JP2000237636A - Cyclone device for collecting powder, and producing device of toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cyclone device for collecting powder by which particulate matter can be collected stably and efficiently for the sucked air quantity of a wide range in the feed part of the particulate matter. SOLUTION: The cyclone device is equipped with a body 26 having an inner cylinder 22 and an outer cylinder 24 which are arranged in a concentric circular shape and with the feed part 30 of particulate matter which is extended in the direction of a tangential line of the body 26. Particulate matter is collected by giving swing movement to gas containing particulate matter. A secondary air-introducing route 32 is provided in order to supply secondary air to the inside of the body side in the feed part of the particulate matter. A secondary air control valve 34 is provided in the secondary air-introducing route 32. A secondary air-straightening plate 36 is provided in the vicinity of a crossing part of the feed part 30 of particulate matter and the secondary air-introducing route 32.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for collecting powder and granules utilizing centrifugal force, in particular, a cyclone apparatus, and an apparatus for producing a toner for electrostatic charge development incorporating the cyclone apparatus in a toner collecting step. About.

[0002]

2. Description of the Related Art At present, kneading and pulverizing methods are mainly used in the production of electrophotographic toners, and one of them is a dry production process. In the dry manufacturing process, a powder collecting device is required to process, process, transport, and handle the powder in an air atmosphere. In the conventional electrophotographic toner manufacturing process, the toner is transported by air between each step,
In many cases, the toner is collected by a centrifugal force collecting device, mainly a cyclone device, and many collecting devices are used from a raw material process to a final process of the toner.

[0003] These collecting devices cannot completely separate the toner from the air, and the toner not collected by the collecting device is collected by a dust filter provided in an exhaust pipe of the collecting device. You. However, since the collected amount of the collected material for each filter is small, the regeneration is costly and troublesome, and the manufacturing process is often complicated.
Therefore, it has been desired to improve the performance and efficiency of the trapping device itself.

[0004] A device for collecting particulates utilizing centrifugal force, particularly a cyclone, connects a horizontal straight pipe to a gas inlet of an outer cylinder,
The air flow (dust-containing air flow) containing the powder and granules is guided into the outer cylinder through a straight pipe. The dust-containing airflow introduced into the outer cylinder is
It descends while forming a swirling flow flowing along the wall surface, is further accelerated in the conical portion, and then reverses in the vicinity of the dust collection chamber, becomes an ascending flow, and is discharged from the inner cylinder to the outside of the system. The granular material moves toward the outer cylinder under the influence of the centrifugal force due to the swirling flow. The granular material that has reached the outer cylinder descends along the outer cylinder and is collected in the dust collection chamber. The trap performance is set at the cyclone inlet wind speed of 15 to 25m /
It is ensured by selecting in the range of about s and optimizing the dimensions of each part in consideration of the pressure loss. In addition, if the inlet wind speed is less than 15 m / s, the effect of centrifugal force generated by the swirling motion is not sufficiently obtained, so the collection performance is reduced, and if it exceeds 25 m / s, the flow is disturbed Therefore, the trapping performance is reduced.

[0005] In a pulverizer and a classifier used in the toner production process, it is necessary to control the amount of air to be sucked depending on the material to be treated and the desired particle size. 6 and 7 are schematic diagrams of a conventional cyclone-based trapping system 1. FIG. The collection system 1 includes a cyclone device 2, a bag filter 3 connected to the cyclone device 2, a blower 5 connected to the bag filter 3, and a flow control valve 4 provided in a pipe connecting the bag filter 3 and the blower 5. Is provided. Further, the cyclone device 2 includes a main body 6, a powder supply unit 7 extending in a tangential direction of the main body 6, and a dust collection box 8 disposed below the main body 6. Further, the main body 6 is constituted by an inner cylinder 9 arranged vertically, and an outer cylinder 10 arranged concentrically with the inner cylinder 9, and the outer cylinder 10 is constituted by an upper cylindrical portion 10A and a lower conical portion 10B. I have. In a conventional toner manufacturing process, a collecting system as shown in FIGS. 6 and 7 is incorporated in a pulverizer, a classifier, or the like. In this conventional collection system 1,
Since the flow control valve 4 is located immediately before the blower 5,
When the suction air volume of a crusher, a classifier, or the like decreases, the air volume flowing into the cyclone also decreases. As a result, the air flow cannot be controlled within the optimum flow rate range with these cyclones, and the collection performance changes depending on the material to be treated and the particle size thereof, and the yield is lower than when operating at the optimal air flow. It drops significantly. In particular, in a toner plant that manufactures toners of various kinds with small particle diameters and materials with a single line, there is a problem that the cyclone collecting performance is degraded due to the difference in suction air volume.

