JPH0365250A - Centrifugal fluid crushing apparatus - 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 [Industrial Field of Application] The present invention relates to a crushing device. More specifically, it relates to a wet-type centrifugal fluid milling device that is equipped with an outer ring and a rotating plate, and that grinds raw materials by centrifugally flowing a grinding medium such as steel balls or ceramic poles housed inside the device. be.

[Prior Art] There are various types of crushing devices such as tube mills and vertical mills, but by arranging a rotating plate facing upward and rotating this rotating plate, the steel balls or ceramics housed inside can be crushed. Grinding media such as poles (hereinafter referred to as poles)
A vertical ball mill, commonly called a vertical ball mill, is known in which the raw material is pulverized and milled by circulating the ball.

This type of vertical ball mill, which has been used for a long time, has problems such as weak grinding and grinding effects, or energy input into the device is easily consumed for purposes other than grinding and grinding, resulting in low energy efficiency. there were.

Therefore, the applicant filed a patent application for a centrifugal fluid crusher having a rotating plate and a fixed ring as shown below (Japanese patent application filed in 1980-
265379.60-266867-266872.6
1-99745 etc.).

This rotary plate has a rotation axis oriented in the vertical direction, has a plate surface whose diameter expands downward at least in the center, and is rotatable in a shape in which the longitudinal section of the plate surface is curved in a concave shape. It is plate-shaped.

The fixed ring has an inner wall surface whose diameter decreases upward at least in the upper part, and the longitudinal cross section of the inner wall surface is curved in a concave shape, and is disposed coaxially around the rotating blood and stationary. are doing.

In the centrifugal flow device, the plate surface of the rotating plate and the inner wall surface of the fixed ring are formed into continuous smooth surfaces except for a small gap between the rotating plate and the fixed ring.

[Problems to be Solved by the Invention] However, when the object to be crushed is ceramics such as silicon nitride or silicon carbide, magnetic materials, electronic materials, or face 4. When finely pulverizing fine powder that is a raw material for paint, for example, in order to obtain submicron fine powder of about 0.51 L from 100 g, a dry centrifugal fluidized pulverizer needs to use a dry centrifugal fluid pulverizer to cause the fine powder to coagulate. This requires extra processing such as crushing, making it extremely difficult to stably obtain submicron particles.

In addition, the particle size distribution of the product could only be obtained with a large spread, and it was difficult to obtain a narrow particle size distribution centered on submicron particles.

[Means for Solving the Problems] In order to solve the above problems and obtain a large number of submicron particles of these crushed materials through effective crushing, the apparatus of the present invention uses a wet crushing method, and the rotation axis is vertical. a rotatable circular rotary plate having a shape in which the vertical cross section of the plate face is curved in a concave shape, and the vertical cross section of the plate face is curved in a concave shape; A stationary ring whose upper part has an inner wall surface whose diameter decreases upward, and whose vertical cross section is curved in a substantially concave shape, and which is coaxially disposed around the rotary plate and is stationary. Equipped with.

A centrifugal fluid pulverizer, wherein the plate surface of the rotating plate and the inner wall surface of the fixed ring are formed into continuous smooth surfaces except for a small gap between the rotating plate and the fixed ring, A through hole is provided near the bottom of the rotating plate, circulation vanes for transporting a solid-liquid two-phase fluid containing the powder of the material to be crushed are provided on the lower surface of the outer periphery of the rotating plate, and the solid-liquid two-phase fluid containing the powder to be crushed is provided on the lower side of the rotating plate. The structure was equipped with a two-phase fluid container and a discharge port.

[Function] In the centrifugal fluid pulverizer of the present invention, fluid such as water is added to the material to be pulverized and the rotary plate is rotated around the vertical axis.
The fluid containing the fine powder produced as the grinding progresses moves into the container through the through hole provided near the bottom of the rotating plate, and is further moved into the container by the stirring action of circulation blades installed on the lower surface of the outer periphery of the rotating plate. The flow moves to the outer circumference of the rotating plate and rises through the small gap between the rotating plate and the fixed ring, forming a circulating flow.

In this way, the material to be crushed in the device becomes finer over time, and a product having the required powder particle size is obtained after a certain period of time.

Thereafter, the rotation of the rotary plate is stopped, and the fluid containing the fine powder is taken out from the outlet of the container, completing one batch operation.

Embodiments] Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 1 is an overall longitudinal sectional view of an apparatus according to an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of a main part showing another embodiment of the invention.

