JPH06807A - Molding apparatus - Google Patents

Abstract

PURPOSE:To provide a molding apparatus capable of obtaining a molding not causing disadvantages such as hanging down or trunk breakage. CONSTITUTION:A screen 11 comprising an abrasion proof wire netting is provided at an intermediate part between the auger screw 2 of an auger machine and a mouthpiece 4 attached at the downstream side thereof, and a fine-divided plate 14 formed by making a large number of holes 13 on a base plate 12 for reinforcing the screen 11 is disposed at the downstream side of the screen 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a molding apparatus in which a die is directly attached to a clay kneader to knead and extrude an extruding raw material such as ceramics by an auger screw and perform molding by the die.

[0002]

2. Description of the Related Art Conventionally, a die is directly attached to the downstream side of the tip of an auger screw of a clay kneader, and kneading / extruding a raw material such as ceramics and a binder with an auger screw and forming with a die. The device is known. FIG. 3 is a diagram for explaining a main part of the configuration of an example of a conventional molding apparatus. In the example shown in FIG. 3, 21 is a drum section of a clay kneading machine, and 22 is this drum section 2
Auger screw for kneading and extruding provided in 2.
Reference numeral 23 is a mouthpiece attachment portion provided on the downstream side of the tip portion of the auger screw 22, and 24 is a die for attachment attached to the tip end of the mouthpiece attachment portion 23.

Usually, a molded body made of ceramics or the like, which is molded by the above-mentioned molding apparatus, is subjected to calcination for removing the binder, if necessary, and then fired to manufacture a product. At that time, a long product that is difficult to form unless it is extruded, for example, a molded product for obtaining a long tubular body, etc., is bent straight due to gravity when it is laid sideways and baked on a jig. As it cannot be obtained, FIG.
As shown in FIG.
The so-called hanging firing is performed by firing in the state of being hung by No. 6.

[0004]

However, in the molded body molded by the conventional molding apparatus as described above, each part of the molded body as described in, for example, Japanese Patent Application Laid-Open No. 3-270904 filed by the applicant of the present invention. In this case, when the long shaped body is suspended and fired, the so-called hanging-down, in which the shaped body 25 is separated from the receiving jig 26 during the hanging and firing, frequently occurs, and the body portion of the shaped body 25 is cut. There was a problem that so-called body breakage occurred. Further, in hanging baking, a large number of molded bodies 25 are hung on the receiving jig 26 in order to simultaneously fire a plurality of molded bodies, but as described above, one molded body 2 is used.
When a drop-off or a break in the body occurs in 5, the molded body 25 hits another molded body 25, and a drop-in or a break in the body 25 occurs.
Not only that, there was also a problem that the surrounding molded body 25 also became a defective product.

An object of the present invention is to solve the above-mentioned problems and to provide a molding apparatus capable of obtaining a molded product which does not cause inconveniences such as hanging and breaking of the cylinder during firing.

[0006]

The molding apparatus of the present invention is provided with a screen made of a wear-resistant metal wire mesh between the auger screw of the clay kneader and the die provided downstream of the auger screw. It is characterized in that a subdivision plate constituted by forming a large number of holes in a substrate for reinforcing the screen is provided on the downstream side of the screen.

[0007]

In the above structure, the binder is sheared because the mixture of the raw material such as ceramics and the binder passes through the screen made of the wear-resistant metal wire mesh.
While passing through the screen and being re-bonded, it is possible to eliminate the occurrence of hard soil and the occurrence of lamination that cause breakage, and as a result, it is possible to obtain a molded product that does not drop off during firing or break into the body. Here, the hard soil means that the kneaded material attached to the vacuum chamber wall of the vacuum kneader dries and mixes into the kneaded material again, so that the mouth cannot be completely opened due to the difference in shrinkage rate during the drying and firing of the material. It means the cause. Further, since the subdivision plate provided integrally with the screen cannot withstand the pressure when the mixture of the raw material such as ceramics and the binder is passed only by the abrasion-resistant metal wire mesh, the reinforcing plate of the abrasion-resistant metal wire mesh is used. Plays a role as.

The mesh opening of the wear-resistant metal wire mesh is related to the maximum particle size of the raw material passing through. If it is less than 4 times the maximum particle size, a bridge may be formed in the raw material to form hard soil. In addition, since the shearing action of the binder may disappear when the thickness of the molded body exceeds the minimum thickness, it is preferable that the thickness is 4 times or more and the minimum thickness of the molded body or less. Further, the subdivision plate needs to fulfill the role of reinforcement, needs to have a certain thickness, and the minimum distance between the outer periphery of the substrate and the holes or the distance between the holes, in the case of a tubular body, If its thickness, in the case of a honeycomb structure, is smaller than the cell thickness,
It is preferable because there is no obstacle in the passage of raw materials.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram for explaining the main part of the constitution of an example of the molding apparatus of the present invention. In the embodiment shown in FIG. 1, 1 is a drum part of a kneading machine, 2 is an auger screw for kneading / extrusion provided in the drum part, and 3 is a mouthpiece provided on the downstream side of the tip part of the auger screw 2. The mounting portions 4 are caps for molding which are mounted on the base mounting portion 3, and these configurations are the same as those of the conventional example. In the molding apparatus of the present invention shown in FIG. 1, what is important is the middle of the tip portion of the auger screw 2 and the mouthpiece 4, here the mouthpiece mounting portion 3
In addition, a screen 11 made of stainless steel wire mesh is provided, and a substrate 1 for reinforcing the screen 11 is provided.
The point is that a subdivision plate 14 formed by forming a large number of holes 13 in 2 is provided integrally with the screen 11 on the downstream side of the screen 11.