In Japanese Patent Application Laid-Open No. 7-256152, in order to ensure a stable cyclone collection performance even under low air flow conditions, a part of the dust-containing gas discharged from the inner cylinder of the cyclone is again supplied to the cyclone supply port. A circulation path for circulation and a blower are provided. However, in the toner manufacturing process, there is a problem of fusing inside the blower and a problem that it is difficult to change the type and to perform cleaning, so that it is impossible to incorporate this mechanism.

[0007]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to overcome the above-mentioned drawbacks, and has provided a cyclone device capable of stably and efficiently collecting powder particles under a wide range of suction airflow in a powder supply section. And a toner manufacturing apparatus using the same.

[0008]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies so as to secure an optimal suction air volume flowing into a cyclone and to supply powders from an optimal position of a cyclone supply port. A secondary air introduction path for supplying secondary air is provided inside the main body side of the granular material supply unit, and secondary air is introduced from the secondary air introduction path to bias the dust-containing airflow toward the wall surface of the outer cylinder. The above-mentioned problem can be solved by causing the flow to flow. That is, the configuration of the present invention is as follows. (1) A cyclone device that includes a main body having an inner cylinder and an outer cylinder, and a base cyclone supply unit extending in a tangential direction of the main body, and applies a swirling motion to a gas containing the granular material to collect the granular material. In the above, a secondary air introduction path for supplying secondary air is provided inside the main body side of the cyclone supply section, and an air amount adjusting means is provided in the secondary air introduction path, and the powder and granular material supply section and the secondary air are provided. A cyclone device comprising a secondary air straightening plate provided near an intersection of an introduction path. (2) The cyclone device according to (1), wherein a portion of the secondary air introduction path on the side of the powdery material supply section is arranged along the outer cylinder. (3) The cyclone device according to (1) or (2), wherein a movable guide plate is provided inside the secondary air introduction path on the side of the granular material supply section. (4) An apparatus for producing a toner, wherein at least one of the cyclone apparatuses (1), (2) and (3) is incorporated in a toner collecting step.

In the above invention, since the air amount adjusting means is provided in the secondary air introduction path, the amount of the secondary air is adjusted according to the suction air amount of the granular material supply section, and the gas supplied to the main body is adjusted. The flow rate can be controlled optimally. In addition, since the dust-containing airflow is deflected toward the wall of the outer cylinder and flows in, the dust-containing airflow can be efficiently put on the swirling flow near the outer cylinder, and the yield of the centrifugal force can be effectively utilized by effectively utilizing the effect of the centrifugal force. Can be improved. Further, since the secondary air straightening plate is provided, the dust-containing airflow is not disturbed when the secondary air flows.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a collecting device according to the present invention. FIG. 1 is a plan view for explaining the concept of the collecting device 20 according to the first embodiment of the present invention, and FIG. 2 is a front view of the collecting device 20 of the present invention. FIG.
Is a collection system 50 incorporating the collection device 20 of the present invention.
FIG. 1 and 2 includes a main body 2 having an inner cylinder 22 and an outer cylinder 24 arranged concentrically.
6. An air flow that extends in the tangential direction of the main body 26 and contains the powder 28
(Particle supply unit 30 for introducing (dust-containing airflow) between the inner cylinder 22 and the outer cylinder 24) Secondary air for supplying secondary air to the inside of the main body side of the particle supply unit 30 An introduction path 32, a secondary air control valve 34 as an air amount adjusting means provided in the secondary air introduction path 32, provided near the intersection of the powder supply unit 30 and the secondary air introduction path 32, Secondary air flow regulating plate 36 for adjusting turbulence of the inflowed secondary air flow, and outer cylinder 24
And a dust collecting box 38 that collects the separated granular material 28 disposed below. The outer cylinder 24 has a cylindrical portion 24A and a conical portion 2 whose diameter decreases with increasing distance from the cylindrical portion 24A.
4B. Further, the inner cylinder 24 is shorter than the outer cylinder 24 and discharges the gas separated from the granular material 28. The main body 26 side of the secondary air introduction path 32 is a cyclone supply port 40, and the secondary air rectifying plate 36 is arranged substantially parallel to the outer wall surface 30 </ b> A of the granular material supply unit 30.

The collection system 50 of the present invention comprises a bag filter 4 connected to the collection device 20 and the inner cylinder 22.
2 and a blower 44 connected to the bag filter 42.

