JP3088471B2 - Sieving device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for sieving fine particles having excellent sieving efficiency. More specifically, the present invention relates to a nozzle for blowing air toward the screen of a substantially circular screen, which is provided directly below the screen of the screen. In a sieving apparatus which is rotatably supported in close proximity to a unit, a plurality of units in which the above-mentioned rotary nozzle, its driving unit, and an air introduction pipe to the driving unit are integrally arranged in a cylindrical framework are stacked in a plurality of stages. Then, selectively open the air introduction pipe of each sieving unit to the atmosphere, a sieving device that generates a sieving action by an air flow flowing in the air introduction tube, a cyclone unit in the sieving device, Also, the present invention relates to a sieving apparatus in which particle dispersion units are selectively combined.

[0002] The present invention is used for sieving powders having a wide range of particle size distribution from coarse particles to fine particles in the field of processing various kinds of powders including ceramics, pharmaceuticals, coloring materials, foods, and electronic materials. You.

[0003]

2. Description of the Related Art Conventionally, powder having a particle size distribution is sieved,
In order to obtain particles having a uniform particle size and to remove fine particles and coarse particles, a wire mesh or a sieve mesh made of organic fibers is used. Also, in order to efficiently pass particles finer than the mesh of the sieve mesh, the sieve mesh is shaken, vibration is applied to the sieve mesh, or an impact is given to the sieve mesh by a ball, a hammer, or the like. The method has been adopted.

However, recently, with the diversification and sophistication of needs in the field of powder processing, the necessity of sieving fine particles has rapidly increased. However, for example, in sieving fine particles of 50 microns or less, because the surface activity of the particles is large, aggregation and clogging are likely to occur, the sieving speed is reduced, and particles having a particle size smaller than the sieve mesh Is left on the network.

[0005] As a countermeasure against this, conventionally, a rotary nozzle is provided directly below the sieve mesh, and a jet stream is blown below the sieve mesh by compressed air to remove clogging. A method of sieving by carrying a powder in a dispersed state by carrying the powder in this air flow, or
A method of rotating a cylindrical sieve mesh, fixing an air nozzle with a slit in the vicinity of the cylindrical sieve mesh, and removing clogging by air ejected from the slit is adopted.

[0006]

However, each of the conventional apparatuses has the following two problems. The first problem is that even if a single device can separate particles of a certain particle size or more and particles of a smaller particle size from one device due to the complexity of the mechanism for relatively moving the air nozzle with a slit and the sieve mesh, Fine particles having a uniform particle size within a predetermined particle size range could not be obtained. Therefore, in order to obtain fine particles having a uniform particle size having a target particle size range, two or more sieving devices provided with sieve nets having different meshes are used in series, or
It was necessary to adopt an inefficient method of replacing a sieve mesh having a different mesh with one sieve and sieving it twice or more.

[0007] The second problem is that the sieving efficiency of the fine particles is not sufficient. That is, in general, in order to sieve fine particles efficiently, the particles are constantly kept in a dispersed state so as not to cause clogging of the sieve mesh, and the particles are allowed to pass through the sieve mesh with the airflow in a dispersed state. Is considered to be effective.

As a result of various studies, the inventors have found that for fine powder sieving, 1 to 5 liters / min.cm
The ^second slit air, be sprayed on the sieve screen in the early period of 2 to 30 cycles was found that it is extremely effective.

However, in the above-described conventional methods and apparatuses, the relative speed between the sieve surface and the slit air nozzle is low due to mechanical limitations, and the particles must be maintained in a dispersed state, and the particles must be supported in the air stream. Difficult to get
There is a disadvantage that the sieving efficiency of fine particles having a relatively large specific gravity of 50 microns or less is not sufficient.

