JPH0360749A - Collision type air grinder - Google Patents

Abstract

PURPOSE:To efficiently grind powder contg. resin and substance having tackiness by beating the powder of a raw material on a collision plate by compressed air co grind it and allowing the ground raw material to flow along the guide part of the collision place and allowing this ground raw material to secondarily collide against the wall of a grinding chamber. CONSTITUTION:An acceleration pipe 3 for carrying and accelerating powder by high-pressure gas is provided in a grinding chamber. A collision plate 4 for grinding powder ejected from the acceleration pipe 3 by impulsive force is provided oppositely to the output of the acceleration pipe 3 in the grinding chamber. A projecting part is provided to the center of the surface of the collision place 4 and thereby powder flown together with the high pressure air from the acceleration pipe 3 is dispersed to the other direction. Furthermore, a guide part is provided to the edge side part of the collision plate 4. The flow direction of flown powder is regulated by this guide part. Thereby the flown powder is allowed to efficiently and secondarily collide against the wall 6 of the grinding chamber without drastically lowering kinetic energy. As a result, powder incorporating resin or substance having tackiness efficiently is ground without causing generation of welding, an aggregate and coarse grains.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an impingement type air flow crusher using a jet stream (high pressure gas).

[Background Art] A collision-type air-flow crusher using a jet stream places raw material powder on a jet stream, causes it to collide with a collision plate, and then
It is intended to be crushed by j'Jl force.

Conventionally, as shown in FIGS. 7 and 8, the collision plate used in such a crusher is a flat plate that is perpendicular to or inclined at 45 degrees to the jet stream direction, that is, the acceleration tube, on which the raw material powder is placed. I've been exposed to it.

To further explain based on the state diagram in FIG. 7, the coarse raw material powder from the classifier is supplied to the acceleration tube 3 from the input port 1,
The raw material powder is struck against the collision plate 4 by the jet stream blown out from the nozzle 2, is pulverized by the impact force, and is discharged from the system through the discharge port 5. The same applies to the case of FIG. In addition, FIG. 2 shows B- in FIGS. 7 and 8.
A cross-sectional view taken along line B' is shown.

However, in the above-mentioned conventional example, the collision plate is flat and is perpendicular or inclined at 45 degrees with respect to the acceleration tube, and therefore has the following drawbacks.

(1) If the angle of the collision plate is perpendicular to the accelerator tube, when resin or sticky materials are crushed, the local heat generated at the time of collision will generate fusion, agglomerates, coarse particles, etc., and the equipment will be damaged. This makes stable operation difficult and causes a decrease in crushing capacity.

Therefore, it cannot be used above a certain dust concentration.

(2) If the angle of the collision plate is inclined at 45 degrees with respect to the acceleration tube, the above-mentioned drawbacks will be less likely when crushing resin or sticky materials. However, the impact force used for crushing during collision is small, and the crushing capacity is 1/2 to 1/2 that of a right-angled collision plate.
The ability drops to /1.5.

[Object of the Invention] The object of the present invention is to solve the above-mentioned problems and to process powders containing resins and adhesives without causing fusion, agglomerates, or coarse particles. The purpose of the present invention is to provide a grinder that grinds efficiently.

[Summary of the Invention] That is, the present invention provides an acceleration tube that conveys and accelerates powder using high-pressure gas, and a collision plate that crushes the powder ejected from the acceleration tube by impact force, which is arranged opposite to the outlet of the acceleration tube. In a collision type airflow crusher installed in a crushing chamber, the powder is dispersed in substantially the entire circumferential direction from the collision plate surface, so that the powder efficiently collides with the opposing wall of the crushing chamber, and is crushed. In this way, the collision plate has a convex portion at the center of the collision plate surface, and an edge thereof has a guide portion formed of a concave curved surface.

[Detailed Description of the Invention] According to the present invention, in order to solve the problem of deterioration in crushing ability due to fusion, agglomerates, and coarse particles that occur when resins and sticky materials are crushed, Figure 2, Figure 3, Figure 4,
It was shaped as shown in FIGS. 5 and 6.

By doing this, when resin or sticky materials are crushed, fusion, agglomerates, and coarse particles that occur when the angle of the collision plate is 90 degrees to the accelerator tube will not occur, and the dust concentration during crushing will be reduced. It was possible to rise.

