JPH08103684A - Impact type pneumatic pulverizer - Google Patents

Abstract

PURPOSE: To efficiently pulverize a powder raw material by providing an impact member opposite to the opened surface of an outlet of an accelerating pipe in a pulverizing chamber and constituting a specified part of the impact surface of the impact member of a special member. CONSTITUTION: An accelerating pipe 3 for transferring and accelerating a material to be pulverized by high pressure gas and a pulverizing chamber 8 for finely pulverizing the material to be pulverized are arranged. In the pulverizing chamber 8, an impact member 4 is arranged opposite to the opened surface of an outlet 13 of the accelerating pipe 3. The central part of the impact surface on the impact member 4 where severest impact takes place is constituted of a special member having excellent abrasion resistance and is made removable. In this way, when the special material is worn out, only the worn material may be replaced, and the powder raw material is efficiently pulverized and the long life of the impact member 4 is secured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a collision type air flow crusher for crushing powder raw materials using a jet air flow (high pressure gas).

[0002]

2. Description of the Related Art Conventionally, a collision type air flow crusher using a jet air flow puts a powder raw material on a jet air flow to form a particle mixed air flow and jets it from an outlet of an accelerating pipe. The powder material is crushed by the collision force of the collision member provided in the above.
An example of the collision type airflow crusher will be described with reference to FIG.

The collision type air flow pulverizer shown in FIG. 1 is provided with a collision member 4 facing the outlet 13 of the accelerating pipe 3 to which the high pressure gas supply nozzle 2 is connected, and is accelerated by the flow of the high pressure gas supplied to the accelerating pipe 3. An object to be ground is introduced into the accelerating pipe 3 from the object to be ground supply port 1 which is connected to the middle of the pipe 3, and the material is jetted together with high-pressure gas to collide with the collision surface of the collision member 4, and is ground by the impact. It is something that I have done.

In such a collision type air flow crusher, the powder to be crushed constantly collides with each device element violently.
Wear deterioration of each device element cannot be avoided. In particular,
Figure 1 shows the locations where heavy load is applied and wear is severe.
In the above apparatus, the collision surface of the collision member 4 is a collision surface of the raw material. When these members 4 are consumed due to wear, the grinding efficiency is reduced, and worn impurities are mixed in the product, which is not preferable.

For this reason, a material such as alumina-based ceramics is used for the collision member to prevent abrasion, but in recent years,
When a harder material is required to be crushed, or when finer particles are to be obtained, even alumina-based ceramics are subject to severe wear and the replacement frequency becomes frequent. In such a case, it is necessary to recreate the collision member,
It is costly and the delivery time for ceramic parts is very long. Therefore, there is a demand for a collision type airflow crusher that achieves abrasion resistance and can be manufactured inexpensively and stably.

[0006]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art and to provide a novel collision type air flow crusher capable of efficiently crushing powder raw materials. is there.

[0007]

The above object can be achieved by the present invention described below. That is, the present invention has an accelerating tube for conveying and accelerating the object to be crushed by the high-pressure gas, and a crushing chamber for finely crushing the object to be crushed. In the collision type airflow crusher having a collision member provided opposite to the collision type airflow crusher, a specific portion of the collision surface on the collision member is configured by another member.

[0008]

As shown in FIG. 3, the collision member is constructed such that the center portion of the collision surface can be detached as a separate member, so that in the conventional case, when the abrasion member is worn, the entire collision member must be replaced.
According to the present invention, it is only necessary to replace a portion that is extremely worn, the cost can be reduced, and the life of the collision member can be extended.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail with reference to the drawings. In the crusher of FIG. 1, the acceleration tube 3
The powder raw material ejected from is crushed on the collision surface of the collision member 4 facing each other. In the present invention, the inner wall of the crushing chamber is made of transparent acrylic in advance, and the location where the powder collides is verified,
After that, the object of the present invention is achieved by configuring the portion where the most violent collision is occurring as another member having excellent wear resistance.

That is, when the collision surface as shown in FIG. 1 is formed in a plane shape perpendicular to the powder flow ejected from the acceleration tube,
It was confirmed that there was a violent collision near the center of the collision surface, and when actually used for a long time, the center of the collision surface became scooped out. Therefore, in the present invention, the collision member is shown in FIG.
As shown in, the center of the collision surface is detachable as a separate member. With such a configuration, in the past, when the wear occurred, all the collision members were replaced, but
According to the present invention, it is only necessary to replace a portion that is extremely worn, the cost can be reduced, and the life of the collision member can be extended.