This will be described more specifically below. In the method using the rotary nozzle (for example, ALPINE air jet sieve, Kikkoman fine shifter, Dalton air brush shifter, etc.), since the rotary nozzle is driven by an electric motor provided outside the system, a multi-stage sieve is used. It is difficult to blow a jet stream onto two or more screens of the apparatus, and it is impossible to sieve into particles having three or more particle size ranges. In addition, in the device described in Japanese Utility Model Publication No. 59-39493, the rotation of the rotary nozzle at 60 to 80 RPM is restricted due to the restriction of the cooperation between the suction mechanism of the jet stream to the rotary nozzle and the drive mechanism of the rotary nozzle. It is said that 2 to 3 kg / cm ² of compressed air is required to achieve this.
It is extremely difficult to achieve the condition of high sieving efficiency of blowing air of 5 to 5 liters / min · cm ² onto the sieve at an early cycle of 2 to 30 cycles. There is a problem that the number increases.

Japanese Patent Application Laid-Open No. 57-153775 discloses a method in which an air purge pipe is provided facing a rotatable cylindrical classification screen and opened to prevent clogging of the classification screen with purge air. Are listed. In this apparatus, a cylindrical classification screen is driven by a motor provided outside the system. However, in order to obtain fine particles having a predetermined particle size width and a uniform particle size, a secondary classification screen having a different mesh is used. There was an inconvenience that the two devices had to be operated in series.

That is, in the method of driving a rotary nozzle or a rotary cylinder by a conventional apparatus, it has not been easy to efficiently collect fine particles having a certain particle size and having a uniform particle size.

[0013]

As a means for solving the above problems, the present invention provides: (1) a nozzle which blows air toward a net surface of a substantially circular sieve mesh, is rotated in close proximity to directly below the sieve mesh surface; In a freely sieving apparatus, a sieve mesh (3), a rotary nozzle (4), a drive unit (5) for supporting and driving the rotary nozzle, and an air introducing pipe (6) to the drive unit are cylindrical. The sieving unit (1) is constructed by incorporating the sieving unit (1) into the frame (2), and a plurality of the sieving units (1) are stacked. 6. A sieving apparatus, wherein 6) is independently opened to the atmosphere.

(2) In a sieving apparatus in which a nozzle for blowing air toward a substantially circular screen of a sieve mesh is rotatably provided immediately below the screen of the sieve, a screen (3) includes: A rotary nozzle (4), a drive unit (5) for supporting and driving the rotary nozzle, and an air introduction pipe (6) to the drive unit are assembled in a cylindrical frame (2), and a sieving unit ( 1), a plurality of the sieving units (1) are laminated, and the air introduction pipes (6) of the plurality of sieving units (1) are independently opened to the atmosphere. A partition (1) having a cylindrical frame (9) and a nozzle (10) for generating a swirling air flow in the frame is vertically provided below the lower sieving unit (1).
1) and a cyclone unit (8) consisting of an exhaust pipe (12) which stands upright from the bottom to the center of the frame and communicates with a blower opened near the lower part of the partition (11). A sieving apparatus.

(3) In a sieving apparatus in which a nozzle for blowing air toward a substantially circular screen of a sieve mesh is rotatably provided immediately below the screen of the sieve, the nozzle is provided with a screen (3); A rotary nozzle (4), a drive unit (5) for supporting and driving the rotary nozzle, and an air introduction pipe (6) to the drive unit are assembled in a cylindrical frame (2), and a sieving unit ( 1), a plurality of the sieving units (1) are laminated, and the air introduction pipes (6) of the plurality of sieving units (1) are independently opened to the atmosphere. Above the upper sieving unit (1), a motor (16) and a vacuum suction device (1)
7), a particle dispersion unit (15) comprising a suction pipe (18) connected to the suction section of the reduced-pressure suction device (17) and a discharge pipe (19) extending from the discharge section is installed. ) And the discharge pipe (19) are opened near the upper part of the screen (3) of the uppermost screen unit (1).

