JP2965384B2 - Method for producing fiber molded article and suction mold - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a fiber molded product having a partially different thickness and a suction mold used for the method.

[0002]

2. Description of the Related Art Various fiber molded products are used in automobiles, chemical devices, water heaters, heaters and the like. These fiber molded products are used as cushioning materials, sealing materials, heat insulating materials, and the like. The fibers may be synthetic resin fibers such as polyamide and polyester fibers,
Examples include natural fibers such as cellulose pulp and hemp, and inorganic fibers such as ceramic fiber and glass fiber. Then, in manufacturing the above-mentioned fiber molded product, as shown in FIG. 9, the fiber 80 is suspended in a liquid (water) to form a slurry 901 and this is mixed with the porous mold surface 9.
The slurry is fed into a suction mold 9 having a slurry pump 2 using a slurry pump 902. In the suction mold 9, the porous mold surface 9
2 from the decompression chamber 93 provided behind the slurry 901.
Aspirate the liquid inside.

[0003] As a result, the fibers 80 are sucked and deposited on the porous mold surface 92, and the outer shape is changed to the porous mold surface 9.
Thus, a fiber molded product (see FIG. 8 described later) along the inner wall surface is obtained. At the time of the above suction, the suction pump 9
7 is operated to reduce the pressure in the decompression chamber 93 through the pipe 96 and the suction box 94 of the suction mold 9. Then, the liquid in the slurry is discharged by the suction pump 97.

[0004] The decompression chamber 93 is provided with a porous mold surface 92.
And the outer cylinder 91. Further, as the porous mold surface 92, a porous plate having a large number of pores (3 to 15 mm in diameter) or a porous material capable of separating the fiber and the liquid, such as a fine metal mesh, is used. Further, in the above manufacturing method, a fiber molded article having a bottomed cylindrical shape is obtained. By the way, many fiber molded products have substantially the same thickness at the side wall and the bottom. For example, the bottom is required to have a larger thickness than the side wall. That is, a fiber molded product having a partially different thickness is required (see FIG. 8).

Conventionally, when manufacturing fiber molded products having different thicknesses as described above, a three-stage method is used as shown in FIG. That is, first, as shown in FIG. 9, the slurry 901 is put into the suction mold 9, and as shown in FIG. 8 (A), the whole thickness is substantially the same and the thickness is about half of the final thickness. A fiber molded product 81 is made. Therefore, the supply of the slurry was temporarily stopped, and FIG.
As shown in FIG.
The thickness adjusting plate 85 is placed on the bottom where the thickness is to be increased. Thereafter, the slurry is again charged into the suction mold with the intermediate fiber molded article 81 placed thereon, and suction molding is performed. As a result, as shown in FIG. 8C, a final fiber molded product 83 having the bottom portion 832 having a large thickness and the side wall 831 having the final thickness is obtained.

[0006]

However, the above-mentioned conventional method requires the thickness adjusting plate 85 and the steps of producing the intermediate fiber molded article 81, placing the thickness adjusting plate 85, and subsequently performing the final suction molding. It is. Therefore, productivity is low. Further, since the thickness adjusting plate 85 placed in the fiber molded product is different from the fiber constituting the main body, the portion may be deformed during use of the fiber molded product. SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and has as its object to provide a method of manufacturing a fiber molded product which is easy to mold and has excellent productivity, and has a partially different thickness, and a suction mold for the same.

[0007]

According to the present invention, a slurry is prepared by suspending fibers in a liquid, the slurry is introduced into a suction mold having a porous mold surface, and the liquid in the slurry is dispersed in the porous mold surface. Suction into the decompression chamber provided behind, and forming a fiber molded product on the porous mold surface,
Using a suction mold having a plurality of divided porous mold surfaces and a decompression chamber corresponding to each of the porous mold surfaces, the slurry is suctioned in a state where the suction pressure of the decompression chamber is varied, and And a method for producing a fiber molded article characterized by obtaining a fiber molded article having a different thickness. The most remarkable point in the present invention is that the above-mentioned slurry is suctioned by using a suction mold having a plurality of partitioned porous mold surfaces and a decompression chamber and changing the suction pressure of the decompression chamber.

