JPS61157334A - Apparatus for preparing fine powdery stock material in dry state by dispersing and mixing carbon staple fiber in monofilament state - Google Patents

Abstract

PURPOSE:To uniformly disperse and mixing a carbon stable fiber, by providing a carbon stable fiber aggregate supply apparatus above upper rotors while providing a pair of lower rotors, which has a large number of fine projections provided to the surface thereof at small intervals, below said upper rotors. CONSTITUTION:Small lumps of sufficiently separated carbon stable fibers between upper rotors 1, 2 are passed between elastic fine wires 9, 10 of lower rotors 7, 8. At this time, said small lump are disentangled by elastic fine wires 9 having a high peripheral speed while pressed by elastic fine wires 10 having a slow peripheral speed and the elastic fine wires 9, 10 are vibrated to perfectly separate the small lumps of the carbon staple fibers insufficient to separate into individual monofilaments. The carbon staple fibers passed between a pair of the lower rotors 7, 8 and dispersed in a monofilament state are fallen in a mixer 11 as they are and uniformly mixed with fine powdery stock materials such as cement mortar or a mixing agent without again being flocculated.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to an apparatus for producing a dry fine powder raw material in which short carbon fibers are uniformly split and mixed into single fibers.

(Prior art) Carbon fibers with a diameter of about 5μ to 20μ made from raw materials such as pitch and 100+a&J! Short fibers cut into various lengths up to It is also known to significantly increase mechanical strength without compromising heat resistance or chemical stability.

However, when short carbon fibers are uniformly added to the powder or fluid raw material before being shaped to make this product, some vibration r N t'A1. + When agitation or other force is applied, adjacent short fibers intersect and overlap each other, as if short fine hairs were swept together, forming a soft, cotton-like aggregate. Tend.

Although the adhesive bonds between the short edges of this aggregate are not very strong, they cannot be easily loosened with fingers. However, the above-mentioned properties of short carbon fibers are a major drawback when they are added to a powdered or fluid raw material before being shaped into a molded article and uniformly dispersed and mixed.

This is because, if short carbon fibers are mixed into the raw material for a molded product in the form of an aggregate containing many small aggregates as described above, these aggregates will be damaged by subsequent stirring of the raw material, cross-talk, and other unforeseen problems. Depending on the dispersion method used, the carbon short fibers are not separated into single fibers, and even the once separated short carbon fibers re-agglomerate into small spheres in the raw material for the molded product. This is because fibers in a uniformly dispersed state cannot be obtained.

Therefore, extremely complicated methods must be used to obtain raw materials for mortar, slate plates, cast concrete molded products, etc. in which the short carbon fibers described above are uniformly mixed. That is, an aggregate of h-pon short fibers is put into a suitable liquid material such as water to be kneaded with cement, or into a fluidized raw material containing cement, and the mixture is stirred little by little with a special mixer to form a uniform fluid state. It is necessary to undergo an operation to form a dispersed solid-liquid mixture.

Needless to say, the above method, which can be called a wet method, is inefficient and continuous.

Recently, this type of molding material has come to be distributed as a single package containing a mixture of various solid material additives, and if necessary, it can be kneaded with water or the like to form mortar.

This is a so-called composite material premix product.

However, due to the above-mentioned problems, it is not possible to create a one-pack product made of solid powder/granular composite material with added short carbon fibers, and even if it were made, the short carbon fibers would agglomerate over time, making it unusable. It becomes impossible to provide. This is extremely inconvenient and does not match the trends of the times.

As described above, although there are great expectations and demands for mortar containing short carbon fibers, slate boards, cement tiles, and concrete molded products due to their excellent properties, the actual implementation of these products is negligible. The current situation is that there is.

2. Therefore, it would be advantageous if it were possible to obtain a composite cement in which the individual short carbon fibers were relatively sufficiently separated from each other and dispersed together in a dry state from the beginning in a granular solid raw material containing the above-mentioned cement powder, etc. be. Similarly, it would be of great benefit if short carbon fibers could be defibrated into single fibers and mixed into various molten glasses, molten resins, and uncured resin raw materials in a dry state as described above.

In order to do this, it is necessary to mechanically separate the aggregated aggregated short carbon fibers into single fibers by a so-called dry method without using a liquid medium, or to prevent the agglomeration tendency and form the separated single fibers. It is necessary to add it to the raw material as is. However, such dry defibration of short carbon fibers has been attempted by large companies, but none have succeeded.

(Objective) The object of the present invention is to provide an apparatus for obtaining a dry fine powder raw material in which short carbon fibers are uniformly dispersed and mixed in the form of single fibers.

(Structure) In order to achieve the above object, the present invention has a pair of upper rotary bodies each having a large number of fine protrusions erected at small intervals on the surface thereof, which are opposed to each other so that the tips of both fine protrusions move relative to each other with a slight gap between them. A short carbon fiber aggregate supplying device is arranged above the carbon short fiber aggregate supply device, and a pair of lower rotating bodies each having a large number of fine protrusions erected at small intervals on the surface thereof are disposed below. The thin protrusions intersect between the fine protrusions of the upper rotating body, and the fine protrusions either slightly intersect with each other, do not intersect with each other, or have a slight gap, and at least one of the fine protrusions of the pair of lower rotary bodies is connected with an elastic thin wire. The present invention is characterized in that it is equipped with a means for mixing the short carbon fibers passed between the lower rotating bodies and separated with a fine powder raw material. A detailed explanation will be given below based on examples. 1 is a thick-walled steel cylindrical upper rotating body with an outer diameter of 40 cm and a width of 80 (1),
2 is a similar upper rotating body with an outer diameter of 20 mm.