In FIG. 1, numeral 1 is a fixed ring, 2 is a rotating plate, 3 is a rotating shaft, 4 is a bearing box, 5 is a shaft coupling, 6 is a variable speed electric motor, and 7 is a rotary plate.
is a casing, 8 is an input chute for the material to be crushed, 9 is a pedestal, 10 is a container, 11 is a discharge port, 12 is a circulation blade, 23 is a crushing chamber, and 0 rotating plate 2 is a bearing box fixed to the casing 7. The casing 7 is supported and suspended by a bearing in the casing 7, and is rotationally driven by a variable speed electric motor 6 fixed to the top of the casing 7.

On the other hand, a plurality of 2 m through holes with a diameter of about 8 mm are arranged at equal intervals around the circumference at the bottom of the rotating side, and an annular hole with a diameter of about 0.5 to 1 mm is provided between the outermost edge of the rotating plate and the fixed ring. A minute gap 2n is provided.

A container 10 for storing the fluid that has fallen from the through hole 2a is fixed on the lower side of the rotary plate, and a discharge port 11 for the fluid is provided at one location on the circumference.

Further, in the space between the rotating plate 2 and the container 10, the rotating plate 2
On the lower surface of the outer periphery, there are a plurality of holes at equal intervals around the circumference, for example,
~Eight circulation vanes 12 are attached and rotate within the space as the rotary plate 2 rotates.

Further, in another embodiment of the present invention shown in FIG. 2, the rotary plate 2 is supported from below by a bearing 4a of a bearing box 4, and is rotated by the drive of the rotary shaft 3.

Next, the configurations of the fixed ring 1 and the rotary plate 2 will be explained in detail with reference to FIG.

The fixed ring 1 is of an annular shape installed with the axial direction in the vertical direction, and the diameter is widest at the middle part (hereinafter referred to as the middle part) lb in the height direction. The fixed ring l is attached to the middle part 1b.
The diameter of the lower part (hereinafter referred to as the lower part) 1C is slightly reduced downward, and the diameter of the upper part (hereinafter referred to as the upper part) 1a is reduced upward from the middle part. Therefore, the inner wall surface IA of the fixed ring l extends from the lower IC to the middle ib.
The diameter slightly expands towards the center, and the middle part 1b is approximately vertical.
It has a shape that decreases in diameter from the middle part 1b toward the upper part 1a,
Moreover, the longitudinal section of the inner wall surface LA is curved in a substantially concave shape.

The inner wall surface may be a straight line as shown in FIG.
A flange 25 is provided protruding from the outer circumferential surface of the middle portion lb of the fixed ring 1, and the flange 25 is placed on a flange 26 protruding from the outer periphery of the upper end of the container 10, and is fixed by a port 27.

The plate surface 2A of the rotary plate 2 has a shape whose diameter increases downward at the central portion 2a, is approximately horizontal at the intermediate portion 2b continuing from the central portion, and has an outer circumferential portion 2C continuing from the intermediate portion 2b. In this case, the diameter expands upward. The plate surface 2A is curved concavely as a whole, and the inner wall surface 1A of the fixed ring l and the plate surface 2A are connected to the fixed ring 1 and the rotary plate 2.
The surface is continuous and smooth except for a small gap 2n between the two.

A pointed cap 30 is attached to the central portion of the rotation @2, and is fixed by a port 31.

A shaft hole 32 is bored in the center of the rotating plate 2, and the upper end of the support block 34 is fitted into the shaft hole 32. The lower end of the port 31 is screwed into a piece 33 provided at the upper end of the support block 34.

Although not shown, liners are attached to the inner wall surface 1A of the fixed ring 1 and the side surface 2A of the rotary plate 2, respectively.

The container 10 is provided with an inlet 35 for introducing a gas such as air, and the bearing box 4 is cooled by introducing the gas. This will be explained next.

A large number of grinding media made of, for example, spherical poles are charged into the grinding chamber 20 in advance. First, the pulverized raw material prepared by mixing and stirring liquids such as water at a constant ratio is introduced into the apparatus through the input chute 8. This is a combination of the circular motion (arrow S) in which the grinding raw material and the grinding medium circulate between the inner wall surface 1A of the fixed ring 1 and the plate surface 2A as the rotary plate 2 rotates, and the rotational movement of the rotary plate 2 around its axis. A spiral movement (centrifugal flow) similar to spinning a rope is performed by the nn, and the pulverized raw material is ground or stripped by the nn.

That is, when the rotary plate 2 is rotated, the grinding medium is moved in the outer circumferential direction by centrifugal force, and this velocity energy causes it to crawl up the inner wall surface 1A of the fixed ring 1. When the climbing force becomes smaller than gravity, the grinding medium moves toward the outer circumferential direction due to the centrifugal force. and falls onto the plate surface 2A of the rotating plate 2.

The grinding medium that has moved onto the dish surface 2A is moved toward the fixed ring 1 again along this dish surface 2A.

