JPH0780414A - Air separator - Google Patents

Abstract

PURPOSE:To provide a separator capable of improving classification accuracy significantly in comparison with a conventional air separator and adjusting the classification point of coarse powder. CONSTITUTION:This air separator consists of a hopper-type main system casing 16 with a rotatable classification blade 20 formed at the upper part of the interior and a fine powder transport duct 22 connected to the upper side and a hopper-type eddy chamber 25 with a classified gas induction orifice 23 which introduces a classified gas 6 from a tangential direction formed at the lower part of the main system casing 16 and a coarse powder cut nozzle 24 at the lower end part. In addition, at the axial center position of a small diameter part, a dispersion cone 26 with a conical top and an inverted conical bottom is arranged elevatably, and a raw material chute 27 for throwing a raw material powder 10 is formed right above the dispersion cone 26. It is possible to properly increase and decrease the flow path cross-sectional area of an annular flow path 31 and thereby freely adjust the flow velocity of an ascending swirl by allowing the dispersion cone 26 to ascend and descend.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air separator.

[0002]

2. Description of the Related Art FIG. 2 shows an example of a conventional air separator, where 1 is a separator body, 2 is an air fan, 3 is a vane, 4 is a classification blade, and 5 is a cyclone.
A classifying gas 6 from the air fan 2 is guided to the inside from the side of the lower casing 7 of the separator body 1, and is passed between a plurality of vanes 3 arranged in a cylindrical shape with a predetermined angle, whereby a rising swirl flow is generated. And

On the other hand, the raw material powder 10 charged from the powder supply pipe 9 connected from the upper center of the upper casing 8 is once dropped on the dispersion plate 12 rotated by the drive shaft 11 and dispersed by the centrifugal force. Drop it further.

The raw material powder 10 dropped in this way is
Riding on the upward swirling flow of the classification gas 6, the coarse powder 10a having a relatively large particle size in the raw material powder 10 is naturally dispersed on the outer peripheral side by the action of the centrifugal force and is taken out from the lower end of the lower casing 7, and has a relatively small particle size. The fine powder 10b having a small size is swung upward and conveyed.

The fine powder 1 which is conveyed upward by the classification gas 6
0b is obtained by passing a plurality of classification blades 4 radially attached to the outer peripheral portion of a mounting plate 13 which rotates integrally with the dispersion plate 12 at required intervals during the rotation thereof as indicated by an arrow A in the figure. Further classification and guided to the center side, the classification gas 6
Along with the fine powder discharge duct 14 connected to the top of the upper casing 8, the cyclone 5 is swept into the cyclone 5 from the tangential direction, and is separated from the classification gas 6 by the centrifugal force of the swirl flow. Taken out,
The classified gas 6 is returned to the air fan 2 through the air supply pipe 15 inserted in the center of the upper portion of the cyclone 5 and circulated.

As described above, the raw material powder 10 charged into the separator body 1 is separated into the coarse powder 10a and the fine powder 10b and collected respectively.

[0007]

However, in the air separator having the above-mentioned conventional structure, the dispersion plate 12 for dropping the raw material powder 10 is provided close to the classification blade 4,
The raw material powder 10 is classified by the classifying blade 4 as soon as it rides on the rising swirl flow of the classification gas 6, the raw material powder 10 is not guided to the classifying blade 4 in a sufficiently dispersed state, and the raw material powder 10 is centrifuged to the raw material powder 10. The refined powder 10b recovered because the opportunity for natural separation due to the action of force is not sufficiently stable.
The ratio of the coarse powder 10a mixed therein is high, and further, the coarse powder 10a which is separated to the outer peripheral side by the action of centrifugal force and the classification blade 4 and falls, is directly recovered without being given another classification opportunity. A highly accurate raw material powder 1 having a high ratio of the refined powder 10b mixed in the recovered coarse powder 10a.
There was a problem that classification of 0 could not be performed.

Further, in the conventional air separator,
There is no means for adjusting the classification point of the coarse powder 10a, and the classification blade 4
There was also a problem that only the classification point of the refined powder 10b could be adjusted by changing the number of revolutions.

The present invention has been made in view of the above circumstances, and can significantly improve the classification accuracy as compared with the conventional air separator, and further, the classification point of the coarse powder can be arbitrarily adjusted. Is intended to provide.

[0010]

DISCLOSURE OF THE INVENTION The present invention comprises a hopper-shaped main casing having a rotatable classification blade at an upper position inside and a refined powder discharge duct connected to the upper side of the classification blade, and the main casing lower part. At the lower end of the small diameter part of, a hopper-shaped swirl chamber having a classification gas inlet for introducing the classification gas from the tangential direction and having a coarse powder cutting nozzle at the lower end is connected, and the small diameter part below the main casing is A dispersion cone having a conical upper part and an inverted conical lower part is arranged at an axial position so as to be able to move up and down, and a raw material chute for introducing raw material powder is provided directly above the dispersion cone. It relates to an air separator.