On the surface of the rain upper rotating body 1.2 with a width of 80 crn, there are thin protrusions 3, 4 with a pointed triangular tip and a length of about 6 W without elasticity.
are fixed at a pitch of 3 m, and the tips of the thin protrusions 3.4 are opposed to each other with an interval of about 1 electric current. The upper rotating body 1 is arranged to rotate counterclockwise at a speed of 400 revolutions per minute, and the upper rotating body 2 is arranged to rotate clockwise at a speed of 20 revolutions per minute. A hopper 5 is disposed above the opposing part of the pair of upper rotors 1 and 2, and collects carbon short fibers, which are carbon short fibers with a diameter of about 15 μm and a length of about 3 fibers, aggregated into small lumps of irregular size. A cluster 6 is included. A pair of lower rotating bodies 7 and 8 are disposed below the upper rotating bodies 1 and 2, and a large number of thin elastic wires 9 and 10 each having a length of 20 mm are erected at small intervals on the surface.
, 10 intersect with the thin protrusions 3 and 4 of the upper rotary bodies 1 and 2, respectively, and the tips of the elastic wires ``@9.10'' slightly intersect with each other.The lower rotary body 7 has an outer diameter of 130 mm. Width 80cIn
The lower rotating body 8 rotates counterclockwise at 100 revolutions per minute.
has an outer diameter of 13 mm and a width of 80 mm and rotates clockwise at 30 revolutions per minute. 11 is a mixer into which fine powder raw materials such as cement mortar and admixtures are charged.

Next, the effect will be explained. The short carbon fiber aggregates 6 supplied from the hopper 5 between the pair of upper rotating bodies 1 and 2 have a slow circumferential speed and are held by the thin protrusions 4 of the upper rotating body 2, while the short carbon fiber aggregates 6 are held by the narrow protrusions 4 of the upper rotating body 1, which has a high circumferential speed. It is loosened by the thin protrusions 4, and most of it is divided into single fibers and falls downward. The remaining short carbon fibers adhering between the thin protrusions 3 and 4 of the pair of upper rotating bodies 1 and 2 are scraped off by the lower rotating bodies 7 and 80 and the elastic thin wires 9 and 10. When the small pieces of short carbon fibers that have been insufficiently separated between the upper rotating bodies 1 and 2 pass between the lower rotating bodies 7 and 80 and the thin elastic wire 9° and 10, they are held down by the thin elastic wire 10 with a slow circumferential speed. Elastic line with high circumferential speed @9,
□23. Wow. . Engineering. @9,10'' vibrates, and due to this vibration, the small lumps of carbon short fibers that have been insufficiently separated are completely separated into single fibers one by one. The short carbon fibers passed through the rotating bodies 7 and 8 and split into single fibers fall into the mixer 11 as they are, and are uniformly mixed into fine powder raw materials such as cement mortar and admixtures. No reaggregation.

Note that at least one of the pair of lower rotating bodies may be an elastic thin wire, and the tips of the elastic thin wires or thin protrusions of the pair of lower rotating bodies may not intersect or may be slightly spaced apart. Alternatively, instead of a mixer, a fine powder raw material may be injected from the lower side of a pair of lower rotating bodies onto the separated and falling short carbon fibers to mix them.

(Effects) According to the present invention, a pair of upper rotating bodies each having a large number of fine protrusions erected at small intervals on its surface are arranged facing each other so that the tips of both fine protrusions move relative to each other with a slight gap, and A short carbon fiber aggregate supply device is installed at the top, and a pair of lower rotating bodies each having a large number of fine protrusions erected at small intervals on the surface thereof are placed below, and each fine protrusion is connected to the fine protrusions of the upper rotating body. The thin protrusions intersect with each other, and the thin protrusions slightly intersect with each other, do not intersect with each other, or have a slight gap. It is equipped with a means to mix the short carbon fibers that have passed through the filter and been split into fine powder raw materials, so that the short carbon fiber aggregates, which have a strong cohesive force and are agglomerated into small clumps, can be separated one by one without being damaged. A dry fine powder raw material can be obtained by dividing into fibers and dispersing and mixing them as they are.

[Brief explanation of drawings]

FIG. 1 is a front view of an embodiment of the present invention. 1.2... Upper rotating body, 3, 4... Thin protrusions, 5...
・Hopper, 6... Carbon short fiber aggregate, 7, 8・
...Lower rotating body, 9, 10... Elastic thin wire, 11...
mixer. Patent applicant: Irie Wall Materials Co., Ltd. Agent: Kai Ito Sake 5゛--1

Claims (1)

[Claims] A pair of upper rotating bodies each having a large number of fine protrusions erected at small intervals on its surface are arranged facing each other so that the tips of both fine protrusions move relative to each other with a slight gap, and short carbon fiber aggregates are supplied above them. The device is installed, and a pair of lower rotating bodies each having a large number of fine protrusions erected at small intervals on the surface are disposed below, and each fine protrusion intersects between the fine protrusions of the upper rotary body. The protrusions may slightly intersect with each other, do not intersect with each other, or have a slight gap, and at least one of the thin protrusions of a pair of lower rotating bodies is an elastic thin wire, which is passed between the lower rotating bodies and separated. An apparatus for producing fine powder raw material in a dry state in which short carbon fibers are dispersed and mixed in the form of single fibers, and is equipped with means for mixing short carbon fibers with fine powder raw materials.