JPS6193880A - Sorter - 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 [Field of Industrial Application] The present invention relates to a classifier that separates powder into fine powder and coarse powder.

[Conventional technology]

As a conventional technology for a classifier that centrifugally separates powder into fine powder and coarse powder, as shown in FIG. A powder supply cylinder 23 is provided above the classification chamber 22, and the powder is supplied from the supply cylinder 23 into the classification chamber 22, and the powder is rotated at high speed in the classification chamber 22 and centrifuged into fine powder and coarse powder. death,
The fine powder moving toward the center of the classification chamber 22 is suctioned and discharged from the fine powder discharge pipe 24 connected to the center of the classification plate 21.
There is one in which the coarse powder swirling around the outer periphery of the classification chamber 23 is discharged from an annular coarse powder discharge hole 25 provided at the outer periphery of the classification plate 21.

[Problem that the invention seeks to solve]

In the classifier described above, in order to improve the classification efficiency, it is necessary to disperse and supply powder to the classification chamber.

However, in the above classifier, the powder is supplied from the supply port 26 provided at the upper part of the powder supply cylinder 23, and the powder is descended while swirling around the outer circumference of the supply cylinder 23 to the classification chamber 22.
Since it is configured to supply 23°, -0, 5.9. -One.

Powder often aggregates due to electrification caused by contact, becomes a lump, and flows into the classification chamber 22, which poses a problem in classification efficiency.

In addition, when making fine powder into a product, the yield is poor, and moreover, the suction force acting on the fine powder discharge pipe 24 causes the classification chamber 22 to
Since the powder is accelerated in the swirling direction by sucking secondary air between the loopers 27 arranged in an annular manner on the outer periphery of the particle, the velocity in the swirling direction acting on the particles is small, and the classification point is placed in the ultra-fine powder region. It was not possible to set the settings, and there was a problem with classification accuracy.

For this reason, the field of new ceramics, which requires classification on the order of submicrons, and the field of powders, such as electronic toner, which requires ultra-precision classification, have the disadvantage of not being able to use the classifier described above. there were.

Therefore, the technical object of the present invention is to solve the above-mentioned disadvantages, improve the classification efficiency, and make it possible to set the classification point in the ultra-fine powder region.

[Means for solving problems]

In order to solve the above problems, the first invention provides a nozzle that injects high-pressure gas in the tangential direction of the outer periphery of the classification chamber,
The structure is such that the lower outlet of the powder powder (located on the nozzle) is communicated with the gas flow path of the nozzle, and the second invention has another high-pressure gas injection nozzle in addition to the above-mentioned nozzle. The gas flow passage of this injection nozzle and the exhaust gas outlet provided at the top of the classification chamber are connected through a circulation passage, and a solid-gas separator such as a cyclone is connected to the circulation passage, and the gas exhaust of this solid-gas separator is connected to the circulation passage. The structure is such that a flow rate regulating pulp is provided at the outlet.

[For production]

The classifier configured as described above injects high-pressure gas into the classification chamber from the nozzle, and uses the suction effect of the injection to introduce the powder in the powder hopper into the gas flow path of the nozzle, supplying the powder to the classification chamber. The powder is centrifuged into fine powder and coarse powder by rotating at high speed in a classification chamber.

Through the supply of powder as described above, the powder sucked into the gas flow path of the nozzle collides with the high-pressure gas, so that the powder can be distributed and supplied to the classification chamber.

Further, in the second invention, the gas in the classification chamber is introduced into the solid-gas separator from the exhaust gas outlet, and is separated into gas and powder in the separator. is re-supplied into the classification chamber by the suction action of In this way, by removing the gas in the classification chamber, the speed of the powder rotating in the classification chamber towards the center can be reduced, the classification point can be made smaller, and the powder can be recycled back into the classification chamber. According to
Yield can be increased.

〔Example〕

As shown in FIG. 1, the lower part of the casing 1 is tapered, and the opening at the lower end is a coarse powder collection hole 2. Further, an umbrella-shaped classification plate 3 is provided at the inner upper part of the casing 1, and a cylindrical classification chamber 4 is formed above the classification plate 3.

A fine powder discharge pipe 5 is connected to the central portion of the classification plate 3, and an end portion of the fine powder discharge pipe 5 penetrates the side portion of the casing 1 and projects outward. Furthermore, an annular coarse powder discharge hole 6 is provided on the outer periphery of the classification plate 3.

On the outer periphery of the classification chamber 4 (as shown in FIG. 2, a large number of loopers 7 are arranged in an annular manner, and between the loopers 7,
An injection nozzle 8 is arranged to inject high-pressure gas toward the outside of the classification chamber 4 in a tangential direction. The number of injection nozzles 8 is arbitrary, and in order to eliminate uneven swirling of the powder supplied into the classification chamber 4, it is preferable to provide a plurality of injection nozzles 8 at equal angles.

As shown in FIG. 3, a powder hopper 9 is disposed above the injection nozzle 8, and a lower outlet of the powder hopper 9 communicates with the gas flow passage 8' of the injection nozzle 8 to By circulating high pressure gas through the flow path 8', the powder in the powder hopper 9 is sucked into the gas flow path 8'.

Now, when high pressure gas is supplied into the classification chamber 4 from each injection nozzle 8, the powder in the powder hopper 9 is moved into the gas flow path 8' by the suction force of the high pressure gas flowing through the gas flow path 8' of the injection nozzle 8. will be introduced in At this time, the powder is transferred to the gas flow path 8
Because it collides with the high pressure gas flowing through ', it is sufficiently dispersed and flows into the classification chamber 4 in a dispersed state.