(4) In a sieving apparatus in which a nozzle for blowing air toward a net surface of a substantially circular sieve net is rotatably provided immediately below the sieve net surface, the sieve net (3) includes: A rotary nozzle (4), a drive unit (5) for supporting and driving the rotary nozzle, and an air introduction pipe (6) to the drive unit are assembled in a cylindrical frame (2), and a sieving unit ( 1), a plurality of the sieving units (1) are stacked, and the air introduction pipes (6) of the plurality of sieving units (1) are independently opened to the atmosphere. A cylindrical frame (9) and a partition wall (1) for vertically suspending a nozzle (10) for generating a swirling air flow in the frame below the lower sieving unit (1).
1) and a cyclone unit (8) composed of an exhaust pipe (12) which is erected from the bottom to the center of the frame and communicates with a blower opened near the lower part of the partition (11). Above the uppermost sieving unit (1), a vacuum suction device (17), a suction pipe (18) connected to a suction section of the vacuum suction apparatus (17), and a discharge pipe (19) extending from a discharge section. And the suction pipe (18) and the discharge pipe (19) are opened near the upper part of the screen (3) of the uppermost screening unit. Sieving device.

(5) In a sieving apparatus in which a nozzle for blowing air toward a substantially circular screen of a sieve mesh is rotatably provided immediately below the screen of the sieve, a sieve screen (3); A rotary nozzle (4), a drive unit (5) for supporting and driving the rotary nozzle, and an air introduction pipe (6) to the drive unit are assembled in a cylindrical frame (2), and a sieving unit ( 1) and a cylindrical frame (9) below the sieving unit (1);
A partition wall (11) having a nozzle (10) for generating a swirling flow in the frame body, and an exhaust pipe communicating with a blower which stands upright from the bottom to the center of the frame body and opens near the lower part of the partition wall ( 12. A sieving apparatus, wherein a cyclone unit (8) comprising:

(6) In a sieving apparatus in which a nozzle for blowing air toward a substantially circular screen of a sieve mesh is rotatably provided immediately below the screen of the sieve, and is rotatably provided, a sieve screen (3); A rotary nozzle (4), a drive unit (5) for supporting and driving the rotary nozzle, and an air introduction pipe (6) to the drive unit are assembled in a cylindrical frame (2), and a sieving unit ( 1) and a vacuum suction device (17) is provided above the sieving unit (1).
And a particle dispersion unit (15) comprising a suction pipe (18) connected to a suction section of the reduced-pressure suction device (17) and a discharge pipe (19) extending from a discharge section.
8) and the discharge pipe (19) are connected to the lower sieving unit (1).
A sieve that is opened near the upper part of the sieve net (3).

(7) In a sieving apparatus in which a nozzle for blowing air toward a substantially circular screen of a sieve mesh is rotatably provided immediately below the screen of the sieve, a nozzle (3) includes: A rotary nozzle (4), a drive unit (5) for supporting and driving the rotary nozzle, and an air introduction pipe (6) to the drive unit are assembled in a cylindrical frame (2), and a sieving unit ( 1), a cylindrical frame (9), a partition (11) having a nozzle (10) for generating a swirling flow suspended in the frame, and a partition (11) formed at the bottom of the screen. Upright in the center, and
A cyclone unit (8) comprising an exhaust pipe (12) communicating with a blower opened near the lower part of the partition wall is provided in series, and a vacuum suction device (17) is provided above the sieve sieving unit (1). A suction pipe (18) connected to the suction section of the reduced-pressure suction device (17), and a discharge pipe (19) extending from the discharge section.
Is installed, and the suction pipe (18) and the discharge pipe (19) are opened near the upper part of the sieve net (3) of the lower sieving unit (1). A sieving apparatus.