Furthermore, by using such a collision plate, it has become possible to cause the powder that collides with the collision plate and is crushed and bounced back with good dispersion to collide with the crushing chamber for a secondary collision, thereby further increasing the crushing efficiency. . In addition, by limiting the distance between the accelerating tube and the collision plate and the distance between the collision plate and the crushing chamber wall, it is possible to crush by more efficient secondary collision, and the angle of the collision plate is 90" with respect to the accelerating tube. The crushing capacity was substantially improved by 20 to 70% compared to that of the previous example.

Due to the presence of the central convex portion, the powder and air injected from the accelerating tube are quickly dispersed in the entire circumferential direction, making it difficult for fusion to occur and achieving efficient pulverization. The convex portion may have any shape as long as it achieves the above purpose, and the first
The present invention is not limited to those shown in FIGS.

The edge part, in combination with the above-mentioned convex part, has an inclination that is not perpendicular to the injection direction of the accelerator tube, so that the kinetic energy of the powder and air dispersed in the entire circumferential direction at the center is not significantly reduced. to efficiently collide with the wall of the grinding chamber,
Even more efficient pulverization becomes possible. To this end, it is desirable that the edge be set at an angle of 95° to 135° with respect to the injection direction of the injection nozzle, more preferably 100° to 13°.
More favorable results are obtained at 0°. As the angle approaches 90', fusion tends to occur, and as the angle approaches 135°, the impact when directly colliding with the collision plate becomes smaller, resulting in a decrease in processing capacity. are selected.

The effect of the present invention is more effective as the target particle size of the powder to be crushed becomes finer, and remarkable effects are obtained when the particle size is 20μ or less, more preferably 12μ or less, and even more preferably 8μ or less.

Also, when the edge section is viewed from a cross section, this slope may be a straight line, but it is better to use a concave curved surface that falls within the above angle to limit the angle of impact on the crushing chamber within the range of 95° to 135°. , a more favorable effect can be obtained.

[Example] Figures 1, 2, and 3 show the first example of the present invention, and Figure 1 best represents the characteristics of the raw material powder pulverization of the present invention. FIG. 2 is a state diagram, and FIG.
FIG.

In Fig. 1, 1 is the powder raw material input port to the crusher, 2 is the compressed air supply nozzle used when pulverizing the powder raw material, 3 is the acceleration tube that accelerates the powder with compressed air, and 4 is the acceleration tube outlet 5 is a discharge port for discharging the crushed powder and air, and 6 is a wall of the crushing chamber. Further, FIG. 3 is a sectional view showing the shape of the collision plate 4. As shown in FIG.

Here, 100 parts by weight of styrene-butyl acrylate resin 60 parts by weight of magnetite 2 parts by weight of low molecular weight polyethylene 2 parts by weight of negative charge control agent After that, it is cooled and solidified to a thickness of 100 to 1000μ with a hammer mill.
The raw material powder was obtained by coarsely pulverizing the powder into particles.

When the raw material powder is supplied from the input port 1, the raw material powder is struck against the collision plate 4 by the compressed air blown out from the nozzle 2, and is pulverized by the impact force. At the same time, this collision plate 4 has a convex shape in the center, and the raw material powder collides with it and flows along a guide part constituted by a smooth curved surface from the center toward the edge, facing the crushing chamber wall. 6 and is further shattered there.

The pulverized raw material powder is smoothly conveyed to the classifier through the discharge port 5, the fine powder is removed as a product, and the coarse powder is fed back into the classifier from the input port 1 together with the raw material powder.

When the collision plate 4 has the shape shown in FIG. 3 in this way, the raw material powder that collides with it is dispersed in the entire circumferential direction, bounces off, and secondarily collides with the opposing wall of the crushing chamber. As a result, the dust concentration near the collision plate does not increase, and fusion, agglomerates, and coarse particles do not occur, so the pulverization efficiency is not inferior, and a product with a sharp particle size distribution can be obtained, and the powder capacity is was confirmed to improve.

Embodiment 2 FIG. 4 shows the shape of a collision plate according to a second embodiment of the present invention, which is a collision plate having an eccentric convex portion. When the toner material used in Example 1 was crushed using this collision plate in the same manner as in Example 1, the same effects as in Example 1 were obtained.

