JPH09277224A - Forming device of hydraulic inorganic formed matter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the forming device of hydraulic inorganic formed matter, which has a uniform specific gravity and strength and, needless to say, with which a dense and high strength formed matter can be obtained without making the structure of the forming device more complicated. SOLUTION: In the forming device 1a, in which a hydraulic inorganic forming material is forced in a cavity formed by closing a top and a bottom molds 2 and 3 together and then shaped in the desired shape by vacuum-dehydrating the excess water content in the hydraulic inorganic forming material through drainage holes 21 bored on the molding surface of the bottom mold 2, by changing the thicknesses of a portion 51 abutting against the lower edge face 31a of the projecting part 31 of the top mold 3 and of a portion 52 abutting against its projecting part 31b of an elastic sheet 5, the pressures applying to the hydraulic inorganic forming material are made equal to each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding device for a hydraulic inorganic molded product.

[0002]

2. Description of the Related Art Conventionally, a molding apparatus as disclosed in Japanese Examined Patent Publication No. 59-37203 has been used for manufacturing a hydraulic inorganic molding. That is, as shown in FIG. 4, such a molding apparatus 100 is composed of an upper mold 101 which is one split mold, and another split mold which is provided with a filter cloth 103 made of a stretchable material so as to cover the mold surface. There is a lower mold 10
The hydraulic inorganic molding material 104 is injected from the upper mold 101 side into the mold cavity formed by closing 2 to fill the filter cloth 103 while extending it along the mold surface of the lower mold 102, and Excessive water content in the hydraulic inorganic molding material 104 is sucked and dehydrated through the filter cloth 103 through a large number of water drain holes 105 formed in the mold surface of the mold 102 to obtain a hydraulic inorganic molded body. There is.

[0003]

However, in the molding apparatus as described above, only the suction dehydration from the water drain hole 105 is performed, and no pressure is applied to the molding material in the mold cavity.
The obtained molded product has a problem that it lacks in denseness and is weak in strength. Therefore, the inventor of the present invention provides a rubber elastic sheet (elastic contraction body) 203 along the mold surface 202 of the upper mold 201 as shown in FIG.
After press-fitting into the mold cavity, excess water is sucked and dehydrated from the drain hole 207 of the lower mold 205, and a pressurizing medium such as water or air is pressed between the elastic sheet 203 and the mold surface 202 of the upper mold 201. Then, a molding apparatus 200 has been already proposed in which the elastic sheet 203 is bulged toward the mold surface 208 of the lower mold 205 to apply pressure to the molding material in the mold cavity to achieve densification (Japanese Patent Laid-Open No. Hei 10 (1999) -242242). 5-200709). In addition,
Reference numeral 206 in the figure denotes a pressurizing medium press-fitting hole.

That is, since the molding apparatus 200 can apply a sufficient pressure to the molding material in the mold cavity by the bulging of the elastic sheet 203, most of the above problems can be solved. However, for example, when it is attempted to obtain a molded body in which the mold cavity has a substantially concave cross section as shown in FIG. 5, a pressurizing medium is press-fitted to bulge the elastic sheet 203 and the molding material in the mold cavity is expanded. When pressure is applied to the elastic sheet 203, a difference in water pressure occurs between the portion corresponding to the bottom surface of the mold cavity and the portion corresponding to the side surface rising from the bottom surface.
The swelling rate of is slightly different.

Therefore, as a result, the compressibility of the molding material is different between the bottom surface portion and the side surface portion of the mold cavity, and there is a possibility that the finished hydraulic inorganic molding material partially has a difference in specific gravity and strength. In the vicinity of the pressurizing medium press-fitting hole 206,
The swelling rate of the elastic sheet 203 is slightly different between the pressurizing medium press-fitting hole 206 and the intermediate portion between the pressurizing medium press-fitting hole 206. Therefore, the compressibility of the molding material corresponds to the above-mentioned swelling of the elastic sheet 203. However, there is a possibility that the resulting hydraulic inorganic molded article may partially differ in specific gravity and strength.