[0020]

A plurality of sieving units are stacked, and each air introduction pipe of each sieving unit is independently opened to the atmosphere. The air introduction pipes are sequentially opened to the atmosphere and sieved one by one. Drive the unit. In addition, a cyclone unit is attached to the lower part of the lowermost sieving unit to separate and collect fine particles mixed in the exhaust gas. Further, a particle dispersing unit is assembled on the uppermost of the uppermost sieving unit, and the supplied cohesive fine particles are dispersed during driving so as to be suitable for sieving.

[0021]

FIG. 1 is a vertical sectional front view for explaining the basic structure of the apparatus of the present invention, and FIG. 2 is a cross-sectional plan view taken along the line AA of FIG. (1) is a sieving unit, and a cylindrical frame (2);
To a sieve mesh (3) incorporated in a cylindrical frame (2), a rotary nozzle (4), a drive unit (5) for supporting and driving the rotary nozzle (4), and a drive unit (5) And an air introduction pipe (6). The cylindrical frame (2) includes a frame having a sieve mesh (3) stretched on the lower surface, and a rotary nozzle (4) and a driving unit (5) provided continuously below the frame. ,and,
And a frame in which the air introduction pipe (6) is incorporated. FIG. 1 shows a stack of two or more sets of the above sieving units (1) in the vertical direction. In the drawing, two sets of sieving units (1) and (1) are stacked. The outer ends of the air introduction pipe (6) of the upper sieving unit (1) and the air introduction pipe (6) of the lower sieving unit (1) are fixed to the frame (2), The end protruding outside the frame (2) has an inlet opening to the atmosphere, and the inlet is opened and closed by an air cylinder (25) driven by compressed air. The control of the air cylinder (25) is performed by the compressed air supply pipe (26).
The operation is performed by a valve (7) provided in the above. In addition, (P) is a compressed air source, and an air cylinder (25) that opens and closes each of the air introduction pipes (6) of the plurality of sieving units (1) is connected to the compressed air source (P). Compressed air supply pipe (2
The valve (7) of (6) is selectively operated to open the corresponding air introduction pipe (6) to the atmosphere.

(8) is a cyclone unit provided continuously below the lowermost sieve unit (1), and has a cylindrical frame (9) and a nozzle (9) for generating a plurality of swirling airflows at the peripheral edge. Exhaust air that communicates with a partition (11) having a vertically extending 10) and a blower (not shown) opened upright from the bottom to the center of the frame (9) and opened near the lower part of the partition (11). And a tube (12). The frame (9) includes a frame having a partition (11), a frame forming a cyclone chamber (13), and a frame having a leg (14).

A particle dispersion unit (15) for dispersing the coagulable fine particles, which is provided above the uppermost sieving unit (1), has a reduced pressure suction device (17) and a suction pipe connected to the suction portion of the reduced pressure suction device. (18) and a discharge pipe (19) extending from the discharge part of the reduced-pressure suction device (17). The suction pipe (18) and the discharge pipe (19) are connected to the uppermost sieving unit (1). It is opened near the upper part of the sieve screen (3). In addition,
The decompression suction device (17) is, for example, a sirocco fan, and (16) is a drive motor.

As shown in FIG. 3, the drive unit (5) of the sieving unit (1) supports a rotating shaft (20) via a bearing at the center of the lower surface of the cylindrical air chamber (5a). The rotating nozzle (4) is attached to the upper end of the rotating shaft (20). Further, a driving part (5) of the rotary nozzle (4) is formed by connecting the air introduction pipe (6) so as to direct the connection direction to the peripheral wall of the air chamber (5a).

The skirt (21) of the rotary nozzle (4)
Forms a labyrinth mechanism (22) in cooperation with the upper part of the air chamber (5a), reduces friction when the rotary nozzle (4) rotates, and prevents air flow from leaking from the part. . The inside of the rotary nozzle (4) has an air flow path (2) partitioned by radial ribs (23) between a rotary shaft (20) of the rotary nozzle (4) and a skirt (21) of the rotary nozzle (4).
4) and communicates with the cylindrical air chamber (5a).
The outer end of the air inlet pipe (6) is fixed to the inner cylindrical frame (2), and has an air inlet at the outer end which is opened and closed by an air cylinder (25).