The present invention is not limited to the configuration and shape of FIG. That is, as the shape of the collision member, various shapes as shown in FIG. 2 can be used, and may be appropriately selected depending on the characteristics of the pulverized raw material to be pulverized, the desired particle size and the like. At that time, depending on the shape of the collision member used,
The collision point of the collision member may be checked in advance, and the location where the collision is most intense may be formed by another member having excellent wear resistance.

In order to further improve the grinding efficiency,
2 (e) is a projecting central portion 14 projecting on the collision surface, and a primary crushed material crushed at the projecting central portion around the projecting central portion is further crushed by collision. The shape having the outer peripheral collision surface 15 is preferable. By providing a cone-shaped projection 14 having a central portion protruding on the collision surface of the collision member 4, the solid-gas mixture flow of the pulverization raw material and the compressed gas ejected from the acceleration tube 2 undergoes primary pulverization on the surface of the protrusion 14. Further, after secondary crushing on the outer peripheral collision surface 15, tertiary crushing is performed on the side wall of the crushing chamber.

At this time, the apex angle α (°) of the projecting central portion 14 projecting to the collision surface of the collision member 4 and the inclination angle β (°) of the outer peripheral collision surface 15 with respect to the vertical plane of the central axis of the acceleration tube. However, when 0 <α <90 and β> 0 30 ≦ α + 2β ≦ 90 are satisfied, the grinding is performed very efficiently. still,
In this shape, the protruding central portion 14 and the outer peripheral collision surface 15
The shape is not particularly limited, and may be appropriately selected from a conical shape, a pyramidal shape, and the like.

In the collision member having the shape shown in FIG. 2 (e), as a result of the preliminary examination, particularly in a portion where the powder collides violently, the protrusion center portion 14 where the primary crushing is performed and the protrusion center portion bottom portion of the outer peripheral collision surface 15 are formed. The area was within 20 mm. Therefore, as shown in FIG. 4, it is preferable that specific portions of the projecting central portion 14 and the outer peripheral collision surface 15 be formed as separate members having excellent wear resistance.
By doing so, when the collision member is worn, stable production can be achieved by replacing only the worn member even after long-term use. The structure of the crusher itself is not limited to that shown in FIG. 1, and FIG. 5 is illustrated as a collision-type air flow crusher having another preferable structure.

Explaining the crusher of FIG. 5, it has an accelerating tube 21 for conveying and accelerating an object to be crushed by high-pressure gas, and a collision member 30 having a collision surface provided facing the accelerating tube. The accelerating pipe 21 has a Laval nozzle shape, a high pressure gas supply nozzle 23 is arranged upstream of the throat part of the accelerating pipe 21, and an object to be crushed is provided between an outer wall of the high pressure gas supply nozzle and an inner wall of the throat part 22, Further, the crushing chamber connected to the outlet of the accelerating tube 21 has a circular cross section in the axial direction.

The crushed material supplied from the crushed material supply cylinder 25 is coaxial with the inner wall of the accelerating tube throat portion 22 of the accelerating tube 21 whose central axis is arranged in the vertical direction and the center of the accelerating tube 21. It reaches the crushed material supply port 24 formed between the upper wall of the high pressure gas supply nozzle 23 and the outer wall. On the other hand, the high-pressure gas is introduced from the high-pressure gas supply port 26, passes through the high-pressure gas chamber 27, passes through one or more high-pressure gas introduction pipes 28, and passes through the high-pressure gas supply nozzle 23 to the acceleration pipe outlet 2.
Ejects while expanding rapidly in 9 directions. At this time, due to the ejector effect generated in the vicinity of the accelerating pipe throat portion 22, the crushed substance is sucked toward the accelerating pipe outlet 29 from the crushed substance supply port 24 while being entrained in the gas coexisting therewith. , The acceleration tube throat part 22 is rapidly accelerated while being uniformly mixed with the high-pressure gas, and the acceleration tube outlet 2
The collision surface of the collision member 30 arranged to face 9 is collided and crushed in a state of a uniform solid-gas mixture air flow with no uneven dust concentration.

As the shape of the collision member, various shapes shown in FIG. 2 can be used. Particularly, the shape having a high crushing efficiency is shown in FIG. 2 (e) like the crusher of FIG. Is the shape of. In that case, more preferable ranges of α and β are as described above. The shape of the crushing chamber is not limited to the shapes shown in FIGS. 1 and 5, and may be set appropriately, and the shape of the crushing chamber inner wall may be selected in accordance therewith.