In the present invention, as shown in FIGS. 1 and 2, the dust-containing airflow flowing from the granular material supply unit 30 is supplied into the cyclone supply port 40. By opening the secondary air control valve 34, the secondary air that has flowed in from the secondary air introduction path 32 is supplied into the cyclone supply port 40 along the inner wall surface 30 </ b> B of the granular material supply unit 30. . Due to this secondary air flow, the powder particles 28 flow into the main body 26 from the cyclone supply port 40 while being biased toward the wall surface of the outer cylinder 24. The dust-containing airflow that has flowed into the main body 26 makes a revolving motion along the wall surface of the outer cylinder 26, and the particles 28 that have reached the outer cylinder 26
And is collected by the dust collection box 38. At this time, as described above, the particles 28 in the cyclone supply port 40 are biased toward the outer cylinder, so that these particles 28 are efficiently put on the swirling flow near the outer cylinder, and the effect of the centrifugal force is exerted. Can be used effectively. Further, the separated airflow rises on the central axis of the main body 26 and the cyclone inner cylinder 2
It is discharged from 2.

Since the secondary air is rectified by the secondary air rectifying plate 36 so as to have a velocity component in the same direction as the dust-containing airflow, the airflow in the main body 26 is controlled within a wide range of the secondary air supply amount. It is possible to operate the collection device 20 without disturbing. In addition, when collecting dust at a flow rate that can ensure sufficient dust collection performance without secondary air, closing the secondary air control valve provides dust collection performance equivalent to that of a conventional cyclone.

As described above, the secondary air supply amount is set in accordance with the flow rate of the dust-containing airflow in the powder supply unit 30, and the secondary air is further supplied along the inner wall surface 30B of the powder supply unit 30. By supplying the powder into the cyclone supply port 40, it is possible to always ensure the optimal dust collection performance under a wide range of suction air volume in the powdery material supply section.

FIG. 4 is a sectional view of a trapping device 60 according to a second embodiment of the present invention. In addition, about the structure same as the collection apparatus 20, the same code | symbol is attached | subjected and description is abbreviate | omitted. In the trapping device 60, a portion of the secondary air introduction path 62 on the main body side is disposed along the outer cylinder 26, and is curved in the same direction as the cyclone turning direction. Thereby, the generation of the swirling flow in the main body is assisted, and the trapping performance can be further improved.

FIG. 5 is a sectional view of a trapping device 70 according to a third embodiment of the present invention. In addition, about the structure same as the collection apparatus 20, the same code | symbol is attached | subjected and description is abbreviate | omitted. In this trapping device 70, a movable guide plate 72 that is rotatable about the intersection of the powder supply unit 30 and the secondary air introduction path 32 is provided. By setting the angle of the guide plate 72 and changing the flow path width, the velocity distribution at the cyclone supply port 40 is kept uniform,
The secondary air is supplied into the main body 26 without mixing the dust-containing airflow into the secondary air flow, and the particles can be efficiently biased toward the outer cylinder side, thereby further improving the dust collection performance. Can be.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments.

Styrene-acrylic polymer 47 parts by weight Magnetic powder (BL-220, manufactured by Titanium Industry Co., Ltd.) 49 parts by weight Charge control agent (Bontron P-51, manufactured by Orient Chemical Industry Co., Ltd.) 1 part by weight Polypropylene (Viscose 660P) 3 parts by weight The above materials are melted and kneaded, and the volume average particle size is measured with a mechanical grinder.
ground to d ₅₀ = 7 [mu] m, to obtain a pulverized toner particles.

