JPS58122809A - Method of cutting concrete extruding shape - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for cutting concrete extrusion molded products.

BACKGROUND ART Continuous roll extrusion, which has good productivity, has conventionally been commonly used as a method for forming concrete products such as roof tiles.

Then, in order to make the molded product into a predetermined size, the extrusion molded product in an uncured state immediately after roll extrusion molding is cut with a cutting blade.

By the way, in addition to cement, the forming material (concrete) for concrete products such as tiles is mixed with aggregates such as large-grained river sand and crushed stones with a particle size of 1, Off or larger, for the purpose of generating strength and alleviating shrinkage and expansion stress. has been done.

Therefore, when cutting a molded product with a cutting blade as described above, large-sized aggregate hits the cutting blade and moves as the cutting blade descends, leaving traces of movement on the cut surface. The cut surface was extremely uneven and had cavities, resulting in an extremely poor appearance. In particular, the draining foot 2 on the eaves side of the roof tile 1 (Fig. 1).

(Fig. 2) and the tile hook part 8 have a lower specific gravity than other parts due to roll extrusion molding, and the specific gravity further decreases due to the movement of aggregate during cutting, resulting in a decrease in strength. 2 and the hook portion 3 tend to come off and corners are easily chipped.

This invention was made in view of these circumstances, and involves cutting a concrete extrusion molded product formed by a lower die, corresponding rolls, and forming die with a first cutting blade; The second blade is thicker than the cutting blade.
The gist of this method is to lower the cutting blade onto the cutting portion and press the cut surface to finish the cutting.

That is, in this invention, after cutting the concrete extrusion molded product with a first cutting blade with a thin blade, a second cutting blade with a thick blade is lowered onto the cut portion, so that the cut surface is pressed and beautiful. As the pressure increases, a pressing force is applied to the area near the cut portion, and the specific gravity of that area increases. Therefore, the draining foot and the hook formed by the portion near the cut portion become dense, and the occurrence of corner chips, cracks, etc., is prevented.

Next, the present invention will be explained based on one example.

FIG. 3 is a block diagram of an example of the present invention. In the figure,
The plurality of pallets 4 are arranged to move in the direction of the arrow while maintaining a predetermined interval. 5 is a lower mold placed on the pallet 4.

The forming die 6 is provided so as to face the lower mold 5, and molding material (conc IJ-) flows from the popper 7 onto the lower mold 5 and is fed by the movement of the lower mold 5 and the rotational force of the roll 80. ) 9 is compacted to form an extruded product lO
It has the effect of becoming Reference numeral 11 denotes a first cutting blade with a thin blade for cutting the extrusion molded product IO into dimensions for each lower die 5, and is driven by an air cylinder (not shown). 12 is a molded product I when cut by the first cutting blade 11.
The first step is to prevent the surface from swelling near the cut portion of the O.
It is a pressure. Reference numeral 13 denotes a thick second cutting blade that descends onto the cut portion of the molded product 10 cut by the first cutting blade 11 and presses the cut surface to smooth out the rough cut surface due to movement of the aggregate. do. 14 is a second presser. To explain in more detail, the first cutting blade 11, as shown in FIG.
It descends between the lower molds 5 to cut the molded product 10, forming draining legs tQa on one lower mold 5 side and forming hook portions 10b on the other lower mold 5911. This 7
The cut surface 10C made by the first cutting blade 11 is roughened due to the movement of the aggregate, as shown in FIG. Second
As described above, the cutting blade 1B has a thick blade overall, and the blade thickness at the root of the blade increases rapidly, creating a concave curved surface at the root, and as shown in FIG. 1 cutting blade 1
1, and presses the cut surface toe to make it smooth, and at the curved surface of the root, the draining foot 10a and the hook 10 formed by cutting.
Press the upper corner of the end face of b to give it a rounded shape. In this way, by lowering the second cutting blade 13, the cutting surface 10C is smoothed as shown in FIG. Become.

Moreover, the pressure by the second cutting blade 13 makes the specific gravity of the drainer foot 10λ and the hook portion 10b even, thereby preventing corner chips and cracks from occurring.

Note that the blade thickness of the first cutting blade 11 may be any thickness that can cut the molded product 10, but for example, as shown in FIG. Set to Off.