In the apparatus shown in FIG. 1, a predetermined amount of particles to be sieved is supplied to the upper part of the screen (3) of the upper sieving unit (1), and the air cylinder (25) of the upper air inlet pipe (6) is supplied. Is opened to open the upper air introduction pipe (6) to the atmosphere, and at the same time, intake air acts on the exhaust pipe (12) of the lower cyclone unit (8) with a blower. Then, the entire inside of the apparatus is set to a negative pressure, and the air corresponding to the negative pressure is sucked from the outer end of the air introducing pipe (6). The air introduced from the air introduction pipe (6) forms a swirling flow in the air chamber (5a), flows into the skirt portion (21) of the rotating nozzle (4) while swirling, and enters the rotating nozzle (4). A turning drive force is generated, thereby rotating the rotary nozzle (4). The air that has flowed into the rotary nozzle (4) is sucked out of a slit (4a) provided on the upper surface of the rotary nozzle (4). The sucked air is a rotating nozzle (4)
A dynamic pressure is applied to the lower surface of the sieve mesh (3) placed right above the sieve to disperse and suspend particles on the sieve mesh (3). The rotating nozzle (4) is urged by an air flow flowing into the air flow path (24) while forming a swirling flow, and rotates at a constant speed. Floats and swings. The upper part of the frame that stretches and supports the sieve net (3) is sealed, and the inside of the device is opened into the lowermost cyclone unit (8), and the exhaust pipe (1) connected to the blower is opened.
Since the negative pressure is applied by 2), the fine particles on the sieve mesh (3) pass through a portion of the sieve mesh not on the slit (4a) of the rotary nozzle (4) and into the lower sieving unit together with air. It is sucked and falls below the screen (3). When the upper sieving unit is driven for a set time, for example, 5 seconds, the upper sieving unit is stopped, the lower sieving unit is subsequently driven, and the same operation as described above is caused. The fine particles are sieved. The above operation is repeated several times. The fine particles passing through the sieve mesh of the lower sieve sieving unit are supplied to the nozzle (1) provided on the partition (11) of the cyclone unit (8).
0), is sent into the cyclone chamber (13) together with the air as a swirling flow, the fine particles are deposited at the lower portion along the peripheral wall, and only the air is discharged to the outside from the exhaust pipe (12).

[0027] In the above manner, particles having a particle size equal to or larger than the mesh of the sieve mesh are sieved on the sieve mesh of the upper sieve unit, and particles having an intermediate diameter are sieved on the lower sieve mesh; Ultra-fine particles are collected in the cyclone chamber.

The particle dispersion unit (15) on the sieving unit (1) is provided when sieving the coagulable fine particles.
The coagulable fine particles on the sieve screen (3) are circulated together with air to prevent the particles from coagulating.

The rotation speed of the rotary nozzle (4) increases in proportion to the strength of the swirling flow generated in the air chamber. (6a) shown in FIGS. 2 and 3 is an air inlet tube for adjusting the rotation speed, and is connected to the cylindrical air chamber (5a) in a direction opposite to the air inlet tube (6). Connected to be. When the amount of air flowing through the air introduction pipe (6a) for adjusting the rotation speed increases, the swirling flow generated in the cylindrical air chamber is offset by the air flow flowing from the air introduction pipe, and as a result, the rotation speed of the rotary nozzle becomes lower. descend. The rotation speed of the rotary nozzle is adjusted to the optimum sieving condition according to the powder properties by operating the air flow flowing in the second air introduction pipe.

FIG. 4 shows an apparatus in which a particle dispersing unit (15) for dispersing coagulable particles and a cyclone unit (8) are assembled above and below a set of sieving units (1). Air introduction pipe (6) because one set of minute unit
Is unnecessary. The detailed structure and operation of FIG. 4 are the same as those of the device of FIG. 1, and a description thereof will be omitted.

