JPH028884B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method for forming a random uneven pattern on the surface of a tile having a sawtooth uneven surface. (Prior art) Tiles used as exterior materials, etc.
Some have various surface shapes. One example is a tile with a sawtooth-like uneven surface. The method for forming this sawtooth-shaped tile is as follows:
There is an extrusion method in which a molding die having a cavity of a predetermined shape is attached to the tip of an extruder, and the raw material from the extruder is extruded through the die to be formed into a predetermined shape. (Problems to be Solved by the Invention) However, the sawtooth-shaped tiles formed by this extrusion method have a continuous and uniform shape in the extrusion direction due to the forming principle. A sawtooth tile having a uniform cross-sectional shape along the extrusion direction and a random uneven pattern on the surface along the extrusion direction could not conventionally be formed by such an extrusion method. (Means for Solving the Problems) The present invention has been made to solve these problems, and its gist is that a molding die having a cavity for extrusion molding is placed at the tip of an extruder. At the same time, a thin plate having saw blade-shaped sharp molding teeth is attached to the front surface of the molding die, and the plate is oriented substantially perpendicular to the extrusion direction of the extruder, and the molding teeth are positioned at the front end of the molding die cavity. While installing the tile in a state across the opening, a coarse raw material with coarse particles is added to the fine raw material that is the main material of the tile, and the base material containing the coarse raw material is extruded from the extruder through the cavity of the forming die. , the surface of the extruded base material extruded from the molding die is scraped by the molding teeth to form the surface of the molded body into a saw-blade-like uneven shape, and at the same time, the coarse particles present on the surface of the extruded base material are caught by the molding teeth. By this, a random uneven pattern is formed on the saw blade-shaped surface of the molded body. (Operation) In this method, a raw material containing coarse grains is extruded from an extruder through the cavity of a forming die, and at the same time, its surface layer is formed into a sawtooth shape by the forming teeth of a plate. Ru. In other words, the surface of the extruded base material is cut into a saw blade shape by the molded teeth.
At this time, the coarse particles existing on the surface of the extruded base material are caught by the molded teeth and temporarily stop moving, or sink into the interior of the base material. As a result, the portion where the coarse grains were present and the subsequent and neighboring portions of the coarse grains become hollow. Since a large number of such coarse particles exist on the surface of the extruded base material, a large number of such hollow portions are randomly generated when looking at the surface of the molded product as a whole. This hollow portion and the remaining protrusions are randomly intermingled, forming an uneven surface pattern on the sawtooth tile. (Example) Next, an example of the present invention will be described in detail based on the drawings. FIG. 2 shows an example of a tile formed by this method. As shown in the figure, this tile 10 has dovetail feet 12 and dovetail grooves 14 on the back surface, and has a large number of protrusions 16 in the extrusion direction on the front surface, and the entire surface has a saw blade shape. It has an uneven shape. Further, a large number of relatively small concave portions 18 are formed on the surface thereof, and these concave portions 18 and the remaining protrusions form a random concavo-convex pattern. Next, a method of forming such a tile 10 will be explained based on FIG. 1 and FIGS. 3 to 6. In these figures, reference numeral 20 denotes an extruder, with cylinders 22 and 24 fixed to its tip, and cylinders 2
A molding die 26 having a cavity 36 in the form of two tiles 10 put together is attached to the front end surface of 4 by a frame 32 and bolts 34. still,
Inside the cylindrical body 24, a middle mold 28 is disposed, supported by a support 30, and with its tip inserted into a cavity 36. The medium mold 28 is for molding the dovetail legs 12 and the dovetail grooves 14, and has a cross-sectional shape in which the dovetail grooves 14 are stacked one above the other. A pair of plates 38 for forming saw blade surfaces are disposed on the front surface of the die 26 so as to face each other vertically and with the plate surfaces facing in a direction perpendicular to the extrusion direction of the extruder 20. As shown in FIG. 4, the plate 38 is a thin plate-like member, and has a bolt hole 42 in the middle portion in the width direction, and is fastened to the front surface of the die 26 through the bolt hole 42. These plates 38 also have sharp saw-blade-shaped molded teeth 44 along one end in the width direction, and are fixed in a state where the saw-blade-shaped molded teeth 44 cross the front end opening of the cavity 36. ing. Note that this molded tooth 44 is the fifth
As shown in the figure, the rear surface (the surface on the die 26 side) is a steeply inclined surface 46. In order to mold the tile 10 using this molding device, first, raw materials are prepared. The raw material is feldspar 40
~50 wt%, clay is 50-60 wt% as a fine-grained main material, and a coarse-grained material is used as an auxiliary material. As an auxiliary material, for example, 20 pieces of yellow siyamoto (16
The remaining amount when sieved using standard mesh and 32 mesh sieves was 1.5wt% and 28.4wt%, respectively.
(The amount passing through the 32 mesh sieve is 70.3wt%)
Use. The amount of auxiliary material added shall be 20wt% of the auxiliary material to 80wt% of the main material. For 80wt% of the base material adjusted in this way,
20wt% of water is added and kneaded, and this is extruded from the extruder 20. The base material from the extruder 20 is transferred to the cylinder 2
2 and 24, and is extruded outward from the cavity 36 of the die 26 to form a molded body in the form of two tiles 10 put together. At this time, the surface of the extruded material that has passed through the cavity 36 of the die 26 is scraped by the forming teeth 44 of the plate 38, so that the surface is formed into a sawtooth-like uneven shape. At the same time, the large number of concave portions 18 are formed, and a random pattern of concave and convex shapes is formed on the surface of the molded product. The principle is as follows. That is, the surface of the base material extruded from the extruder 20 and passed through the cavity 36 of the die 26 is dotted with many coarse grains added as an auxiliary material, and these coarse grains form the molded teeth 44 of the plate 38. When passing through, it gets caught on the molded teeth 44. The caught coarse particles are stopped moving by the molded teeth for a certain period of time, or sink into the inside of the base material. As a result, the portion where the coarse grains were present and the adjacent portion subsequent thereto are partially hollowed out, and this becomes a recessed portion 18 on the surface of the compact. In this example, the reason why a thin plate is used to form a sawtooth surface and a random uneven surface pattern is as follows.