Therefore, as a method for solving the above problems,
It is conceivable to narrow the pitch of the pressurizing medium press-fitting holes 206. However, if the pitch is narrowed, the number of pressurizing medium press-fitting holes 206 must be increased, and if the number of pressurizing medium press-fitting holes 206 is increased, the die surface 202 of the upper die 201 is increased.
However, the strength of the mold becomes weaker, and there is a risk that sufficient pressure cannot be applied to the molding material.

On the other hand, it is considered that the above-mentioned problems with the hydraulic inorganic molded article can be solved by bulging the elastic sheet 203 in a moment by applying a strong pressure at once. In this case, since the load on the elastic sheet 203 becomes large, it is difficult to control the pressure so as not to damage the elastic sheet 203, and the structure of the molding apparatus itself becomes considerably complicated.

In view of such circumstances, the present invention can obtain a dense and high-strength molded product without making the structure of the molding device complicated, and of course, it has a uniform specific gravity and strength. It is an object of the present invention to provide a molding apparatus for a hydraulic inorganic molded article having the above.

[0009]

In order to achieve such an object, a hydraulic inorganic molded article molding apparatus according to the invention of claim 1 (hereinafter referred to as "apparatus of claim 1").
Is a first split mold in which a large number of water drain holes are formed along the mold surface, and a second split mold in which the mold surface is covered with an airtight elastic sheet whose periphery is hermetically sealed. Press the hydraulic inorganic molding material into the mold cavity formed by closing,
Excess water in the hydraulic inorganic molding material is sucked and dehydrated from a water draining hole formed in the mold surface of the first split mold to form a desired shape, and the elastic sheet and the mold surface of the second split mold are also formed. A molding device for a hydraulic inorganic molded article, in which a pressurizing medium is pressed between the elastic sheet and the first split mold to swell the compressed hydraulic inorganic molding material through the elastic sheet. In the elastic sheet, a thick portion thicker than the other portion is provided in a portion where the press-fitting pressure of the pressurizing medium is high, in order to equalize the bulging rate with the other portion. It has a structure.

Further, a hydraulic inorganic molded article molding apparatus according to the invention of claim 2 (hereinafter referred to as "apparatus of claim 2").
Refers to a first split mold in which a large number of water drain holes are formed along the mold surface, and a second split mold in which the mold surface is covered with an airtight elastic sheet whose periphery is hermetically sealed. The hydraulic inorganic molding material is press-fitted into the mold cavity formed by closing the mold, and excess water in the hydraulic inorganic molding material is sucked and dehydrated through the water drain holes formed in the wall surface of the first split mold. Then, the elastic sheet is bulged toward the first split mold side by press-fitting a pressurizing medium between the elastic sheet and the mold surface of the second split mold, through the elastic sheet. In a molding device for a hydraulic inorganic molding material configured to compress a hydraulic inorganic molding material, a mold surface of the second split mold is provided between the elastic sheet that is opened and the mold surface of the second split mold. There are many pressurizing medium press-fitting holes for pressurizing the pressurizing medium. And a configuration in which adjacent perforations is connected through a groove provided along the mold surface of the second split mold of.

In the structure of the apparatus of the above-mentioned claim 1 and claim 2, the pressurizing medium is not particularly limited, but liquids such as water and oil can be mentioned. The elastic sheet is not particularly limited, and examples thereof include materials having excellent airtightness and watertightness such as rubber and plastic.

The hydraulic inorganic molding material is mainly composed of a hydraulic inorganic material which is hardened by a hydration reaction such as cement, gypsum and calcium silicate forming material. In addition to the main component, aggregates such as sand and gravel. , Glass fibers, animal and vegetable fibers, synthetic fibers, semi-synthetic fibers, and other reinforcing materials, rapid hardening materials, pigments, and the like, and a mixture of materials that can be used in the production of general inorganic molded articles.