If it is less than 2.0f1, it will not be durable and will bend easily, and if it is 6.0
If it exceeds the cod, it becomes difficult to cut, and an air cylinder with a very large capacity is required to lower the cutting blade 11. [3 is 0.5-1. It is set to about Off.

Also, [2 is set to (L+ -ts)/2. The blade thickness of the second cutting blade (Fig. 9) 18 is '4v'.
6 e '6 is set to be thicker than the blade thickness '1 e [2 m '3 of the corresponding first cutting blade 11, respectively.

The radius of the curved surface portion at the base is set to a value that can be pressed by the pressing force of the air cylinder.

For example, k is set to 2.0 to 20 cods. That is,
This is because when k is less than 2.0-, the effect is small, and on the other hand, when it exceeds 2011M, it becomes difficult to suppress.

In the above example, the second cutting blade 13 having a curved part at the base is used, but if the blade is thicker than the first cutting blade 11, a blade without a curved part can be used. Good too.

Since this invention cuts a concrete extrusion molded product in the manner described above, it is possible to make the cut surface beautiful, and also prevent the occurrence of corner chips and cracks in the draining feet and hooks that are located near the cutting part. Be able to do it.

Next, examples will be described.

[Example 1] 100 parts of ordinary Portland cement (weight, same below)
800 parts of river sand with a grain size of 2.5 a or less and 45 parts of water were kneaded for 20 minutes to form concrete, which was extruded using an apparatus as shown in FIG. 3 and cut. In this case, the first cutting blade 11 has a blade thickness of 1. 5. QK
M, 12 is 3. QM, tB is 1. Off, and as the second cutting blade 18, the blade thickness [4 is lQ, 9111g, tB is 4.51EI
, t6 of l, 0+g was used. Next, the above cut product was cured to obtain a roof tile.

[Example 2] The first cutting blade 11 has a blade thickness t+ of 5. Q I@,
t2 is 3. Q tM , 13 is 1, OTIIM is used, and the second cutting blade 18 is blade thickness [4 is 2].
0.0''*'s is 8.0M.

[6 or 1. An OB with k of 15 m was used. Other than that, a tile was obtained in the same manner as in Example 1.

[Comparative example]

Cutting is performed only with the first cutting blade 11, and the second cutting blade 1
8 was not used. Other than that, a tile was obtained in the same manner as in Example 1.

The appearance of the cut surface of the tiles obtained in the above Examples and Comparative Examples and the specific gravity of the draining feet and hooks were investigated. The results are shown in the table below. From the table, it can be seen that the example products have a good appearance on the cut surface, and the draining feet and the tile hooks are dense.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a roof tile obtained by the conventional example, Fig. 2 is a cut-away view taken along line A-A', Fig. 8 is a detailed explanatory view of the present invention, and Fig. 4 is an extrusion molded product of the first type. An explanatory diagram of the state of cutting by the cutting blade, FIG. 5 is an explanatory diagram of the state after cutting,
Figure 6 is an explanatory diagram of the state in which the second cutting blade is lowered into the cutting section, Figure 7 is an explanatory diagram of the state after processing by the second cutting blade, and Figure 8 is the dimensions of the first cutting blade. Explanatory diagram explaining, No. 9
The figure is an explanatory diagram illustrating the dimensions of the second cutting blade. 5... Lower die 6... Forming die 7... Hopper 8... Roll 9... Molding material 10...
・Extrusion molded product 10C... Cutting surface 11... First cutting blade 13... Second cutting blade Patent applicant Matsushita Electric Works Co., Ltd. Agent Patent attorney Takehiko Matsumoto Figure 6 Figure 8 Figure 7 No. 91〈

Claims (1)

[Claims] CI) A concrete extrusion molded product formed by a lower die and corresponding rolls and a forming die is cut with a first cutting blade, and then the concrete extrusion molded product is cut with a blade thicker than the first cutting blade. A method for cutting a concrete extrusion molded product, characterized in that a second cutting blade is lowered to the cutting portion and the cut surface is pressed and finished. (2) Cutting of a concrete extrusion molded product according to claim 1, wherein the second cutting blade has a root portion that is rapidly thickened and has a concave curved surface portion formed at the root portion. Method. (3) The method for cutting a concrete extrusion molded product according to claim 1 or 2, wherein the concrete extrusion molded product is a concrete extrusion molded product for roof tiles.