The screen 11 can be composed of a commercially available stainless steel wire mesh, but the material of the screen 11 is not limited to stainless steel, and molybdenum, tungsten, etc., which are excellent in abrasion resistance, can also be used. The mesh used is preferably one having a mesh size of 4 times or more the maximum particle size of the raw material and not more than the minimum wall thickness of the molded body. For example, when the maximum particle size of the raw material is about 150 μm and the minimum wall thickness of the molded product is 1 mm, a wire mesh with a mesh size of 600 to 1000 μm is selected and used. Further, as the subdivision plate 14,
As shown in FIG. 2 which is a half-divided plan view of the example, a substrate 12 made of stainless steel and having a thickness of 9 mm is radially formed with holes 13 having a diameter of 4 mm. The thickness of the subdivision plate 14 may be the same at all positions, but if the subdivision plate 14 is made thinner toward the center, the resistance of the raw material passing through is reduced to the center. It is preferable because the amount can be made small and the raw material can be extruded uniformly.

An actual example will be described below. First,
Fused alumina WA # 280 (average particle size: 48 μm, maximum particle size:
112 μm) and 85 parts by weight of fine alumina (average particle size:
2 μm) to 15 parts by weight, 5 parts by weight of methyl cellulose as an organic binder for forming and 15 parts by weight of water were added, and the mixture was kneaded with a kneader to obtain a kneaded material for extrusion molding.

Next, as a conventional example, from the prepared kneading material for extrusion, a 100 type vacuum kneading machine (a drum diameter of the tip of the auger screw is 100 mm), an outer diameter of 32 mm, and a pin diameter of 4.5 mm × 19 pins are used. 1550 after drying the material extruded to a length of 1200 mm using the die
The binder was removed by calcination at ℃. After calcination, a hole for hanging and firing with a diameter of 6 mm was drilled at a position 30 mm from the end with a drilling machine, and then fired through hanging with a solid bar of molybdenum with a diameter of 5 mm in a reducing atmosphere of 1800 ° C., from the hanging hole. In addition to frequent disconnection and hanging, there were also body breaks due to hard soil.

On the other hand, as an example of the present invention, from the prepared kneading material for extrusion, a thickness of 15 mm and a diameter of 4 m are attached to the die attachment portion between the auger screw and the die of the 100 type kneader.
A subdivision plate with 216 m holes was attached, and a stainless steel wire mesh with an opening of 710 μm was placed as a screen on the auger screw side of this subdivision plate to form a material of the same shape as the conventional example, and after drying at 1550 ° C. After calcination, when reduction hanging baking was performed at 1800 ° C. in the same manner as in the conventional example, hanging down and breaking of the body did not occur at all.

Further, in order to find a preferable range of the examples of the present invention, first, in the above-mentioned examples of the present invention, the thickness of the subdivision plate was set to 9 mm, and the other conditions were the same as those of the above-mentioned examples of the present invention. , A bending occurred on the subdivision board. Therefore, it is understood that the thickness of the subdivision plate is preferably about 15 mm. In addition, when the mesh of the stainless steel wire mesh as the screen was made small, there was no particular problem at 590 μm and 500 μm, but when it was made fine at 420 μm, the fluidity of the kneaded material was significantly deteriorated, and the kneaded material on the screen was deteriorated. The passage was blocked, and the stainless wire mesh was deformed and abnormally worn. Therefore, it is understood that the minimum value of the mesh of the stainless steel wire mesh is preferably about 4 times the maximum particle size of the raw material to be passed.

Further, although the minimum thickness of the molding material in the above-mentioned embodiment is 1.2 mm, when the mesh of the stainless steel wire mesh as the screen is enlarged, 84
There was no particular problem at 0 μm and 1000 μm, but 119
At 0 μm and 1410 μm, body breakage due to hard soil occurred. Therefore, it is understood that the maximum value of the mesh size of the stainless steel wire mesh is preferably set to be equal to or less than the wall thickness of the material to be molded.

The present invention is not limited to the above-described embodiment, but various modifications and changes can be made. For example, in the above-described embodiment, an example in which the screen and the subdivision plate are provided in the base attachment portion between the auger screw and the base is shown, but the screen and the subdivision plate are other than this as long as they are between the auger screw and the base. It goes without saying that the same effect can be obtained even if it is provided in the place.

[0017]

As is apparent from the above description, according to the present invention, the binder is sheared because the mixture of the raw material such as ceramics and the binder passes through the screen and the dividing plate made of the abrasion-resistant metal wire mesh. It is possible to remove the occurrence of hard soil and the occurrence of lamination that cause cutting, as well as being re-bonded after passing through the screen.
As a result, it is possible to obtain a molded body that does not drop off or break during firing.

[Brief description of drawings]

FIG. 1 is a diagram for explaining a main part of a configuration of an example of a molding apparatus of the present invention.

FIG. 2 is a diagram for explaining the structure of a subdivision plate used in the molding apparatus of the present invention.

FIG. 3 is a diagram for explaining a main part of a configuration of an example of a conventional molding apparatus.

FIG. 4 is a diagram for explaining an example of hanging baking of a molded body.

[Explanation of symbols]

 1 Drum Part 2 Auger Screw 3 Base Attachment Part 4 Base 11 Screen 12 Board 13 Hole 14 Subdivision Plate

Claims (2)

[Claims] 1. A screen made of a wear-resistant metal wire mesh is provided between the auger screw of a clay kneader and a die provided downstream thereof, and a large number of holes are formed in a substrate for reinforcing the screen. A molding device, wherein a subdivision plate configured by opening the above is provided on the downstream side of the screen. 2. The molding apparatus according to claim 1, wherein the mesh size of the wire mesh forming the screen is at least 4 times the maximum particle size of the extruded raw material and not more than the minimum wall thickness of the molded body to be extruded.