[0031]

According to the present invention, since the air introduction pipes of the respective sieve units are independently and selectively opened to the atmosphere, the amount of air per sieve unit is reduced by the negative pressure acting in the apparatus. Is proportional to In other words, only the upper sieving unit is aired, and then only the lower sieving unit is aired,
This is a so-called “intermittent air guide” method that repeats this. Therefore,
Compared with the “simultaneous air guide” system, the size of the negative pressure generator can be reduced. Further, the air introduction time can be set optimally in consideration of the sieving characteristics of each particle. Furthermore, since the particle dispersion unit is provided on the uppermost sieving unit, a good sieving effect can be obtained even for primary particles that are easily aggregated due to the strength of surface activity peculiar to fine particles.
Further, the fine particles that have passed through the sieve net of the lowermost sieve unit are conventionally collected by a bag filter of a separately installed vacuum suction device or a method of collecting by a cyclone provided separately. According to the present invention, since the cyclone unit is directly and simply incorporated into the lower part of the lowermost sieving unit, the fine particles mixed in the exhaust gas can be reliably and easily collected in the cyclone chamber. Further, the cyclone unit of the present invention cannot be incorporated in a motor-driven rotary nozzle type sieving apparatus which is conventionally commercially available, but can be easily incorporated in the sieving apparatus of the present invention.

[Brief description of the drawings]

FIG. 1 is a vertical sectional front view of a sieving apparatus according to the present invention.

FIG. 2 is a cross-sectional plan view taken along the line AA of FIG. 1;

FIG. 3 is an enlarged sectional view of a sieving unit.

FIG. 4 is a drawing showing a modification of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 sieving unit 2 frame 3 sieve mesh 4 rotating nozzle 5 driving unit 6 air introduction pipe 7 valve 8 cyclone unit 9 frame 10 turning nozzle 11 partition 12 exhaust pipe 15 particle dispersion unit 16 motor 17 sirocco fan 18 suction pipe 19 discharge Pipe P compressed air source

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-200944 (JP, A) JP-A-57-153775 (JP, A) JP-A-53-40469 (JP, A) 132280 (JP, U) Shokai Sho 51-94070 (JP, U) Shoko Sho 59-39493 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) B07B 4/08 B07B 9 / 00

Claims (7)