Each of the porous mold surfaces has a corresponding decompression chamber behind it. The number of the porous mold surfaces is arbitrary, but at least the number of different thicknesses is necessary. For example, when the bottom and the side wall of the fiber molded product have different thicknesses, a porous mold surface divided into the bottom and the side wall and a decompression chamber are required (see Examples). In this case, for example, the porous mold surface for forming the side wall and the decompression chamber are all set to the same suction pressure, and the porous mold surface for the bottom portion and the decompression chamber are set to another suction pressure (see FIG. 1). When it is desired to further increase the thickness of the side wall to two types, the porous mold surface for the side wall is divided into two sets and the bottom part is also divided, thereby forming three sets of the porous mold surface and a decompression chamber. In addition, as shown in the embodiment, in order to facilitate removal of the fiber molded product, when the suction mold is a split mold, the porous mold surface and the decompression chamber are, for example, 5 mm.
It may be divided into sections (see FIGS. 4 and 5). Also,
As a method of adjusting the suction pressure, there is a means for changing the opening area of the suction port between the decompression chamber and the suction box.

[0009] As the suction mold for carrying out the above-mentioned manufacturing method, a porous mold surface divided into a plurality of sections, a decompression chamber provided behind each porous mold surface, and a suction pump for connecting to a suction pump are provided. A suction mold having a box, a separator disposed between the decompression chamber and the suction box, and a suction port provided in the separator to communicate the two, wherein the suction of the decompression chamber having a different suction pressure is performed. The mouth has a fiber molded product characterized by different opening areas, and a suction mold for production. The suction port is provided in a separator that partitions the decompression chamber and the suction box. When a plurality of suction ports are provided in one partition plate (FIG. 3), the opening area is the total opening area.

[0010]

In the manufacturing method of the present invention, the suction of the slurry is carried out by using a suction mold having a plurality of partitioned porous mold surfaces and a decompression chamber, and changing the suction pressure of the decompression chamber. Therefore, a large amount of fibers accumulate on the surface of the porous mold surface where the suction pressure is large, and a small amount of fibers accumulate on the surface of the porous mold surface where the suction pressure is small. Therefore, a fiber molded product having a partially different thickness can be obtained. Further, in the present invention, since the thickness adjusting plate is not used unlike the conventional method, the steps of suction molding of the intermediate fiber molded product, arrangement of the thickness adjusting plate, and final suction molding are not required. Therefore, it is easy to manufacture and excellent in productivity.

Further, since the thickness adjusting plate is not inserted in the fiber molded product, the whole is uniform and there is no possibility of distortion. In the above suction mold, the suction pressure can be adjusted by making the opening area of the suction port different, and the apparatus is simple. As described above, according to the present invention, it is possible to provide a method for producing a fiber molded product which is easy to mold and has excellent productivity and partially differs in thickness. Further, it is possible to provide a suction mold exhibiting such an effect.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for producing a fiber molded article and a suction mold according to an embodiment of the present invention will be described with reference to FIGS. First, the fiber molded product 7 to be obtained in the present example is a box-like body having a bottom portion 73 and a square side wall 72 as shown in FIGS. And the bottom 7
3 has a thickness about three times that of the side wall 72. Also,
One opening hole 71 is provided in the side wall. The fiber molded product 7 is a heat insulating case arranged to cover the outer periphery of the gas water heater. The opening 71 is an insertion portion of a burner to be inserted into the gas water heater.

Next, a suction mold 1 for suction-molding the fiber molded article 7 will be described with reference to FIGS. As shown in FIGS. 1 to 3, the suction mold 1 includes a plurality of porous mold surfaces 12, 13, pressure reducing chambers 15, 130 provided behind the porous mold surfaces 12, 13, and a suction mold. It comprises a suction box 16 for connection to a pump 97 and a plate-like separator 17 provided between the decompression chamber 16 and each of the decompression chambers 15 and 130. Further, the separator 17 has suction ports 171 and 173 for communicating the decompression chambers 15 and 130 with the suction box 16.

The total opening area of the eight suction ports 171 communicating with the decompression chamber 15 and the opening area of the suction ports 173 are larger in the latter. In this example, the suction port 32 is about 1.
It has three times the opening area. Further, the porous mold surface 12,
The decompression chamber 15 is used for forming the side wall 72 of the fiber molded product 7.
The porous mold surface 13 and the decompression chamber 130 are portions used for forming the bottom 73 of the fiber molded product 7. As shown in FIGS. 2 and 3, the separator 17 has a suction port 171 communicating with each decompression chamber 15 and a suction port 173 communicating with the decompression chamber 130 for bottom molding. The decompression chamber 130 is formed by the porous mold surface 13, the separator 17, and a partition 131 provided in an elliptic cylindrical shape between the two. As will be described later, the suction mold 1 is a split mold that opens in four directions (FIGS. 4 and 5).