[0011]

Therefore, according to the present invention, the classification gas introduced from the classification gas introduction port rises as a swirling flow in the swirl chamber and rises once in the annular flow passage around the dispersion cone, and then in the main casing. Is further swirled up, passes through the rotating classification blade, and flows into the refined powder discharge duct.

On the other hand, the raw material powder introduced by the raw material chute directly above the dispersing cone is dispersed substantially evenly in the peripheral annular flow passage due to the conical shape of the upper portion of the dispersing cone, and falls to the annular flow passage around the dispersing cone. The coarse powder with relatively large particle size in the raw material powder is naturally separated to the outer peripheral side by the action of the centrifugal force and is naturally separated on the outer peripheral side, and further separated here. The raw material powder that was not present is further classified by passing through the classifying blade that swirls up and rotates, and only the refined powder is guided to the refined powder discharge duct.

Further, the coarse powder separated to the outer peripheral side by the action of the centrifugal force and the coarse powder repelled by the classification blade are
Although it falls along the inner wall of the main body casing, since a rising swirl flow with a high flow rate is generated in the annular flow path around the dispersion cone, coarse powder with a particle size close to that of refined powder re-enters this rising swirl flow, and Repeatedly given similar classification opportunities.

Further, the coarse powder having a relatively large particle size cannot fall on the upward swirling flow and falls into the swirl chamber as it is, and is cut out from the coarse powder cutting nozzle through the rotary valve.

Here, when the dispersion cone is moved up or down, the distance between the inverted cone shape at the lower part of the dispersion cone and the small diameter part at the lower part of the main body casing is increased or decreased, and the flow path of the annular flow path formed around the dispersion cone is increased or decreased. Since the cross-sectional area is increased / decreased, it is possible to arbitrarily adjust the flow velocity of the upward swirling flow generated in the annular flow path, and it is possible to adjust the classification point of the coarse powder to be recovered by the coarse powder cutting nozzle. .

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, in which the same reference numerals as those in FIG. 2 represent the same parts.

Reference numeral 16 in the drawing denotes a hopper-shaped main body casing, and a rotary plate 19 is provided at an upper position inside the main body casing 16 by a drive shaft 18 connected to a drive motor 17 outside the main body casing 16 so as to transmit torque. It is rotatably supported, and a large number of classification blades 20 are radially attached to the outer periphery of the upper surface of the rotary plate 19.

Further, on the top of the main body casing 16 above the classification blade 20, there is formed a throttle projection 21 for guiding only the classification gas 6 passing between the classification blades 20. A fine powder discharge duct 22 is connected to the convex portion 21.

Further, at the lower end of the small-diameter portion 16a below the main body casing 16, there is provided a classification gas inlet 23 through which the classification gas 6 can be introduced in a tangential direction, and a hopper shape having a coarse powder cutting nozzle 24 at the lower end. The swirl chamber 25 is provided.

Further, at the axial center position of the small diameter portion 16a below the main body casing 16, a dispersion cone 26 having an upper cone shape and a lower cone shape is arranged so as to be movable up and down. A raw material chute 27 for introducing the raw material powder 10 is inserted and installed in the main body casing 16 just above 26.

Here, the dispersion cone 26 is supported by a plurality of support bars 29 inserted from the outside through through slits 28 formed in the body casing 16, and each support bar 29 is outside the body casing 16. It is supported by a lifting device 30 such as a hydraulic cylinder that stands upright on the upper surface of the spiral chamber 25 and is vertically expandable and contractible.

In the figure, 31 is an annular channel formed around the dispersion cone 26, 32 is a dustproof bellows for sealing between the support bar 29 and the through slit 28, and 33 is a coarse powder cutting nozzle 24. A rotary valve provided, 34 is a rotary valve provided in the raw material chute 27.

Then, while rotating the classification blade 20,
When the classification gas 6 is introduced into the swirl chamber 25 through the classification gas inlet 23, the classification gas 6 rises as a swirling flow in the swirl chamber 25, and the flow velocity is once increased in the annular flow passage 31 around the dispersion cone 26. After being raised, it further swirls up in the body casing 16, passes through the rotating classification blade 20, and flows into the fine powder discharge duct 22.

In this state, when the raw material powder 10 is charged from the raw material chute 27 directly above the dispersion cone 26, the raw material powder 1
0 falls substantially evenly in the surrounding annular flow channel 31 due to the conical shape of the upper part of the dispersion cone 26 and falls, but as described above, the classification gas 6 having the increased flow velocity flows in the annular flow channel 31.
Since the upward swirling flow of the
Is blown up by this upward swirling flow and is swirling up and sufficiently dispersed.