On the other hand, the fine powder discharge pipe 5 is suctioned by a proa (not shown), and the inside of the classification chamber 4 is made to have a negative pressure by the suction. Therefore, secondary air is introduced into the classification chamber 7 from between the loopers 7, and a strong and rectified swirl flow is generated in the classification chamber 4 by the introduction of the secondary air and the injection of high-pressure gas from the nozzle 8. is generated. Therefore, the powder supplied into the classification chamber 4 is rotated at high speed in the classification chamber 4 and centrifugally separated into fine powder and coarse powder, and the fine powder that moves to the center of the classification chamber 4 is transferred to the fine powder discharge pipe. On the other hand, the coarse powder swirling around the outer periphery of the classification chamber 4 flows to the lower part of the casing 1 from the coarse powder discharge hole 6 and is discharged from the coarse powder recovery hole 2.

As shown in FIG. 1, a fan 11 that is rotationally driven by a motor 10 is provided at the upper part of the inside of the classification chamber 4, and by rotating the fan 11 at high speed during the classification of powder, the inside of the classification chamber 4 is Since the swirling speed of the swirling particles can be further increased, the classification point can be further reduced.

FIG. 4 shows another embodiment of the classifier, in which an umbrella-shaped guide plate 12 is provided at the upper part of the classification chamber 4, and a gas discharge path 13 is formed between the guide plate 12 and the top wall of the classification chamber 4. An exhaust gas outlet 14 is provided at the upper part of the gas exhaust passage 13 so that the gas inside the classification chamber 4 is discharged from the exhaust gas outlet 14. Further, in order to prevent powder from adhering to the exhaust gas outlet 14, a socket 19 for introducing the pipe 7 is provided.

With such a configuration, it is possible to reduce the velocity of particles rotating in the classification chamber 4 toward the center, and the classification point can be further reduced.

Further, the exhaust gas outlet 14 and the gas flow passage 8' of the one injection nozzle 8 are communicated through a circulation passage 15, and a solid-gas separator 16 such as a cyclone is connected to the circulation passage 15.
A flow control valve 18 is provided in the gas discharge path 17 of the solid-gas separator 16.

With the above configuration, the gas flowing out from the exhaust gas outlet 14 flows to the solid-gas separator 16, and the solid fraction 14 is separated into gas and powder by the device 16, and the powder is passed through the gas flow path 8 of the nozzle 8. Since the high-pressure gas flowing through ' is supplied into the classification chamber 4 again by the suction action, the yield can be improved. In addition, the amount of gas discharged can be adjusted by operating the regulating pulp 18 provided in the gas discharge path 17 of the solid-gas separator 16.
The speed toward the center of the powder swirling within the classification chamber 4 can be adjusted as desired, and the classification point can be changed.

〔effect〕

As described above, the present invention is capable of sucking powder into the gas flow path of the nozzle by the suction action of the high-pressure gas injected into the classification chamber from the nozzle, and supplying the powder together with the high-pressure gas into the classification chamber. Therefore, the powder can be distributed and supplied into the classification chamber, and the classification efficiency can be improved.

Furthermore, since the gas inside the classification chamber is vented from the exhaust gas outlet provided at the top of the classification chamber, the speed of the powder swirling in the classification chamber toward the center can be reduced. Therefore, the classification point of the powder becomes small, and ultrafine powder can be obtained.

Furthermore, the gas flowing out from the exhaust gas outlet is guided to a solid-gas separator to separate it into gas and powder, and the powder is recycled into the classification chamber, improving the yield when turning fine powder into products. In addition, by operating the regulating pulp provided in the gas discharge path of the solid-gas separator, the speed toward the center of the powder swirling in the classification chamber can be adjusted, so the classification point can be adjusted as desired. can do.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing an embodiment of the classification device according to the present invention, Fig. 2 is a cross-sectional plan view of the same, Fig. 3 is a cross-sectional view showing the nozzle mounting part of the above, and Fig. 4 is a cross-sectional view of the same. Another embodiment of the invention is schematically shown, and FIG. 5 is a schematic diagram showing a conventional classifier.

Claims (2)

[Claims] (1) A classification plate is provided inside the upper part of the casing, and powder is supplied into a cylindrical compartment formed above the classification plate,
This powder is rotated at high speed in the classification chamber and centrifuged into fine particles and coarse particles.The fine particles are sucked and discharged from the fine powder discharge pipe connected to the center of the classification plate, and the coarse particles are transferred to the outer periphery of the classification plate. In a classifier configured to discharge coarse powder from a formed coarse powder discharge hole, an injection nozzle for injecting high-pressure gas in a tangential direction to the outside of the classification chamber is provided, and a lower outlet of a powder hopper is disposed above the injection nozzle. A classifier characterized by communicating with a gas flow path of an injection nozzle. (2) A classification plate is provided inside the upper part of the casing, and powder is supplied into a cylindrical classification chamber formed above the classification plate,
This powder is centrifuged into fine particles and coarse particles by rotating it at high speed in the classification chamber, and the fine particles are sucked and discharged from the fine powder discharge pipe connected to the center of the classification plate, and coarse particles are formed on the outer periphery of the classification plate. In the classifier, a plurality of injection nozzles are provided for injecting high-pressure gas in a tangential direction to the outside of the classification chamber, and one of the injection nozzles is left out. A powder hopper is arranged above the other injection nozzle, and the lower outlet of the hopper is communicated with the gas flow passage of the injection nozzle, and the gas flow passage of the remaining injection nozzle and the exhaust gas outlet formed at the top of the classification chamber are connected. communicated through a circulation passage, a solid-gas separator is connected to the circulation passage, and a flow rate regulating valve is provided in the gas discharge passage of the solid-gas separator.