Further, when the rotating plate 2 is rotated once, the grinding medium revolves in the circumferential direction at a speed slower than the rotational speed of the rotating plate 2. Therefore, as described above, the grinding medium is divided into the dish surface 2A and the inner wall surface IA.
In addition to the circular motion S in the vertical direction that circulates, it also performs the orbital motion that rotates around the axis of the rotary plate 2, and the combination of these two motions creates a spiral movement similar to tying a rope (centrifugal flow).
Do this.

In this way, the grinding medium moves up the inner wall surface 1A while maintaining its movement in the circumferential direction of the rotating plate 2. When the inner wall surface LA is fixed, the grinding medium moves up the circumference of the rotating plate 2. The composite speed of the directional speed (revolution speed) and the creeping speed of the grinding medium directly becomes the speed difference between the inner wall surface IA and the grinding medium. Therefore, the speed difference between the grinding medium and the inner wall surface IA becomes extremely large, and the grinding action of the grinding medium when moving on the inner wall surface IA becomes extremely strong.

Furthermore, since the grinding media that has separated from the inner wall surface IA and landed on the dish surface 2A smoothly rolls down along this dish surface 2A, the inner wall surface IA is Since the drive unit can convert the potential energy obtained during upward movement into kinetic energy in the radial direction, the energy once applied to the grinding medium can be effectively used for the peeling action without wasting it. . Furthermore, when descending along the dish surface 2A, the grinding media
Since it slides on the surface, grinding or peeling occurs even during this downward movement.

On the other hand, the solid-liquid two-phase fluid containing the fine powder thus crushed enters the container IO from the crushing chamber 20 via the through hole 2m,
Centrifugal force is applied by the action of the circulation vanes 12 that rotate with the rotation of the rotary plate, thereby forming a circulation flow that ascends through the minute gap 2n and returns to the crushing chamber 20 again. Therefore, the fluid forms two circulating flows: a circulating flow S in the grinding chamber 20 and a circulating flow passing through the container 10. Therefore, the grinding chamber 2
Compared to the case where there is only a circulating flow within 0, the mixing of the fluid and the raw material fine powder is further promoted by the second circulating flow by the circulating blades, and as a result, the mixing is more uniform, the grinding efficiency is improved, and the A product with a narrow particle size distribution and uniform particle size can be obtained.

The pulverization proceeds as described above, and after the pulverization is completed, the material is discharged from the outlet 11 of the container 10, completing one batch operation.

In addition, the weight ratio of fluid such as water and raw materials is water: raw material = 228
A ratio of water to raw material of 8:2 is appropriately selected in consideration of the pulverizability of the raw material and the particle size of the final product.

A subsequent wet cyclone, centrifugal classifier, etc. is used to classify particles in the fluid at the outlet.

[Effects of the Invention] As explained above, in the wet type centrifugal fluid milling apparatus of the present invention, the circulating flow of the fluid in the rotating dish can be created separately from the circulating flow in the rotating dish through the container. As a result, the fluid and the fine powder are mixed more uniformly, resulting in improved grinding efficiency and a product with uniform particles having a narrow particle size distribution.

[Brief explanation of drawings]

FIG. 1 is an overall longitudinal sectional view of an embodiment of the apparatus, and FIG. 2 is a longitudinal sectional view of essential parts showing another embodiment. 1...Fixed ring, 2...Rotating plate, 2m...Through hole, 2n...Minute gap,
1A...Inner wall surface, 2A...Dish surface, 3...
...Rotating shaft, 4...Bearing box, 8.
... Input chute, 9 ... Frame, 10
... Container, 11 ... Discharge port, 12 ... Circulation vane.

Claims (1)

[Claims] (1) A rotatable motor whose rotational axis is vertically oriented, has a flattened surface whose diameter expands downward at least in the central portion, and whose vertical cross section is concavely curved. It has a circular rotating plate and an inner wall surface whose diameter decreases upward at least in the upper part, and the vertical cross section of the inner wall surface is curved in a substantially concave shape, and is coaxially arranged around the rotating plate. and a stationary ring that is stationary, and the plate surface of the rotating plate and the inner wall surface of the fixed ring are formed into a continuous smooth surface except for a minute gap between the rotating plate and the fixed ring. This is a wet-type centrifugal fluid milling device, which has a through hole near the bottom of the rotary plate, and a hole on the lower surface of the outer periphery of the rotary plate for transferring a solid-liquid two-phase fluid containing powder of the material to be crushed. 1. A centrifugal fluid pulverizer, characterized in that a circulating blade is provided, and a container and a discharge port for the solid-liquid two-phase fluid are provided below the rotary plate.