(57) [Claims] Claims: 1. A sieving apparatus in which a nozzle for blowing air toward a substantially circular screen of a sieve mesh is rotatably provided immediately below the screen of the sieve.
A drive unit for supporting and driving the rotary nozzle, and an air introduction pipe to the drive unit are assembled in a cylindrical frame to constitute a sieving unit, and a plurality of the sieving units are stacked, and the plurality of sieving units are stacked. A sieving apparatus characterized in that each air introduction pipe of the unit is independently opened to the atmosphere. 2. A sieving apparatus in which a nozzle for blowing air toward a net surface of a substantially circular sieve mesh is rotatably provided immediately below the sieve mesh surface, wherein the sieve net, a rotating nozzle,
A drive unit for supporting and driving the rotary nozzle, and an air introduction pipe to the drive unit are assembled in a cylindrical frame to constitute a sieving unit, and a plurality of the sieving units are stacked, and the plurality of sieving units are stacked. Each air introduction pipe of the unit is independently opened to the atmosphere, and a cylindrical frame and a nozzle for generating a swirling air flow in the frame are vertically installed below the lowermost sieving unit. And the upright from the bottom to the center of the frame,
And a cyclone unit comprising a blower opened in the vicinity of the lower part of the partition and an exhaust pipe communicating with the blower. 3. A sieving apparatus in which a nozzle for blowing air toward a net surface of a substantially circular sieve mesh is rotatably provided immediately below the sieve mesh surface, wherein the sieve net, a rotating nozzle,
A drive unit for supporting and driving the rotary nozzle, and an air introduction pipe to the drive unit are assembled in a cylindrical frame to constitute a sieving unit, and a plurality of the sieving units are stacked, and the plurality of sieving units are stacked. Each of the air introduction pipes of the unit is independently opened to the atmosphere. Above the uppermost sieving unit, a reduced pressure suction device, a suction pipe connected to a suction portion of the reduced pressure suction device, and a discharge portion A particle dispersing unit comprising a discharge pipe extending from the sieving apparatus, wherein the suction pipe and the discharge pipe are opened near the upper part of the screen of the uppermost sieving unit. 4. A sieving apparatus in which a nozzle for blowing air toward a net surface of a substantially circular sieve net is rotatably provided immediately below the sieve net surface, wherein the sieve net, a rotating nozzle,
A drive unit for supporting and driving the rotary nozzle, and an air introduction pipe to the drive unit are assembled in a cylindrical frame to constitute a sieving unit, and a plurality of the sieving units are stacked, and the plurality of sieving units are stacked. Each air introduction pipe of the unit is independently opened to the atmosphere, and a cylindrical frame and a nozzle for generating a swirling air flow in the frame are vertically installed below the lowermost sieving unit. And the upright from the bottom to the center of the frame,
And, a cyclone unit consisting of an exhaust pipe communicating with a blower opened near the lower part of the partition wall is connected, and a vacuum suction device and a suction unit of the vacuum suction device are provided above the uppermost sieve unit. A particle dispersing unit comprising a continuous suction pipe and a discharge pipe extending from the discharge unit is installed, and the suction pipe and the discharge pipe are opened near the upper part of the screen of the uppermost screening unit. Sieving device. 5. A sieving apparatus in which a nozzle for blowing air toward a net surface of a substantially circular sieve mesh is rotatably provided immediately below the sieve mesh surface, wherein the sieve mesh, a rotating nozzle,
A drive unit that supports and drives the rotary nozzle, and an air introduction pipe to the drive unit is incorporated into a cylindrical frame to form a sieving unit.At the lower part of the sieving unit, a cylindrical frame, A cyclone unit consisting of a partition wall provided with a nozzle for generating a swirling flow in the frame body and an exhaust pipe which stands upright from the bottom to the center of the frame body and communicates with a blower opened near the lower part of the partition wall. A sieving apparatus characterized by being provided. 6. A sieving apparatus in which a nozzle for blowing air toward a net surface of a substantially circular sieve mesh is rotatably provided immediately below the sieve mesh surface.
A drive unit for supporting and driving the rotary nozzle, and an air introduction pipe to the drive unit are assembled into a cylindrical frame to form a sieving unit. At the top of the sieving unit, a reduced-pressure suction device, A suction pipe connected to the suction unit of the suction device and a particle dispersion unit including a discharge pipe extending from the discharge unit are installed, and the suction pipe and the discharge pipe are opened near the upper part of the screen of the lower sieving unit. A sieving apparatus. 7. A sieving apparatus in which a nozzle for blowing air toward a net surface of a substantially circular sieve mesh is rotatably provided immediately below the sieve mesh surface, wherein the sieve net, a rotating nozzle,
A drive unit that supports and drives the rotary nozzle, and an air introduction pipe to the drive unit is incorporated into a cylindrical frame to form a sieving unit.At the lower part of the sieving unit, a cylindrical frame, A cyclone unit consisting of a partition wall provided with a nozzle for generating a swirling flow in the frame body and an exhaust pipe which stands upright from the bottom to the center of the frame body and communicates with a blower opened near the lower part of the partition wall. And a particle dispersion unit comprising a reduced-pressure suction device, a suction pipe connected to a suction portion of the reduced-pressure suction device, and a discharge pipe extending from a discharge portion, and installed above the sieving unit. A sieving device, characterized in that the pipe is opened near the upper part of the screen of the lower sieving unit.