JPH02111459A - Colliding type gas stream pulverizer - Google Patents

Abstract

PURPOSE:To improve fine pulverized treating capacity by forming expansion angle of an accelerating tube to >=7 deg. and <=9 deg. to reduce pressure loss in the accelerating tube. CONSTITUTION:The expansion angle theta of the accelerating tube 2 connecting with a high pressure gas supplying nozzle 3 is formed to >=7 deg. and <=9 deg.. In this range, mixed gas stream of the high pressure gas supplied from the high pres sure gas supplying nozzle 3 with particles of the pulverizing material supplied from a pulverizing material supplying hole 1 can be collided against the colliding plate 6 while reducing the pressure loss in the accelerating tube 2 to the min. limit. Therefore, the fine pulverized treating capacity can be improved. Further, by forming the apex angle psi of the colliding plate 6 to >=110 deg. and <180 deg., the pulverizing material is dispersed to the whole circumferential direction, and by developing secondary collision with a pulverizing chamber wall, further fine pulverized treating capacity can be improved.

Description

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

[Prior art] A collision-type air flow crusher using a jet stream places the material to be crushed on the jet stream to form a particle mixed air stream, injects it from the outlet of an accelerating tube, and places this particle mixed air stream in front of the outlet of the accelerating tube. The material to be crushed is to be crushed by the impact force by colliding with a collision plate. The details will be explained below based on FIG. 3.

Outlet 1 of the acceleration tube 12 connected to the high pressure gas supply nozzle 13
A collision plate 16 is provided opposite to the acceleration tube 12, and by the flow of the high-pressure gas supplied to the acceleration tube 12, the material to be crushed is introduced into the inside of the acceleration tube 12 from the material supply port 11 communicated with the middle of the acceleration tube 12. The collision plate 1 is sucked in and injected together with high pressure gas.
6, and the impact causes it to shatter. When the raw material to be crushed is used to crush the raw material to a desired particle size, a classifier is arranged between the raw material supply port 11 and the discharge port to form a closed circuit, and the raw material to be crushed is supplied to the classifier. and supplying the coarse powder from the to-be-pulverized material supply port 11,
After pulverization, the pulverized material is returned to the classifier through the discharge port 17 to be classified again, and the fine powder is
A finely ground product with the desired particle size is obtained.

[Problems to be Solved by the Invention] However, in the conventional example described above, the divergence angle θ of the acceleration tube is 6.5 degrees or less, which is narrow, so when the flow rate of high-pressure gas is increased, a pressure loss occurs within the acceleration tube. There was a drawback that the desired improvement in pulverization processing capacity could not be achieved.

[Means and operations for solving the problems] An object of the present invention is to solve the above-mentioned problems and provide a pulverizer that grinds efficiently.

That is, the present invention has an acceleration tube that conveys and accelerates the material to be crushed by high-pressure gas, and directs a mixed air flow of the high-pressure gas and particles of the material to be crushed, which is injected from the outlet of the acceleration tube, to the outlet of the acceleration tube. In the collision-type air flow crusher, which crushes the particles by colliding with a collision plate provided at
By setting the apex angle to 9 degrees or more, pressure loss in the acceleration tube is reduced without reducing the speed of airflow, and the apex angle is 1
By providing a conical collision plate with an angle of 10 degrees or more but less than 180 degrees, the material to be crushed that collides with the collision plate is dispersed in the entire circumferential direction and is pulverized by secondary collision with the opposing crushing chamber wall. This makes it possible to provide an impingement type air flow crusher that improves throughput.

Hereinafter, the present invention will be explained based on examples.

[Example] Fig. 1 and Fig. 2 are schematic diagrams showing an embodiment of the present invention, Fig. 2 is an enlarged view of the main part of Fig. 1, and the acceleration tube 2 is shown in Fig. 3. Like the conventional collision type air flow crusher, a high pressure gas supply nozzle 3 is connected, and a collision plate 6 is provided opposite the outlet 4 of the acceleration tube 2. The acceleration tube 2 has a spreading angle θ
is a monotonically expanding tube where the angle is greater than or equal to 7 degrees and less than or equal to 9 degrees. Furthermore, if the spreading angle θ is set in the range of 7.5 degrees or more and 8.5 degrees or less, the pulverization processing capacity can be improved and is optimal.The operation of the above embodiment will be explained below. In order to improve the pulverization processing capacity of an impingement-type airflow pulverizer, it is effective to increase the flow rate of high-pressure gas that provides the impact force for pulverization. If the acceleration tube is less than 7 degrees, pressure loss will occur inside the acceleration tube.
If it is not possible to improve the pulverization capacity to the desired capacity (according to the increase in high-pressure gas flow rate), but on the other hand, in the case of an accelerator tube with a spreading angle θ exceeding 9 degrees, as the angle of the accelerating tube widens, the The cross-sectional area of outlet 4 becomes larger, and conversely,
Since the speed of the particle mixture air flow injected from the accelerator tube decreases, it cannot be used to improve the pulverization ability. Accelerator tubes are the most suitable for improving the pulverization capacity.