The compression and the suction may be performed at the same time, but it is preferable that the suction is first performed and the compression is started after a lapse of a predetermined time. The injection pressure of the hydraulic inorganic molding ^{materials, 3kg / cm 2 ~70kg / cm} 2 is preferably about. That is, if it is less than 3 kg / cm ² , molding may be possible but a dense molded product may not be obtained, and if it exceeds 70 kg / cm ² , the raw material injection pipe may be clogged with raw material.

The suction and dehydration pressure from the water drainage hole is preferably about -500 mmHg to -700 mmHg. That is, if the pressure is higher than -500 mmHg, the excess moisture in the molding material cannot be sufficiently dehydrated. If the pressure is lower than -700 mmHg, the degree of vacuum is too high and the material may be clogged during dehydration. Furthermore, the injection pressure of the pressurized medium between the elastic sheet and the mold surface of the second split mold is 10 kg.
/ Cm ^{2 to} 90 kg / cm ² is preferable. That is, 10
If it is less than kg / cm ² , the effect of densifying the shaped article is not seen, and if it is more than 90 kg / cm ² , the elastic sheet may be damaged.

In the molding apparatus of the present invention, when the hydraulic inorganic molding material is pressed into the mold cavity, the stretchable filter cloth extending along the mold surface of the first split mold into the first split mold. It is preferable to provide them integrally. The material of the elastic filter cloth is not particularly limited as long as it is a material whose dimensions expand when the external force is applied and which has water permeability and is, for example, a cloth using crimped yarn, a porous material. Examples thereof include rubber and stretchable acrylic fiber.

In the structure of the apparatus according to the first aspect, a portion of the elastic sheet where the pressurizing pressure of the pressurizing medium is high is a thick portion, and a difference in thickness between the thin portion which is another portion is a pressure difference. For example, when trying to obtain a molded product with a substantially concave cross-section, the thick part is the part that is in close contact with the concave bottom part where high pressure is applied, and the concave rising part that only applies relatively low pressure. It is preferable that the portion that is in close contact with is thin and that the thickness of the thick portion is 2 to 3 times the thickness of the thin portion.

In the structure of the apparatus of claim 2, the width and depth of the groove are not particularly limited, but the width is about 1 mm to 5 mm,
The depth is preferably about 1 mm to 3 mm. That is, if the width is too narrow or the depth is too shallow, the effect of providing the groove does not appear, and if the width is too wide or the depth is too deep, the elastic body may enter the groove and be damaged by the edge of the groove. is there.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below.
This will be described in detail with reference to the drawings. FIG. 1 shows claim 1.
2 shows an embodiment of the molding apparatus of FIG. As shown in FIG. 1, the molding apparatus 1a includes a lower mold 2 which is a first split mold.
And an upper mold 3 which is a second split mold, a filter cloth 4, and an elastic sheet 5.

The lower die 2 has a die surface 20 having a substantially downward cross section, and a large number of drain holes 21 are formed in the die surface 20.

The upper mold 3 has a convex portion 31 facing the raised portion of the lower mold 2, and the pressurized medium buffer tank 3 is provided in the convex portion 31.
2 is provided, and a pressurizing medium press-fitting hole 33 communicating with the pressurizing medium buffer tank 32 is opened in the mold surface 30. Further, as will be described later in detail, the mold surface 30 has an injection port 7 of a pipe 7 for injecting the hydraulic inorganic molding material 6.
1 is open.

The filter cloth 4 is made of a stretchable material, and its peripheral edge is fixed along the upper end surface of the lower mold 2. The elastic sheet 5 covers the mold surface 30 so as to be in close contact with the entire mold surface 30 of the upper mold 3, leaving the injection port 71, and only the outer peripheral edge portion of the elastic sheet 5 and the peripheral edge portion of the injection port 71. However, it is airtightly integrated with the upper mold 3.

The elastic sheet 5 has a thick portion 51 which is in close contact with the lower end surface 31a of the convex portion 31 and a side surface 31b of the convex portion 31.
And a thin portion 52 that is in close contact with
It is 2 to 3 times thicker than 2. This molding device 1
a is as described above, and the hydraulic inorganic molded product can be molded as follows.