Comparing the collision type air flow pulverizers of FIGS. 1 and 5, the pulverizer of FIG. 5 disperses the substance to be pulverized uniformly in the high-pressure air stream without uneven concentration of dust. Therefore, the object to be crushed collides with the collision member more efficiently,
The crushing efficiency can be improved. That is, in the crusher of FIG. 5, compared with the crusher of FIG. 1, the mixed flow of high-pressure air and powder can be made to collide against the opposing collision member without slowing down the velocity, and therefore the crushing efficiency is improved and the collision is improved. The degree of wear of the members is also higher than that of the crusher shown in FIG. Therefore, it is more effective to use the member proposed in the present invention.

Various materials such as ceramics and cemented carbide can be used as the material preferably used as the specific member having excellent wear resistance of the present invention, and the silicon carbide ceramic sintered body is particularly preferably used. In that case, a silicon carbide ceramic sintered body is used in a specific place where wear is severe, and alumina ceramics are preferably used in other places.

The collision type airflow crusher of the present invention is preferably used when producing a toner for developing an electrostatic charge image. Although various performances are required for the toner used in the image forming method by electrophotography, what is particularly desired in recent years is to realize higher quality and higher definition images. As one of the means, it is desired to make the average particle diameter (weight average diameter) of the toner smaller. In particular, it is required to finely pulverize the toner so that the average particle diameter is 8 μm or less. In order to pulverize the particles into smaller pieces, in the case of a collision type air flow pulverizer, it is important to make the crushing raw material collide with the collision member more strongly and efficiently. In that case, the wear of the collision member progresses faster than before, so that it is very effective to use the collision type airflow crusher of the present invention. Further, the toner for developing an electrostatic charge image may contain magnetic powder, and in such a case, since the progress of wear is more rapid and the collision member is frequently replaced, the collision-type airflow crusher of the present invention. Can be used more effectively.

[0021]

As is clear from the above description, according to the collision type airflow crusher of the present invention, the crushing device is constituted by forming a specific portion of the collision member as a separate member having excellent abrasion resistance. It has excellent abrasion resistance, long life, cost reduction, and more stable production. In particular, the present invention is effective in the case of producing a powder such as a toner for developing an electrostatic charge image, which is highly abradable and requires a strict particle size stability.

[0022]

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a collision type airflow crusher for explaining the present invention.

FIG. 2 is a diagram schematically showing a collision surface shape of a collision member used in the present invention.

FIG. 3 is a schematic cross-sectional view for explaining the configuration of a collision member used in the present invention in more detail.

FIG. 4 is a schematic cross-sectional view for explaining the configuration of another collision member used in the present invention in more detail.

FIG. 5 is a schematic cross-sectional view of another collision type airflow crusher for explaining the present invention.

[0023]

[Explanation of symbols]

 1 ... Object to be ground supply port 2 ... High pressure gas supply nozzle 3 ... Accelerator tube 4 ... Collision member 5 ... Discharge port 6 ... Grinding chamber wall 8 ... Grinding chamber 13 ... Acceleration tube outlet 14 ... Protruding central part 15 ... Outer peripheral collision surface 21 ... Accelerating tube 22 ... Accelerating tube throat section 23 ... High pressure gas supply nozzle 24 ... Grinding object supply port 25 ... Grinding object supply cylinder 26 ... High pressure gas supply Mouth 27 ...... High-pressure gas chamber 28 ...... High-pressure gas inlet pipe 29 ...... Acceleration pipe outlet 30 …… Collision member 32 …… Crushing chamber inner wall 33 …… Crushed material discharge port 34 …… Crushing chamber

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshinori Tsuji 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Satoshi Mitsumura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Within the corporation

Claims (4)

[Claims] 1. An accelerating tube for conveying and accelerating an object to be crushed by a high-pressure gas, and a crushing chamber for finely crushing the object to be crushed. A collision-type airflow crusher having a collision member provided facing each other, wherein a specific portion of a collision surface on the collision member is configured by another member. 2. A collision member for crushing a protruding center portion protruding on the collision surface of the collision member, and a crushed material crushed in the protruding center portion around the protruding center portion by further collision. The collision type airflow crusher according to claim 1, which has an outer peripheral collision surface. 3. When the apex angle of the projecting central portion projecting on the collision surface of the collision member is α (°) and the inclination angle of the outer peripheral collision surface with respect to the vertical plane of the central axis of the crushing nozzle is β (°). ,
The collision type airflow crusher according to claim 2, wherein the α and the β satisfy the following formulas 0 <α <90, β> 0 30 ≦ α + 2β ≦ 90. 4. The collision type airflow crusher according to claim 2, wherein a portion within 20 mm from the protruding central portion and / or the protruding central portion bottom portion of the outer peripheral collision surface is configured as a separate member.