[Table] First, the table shows the results of tests to form saw blade surfaces and random uneven patterns by varying the thickness of the play 38. As shown in the table, as the plate 38 becomes thicker than a certain thickness, it becomes difficult to obtain good results.
This is because as the thickness of the plate 38 increases, the angle of inclination of the sloped surface 46 on the molded tooth 44 becomes gentler, that is, the molded tooth 44 gradually becomes less sharp, and the coarse particles become less sharp on the molded tooth 44. It is surmised that this is because it becomes difficult to hook onto the 44. It is unknown why good results were not obtained in this test when the thickness of the plate 38 was 2 mm. This test result was obtained when a coarse grain material with a roughness of 20 was used, and if coarse grain materials with different roughnesses are used, the suitable range for the width of the plate 38 will also differ. Generally, it is desirable that the thickness of the plate 38 be 10 mm or less. Although the embodiments of the present invention have been described in detail above, the present invention can be implemented in other embodiments. For example, it is possible to use materials different from those in the above embodiments as the base material, and it is also possible to change the type of coarse grain material added thereto and the coarseness of the particles. Furthermore, the present invention can be applied even when the saw blade surface shape is formed in a shape different from that of the above embodiments, and the plate can also be attached with a slight inclination. It is possible to implement various modifications based on the knowledge of those skilled in the art without departing from the spirit of the invention. (Effects of the Invention) As described above, according to the present invention, a base material containing coarse particles is extruded through a forming die, and the surface layer thereof is shaved with sharp saw blade-like forming teeth. Thereby, the surface of the extrusion molded product can be formed into a sawtooth-like uneven shape, and at the same time, a random uneven surface pattern along the extrusion direction can be formed.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a method of forming a random uneven surface pattern according to an embodiment of the present invention. FIG. 2 is a perspective view of a tile having an uneven surface pattern, and FIG. 3 is a sectional view of a main part showing an apparatus for carrying out the method. FIG. 4 is a perspective view of the plate in FIGS. 1 and 3, and FIG. 5 is a sectional view of a main part of the molded teeth of the plate. FIG. 6 is an enlarged perspective view of the main part of FIG. 1; 10: Tile, 16: Projection, 18: Recess, 2
0: Extruder, 26: Molding die, 36: Void, 3
8: Plate.

Claims (1)

[Claims] 1. A method for forming a random uneven pattern on the surface of a tile having an uneven surface in the form of a sawtooth surface, which comprises: attaching a molding die having a cavity for extrusion to the tip of an extruder; At the front of the forming die, a thin plate having sharp forming teeth in the shape of a saw blade is oriented in a direction substantially perpendicular to the extrusion direction of the extruder, and the forming teeth cross the front end opening of the forming die cavity. While installing the tile in a state in which it is attached, a coarse raw material with coarse particles is added as an auxiliary material to the fine raw material that is the main material of the tile, and the base material containing the coarse raw material is extruded from the extruder through the cavity of the forming die. , the surface of the extruded base material extruded from the molding die is scraped by the molding teeth to form the surface of the molded body into a saw-blade-like uneven shape, and at the same time, the coarse particles present on the surface of the extruded base material are caught by the molding teeth. 1. A method for forming a random uneven surface pattern on a sawtooth tile, the method comprising: forming a random unevenness pattern on the sawtooth surface of a molded article.