First, the lower mold 2 and the upper mold 3 are closed, and the injection port 7 is inserted into the mold cavity having a substantially concave cross section formed by this closing.
The hydraulic inorganic molding material 6 is injected from 1. By this injection, the filter cloth 4 provided on the lower mold 2 extends and comes into close contact with the mold surface 20 of the lower mold 2. Therefore, the hydraulic inorganic molding material 6 is injected into the shape along the inner shape of the mold cavity.

Next, the drain hole 21 provided in the lower mold 2
While sucking and dehydrating excess water of the molding material 6 in the mold cavity, the pressurizing medium buffer tank 32 and the pressurizing medium press-fitting hole 33 are provided.
A pressurizing medium is press-fitted between the mold surface 30 of the upper mold 3 and the elastic sheet 5 to bulge the elastic sheet 5 toward the molding material 6 side. A concave shaped object W is obtained.

Then, the upper and lower molds 3 and 2 are opened, the shaped product is taken out from the lower mold 2 and cured and cured to obtain a predetermined molded product. That is, according to this molding apparatus 1a, when the pressurizing medium is press-fitted into the elastic sheet 5, the thick-walled portion 51 that comes into close contact with the concave bottom surface portion of the shaped object W to which the relatively high pressure of the elastic sheet 5 is applied. Since the thin portion 52 that adheres to the concave rising portion of the shaped object W to which only a relatively low pressure is applied bulges toward the shaped object W side at the same bulging rate, W is compressed with a uniform pressure over the whole, and it becomes possible to obtain a denser and more accurate molded body.

2 and 3 show an embodiment of the molding apparatus according to claim 2. As shown in FIGS. 2 and 3, in the molding apparatus 1b, a large number of pressurizing medium press-fitting holes 33 ′ provided in the mold surface 30 ′ of the upper mold 3 ′ are adjacent to other pressurizing medium press-fitting holes 33. The molding apparatus 1a is the same as the molding apparatus 1a except that the elastic sheet 5'is connected to the mold sheet 30 'through a groove 37' provided along the mold surface 30 'and the elastic sheet 5'has a uniform thickness as a whole. .

That is, according to this molding apparatus 1b, a molded product is molded in the same manner as the molding apparatus 1a, but a large number of pressurizing medium press-fitting holes provided in the mold surface 30 'of the upper mold 3'. Since 33 'is connected to another adjacent pressurizing medium press-fitting hole 33' through a groove 37 'provided along the mold surface 30', the pressurizing medium is connected to the mold surface 30 'and the elastic sheet 5. '
When press-fitted between the pressurizing medium and the pressurizing medium, the pressurizing-medium pressing-in hole 33 'is immediately inserted from the pressurizing-medium pressing-in hole 33' through the groove 37 '.
And the pressurizing medium press-fitting hole 33 '.

Therefore, the entire elastic sheet 5'is instantly and uniformly bulged to the side of the shaped object W, the entire shaped object W can be uniformly compressed, and a more compact and accurate molded product can be obtained. Like

[0029]

Embodiments of the present invention will be described below in detail. (Example 1) A lower mold 2 of 800 mm x 400 mm x 300 mm, which is made of general structural rolled steel (SS41) and has a large number of water drain holes having a diameter of 3 mmφ formed at a pitch of 50 mm on a mold surface 20, and an upper part. A molding apparatus 1a shown in FIG. 1 including a mold 3, a stretchable filter cloth 4 made of acrylic fiber, and an elastic sheet 5 made of natural rubber having a thick portion 51 having a thickness of 30 mm and a thin portion 52 having a thickness of 10 mm. I prepared.