At this time, the raw material powder 1 is produced by the action of centrifugal force.
The coarse powder 10a in 0 is naturally separated on the outer peripheral side, and the fine powder 1
0b is swung upward as it is and reaches the classification blade 20.

In the classifying blade 20, the coarse powder 10a, which cannot be completely separated by the natural separation due to the centrifugal force and is mixed and conveyed in the fine powder 10b, is repelled while passing through the rotating classifying blade 20 and classified. Only the fine powder 10b that can pass through the blades 20 is classified, guided to the fine powder discharge duct 22, and collected by a cyclone (not shown) or the like.

On the other hand, the coarse powder 10a separated to the outer peripheral side by the action of the centrifugal force and the coarse powder 10a repelled by the classifying blade 20 fall along the inner side wall of the main body casing 16, but around the dispersion cone 26. Since the upward swirling flow having a high flow velocity is generated in the annular flow path 31 of No. 3, the coarse powder 10a having a particle size close to that of the refined powder 10b rides on the rising swirl flow again, and the classification opportunity similar to the above is repeatedly given.

Further, the coarse powder 10a having a relatively large particle size cannot fall on the upward swirling flow and falls into the spiral chamber 25 as it is, and is cut out from the coarse powder cutting nozzle 24 through the rotary valve 33.

Here, the dispersion cone 26 is moved up and down by the lifting device 3
When it is lifted or lowered by 0, it has an inverted conical shape under the dispersion cone 26 and a small diameter portion 16a under the main body casing 16.
Since the interval w between and is increased or decreased and the flow passage cross-sectional area of the annular flow passage 31 formed around the dispersion cone 26 is increased or decreased, the flow velocity of the upward swirling flow generated in the annular flow passage 31 can be arbitrarily adjusted. This makes it possible to adjust the classification point of the coarse powder 10a to be collected by the coarse powder cutting nozzle 24.

The flow velocity of the upward swirling flow generated in the annular flow passage 31 may be adjusted depending on the properties of the raw material powder 10 charged from the raw material chute 27 for the purpose of improving the dispersibility thereof.

Therefore, according to the above-mentioned embodiment, the raw material powder 10 can be sufficiently dispersed, and the raw material powder 10 can be sufficiently and stably given the opportunity of natural separation by the action of the centrifugal force. The coarse powder 10a having a large particle size can be surely provided by repeatedly providing the classification blade 20 with a classification opportunity.
Since only the coarse powder cutting nozzle 24 can be dropped, the classification accuracy can be greatly improved as compared with the conventional air separator.

Further, by raising and lowering the dispersion cone 26, the flow passage cross-sectional area of the annular flow passage 31 formed around the dispersion cone 26 can be increased or decreased.
Since the flow velocity of the upward swirling flow generated in the surroundings can be arbitrarily adjusted, the classification point of the coarse powder 10a to be collected by the coarse powder cutting nozzle 24 can be adjusted very easily.

The air separator according to the present invention is not limited to the above-mentioned embodiment, but a device other than a hydraulic cylinder may be used for the lifting device, and other than that, the range does not depart from the gist of the present invention. Of course, various changes can be made within.

[0035]

According to the air separator of the present invention described above, various excellent effects as described below can be obtained.

(I) The raw material powder can be made into a sufficiently dispersed state, and the raw material powder can be sufficiently and stably given the opportunity of natural separation by the action of centrifugal force.
Further, since the classification blades can repeatedly give the classification opportunity to reliably drop only the coarse powder having a large particle size to the coarse powder cutting nozzle, the classification accuracy can be greatly improved as compared with the conventional air separator.

(II) By raising and lowering the dispersion cone, the cross-sectional area of the annular flow passage formed around the dispersion cone can be increased or decreased, and the flow velocity of the rising swirl flow generated around the dispersion cone can be arbitrarily set. Can be adjusted,
The classification point of the coarse powder to be collected by the coarse powder cutting nozzle can be adjusted very easily.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing a conventional example.

[Explanation of symbols]

 6 Classification gas 10 Raw material powder 16 Main body casing 16a Small diameter part 20 Classification blade 22 Fine powder discharge duct 23 Classifying gas introduction port 24 Coarse powder cutting nozzle 25 Whirlpool chamber 26 Dispersion cone 27 Raw material chute

Claims (1)

[Claims] 1. A hopper-shaped main body casing having a rotatable classification blade at an upper position inside and a refined powder discharge duct connected to an upper side of the classification blade, and a classification gas is provided at a lower end of a small diameter portion below the main body casing. Is connected to a hopper-shaped spiral chamber having a classification gas introduction port capable of introducing tangentially and having a coarse powder cutting nozzle at the lower end, and the upper part is conical at the axial center position of the small diameter part below the main body casing. Distributing cone, whose lower part is shaped like an inverted cone, is arranged so that it can move up and down.
An air separator comprising a raw material chute for introducing raw material powder directly above the dispersion cone.