Example 3 FIG. 5 shows a collision plate with an oblique convex shape showing a third example of the present invention. Using this collision plate, the toner material used in Example 1 was crushed in the same manner as in Example 1. Although the crushing ability was slightly inferior to that of Example 1, similar results to those of Example 2 were obtained.

XWari 1 FIG. 6 shows a collision plate having a spherical convex portion showing a fourth embodiment of the present invention, and using this collision plate, the toner material used in Example 1 can be prepared in the same manner as in Example 1. When the material was pulverized, since the convex portion had a spherical shape when it collided with the collision plate surface, the impact force was weakened and the pulverization ability was significantly reduced. Therefore, it is preferable for the collision plate surface to have a shape as in Example 1 rather than one in which the convex portion is spherical.

Comparative Example 1 When the toner material used in Example 1 was pulverized in the same manner as in Example 1 using a flat plate type collision plate perpendicular to the conventional acceleration tube 3 as shown in FIG. 10 ingredients
The crushing ability to reduce the particle size to μm was 0.0 mm compared to Example 1.
It decreased by 7 times.

Comparative Example 2 When the toner material used in Example 1 was pulverized in the same manner as in Example 1 using a flat plate type collision plate that was angled at 45 degrees with respect to the conventional acceleration tube 3 as shown in FIG. The crushing ability is lower than that of Comparative Example 1 because the impact force becomes weaker when colliding with the plate surface.

Each side mentioned above is listed in the table below.

(1) - Processing capacity 1 is the limit at which fused materials will occur if processing is performed faster than this.

As explained above, the shape of the collision plate is such that the center has a convex portion with a curved surface or a similar shape, and the edges have a concave curved surface or a guide portion with a similar shape to prevent fusion during raw material crushing. Prevents the generation of aggregates, coarse particles, etc.
This enables stable operation of the device and also maintains strong impact force until a secondary collision occurs. Therefore, the conventional crushing capacity has been increased to 20
It can be improved by ~70%. Furthermore, similar results were obtained when the collision plate was not only cylindrical but also polygonal.

[Brief explanation of drawings]

1 and 2 show examples of the present invention, FIG. 1 is a state diagram that best represents the characteristics of the raw material powder pulverization of the present invention, and FIG. 2 is a diagram showing A-A in FIG. ' line and Figures 7 and 8
It is a sectional view taken along the line BB' in the figure. Figures 3 to 6 show embodiments of the present invention, in which Figure 3 shows a convex collision plate with a smooth curved surface, Figure 4 shows an eccentric convex collision plate with the apex of the convex part eccentric; FIG. 5 is an explanatory diagram of an impingement plate having a convex oblique surface that is inclined with respect to the acceleration tube, and FIG. 6 is an explanatory view of an impingement plate having a spherical convex shape having a spherical convex portion. Figures 7 and 8 show conventional examples. Figure 7 shows a case where the angle of the collision plate is 90" with respect to the acceleration tube, and Figure 8 shows a case where the angle of the collision plate is inclined at 45 degrees with respect to the acceleration tube. It is an explanatory diagram of things. 1... Powder raw material input port 5... Outlet port 2...
・Compressed air supply nozzle 6...Crushing chamber wall 3...Acceleration tube 7...Raw material powder 4...Collision plate

Claims (3)

[Claims] (1) Collision type consisting of an acceleration tube that conveys and accelerates powder using high-pressure gas, and a collision plate that crushes the powder ejected from the acceleration tube by impact force in the crushing chamber opposite the acceleration tube outlet. In the air flow pulverizer, the collision plate has a convex part in the center of the collision plate surface that disperses the powder flying in the other direction along with the high-pressure air from the acceleration tube, and the edge part of the collision plate has a convex part that disperses the powder flying in the other direction. An impingement type air flow crusher characterized by having a guide portion that efficiently causes secondary collision with the wall of a crushing chamber by regulating the flow direction of the powder without significantly reducing kinetic energy. (2) The collision type air flow crusher according to claim 1, wherein the convex portion at the center of the collision plate has a curved surface or a similar shape. (3) The angle θ of the guide part on the edge of the collision plate is 95° or more1
The impingement type air flow crusher according to claim 1, characterized in that the angle is less than 35 degrees, and the impingement type air flow crusher has a concave curved surface or a similar shape.