First, after the upper and lower molds 3 and 2 are closed, a molding material 6 having the following composition is press-fitted at a pressure of 5 kg / cm ² to fill the inside of the mold cavity and a water drain hole of the lower mold 2. Two
Excess water in the molding material 6 is sucked and dewatered at a pressure of 1 to −600 mmHg, and water as a pressurizing medium is further injected through the buffer tank 32 and the pressurizing medium press-fitting hole 33 at an injection pressure of 20 kg / cm ^2. It is press-fitted between the surface 30 and the elastic sheet 5, and the elastic sheet 5 compresses the molding material 6 in the mold cavity to form the shaped object W.
I got

The upper and lower molds 3 and 2 were opened, the shaped product W was taken out from the lower mold 2 and cured by curing to obtain a molded product. [Mixing of molding material 6] Ordinary Portland cement (manufactured by Ube Industries, Ltd.) 100 parts by weight Cellofiber (manufactured by Hyogo Pulp Industry) 2.5 parts by weight Water 500 parts by weight

(Comparative Example 1) The elastic mold sheet 20 has the same mold cavity shape as that of Example 1 and is made of rubber as shown in FIG.
A molded product was obtained in the same manner as in Example 1 except that the molding apparatus equipped with No. 3 was used.

The molded articles obtained in Example 1 and Comparative Example 1 were divided into a concave bottom portion (bottom portion) and a portion rising from both sides of the bottom portion (raising portion).
Cut out as a test body No. 5 into a plate shape of 20 cm × 15 cm, and perform a bending strength test based on the bending test method for building boards of JIS method A1408 using this plate-like test body and measure the specific gravity by the following method. As a result, the results are shown in Table 1 below.

[Specific gravity measurement method] (1) A material obtained by cutting the secondary curing completed product into a size of width 100 x length 100 mm was left still in water for 24 hours with the upper surface of the sample positioned 100 mm below the water surface. Then, the underwater weight (Wf) of the sample is measured. (2) Remove the sample from water, wipe off the moisture with a dry cloth and measure the saturated water weight (We), then dry for 24 hours with a dryer with an air agitator (temperature 105 ± 5 ° C) and then cool to room temperature in a desiccator. Let (3) After cooling to room temperature, the absolute dry weight (Wg) of the sample is measured. (4) Underwater weight (Wf) and saturated water weight (W) obtained above
e), by absolute dry weight (Wg) Specific gravity = Wg / (We-
It is calculated using the formula of Wf).

[0035]

[Table 1]

As shown in Table 1, the molded article of Example 1 was
It can be seen that the bending strength and the specific gravity are more stable than the molded product of Comparative Example 1. That is, according to the molding apparatus of the present invention, it is possible to obtain a more uniform product quality.

Example 2 Rolled steel for general structure (SS4)
1), a lower mold 2 having a size of 800 mm × 400 mm × 300 mm, in which a large number of water draining holes having a diameter of 3 mmφ are formed at a pitch of 50 mm on the mold surface 20, an upper mold 3 ′, and an acrylic fiber elastic filter. The cloth 4, the elastic sheet 5 ′, and a large number of pressurizing medium press-fitting holes 31 ′ provided on the die surface 30 ′ of the upper die 3 ′ are adjacent to other pressurizing medium press-fitting holes 31 ′ and the die surface 30 ′. A molding apparatus 1b shown in FIG. 2 having a groove 37 'having a depth of 2 mm and a width of 3 mm provided along the groove was prepared.

First, after closing the upper and lower molds 3 ', 2, the molding material 6 having the same composition as in Example 1 was pressed into the mold cavity at a pressure of 5 kg / cm ² and the lower mold 2 was Excess water in the molding material 6 is sucked and dehydrated from the water drain hole 21 at a pressure of −600 mmHg, and water as a pressurizing medium is further supplied through the buffer tank 32 ′ and the pressurizing medium pressurizing hole 33 ′.
A molding material 6 ′ in the mold cavity was compressed by the injection pressure of kg / cm ² between the mold surface 30 ′ and the elastic sheet 5 ′ to obtain a shaped article W ′.

The upper and lower molds 3 ', 2 were opened, and the shaped product W'was taken out from the lower mold 2 and cured by curing to obtain a molded product.

