Although the embodiments of the present invention have been described above in detail, the present invention can be implemented in other modes.

For example, the shape of the legged tile can be changed variously, and the method of molding the tiled tile can also have various other modes.

(Effects of the Invention) As described in detail above, according to the present invention, the back surface of the legged tile can be easily smoothed while suppressing the shape change during tile forming as low as possible. This makes it possible to enhance the radio wave absorbing function of the radio wave absorber when a wall for absorbing radio waves is formed using such tiles with legs.

[Brief description of drawings]

FIG. 1 is an explanatory view for explaining a tile forming method which is an embodiment of the present invention. FIG. 2 is a perspective view of a tile molded by the molding method of FIG. 1, and FIG.
It is sectional drawing which shows the structure at the time of constructing the wall for electric wave absorption using the tile of the figure. FIG. 4 is a sectional view of an essential part of a molding apparatus for carrying out the tile molding method according to an embodiment of the present invention, and FIGS. 5 and 6 show the legged tile of FIG. 2 by a normal method. It is a principal part sectional view and front view of a molding device used at the time of molding. FIG. 7 is a perspective view of an essential part showing a part of the forming die of FIG. 5, and FIG. 8 is a perspective view of a two-piece laminated tile formed by the forming apparatus of FIGS. 5 and 6. FIG. 9 is a perspective view showing a state of burrs produced when the two-ply tiles of FIG. 8 are forcibly separated one by one. 10: Tile with legs 12: Tile body 14: Legs 16: Back side 38: Molding dies 40, 42: Empty space 44, 46: Piano wire

Claims (1)

[Claims] 1. A method of molding a tiled tile having a flat plate-shaped tile main body and a pair of legs projecting on the back surface in the vicinity of both ends of the tile main body, wherein a void for passing a base material is provided. With one leg having a shape corresponding to the tile body and one cavity corresponding to each of the pair of legs and having a length longer than the legs by a certain amount. A molding die shaped to correspond to the tile is attached to the tip of the extruder to push the green material from the extruder through the cavity in the molding die and across the cavity corresponding to the legs of the molding die. A method for forming a legged tile, characterized in that the tip end portion of the leg of the base material extruded from the die is cut off by a certain amount by the thin wire stretched in this manner.