A recovery experiment was conducted on the above-mentioned pulverized toner particles by using a collecting device shown in FIG. The cyclone used as the collection device is a semicircular spiral type (where the spiral channel for gas introduction extends over a half circle), the inner diameter of the outer cylinder is 280 mm, and the height of the outer cylinder is 280 mm.
The width of the supply port attached to the outside of the outer cylinder was 330 mm, the height of the conical portion was 800 mm, the width of the supply port was 70 mm, and the height was 135 mm. The diameter of the cyclone inner cylinder was 155 mm, and the insertion length in the outer cylinder was 220 mm. The cyclone supply port 40 had a width of 25 mm and a height of 135 mm. The secondary air straightening plate 36 has a width of 2 mm and the inner wall surface 30 of the granular material supply unit 30.
The distance w from B was 25 mm. 15 kg of the above-mentioned pulverized toner particles were supplied from the upstream of the powder supply unit 30 at a supply speed of 30 kg / h using a quantitative supply machine, and the recovery rate in the dust collection box 38 was obtained. In addition, the same experiment was repeated three times and compared with the average value of the recovery rates. (Embodiment 1) Using the mechanism shown in FIG. 1, the air flow rate of the airflow discharged from the inner cylinder 22 was set to 8.0 m ³ / min (20 ° C., 1 atm or less), Was adjusted to 10 m / s, and the recovery test was performed by adjusting the secondary air control valve 34. (Embodiment 2) Using the mechanism shown in FIG. 1, the air flow rate of the airflow discharged from the inner cylinder 22 is set to 8.0 m ³ / min, and the wind speed in the powder material supply unit 30 is set to 20 m / s. The secondary air control valve 34 was adjusted to perform a recovery test. (Embodiment 3) Using the mechanism shown in FIG. 4, the air flow rate of the airflow discharged from the inner cylinder 22 is set to 8.0 m ³ / min, and the wind speed in the powder material supply unit 30 is set to 10 m / s. The secondary air control valve 34 was adjusted to perform a recovery test. (Embodiment 4) Using the mechanism shown in FIG. 5, the air flow rate of the airflow discharged from the inner cylinder 22 is set to 8.0 m ³ / min, and the wind speed in the powder material supply unit 30 is set to 10 m / s. The secondary air control valve 34 was adjusted, and the distance between the movable guide plate 36 and the wall surface 30B inside the granular material supply unit 30 was adjusted to 25 mm, and a collection test was performed. (Comparative Example 1) Using the conventional cyclone mechanism shown in FIG. 7, a recovery test was performed by adjusting the air flow rate of the air flow discharged from the inner cylinder 10 so that the wind speed in the powder supply unit 7 became 10 m / s. Was carried out. (Comparative Example 2) Using the conventional cyclone mechanism shown in FIG. 7, a recovery test was performed by adjusting the air flow rate of the airflow discharged from the inner cylinder 10 so that the wind speed in the powder supply unit 7 became 20 m / s. Was carried out. (Comparative Example 3) A recovery test was performed under the same conditions as in Example 1 except that the secondary air straightening plate 36 was removed.

Table 1 shows the recovery test results of the examples of the present invention and the comparative examples.

[0021]

[Table 1]

As is apparent from a comparison between Examples 1 and 2 and Comparative Examples 1 to 3, an appropriate amount of secondary air is sucked and rectified from the inside of the main body side of the powder and granular material supply section, thereby obtaining the powder and granular material. It can be seen that a high yield is obtained irrespective of the suction air volume in the supply section. Further, it can be seen that the dust collection performance of the cyclone is further improved by giving the secondary air a swirling speed component as in Example 3. Further, it can be understood that the dust collection performance of the cyclone is also improved by adjusting the width of the secondary air supply flow path and reducing the speed difference between the secondary air and the dust-containing airflow as in Example 4.

[0023]

According to the present invention, by adopting the above structure, an optimal flow velocity is secured without disturbing the swirling flow in the cyclone, and a centrifugal force is efficiently applied to the powder and granules. As a result, under a wide range of suction air volume in the granular material supply unit, it is possible to stably collect the granular material efficiently, improve the productivity of the granular material product, and save resources and energy. Can greatly contribute to

[Brief description of the drawings]

FIG. 1 is a plan view for explaining the concept of a trapping device according to a first embodiment of the present invention.

FIG. 2 is a front view of the collection device of FIG.

FIG. 3 is a schematic diagram of a collection system incorporating the collection device of the present invention.

FIG. 4 is a plan view of a trapping device according to a second embodiment of the present invention.

FIG. 5 is a plan view of a trapping device according to a third embodiment of the present invention.

FIG. 6 is a schematic view of a conventional cyclone collecting system.

FIG. 7 is a plan view of the cyclone of FIG. 6;

[Explanation of symbols]

 REFERENCE SIGNS LIST 20 collection device 22 inner cylinder 24 outer cylinder 26 main body 30 granular material supply section 32 secondary air introduction path 34 secondary air control valve 36 secondary air straightening plate 50 collection system 60 collection apparatus 62 secondary air introduction path 70 Collection device 72 Movable guide plate

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takeshi Tanabe 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd. (72) Inventor Hiroyuki Moriya 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture Fuji Xerox Co., Ltd. Reference) 2H005 AB04 4D053 AA03 AB01 BA01 BB02 BC01 BD04 CA17

Claims (4)

[Claims] An apparatus includes a main body having an inner cylinder and an outer cylinder, and a granular material supply portion extending in a tangential direction of the main body, and applies a swirling motion to a gas containing the granular material to collect the granular material. A secondary air introduction path for supplying secondary air to the inside of the main body side of the granular material supply unit, an air amount adjusting means is provided in the secondary air introduction path, And a secondary air straightening plate provided near an intersection of the secondary air introduction path and the secondary air introduction path. 2. The cyclone apparatus according to claim 1, wherein a portion of the secondary air introduction path on the side of the powdery material supply section is arranged along the outer cylinder. 3. The cyclone device according to claim 1, wherein a movable guide plate is provided inside the secondary air introduction path on the side of the powdery material supply section. 4. At least one of claims 1 to 3
An apparatus for producing a toner, comprising two cyclone devices incorporated in a toner collecting step.