The decompression chamber 15 for forming the side wall is formed between the porous mold surface 12 and the outer cylinder 11.
Reference numeral 5 denotes 4 of each of the decompression chambers 151 to 154, as shown in FIG.
It is divided into pieces. That is, each of the decompression chambers 151 to 154
Is formed between the porous mold surfaces 121 to 124 and the outer cylinder 11. A blind plate 18 is formed below the porous mold surface 122 to form an opening hole 71 (FIG. 6) of the fiber molded product 7, that is, to prevent fibers from being adsorbed.
Is provided. In FIG. 1, reference numeral 150 denotes a common decompression chamber common to the decompression chambers 151 to 154. The outer cylinder 11 is composed of outer cylinder plates 111 to 114. That is, the porous mold surfaces 121 to 124, the decompression chambers 151 to 154, and the outer cylinder plates 111 to 114 each constitute one set, and are configured to be openable in four directions as shown in FIGS. . These sets are connected by hinges 136 near the bottom forming porous mold surface 13 (FIG. 1).

Next, in the suction molding, the slurry is supplied into the suction molding die 1 and the suction pump 97 is operated as in the conventional case. And each decompression chamber 151-
The pressures of 154 and 130 are reduced, and the liquid in the slurry is separated by suction (in the direction of the arrow in FIG. 1). As a result, the fibers are suction-deposited on the surfaces of the porous mold surfaces 121 to 124 and 13, and the fiber molded product 7 is formed. At this time, since the blind plate 18 has no suction force, an opening hole 71 of the fiber molded product 7 is formed in this portion. What is important here is that the separator 1
7, the total opening area of the suction port 171 provided between the decompression chambers 151 to 154 and the suction box 16 is the same as the suction port 13 between the decompression chamber 130 for forming the bottom and the suction box 16.
2 is smaller than the opening area.

Therefore, the suction pressure in the decompression chamber 130 is
It becomes higher than the suction pressure of the decompression chambers 151 to 154. Therefore, the porous mold surfaces 121 to 12
4 more fibers are suction deposited. Therefore, as shown in FIG. 7, it is possible to obtain the fiber molded article 7 in which the thickness of the bottom portion 73 is larger than that of the side wall 72. In this example, a water slurry containing ceramic fibers having a diameter of 2.5 μm and a length of 25 mm was used as the fibers. At the time of suction molding, the suction pressure of the decompression chambers 151 to 154 is about 400 to 500 mmH.
g, suction pressure of the decompression chamber 130 is about 550-650 mmH
g. The fiber molded product 7 had a side wall thickness of about 10 mm and a bottom thickness of about 17 mm. As described above, according to the present embodiment, it is possible to provide a method of manufacturing a fiber molded product which is easy to mold and has excellent productivity, and has a partially different thickness, and a suction mold.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a suction mold in an embodiment.

FIG. 2 is a lower sectional view of the suction mold of the embodiment.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a sectional view taken along line BB of FIG. 2;

FIG. 5 is a plan view showing a state in which the suction mold of the embodiment is opened.

FIG. 6 is a perspective view of a fiber molded product obtained in an example.

FIG. 7 is a sectional perspective view of the fiber molded product of FIG. 6;

FIG. 8 is a manufacturing process diagram of a conventional fiber molded product.

FIG. 9 is an explanatory view of a method of manufacturing a fiber molded product in a conventional example.

[Explanation of symbols]

 1. . . Suction mold, 11, 111-114. . . Outer cylinder, 12, 121-124. . . 12. porous mold surface for forming side walls; . . 130. porous mold surface for bottom molding . . Decompression chamber for bottom molding, 15, 151-154. . . 15. decompression chamber for forming side walls; . . Suction box, 17. . . Separator, 171,173. . . Suction port, 18. . . Blind plate,

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-57-71500 (JP, A) JP-B-54-19256 (JP, B2) (58) Fields investigated (Int. Cl. ⁶ , DB name) D21J 7/00

Claims (2)

(57) [Claims] A slurry is prepared by suspending fibers in a liquid, and the slurry is introduced into a suction mold having a porous mold surface, and the liquid in the slurry is provided behind the porous mold surface. A method of forming a fiber molded product on a porous mold surface by suction into a vacuum chamber, using a suction mold having a plurality of partitioned porous mold surfaces and a vacuum chamber corresponding to each porous mold surface. A method of producing a fiber molded product, wherein the slurry is suctioned in a state where the suction pressure of the decompression chamber is made different to obtain a fiber molded product having a partially different thickness. 2. A plurality of porous mold surfaces, a decompression chamber provided behind each of the porous mold surfaces, a suction box for connecting to a suction pump, and a space between the decompression chamber and the suction box. What is claimed is: 1. A suction mold having a separator disposed therein and a suction port provided in the separator to communicate the two, wherein suction ports of decompression chambers having different suction pressures have different opening areas. Mold for producing fiber moldings.