A toner material consisting of a mixture of the above formulation is heated and kneaded, and after cooling and solidifying, a hammer mill is used to give a powder of 100-1000
The material to be crushed is coarsely ground into μm particles, d l = 11 mm, d , = 29 mm.
, L: 133mm f/Cm to 6.0 in a crusher having an acceleration tube of θ=7.7 degrees and a conical collision plate of ψ++160 degrees.
When the toner material was pulverized to a volume average diameter of 12 μm by supplying pressurized air of No. 2, the processing capacity was 1.8 times that of the conventional example (Comparative Example 1).

111U The toner material to be crushed used in Example 1 was d+, 11
mm, dz; 29 mm, L = 133 mm, volume averaged with a pulverizer having an acceleration tube with a θ depth of 7.7 degrees and a conventional flat collision plate (hereinafter referred to as a vertical plane collision plate) orthogonal to the acceleration tube. When finely pulverized to a diameter of 12 μm, the processing capacity was 1.5 times that of the conventional example.

Proportion 1' to l The raw material for toner to be ground used in Example 1 was pulverized to a volume average diameter of 12 μm using a conventional pulverizer. The configuration of the conventional pulverizer described here is as follows.

d I z 9mm, d s =
24mm, L = 153mm.

θ = 5.6 degrees acceleration tube and vertical plane collision plate.

[The raw material of the toner to be crushed used in Example 1, d + = 1
1mm, da =24mII1. L 1113
3mm.

θ: When pulverized to a volume average diameter of 12 μm using a pulverizer with an acceleration tube of 5.6 degrees and a vertical plane collision plate, the diameter was 12 μm compared to the conventional example.
The processing capacity was twice as large.

The raw material of the toner to be crushed used in Example 1 is d + =
11mm, da = 29mm, L = 17
2mm.

θ: When pulverized to a volume average diameter of 12 μm using a pulverizer with an accelerating tube of 6.0 degrees and a vertical plane collision plate, the particle diameter was 12 μm compared to the conventional example.
．． The processing capacity was three times greater.

A summary of each side above is as follows.

*- Comparative Example 1 is used as the standard (1,0).

In Comparative Example 2.3, the high pressure gas supply nozzle diameter d.

11mm from 9IIlffl of Comparative Example 1, which is a conventional product.
Even though the flow rate of high-pressure air for pulverization was increased by about 1.5 times, the pulverization capacity was only 1.
．． It only improved by less than 3 times. On the other hand, in Examples 1 and 2, it was possible to improve the pulverization capacity by an amount equal to or greater than the rate of increase in the high-pressure air flow rate.

[Effect of the invention] As explained above, when the divergence angle θ of the accelerator tube is set to 7 degrees or more, 9
The apex angle of the collision plate should be less than 110 degrees.
By making the conical shape less than 0 degrees, it is possible to increase the pulverization throughput without making the device thicker.

[Brief explanation of drawings]

1 and 2 are cross-sectional views of a pulverizer embodying the present invention, and FIG. 2 is an enlarged view showing the main parts of FIG. 1. Third
The figure is a schematic diagram showing a conventional example. 1.11 - Material to be crushed supply port 2.12 - Acceleration tube 3.13 - High pressure gas supply nozzle 4.14 - Acceleration tube outlet 5.15 - Grinding chamber 6.16 - Collision plate 7.17 - Discharge port

Claims (2)

[Claims] (1) It has an acceleration tube that conveys and accelerates the material to be crushed by high-pressure gas, and a mixed air flow of the high-pressure gas and particles of the material to be crushed is injected from the outlet of the acceleration tube, and is provided opposite to the outlet of the acceleration tube. A collision type air current pulverizer configured to cause pulverization by colliding with a collision plate, characterized in that the expansion angle θ of the acceleration tube is 7 degrees or more and 9 degrees or less. (2) The collision type air flow crusher according to claim 1, wherein the collision plate has a conical shape with an apex angle of 110 degrees or more and less than 180 degrees.