(Comparative Example 2) The same mold cavity shape as that of Example 2 is formed, and the mold surface 202 of the upper mold 201 is formed as shown in FIG.
A molded product was obtained in the same manner as in Example 2 except that the groove was not provided in the above.

The molded products obtained in Example 2 and Comparative Example 2 were also subjected to bending strength and specific gravity measurements based on the same tests as in Example 1 and Comparative Example 1, and the results are shown in Table 2 below. It was a result.

[0042]

[Table 2]

As shown in Table 2, the molded article of Example 2 was
It can be seen that the bending strength and the specific gravity are more stable than the molded product of Comparative Example 2. That is, according to the molding apparatus of the present invention, it is possible to obtain a more uniform product quality.

[0044]

EFFECTS OF THE INVENTION Since the hydraulic inorganic molded article molding apparatus according to the present invention is configured as described above, it is possible to obtain a dense and high-strength molded article by using the present molding apparatus. Of course, it is possible to mold a hydraulic inorganic molded product having uniform specific gravity and strength.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a molding apparatus for a hydraulic inorganic molded article according to claim 1 of the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of a molding apparatus for a hydraulic inorganic molded article according to claim 2 of the present invention.

FIG. 3 is a perspective view showing grooves on a mold surface of the molding apparatus of FIG.

FIG. 4 is a cross-sectional view showing a known molding device for a hydraulic inorganic molded product.

FIG. 5 is a cross-sectional view showing a molding apparatus of a hydraulic inorganic molded article proposed by the inventor.

[Explanation of symbols]

1a, 1b Molding device 2 Lower mold (first split mold) 21 Drainage hole 3, 3'Upper mold (second split mold) 33, 33 'Pressurized medium press-fitting hole 37' Groove 5, 5 'Elastic sheet 51 Thickness Meat portion (portion to which press-in pressure of pressurized medium is high) 52 Thin portion (other portion) 6 Hydraulic inorganic molding material

Claims (2)

[Claims] 1. A first split mold in which a large number of water drain holes are formed along a mold surface, and a second split mold in which the mold surface is covered with an airtight elastic sheet whose periphery is hermetically sealed. The hydraulic inorganic molding material is press-fitted into the mold cavity formed by closing and, and excess water in the hydraulic inorganic molding material is sucked and dehydrated through the water drain holes formed in the mold surface of the first split mold. Then, the elastic sheet is shaped into a desired shape, and the elastic sheet is bulged toward the first split mold side by press-fitting a pressurizing medium between the elastic sheet and the mold surface of the second split mold. In a molding device for a hydraulic inorganic molding material that is configured to compress a hydraulic inorganic molding material, the elastic sheet has a swelling ratio with other portions in a portion where the pressurizing pressure of the pressurizing medium is high. In order to make it uniform, a thick part thicker than the other parts is provided. An apparatus for molding a hydraulic inorganic molded article, which is characterized in that 2. A first split mold in which a large number of water drain holes are formed along a mold surface, and a second split mold in which the mold surface is covered with an airtight elastic sheet whose periphery is hermetically sealed. The hydraulic inorganic molding material is press-fitted into the mold cavity formed by closing and, and the excess water in the hydraulic inorganic molding material is suction-dehydrated from the water draining hole formed in the wall surface of the first split mold. Shape into a desired shape by pressing, and pressurizing a pressurizing medium between the elastic sheet and the mold surface of the second split mold causes the elastic sheet to swell toward the first split mold side and water through the elastic sheet. In a molding device for a hydraulic inorganic molding material, which is configured to compress a hard inorganic molding material, a mold surface of the second split mold is provided with a space between the elastic sheet that is opened and the mold surface of the second split mold. It has a large number of pressurizing medium press-fitting holes for pressurizing the pressurizing medium. Among them, the adjacent holes are connected to each other via a groove provided along the mold surface of the second split mold, and a molding device for a hydraulic inorganic molded product, wherein: