JPH10118516A - Impact pneumatic pulverize - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an impact type pneumatic pulverizer whose pulverizing efficiency is improved. SOLUTION: This pneumatic pulverize is provided with an accelerating pipe 9 for conveying and accelerating powder by compressed air, a pulverizing chamber 7a communicating with an air outlet 9b installed at one end of the accelerating pipe 9, and an impact member 16 having an impact surface 17 for making the conveyed and accelerated powder impact on it to pulverize it and arranged in the pulverizing chamber 7a so that the impact surface 17 may be opposite to the air outlet 9b of the accelerating pipe 9. In this case, the impact surface 17 in the shape of a circular or polygonal plane is equally divided into plural regions 17a around the central point, and each region 17a is inclined so that difference in step between the regions 17a, 17a may be produced and also the impacted powder dispersed in all the circumferential directions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an impingement type air current pulverizer for pulverizing a powder such as a resin powder using compressed air.

[0002]

2. Description of the Related Art An impingement type air current pulverizer for pulverizing resin powder or the like using compressed air communicates with an acceleration tube for conveying and accelerating the powder by compressed air and an air outlet provided at one end of the acceleration tube. A crushing chamber, and a collision member disposed in the crushing chamber having a collision surface for colliding and pulverizing the powder conveyed and accelerated by the acceleration tube so that the collision surface faces the air outlet of the acceleration tube. It has.

[0003] As the collision member of such a collision-type airflow pulverizing apparatus, a collision member having a flat surface whose collision surface is perpendicular to the powder conveyance direction or a cone having a collision surface inclined with respect to the powder conveyance direction is used. A planar or spherical one or the like is used.

[0004]

In the case of the former collision member, since the colliding powder is reflected perpendicularly to the collision surface, the concentration of the powder in the vicinity of the collision surface is increased, thereby increasing the powder density. There is a problem that the collision force is reduced, and a problem that the secondary crushing in which the crushed powder is crushed by secondary collision with the inner surface of the crushing chamber is difficult to be performed.

[0005] In the case of the latter collision member, most of the colliding powder flows along the collision surface together with the airflow. Therefore, by setting the inclination angle of the collision surface to an appropriate angle, the former collision member and the collision member are separated. The powder concentration in the vicinity of the collision surface is relatively low and secondary pulverization is easy to be performed in comparison, but if the collision surface is inclined too much with respect to the powder conveyance direction, the impact force at the time of collision becomes small,
In addition, there is a problem that the grinding efficiency is reduced because the secondary grinding is not easily performed.

Further, in the case of the latter collision member, it is difficult to process the collision surface and the production cost is high. Further, since the collision surface is a curved surface, it cannot be constituted by sticking a chip or the like, and the collision surface cannot be formed. If worn, the entire collision member must be replaced, which causes a problem of high running cost.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an impingement-type airflow pulverizer which improves pulverization efficiency.

Another object of the present invention is to provide a collision-type airflow pulverizer that can be manufactured at low cost and can reduce running cost.

[0009]

Means for Solving the Problems To achieve the above object, an invention according to claim 1 is provided with an accelerating tube for conveying and accelerating powder by compressed air, and at one end of the accelerating tube. A pulverizing chamber communicating with an air outlet, and a collision surface for colliding and pulverizing the powder conveyed and accelerated by the accelerating tube, wherein the pulverizing chamber has a collision surface facing the air outlet of the accelerating tube. In the collision type air current pulverizer having a collision member disposed in the collision surface, the collision surface is equally divided into a plurality of regions around a center point of a circular or polygonal plane,
Each of the regions is inclined so that a step is generated between the regions and the colliding powder is dispersed in the entire circumferential direction.

[0010] The invention described in claim 2 is the same as the claim 1.
Wherein the collision member comprises a collision member main body and a plurality of flat chips which are attached to the collision member main body and form the respective regions.

The invention described in claim 3 is the same as the claim 2
Wherein each of the chips is attached to the collision member main body by screwing.

The invention described in claim 4 is the same as the claim 2.
Alternatively, in the invention according to claim 3, the main body of the collision member is made of a material having good thermal conductivity.

[0013] The invention described in claim 5 provides the invention according to claim 4.
In the invention described in (1), the collision member main body is hollow, and cooling fluid supply means for supplying a cooling fluid to the inside of the collision member main body is provided.

[0014] The invention according to claim 6 is the first invention.
The invention according to any one of claims to 5, wherein a radius is formed at an edge of each of the regions.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram of a collision-type airflow pulverizer according to an embodiment of the present invention, FIG. 2 is a plan view of a collision surface of a collision member, and FIG. 3 is a perspective view of the collision member.

This collision type air flow crusher is for crushing toner or the like used in a copying machine or an electrophotographic printer, and is disposed at an upper left portion of the apparatus main body 1 and the apparatus main body. 1, a powder feeder 2 for supplying a powder raw material, a compressor 3 connected to a lower part of the apparatus main body 1 for supplying compressed air to the apparatus main body 1, and a pulverizer connected to an upper part of the apparatus main body for pulverization. A blower 5 for sucking the powder into the bag filter 4.

The apparatus main body 1 has a cylindrical casing 6 whose upper and lower end faces are sealed. Inside the casing 6, there is provided a bottomed cylindrical inner cylinder 7 coaxially arranged with the casing 6, and powder supply between the outer surface of the inner cylinder 7 and the inner surface of the casing 6 is provided. An annular powder passage 8 through which the powder supplied by the machine 2 and the coarse powder classified by the classifying rotor 18 described later pass is formed. Inner cylinder 7
Has a pulverizing chamber 7a for pulverizing powder at a lower portion, and a large-diameter portion 7b having an enlarged diameter at an upper portion.

An accelerating tube 9 is attached to the center of the lower end surface of the inner cylinder 7 so as to project vertically downward, and the upper end of the accelerating tube 9 communicates with the pulverizing chamber 7a. A nozzle 10 is arranged below the accelerating tube 9 so as to be coaxial with an extension of the center line of the accelerating tube 9, and the lower end of the nozzle 10 is provided with air attached to the center of the lower end surface of the casing 6. It communicates with the supply pipe 11. The compressor 3 is connected to the air supply pipe 11.

A powder passage 8 is disposed below the inside of the casing 6 so as to surround the acceleration tube 9 and the upper part of the nozzle 10.
A funnel-shaped chute 12 is provided for guiding the powder raw material that has fallen into a suction port 9 a provided at the lower end of the acceleration tube 9. An annular chamber 13 communicating with the inside of the chute 12 is provided between the outer surface of the chute 12 and the inner surface of the casing 6.
Is formed on the lower outer surface of the casing 6, and the secondary air suction pipe 1 protrudes sideward and communicates with the chamber 13.
4 is attached. A pressure gauge (not shown) for monitoring the air pressure inside the chamber 13 is attached to a lower outer surface of the casing 6.

A support member 15 is horizontally mounted substantially at the center of the crushing chamber 7a of the inner cylinder 7, and has a columnar collision member 16 coaxially with the crushing chamber 7a and vertically downward. It is supported so that it hangs down. The collision member 16 has a collision surface 17 on the lower end surface facing the air outlet 9 b provided at the upper end of the acceleration tube 9 for colliding and pulverizing the powder conveyed and accelerated by the acceleration tube 9. I have. As shown in FIG. 2, the collision surface 17 has a circular shape in plan view.

Above the inside of the casing 6, an inner cylinder 7
A classifying rotor 18 is disposed near the upper end opening of the large-diameter portion 7b and is coaxial with an extension of the center line of the inner cylinder 7. A motor 19 for rotating around is provided. At the upper part of the casing 6, a discharge pipe 20 protruding laterally and having one end communicating with the inside of the casing 6 is attached, and the bag filter 4 and the blower 5 are connected to the discharge pipe 20. .

The collision member 16 has a columnar collision member main body 21 having an enlarged lower end portion, and a fan-shaped region 17 attached to the lower end surface of the collision member main body 21 to form the collision surface 17.
a (see FIGS. 2 and 3) four flat chips 22
It consists of The tip 22 is formed by equally dividing a disk made of a wear-resistant material such as cemented carbide or ceramic into four fan-shaped portions around a center point. On the other hand, the collision member main body 21 is made of steel, copper, or the like having good thermal conductivity, is formed by cutting, forging, or the like, and has four fan-shaped pedestals 21a for attaching the chip 22 to the lower end surface. The chip 22 is fixed to the pedestal 21a by bonding or screwing. In addition, when the screw 22 is used, the tip 22 can be replaced when it becomes worn, so that the running cost can be reduced.

The pedestal 21a arranges the chips 22 at an angular interval of 90 ° around the center line L so as to form a disk when viewed in the direction of the center line L of the collision member main body 21. A line M whose right edge of the chip 22 is orthogonal to the center line L and which is orthogonal to the center line L of the left edge of the chip 22
Angle θ1 toward the collision member body 21 with respect to
It is supported at 40 ° (20 ° in the illustrated example).

The classifying rotor 18 is disposed so as to be vertically opposed to a ring-shaped upper end wall 23 which is disposed horizontally, and to face the upper end wall 213 vertically. And a circular lower end wall 24 to which a rotating shaft 24a is fixedly attached, and is disposed at equal angular intervals around the rotating shaft 24a, extends vertically, and extends vertically.
And a plurality of plate-like blades 25 for connecting the peripheral portions of the base plates 3 and 24 to each other.

Next, the operation of the impingement type air current pulverizer constructed as described above will be described. The powder raw material supplied to the inside of the casing 6 by the powder supply device 2 falls in the powder passage 8, and the suction port 9 a at the lower end of the acceleration tube 9 is moved by the chute 12.
Will be guided to. On the other hand, compressed air is supplied to the nozzle 10 from the compressor 3 via the air supply pipe 11,
The compressed air ejected from the nozzle 10 flows into the acceleration tube 9. As a result, the air near the suction port 9a of the acceleration tube 9 is sucked into the acceleration tube 9, so that the powder material is
Flows into.

The inside of the casing 6 is in a negative pressure state by the blower 5, and the pressure in the annular chamber 13 around the chute 12 is lower than the atmospheric pressure. for that reason,
Air flows into the chamber 13 via the suction pipe 14, and this air flow flows into the chute 12 to promote the flow of the powder raw material into the acceleration pipe 9. When the powder concentration in the vicinity of the suction port 9a of the acceleration tube 9 increases, the flow of the air flow is hindered.
The inside of the chamber 13 becomes close to the atmospheric pressure. Therefore, by checking the air pressure inside the chamber 13 with a pressure gauge, the powder concentration in the vicinity of the suction port 9a of the acceleration tube 9 can be known. The flow can be smooth.

Since the air flowing into the accelerating tube 9 is accelerated, the powder flowing into the accelerating tube 9 is also accelerated, and the powder is ejected from the air outlet 9 b of the accelerating tube 9, and the collision surface 17 of the collision member 16. Violently crushed and crushed. The pulverized powder is dispersed over the entire circumferential direction of the collision surface 17, and secondary-collides with the inner surface of the peripheral wall of the pulverizing chamber 7a to be further pulverized. A part of the powder colliding with the collision surface 17 also collides with the right side of the chip 22 and is crushed, and then collides with the inner surface of the peripheral wall of the crushing chamber 7a to be further crushed. FIG. 4 is a schematic diagram showing the trajectory of the powder that has secondarily collided with the inner surface of the crushing chamber 7a. This trajectory
This is obtained by applying a paint to the inner surface of the peripheral wall of the pulverizing chamber 7a, operating the apparatus for an appropriate period of time, and then developing the peripheral wall of the pulverizing chamber 7a to check the peeling state of the paint.

The powder colliding with the collision surface 17 is substantially the same as the collision surface 1
Since the powder flows along the region 17a on the surface of the chip 22 and the right side surface of the chip 22, the trajectory of the secondary collision of the powder is zigzag along the periphery of the region 17a and the side edge of the right side surface of the chip 22. Shape line. On the other hand, when a collision member having the same diameter as the collision surface of the collision member and having a conical or spherical collision surface is used, since there is no step in the collision surface, the trajectory of the secondary collision of the powder is As shown in FIG. Therefore, according to the present invention, since the trajectory of the secondary collision is lengthened by the step between the regions constituting the collision surface, the powder can be more efficiently dispersed and the powder can be efficiently pulverized. .

The pulverized powder rises on the rising airflow in the inner cylinder 7 and is agitated by the classifying rotor 18 to give a centrifugal force radially outward of the classifying rotor 18. The coarse powder having a large particle diameter flows outward in the radial direction of the classification rotor 18 due to a large centrifugal force, and flows into the powder passage 8. Then, the coarse powder falls in the powder passage 8 and flows into the accelerating tube 9 again to perform the above-described pulverizing step. Further, since the fine powder having a small particle diameter has a small centrifugal force, the blades 25, 2
The fluid flows into the classifying rotor 18 from the space between the five and passes through a circular hole provided in the upper end wall 23 and flows into the discharge pipe 20.

The fine powder flowing into the discharge pipe 20 is
And flows into the bag filter 4 through a pipe connected to the filter. The fine powder is separated from the airflow by the bag filter 4 and stored in the bag filter 4. Thereafter, the fine powder is taken out of the bag filter 4 and collected. The diameter of the powder classified by the classifying rotor 18 can be freely set by changing the number of revolutions of the classifying rotor 18.

It should be noted that the present invention is not limited to the above embodiment, and various changes can be made. For example, the shape of the collision surface of the collision member may be polygonal. The number of divisions of the collision surface can be set to an arbitrary number as long as it is two or more. Further, a radius may be formed at an edge of each region constituting the collision surface. By doing so, the flow of the air current becomes smooth, and the pulverization efficiency is improved. Further, the inclination angle of the region constituting the collision surface can be set to any angle within the range of 5 ° to 40 °. Note that if the inclination angle is large, the impact force at the time of collision decreases, so the inclination angle is preferably within 30 °.

In the above embodiment, only one side edge of the region constituting the collision surface is inclined with respect to a line orthogonal to the center line of the collision member. However, as shown in FIGS.
The other side edge of the region 17 a may also be inclined with respect to a line M orthogonal to the center line L of the collision member 16. In this case, FIG.
When θ1> θ2, the collision surface is sharpened toward the center point, so that the powder is easily dispersed in all circumferential directions, the air flow is smooth, and the pulverization efficiency is improved. When θ1 <θ2 as shown in FIG. 7, the collision surface is depressed toward the center point. When the inclination angles of the regions 17a are equal, θ2 needs to be larger than 0 ° in order to generate a step between the adjacent regions 17a, 17a.

Further, the collision member may be rotated around the center line. With this configuration, the powder uniformly collides with each region of the collision surface, so that wear of each region can be equalized. Further, the collision surface may be a curved surface.

Further, since the temperature of the collision surface rises due to frictional heat generated by the collision of the powder, the powder may be fused to the collision surface and the pulverization efficiency may decrease. In the present embodiment, the collision member main body is made of a material having good thermal conductivity so as to suppress a rise in the temperature of the collision surface.However, the collision member main body is hollow, and a cooling fluid is provided inside the collision member main body. By providing the cooling fluid supply means for supplying, it is possible to more positively suppress a rise in the temperature of the collision surface, and further reduce a decrease in the pulverization efficiency.

Examples of the material to be pulverized suitable for the pulverizing apparatus of the present invention include, for example, toner, resin, wax, paint, other weakly heat-resistant substances, mica, talc, ceramics, silica gel, abrasives and the like. Materials.

[0036]

As described above, according to the present invention,
The trajectory of the secondary collision of the powder becomes longer due to the step generated between the plurality of regions constituting the collision surface, and a part of the powder colliding with the collision surface collides with the step between the regions, and further. Since the powder is pulverized, the powder can be pulverized efficiently.

According to the second aspect, since the collision surface is constituted by a plurality of flat chips, it is easy to process and can be manufactured at low cost. Also, running costs can be reduced.

According to the third aspect, each tip is attached to the collision member main body by screwing.
Since only the tip needs to be replaced when the collision surface is worn, the running cost can be further reduced.

According to the fourth aspect, since the collision member body is made of a material having good thermal conductivity, the temperature rise of the collision surface can be suppressed, and the powder is prevented from being fused to the collision surface. As a result, a decrease in grinding efficiency can be reduced.

According to the fifth aspect, by injecting a cooling fluid into the interior of the collision member main body, the temperature rise of the collision surface can be more positively suppressed, so that the reduction in the pulverization efficiency can be further reduced. it can.

According to the sixth aspect, since the radius of each of the regions constituting the collision surface is formed, the flow of the air current becomes smooth, and the pulverization efficiency is further improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a collision type airflow pulverizer according to an embodiment of the present invention.

FIG. 2 is a plan view of a collision surface of a collision member.

FIG. 3 is a perspective view of a collision member.

FIG. 4 is a schematic view showing a locus of a secondary collision of powder.

FIG. 5 is a schematic diagram showing a trajectory of a secondary collision of powder in a conventional collision-type airflow pulverizer.

FIG. 6 is a perspective view showing another embodiment of the present invention.

FIG. 7 is a perspective view showing another embodiment of the present invention.

[Explanation of symbols]

 7a grinding chamber 9 acceleration tube 9b air outlet 16 collision member 17 collision surface 17a area

Claims (6)

[Claims] An acceleration tube for conveying and accelerating powder by compressed air, a grinding chamber communicated with an air outlet provided at one end of the acceleration tube, and a powder conveyed and accelerated by the acceleration tube collide with the acceleration tube. And a collision member disposed in the grinding chamber such that the collision surface faces the air outlet of the acceleration tube, and the collision surface has a collision surface. A circular or polygonal plane is equally divided into a plurality of regions around the center point, and the respective regions are inclined so that a step is generated between the regions and the colliding powder is dispersed in the entire circumferential direction. An impingement airflow pulverizer characterized by the following: 2. The collision member according to claim 1, wherein the collision member includes a collision member main body and a plurality of flat chips attached to the collision member main body to form the respective regions.
2. The collision type air flow pulverizer according to item 1. 3. The chip according to claim 2, wherein each of the chips is attached to the collision member main body by screwing.
2. The collision type air flow pulverizer according to item 1. 4. The collision-type airflow pulverizer according to claim 2, wherein the collision member main body is made of a material having good thermal conductivity. 5. The impingement airflow pulverizer according to claim 4, wherein the collision member main body is hollow, and cooling fluid supply means for supplying a cooling fluid is provided inside the collision member main body. apparatus. 6. The impingement type airflow pulverizer according to claim 1, wherein a radius is formed at an edge of each of the regions.